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  • richardmitnick 11:44 am on November 17, 2022 Permalink | Reply
    Tags: "FETs": Field-effect transistors, "Tunneling Electrons Confirm New Device Structure for Energy-Efficient Chips", , , Penn engineers have nearly halved the amount of voltage needed for switching., , The device called a TFET (pronounced tee-fet) relies on a physical property known as tunneling., , The TFET design can likely be miniaturized to degrees that a standard FET cannot and accomplish even faster switching., , Tunneling FET technology, Tunneling requires much lower voltages than the thermal injection used in state-of-the-art FETs.   

    From The School of Engineering and Applied Science At The University of Pennsylvania: “Tunneling Electrons Confirm New Device Structure for Energy-Efficient Chips” 

    From The School of Engineering and Applied Science

    At

    U Penn bloc

    The University of Pennsylvania

    11.8.22
    Devorah Fischler

    1
    Scientists have been experimenting with tunneling FET technology for decades but have been hindered by insurmountable trade-offs in power and performance. The Jariwala Lab TFET design (above) overcomes this trade-off, both operating at low voltages and achieving enough current density to drive applications at the systems and circuit level.

    Field-effect transistors (FETs) offer some of the most energy-efficient switching in commercial computing chips.

    Yet even when operating with minimum possible voltages, FETs still consume too much power to support the accelerating computational demands of advanced technologies and respond to the energy crisis’ appeals for lower-power hardware.

    Researchers from the University of Pennsylvania’s School of Engineering and Applied Science have redesigned FETs with these energy imperatives in mind.

    Creating devices that harness physics in ways unlike those used in commercial transistors, Penn engineers have nearly halved the amount of voltage needed for switching.

    The new logic device design is the subject of a recently published study in Nature Electronics [below] that was co-led by Deep Jariwala, Assistant Professor in the Department of Electrical and Systems Engineering (ESE), and Jinshui Miao, former postdoctoral researcher in ESE and current professor at the Shanghai Institute of Technical Physics, along with Chloe Leblanc and Xiwen Liu, Ph.D. students in ESE. The team worked in collaboration with researchers from the National Institute of Standards and Technology, the Chinese Academy of Sciences, Theiss Research and the Air Force Research Laboratory.

    “Computing devices today contain so many transistors—tens of billions—that even a small reduction in energy usage would make a big difference,” says Jariwala. “Our results with this design represent a big reduction, which means the impact on overall energy efficiency will be huge. It undercuts current theoretical minimums by an astonishing amount.”

    The device, called a TFET (pronounced tee-fet), relies on a physical property known as tunneling. Particles tunnel when they move through energy barriers rather than over them.

    “Imagine an electron moving through a FET like a ball that needs to roll up a hill in order to get to the other side,” says Leblanc. “In a TFET, the ball doesn’t need to roll up the hill—it gets a little push and manages to tunnel through it instead. What’s exciting about this study is that we can confirm through multiple device demonstrations and simulations that this physics, the electron tunneling, is definitely the reason our transistor is so effective at low power.”

    2
    Particles tunnel when they move through energy barriers rather than over them. Image credit: Danko Georgiev.

    Tunneling requires much lower voltages than the thermal injection used in state-of-the-art FETs.

    Scientists have been experimenting with tunneling FET technology for decades but have been hindered by insurmountable trade-offs in power and performance. Until now, TFETs were able to either operate below the theoretical voltage minimum (60mV/decade, a metric known as the Boltzmann limit) or with sufficient current density at the drain terminal to drive applications at the circuit and system levels. The Penn Engineering research team’s design does both.

    3
    A flake of InSe, an experimental new semiconductor, in the physical TFET device.

    “By finally overcoming that trade-off, we have cleared a path for the future integration of TFETs into high-performance, low-power microelectronics,” says Jariwala. “Central to our solution is an experimental new semiconductor called indium selenide (InSe), which is clean enough in terms of crystal quality and achieves high-drive current density. Now that we have a structure that allows for both high current density and low voltage, we can start to build a strong case for substituting a standard FET with a TFET.”

    The experiments point to a promising future for TFETs beyond their energy efficiency.

    “With future development, these devices have the potential to surpass further FET limitations in size and switching speed,” says Miao. “Our TFET design can likely be miniaturized to degrees that a standard FET cannot and accomplish even faster switching. It’s a very promising solution not only for energy usage, but also other versatile device applications requiring complex computational tasks.”

    Science paper:
    Nature Electronics

    See the full article here .

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    Please help promote STEM in your local schools.

    Stem Education Coalition

    The School of Engineering and Applied Science is an undergraduate and graduate school of The University of Pennsylvania. The School offers programs that emphasize hands-on study of engineering fundamentals (with an offering of approximately 300 courses) while encouraging students to leverage the educational offerings of the broader University. Engineering students can also take advantage of research opportunities through interactions with Penn’s School of Medicine, School of Arts and Sciences and the Wharton School.
    Penn Engineering offers bachelors, masters and Ph.D. degree programs in contemporary fields of engineering study. The nationally ranked bioengineering department offers the School’s most popular undergraduate degree program. The Jerome Fisher Program in Management and Technology, offered in partnership with the Wharton School, allows students to simultaneously earn a Bachelor of Science degree in Economics as well as a Bachelor of Science degree in Engineering. SEAS also offers several masters programs, which include: Executive Master’s in Technology Management, Master of Biotechnology, Master of Computer and Information Technology, Master of Computer and Information Science and a Master of Science in Engineering in Telecommunications and Networking.

    History

    The study of engineering at The University of Pennsylvania can be traced back to 1850 when the University trustees adopted a resolution providing for a professorship of “Chemistry as Applied to the Arts”. In 1852, the study of engineering was further formalized with the establishment of the School of Mines, Arts and Manufactures. The first Professor of Civil and Mining Engineering was appointed in 1852. The first graduate of the school received his Bachelor of Science degree in 1854. Since that time, the school has grown to six departments. In 1973, the school was renamed as the School of Engineering and Applied Science.

    The early growth of the school benefited from the generosity of two Philadelphians: John Henry Towne and Alfred Fitler Moore. Towne, a mechanical engineer and railroad developer, bequeathed the school a gift of $500,000 upon his death in 1875. The main administration building for the school still bears his name. Moore was a successful entrepreneur who made his fortune manufacturing telegraph cable. A 1923 gift from Moore established the Moore School of Electrical Engineering, which is the birthplace of the first electronic general-purpose Turing-complete digital computer, ENIAC, in 1946.

    During the latter half of the 20th century the school continued to break new ground. In 1958, Barbara G. Mandell became the first woman to enroll as an undergraduate in the School of Engineering. In 1965, the university acquired two sites that were formerly used as U.S. Army Nike Missile Base (PH 82L and PH 82R) and created the Valley Forge Research Center. In 1976, the Management and Technology Program was created. In 1990, a Bachelor of Applied Science in Biomedical Science and Bachelor of Applied Science in Environmental Science were first offered, followed by a master’s degree in Biotechnology in 1997.

    The school continues to expand with the addition of the Melvin and Claire Levine Hall for computer science in 2003, Skirkanich Hall for Bioengineering in 2006, and the Krishna P. Singh Center for Nanotechnology in 2013.

    Academics

    Penn’s School of Engineering and Applied Science is organized into six departments:

    Bioengineering
    Chemical and Biomolecular Engineering
    Computer and Information Science
    Electrical and Systems Engineering
    Materials Science and Engineering
    Mechanical Engineering and Applied Mechanics

    The school’s Department of Bioengineering, originally named Biomedical Electronic Engineering, consistently garners a top-ten ranking at both the undergraduate and graduate level from U.S. News & World Report. The department also houses the George H. Stephenson Foundation Educational Laboratory & Bio-MakerSpace (aka Biomakerspace) for training undergraduate through PhD students. It is Philadelphia’s and Penn’s only Bio-MakerSpace and it is open to the Penn community, encouraging a free flow of ideas, creativity, and entrepreneurship between Bioengineering students and students throughout the university.

    Founded in 1893, the Department of Chemical and Biomolecular Engineering is “America’s oldest continuously operating degree-granting program in chemical engineering.”

    The Department of Electrical and Systems Engineering is recognized for its research in electroscience, systems science and network systems and telecommunications.

    Originally established in 1946 as the School of Metallurgical Engineering, the Materials Science and Engineering Department “includes cutting edge programs in nanoscience and nanotechnology, biomaterials, ceramics, polymers, and metals.”

    The Department of Mechanical Engineering and Applied Mechanics draws its roots from the Department of Mechanical and Electrical Engineering, which was established in 1876.

    Each department houses one or more degree programs. The Chemical and Biomolecular Engineering, Materials Science and Engineering, and Mechanical Engineering and Applied Mechanics departments each house a single degree program.

    Bioengineering houses two programs (both a Bachelor of Science in Engineering degree as well as a Bachelor of Applied Science degree). Electrical and Systems Engineering offers four Bachelor of Science in Engineering programs: Electrical Engineering, Systems Engineering, Computer Engineering, and the Networked & Social Systems Engineering, the latter two of which are co-housed with Computer and Information Science (CIS). The CIS department, like Bioengineering, offers Computer and Information Science programs under both bachelor programs. CIS also houses Digital Media Design, a program jointly operated with PennDesign.

    Research

    Penn’s School of Engineering and Applied Science is a research institution. SEAS research strives to advance science and engineering and to achieve a positive impact on society.

    U Penn campus

    Academic life at University of Pennsylvania is unparalleled, with 100 countries and every U.S. state represented in one of the Ivy League’s most diverse student bodies. Consistently ranked among the top 10 universities in the country, Penn enrolls 10,000 undergraduate students and welcomes an additional 10,000 students to our world-renowned graduate and professional schools.

    Penn’s award-winning educators and scholars encourage students to pursue inquiry and discovery, follow their passions, and address the world’s most challenging problems through an interdisciplinary approach.

    The University of Pennsylvania is a private Ivy League research university in Philadelphia, Pennsylvania. The university claims a founding date of 1740 and is one of the nine colonial colleges chartered prior to the U.S. Declaration of Independence. Benjamin Franklin, Penn’s founder and first president, advocated an educational program that trained leaders in commerce, government, and public service, similar to a modern liberal arts curriculum.

    Penn has four undergraduate schools as well as twelve graduate and professional schools. Schools enrolling undergraduates include the College of Arts and Sciences; the School of Engineering and Applied Science; the Wharton School; and the School of Nursing. Penn’s “One University Policy” allows students to enroll in classes in any of Penn’s twelve schools. Among its highly ranked graduate and professional schools are a law school whose first professor wrote the first draft of the United States Constitution, the first school of medicine in North America (Perelman School of Medicine, 1765), and the first collegiate business school (Wharton School, 1881).

    Penn is also home to the first “student union” building and organization (Houston Hall, 1896), the first Catholic student club in North America (Newman Center, 1893), the first double-decker college football stadium (Franklin Field, 1924 when second deck was constructed), and Morris Arboretum, the official arboretum of the Commonwealth of Pennsylvania. The first general-purpose electronic computer (ENIAC) was developed at Penn and formally dedicated in 1946. In 2019, the university had an endowment of $14.65 billion, the sixth-largest endowment of all universities in the United States, as well as a research budget of $1.02 billion. The university’s athletics program, the Quakers, fields varsity teams in 33 sports as a member of the NCAA Division I Ivy League conference.

    As of 2018, distinguished alumni and/or Trustees include three U.S. Supreme Court justices; 32 U.S. senators; 46 U.S. governors; 163 members of the U.S. House of Representatives; eight signers of the Declaration of Independence and seven signers of the U.S. Constitution (four of whom signed both representing two-thirds of the six people who signed both); 24 members of the Continental Congress; 14 foreign heads of state and two presidents of the United States, including Donald Trump. As of October 2019, 36 Nobel laureates; 80 members of the American Academy of Arts and Sciences; 64 billionaires; 29 Rhodes Scholars; 15 Marshall Scholars and 16 Pulitzer Prize winners have been affiliated with the university.

    History

    The University of Pennsylvania considers itself the fourth-oldest institution of higher education in the United States, though this is contested by Princeton University and Columbia University. The university also considers itself as the first university in the United States with both undergraduate and graduate studies.

    In 1740, a group of Philadelphians joined together to erect a great preaching hall for the traveling evangelist George Whitefield, who toured the American colonies delivering open-air sermons. The building was designed and built by Edmund Woolley and was the largest building in the city at the time, drawing thousands of people the first time it was preached in. It was initially planned to serve as a charity school as well, but a lack of funds forced plans for the chapel and school to be suspended. According to Franklin’s autobiography, it was in 1743 when he first had the idea to establish an academy, “thinking the Rev. Richard Peters a fit person to superintend such an institution”. However, Peters declined a casual inquiry from Franklin and nothing further was done for another six years. In the fall of 1749, now more eager to create a school to educate future generations, Benjamin Franklin circulated a pamphlet titled Proposals Relating to the Education of Youth in Pensilvania, his vision for what he called a “Public Academy of Philadelphia”. Unlike the other colonial colleges that existed in 1749—Harvard University, William & Mary, Yale Unversity, and The College of New Jersey—Franklin’s new school would not focus merely on education for the clergy. He advocated an innovative concept of higher education, one which would teach both the ornamental knowledge of the arts and the practical skills necessary for making a living and doing public service. The proposed program of study could have become the nation’s first modern liberal arts curriculum, although it was never implemented because Anglican priest William Smith (1727-1803), who became the first provost, and other trustees strongly preferred the traditional curriculum.

    Franklin assembled a board of trustees from among the leading citizens of Philadelphia, the first such non-sectarian board in America. At the first meeting of the 24 members of the board of trustees on November 13, 1749, the issue of where to locate the school was a prime concern. Although a lot across Sixth Street from the old Pennsylvania State House (later renamed and famously known since 1776 as “Independence Hall”), was offered without cost by James Logan, its owner, the trustees realized that the building erected in 1740, which was still vacant, would be an even better site. The original sponsors of the dormant building still owed considerable construction debts and asked Franklin’s group to assume their debts and, accordingly, their inactive trusts. On February 1, 1750, the new board took over the building and trusts of the old board. On August 13, 1751, the “Academy of Philadelphia”, using the great hall at 4th and Arch Streets, took in its first secondary students. A charity school also was chartered on July 13, 1753 by the intentions of the original “New Building” donors, although it lasted only a few years. On June 16, 1755, the “College of Philadelphia” was chartered, paving the way for the addition of undergraduate instruction. All three schools shared the same board of trustees and were considered to be part of the same institution. The first commencement exercises were held on May 17, 1757.

    The institution of higher learning was known as the College of Philadelphia from 1755 to 1779. In 1779, not trusting then-provost the Reverend William Smith’s “Loyalist” tendencies, the revolutionary State Legislature created a University of the State of Pennsylvania. The result was a schism, with Smith continuing to operate an attenuated version of the College of Philadelphia. In 1791, the legislature issued a new charter, merging the two institutions into a new University of Pennsylvania with twelve men from each institution on the new board of trustees.

    Penn has three claims to being the first university in the United States, according to university archives director Mark Frazier Lloyd: the 1765 founding of the first medical school in America made Penn the first institution to offer both “undergraduate” and professional education; the 1779 charter made it the first American institution of higher learning to take the name of “University”; and existing colleges were established as seminaries (although, as detailed earlier, Penn adopted a traditional seminary curriculum as well).

    After being located in downtown Philadelphia for more than a century, the campus was moved across the Schuylkill River to property purchased from the Blockley Almshouse in West Philadelphia in 1872, where it has since remained in an area now known as University City. Although Penn began operating as an academy or secondary school in 1751 and obtained its collegiate charter in 1755, it initially designated 1750 as its founding date; this is the year that appears on the first iteration of the university seal. Sometime later in its early history, Penn began to consider 1749 as its founding date and this year was referenced for over a century, including at the centennial celebration in 1849. In 1899, the board of trustees voted to adjust the founding date earlier again, this time to 1740, the date of “the creation of the earliest of the many educational trusts the University has taken upon itself”. The board of trustees voted in response to a three-year campaign by Penn’s General Alumni Society to retroactively revise the university’s founding date to appear older than Princeton University, which had been chartered in 1746.

    Research, innovations and discoveries

    Penn is classified as an “R1” doctoral university: “Highest research activity.” Its economic impact on the Commonwealth of Pennsylvania for 2015 amounted to $14.3 billion. Penn’s research expenditures in the 2018 fiscal year were $1.442 billion, the fourth largest in the U.S. In fiscal year 2019 Penn received $582.3 million in funding from the National Institutes of Health.

    In line with its well-known interdisciplinary tradition, Penn’s research centers often span two or more disciplines. In the 2010–2011 academic year alone, five interdisciplinary research centers were created or substantially expanded; these include the Center for Health-care Financing; the Center for Global Women’s Health at the Nursing School; the $13 million Morris Arboretum’s Horticulture Center; the $15 million Jay H. Baker Retailing Center at Wharton; and the $13 million Translational Research Center at Penn Medicine. With these additions, Penn now counts 165 research centers hosting a research community of over 4,300 faculty and over 1,100 postdoctoral fellows, 5,500 academic support staff and graduate student trainees. To further assist the advancement of interdisciplinary research President Amy Gutmann established the “Penn Integrates Knowledge” title awarded to selected Penn professors “whose research and teaching exemplify the integration of knowledge”. These professors hold endowed professorships and joint appointments between Penn’s schools.

    Penn is also among the most prolific producers of doctoral students. With 487 PhDs awarded in 2009, Penn ranks third in the Ivy League, only behind Columbia University and Cornell University (Harvard University did not report data). It also has one of the highest numbers of post-doctoral appointees (933 in number for 2004–2007), ranking third in the Ivy League (behind Harvard and Yale University) and tenth nationally.

    In most disciplines Penn professors’ productivity is among the highest in the nation and first in the fields of epidemiology, business, communication studies, comparative literature, languages, information science, criminal justice and criminology, social sciences and sociology. According to the National Research Council nearly three-quarters of Penn’s 41 assessed programs were placed in ranges including the top 10 rankings in their fields, with more than half of these in ranges including the top five rankings in these fields.

    Penn’s research tradition has historically been complemented by innovations that shaped higher education. In addition to establishing the first medical school; the first university teaching hospital; the first business school; and the first student union Penn was also the cradle of other significant developments. In 1852, Penn Law was the first law school in the nation to publish a law journal still in existence (then called The American Law Register, now the Penn Law Review, one of the most cited law journals in the world). Under the deanship of William Draper Lewis, the law school was also one of the first schools to emphasize legal teaching by full-time professors instead of practitioners, a system that is still followed today. The Wharton School was home to several pioneering developments in business education. It established the first research center in a business school in 1921 and the first center for entrepreneurship center in 1973 and it regularly introduced novel curricula for which BusinessWeek wrote, “Wharton is on the crest of a wave of reinvention and change in management education”.

    Several major scientific discoveries have also taken place at Penn. The university is probably best known as the place where the first general-purpose electronic computer (ENIAC) was born in 1946 at the Moore School of Electrical Engineering.

    ENIAC UPenn

    It was here also where the world’s first spelling and grammar checkers were created, as well as the popular COBOL programming language. Penn can also boast some of the most important discoveries in the field of medicine. The dialysis machine used as an artificial replacement for lost kidney function was conceived and devised out of a pressure cooker by William Inouye while he was still a student at Penn Med; the Rubella and Hepatitis B vaccines were developed at Penn; the discovery of cancer’s link with genes; cognitive therapy; Retin-A (the cream used to treat acne), Resistin; the Philadelphia gene (linked to chronic myelogenous leukemia) and the technology behind PET Scans were all discovered by Penn Med researchers. More recent gene research has led to the discovery of the genes for fragile X syndrome, the most common form of inherited mental retardation; spinal and bulbar muscular atrophy, a disorder marked by progressive muscle wasting; and Charcot–Marie–Tooth disease, a progressive neurodegenerative disease that affects the hands, feet and limbs.

    Conductive polymer was also developed at Penn by Alan J. Heeger, Alan MacDiarmid and Hideki Shirakawa, an invention that earned them the Nobel Prize in Chemistry. On faculty since 1965, Ralph L. Brinster developed the scientific basis for in vitro fertilization and the transgenic mouse at Penn and was awarded the National Medal of Science in 2010. The theory of superconductivity was also partly developed at Penn, by then-faculty member John Robert Schrieffer (along with John Bardeen and Leon Cooper). The university has also contributed major advancements in the fields of economics and management. Among the many discoveries are conjoint analysis, widely used as a predictive tool especially in market research; Simon Kuznets’s method of measuring Gross National Product; the Penn effect (the observation that consumer price levels in richer countries are systematically higher than in poorer ones) and the “Wharton Model” developed by Nobel-laureate Lawrence Klein to measure and forecast economic activity. The idea behind Health Maintenance Organizations also belonged to Penn professor Robert Eilers, who put it into practice during then-President Nixon’s health reform in the 1970s.

    International partnerships

    Students can study abroad for a semester or a year at partner institutions such as the London School of Economics(UK), University of Barcelona [Universitat de Barcelona](ES), Paris Institute of Political Studies [Institut d’études politiques de Paris](FR), University of Queensland(AU), University College London(UK), King’s College London(UK), Hebrew University of Jerusalem(IL) and University of Warwick(UK).

     
  • richardmitnick 7:54 am on October 18, 2022 Permalink | Reply
    Tags: "FETs": Field-effect transistors, "The successful integration of a sub-0.5nm dielectric with 2D semiconductors", , , Peking University [北京大学](CN), ,   

    From The University of Texas-Austin And Peking University [北京大学](CN) Via “TechXplore” at “Science X”: “The successful integration of a sub-0.5nm dielectric with 2D semiconductors” 

    From The University of Texas-Austin

    And

    Peking University[北京大学](CN)

    Via


    TechXplore at Science X

    10.17.22
    Ingrid Fadelli

    1
    Synthesis and properties of the single-crystalline native oxide dielectric β-Bi2SeO5. a, Diagram of the UV-assisted intercalative oxidation of 2D Bi2O2Se for single-crystalline native oxide dielectric β-Bi2SeO5. b, Wafer-scale area-selective oxidation for Bi2O2Se/β-Bi2SeO5 heterostructure. c, Atomic structure of Bi2O2Se/β-Bi2SeO5 heterostructure at the intercalative oxidation frontier. d, Comparison of single-crystalline β-Bi2SeO5 and common dielectrics in terms of EOT or ECT (effective capacitance thickness) versus leakage current at 1 V gate voltage. Credit: Zhang et al.

    Field-effect transistors (FETs) are transistors in which the resistance of most of the electrical current can be controlled by a transverse electric field. Over the past decade or so, these devices have proved to be very valuable solutions for controlling the flow of current in semiconductors.

    To further develop FETs, electronics engineers worldwide have recently been trying to reduce their size. While these down-scaling efforts have been found to increase the device’s speed and lower the power consumption, they are also associated with short-channel effects (i.e., unfavorable effects that occur when an FET’s channel length is approximately equal to the space charge regions of source and drain junctions within its substrate).

    These undesirable effects, which include barrier lowering and velocity saturation, could be suppressed by using 2D semiconductor channels with high carrier mobilities and ultrathin high-k dielectrics (i.e., materials with high dielectric constants). Integrating 2D semiconductors with dielectrics with similar oxide thicknesses has been found to be highly challenging.

    Researchers at Peking University and University of Texas at Austin have recently demonstrated the successful integration of a sub-0.5nm dielectric layer with 2D semiconductor-based transistors. Their design, introduced in a paper published in Nature Electronics [below], could ultimately pave the way towards the development of smaller, faster, and more efficient FETs.

    “Previously [Nature Electronics (below)] we have synthesized a poly-crystalline high-κ (dielectric constant) native oxide dielectric of 2D Bi2O2Se and found that its equivalent oxide thickness (EOT) can be scaled down to 0.9 nm, but the leakage current exceeds the low-power limit,” Hailin Peng, one of the researchers who carried out the study, told TechXplore. “Inspired by the layered crystal structure of 2D Bi2O2Se and the intercalation of 2D materials, we designed an intercalative oxidation process to retain the lattice framework of the precursor, to obtain a single-crystalline native oxide with better insulativity for further downscaling.”

    To integrate their dielectric with 2D semiconductors, Peng and his colleagues used a process called UV-assisted intercalative oxidation. Firstly, they decomposed oxygen molecules contained in the air into atomic oxygen using 185 nm ultraviolet (UV) rays emitted from a low-pressure mercury lamp.

    Subsequently, they used the atomic oxygen to oxidize the Se2- layer in the 2D semiconductor Bi2O2Se between the two [Bi2O2]n2n+ layers, without affecting the properties of the [Bi2O2]n2n+ layers. This process led to the formation of a new ‘layered phase,” which inherited the single-crystalline [Bi2O2]n2n+ structure of the original Bi2O2Se sample.

    “The as-synthesized oxide is further confirmed to be a single-crystalline native dielectric and named β-Bi2SeO5,” Peng explained. “The single-crystalline native oxide β-Bi2SeO5 has a thickness-independent high dielectric constant of about 22, ultraflat lattice-matched interface, and excellent insulativity. Even when scaled down to 2.3 nm and the EOT (equivalent oxide thickness, 3.9×thickness/dielectric constant) is as low as 0.41 nm, the leakage current at 1 V gate voltage is still below the low-power limit (0.015 A/cm2), meeting the industrial requirements of dielectrics in next-generation transistors.”

    The initial tests carried out by Peng and his colleagues yielded interesting results. Overall, their findings suggest β-Bi2SeO5, the material they created, could be promising for developing an ultrathin high-κ (dielectric constant) gate dielectric in 2D transistors.

    “The most notable achievement of our study was the successful integration of sub-0.5-nm-EOT dielectrics in top-gated 2D transistors, which meets the benchmarks of dielectric in the 2021 International Roadmap for Devices and Systems,” Peng said. “Thus, one of the challenges for 2D electronics, the integration with sub-0.5-nm-EOT ultrathin high-κ dielectric, has been overcome.”

    This team of researchers demonstrated the possibility of integrating 2D semiconductors with high-k dielectrics. In the future, the material that they created and the method introduced in their paper could be used to create smaller and highly-performing FETs that are not adversely impacted by short-channel effects.

    “We will now further investigate the compatibility of β-Bi2SeO5 with other common 2D materials and metal electrodes,” Peng added. “In addition, a large-scale transfer process of Bi2SeO5 or its precursor Bi2O2Se is also desired for the integration of this ultrathin high-κ dielectric with a broad range of 2D materials.”

    Science papers:
    Nature Electronics
    Nature Electronics (2020)

    See the full article here.

    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition

    Peking University[北京大学](CN) is a public research university in Beijing, China. The university is funded by the Ministry of Education.

    Peking University was established as the Imperial University of Peking in 1898 when it received its royal charter by the Guangxu Emperor. A successor of the older Guozijian Imperial College, the university’s romanized name ‘Peking’ retains the older transliteration of ‘Beijing’ that has been superseded in most other contexts. Perennially ranked as one of the top academic institutions in China and the world, as of 2021 Peking University was ranked 16th globally and 1st in the Asia-Pacific & emerging countries by Times Higher Education, while as of 2022 it was ranked 12th globally and 1st in China by QS World University Rankings.

    Throughout its history, Peking University has had an important role “at the center of major intellectual movements” in China. Abolished of its status as a royal institution after the fall of the Qing dynasty and the Xinhai Revolution; from the early 1920s, the university became a center for China’s emerging, progressive, and republican movements. Faculty and students held important roles in originating the New Culture Movement, the May Fourth Movement protests, and other significant cultural and sociopolitical events, to the extent that the university’s history has been closely tied to that of modern China. Peking University has educated and hosted many prominent modern Chinese figures, including Mao Zedong, Lu Xun, Gu Hongming, Hu Shih, Mao Dun, Li Dazhao, Chen Duxiu, and current Premier Li Keqiang.

    Peking University is a member of the C9 League, Double First Class University Plan, former Project 985 and former Project 211. The university library contains over 8 million volumes. The university also operates the PKU Hall, a professional performing arts center, and the Arthur M. Sackler Museum of Arts and Archaeology. The university is also renowned for its campus grounds and the beauty of its traditional Chinese architecture. Additionally, it hosts one of the only undergraduate liberal arts colleges in Asia, and is a Class A institution under the Chinese Double First Class University program. Peking University’s staff include 76 members of the Chinese Academy of Sciences, 19 members of the Chinese Academy of Engineering and 25 members of the World Academy of Sciences.

    In 2000, Beijing Medical University was merged back into Peking University and became the Peking University Health Science Campus. Beijing Medical University, which used to be Medical School of Peking University, was separated from Peking University in 1952. Peking University now has eight affiliated hospitals and 12 teaching hospitals.

    In 2001, Peking University established the Yuanpei Program. It was formalized in 2007 as the Yuanpei College, named in honor of the highly respected former university president Cai Yuanpei. The college hosts an elite undergraduate liberal arts program that allows students to freely choose specializations. In the same year, Peking University set up a satellite campus for graduate students in Shenzhen. The university’s second business school, Peking University HSBC Business School was launched on the Shenzhen campus in 2004.

    In 2014, Peking University established the Yenching Academy, a fully funded global fellowship program designed “to cultivate leaders who will advocate for global progress and cultural understanding.”

    In October 2015, Peking University alumni Professor Tu Youyou was awarded the Nobel Prize in Physiology or Medicine for her discovery of artemisinin. Having saved millions of lives, artemisinin has made significant contributions to global health in regard to the fight against malaria.

    In May 2016, the Peking University Department of Psychology was renamed as Peking University School of Psychological and Cognitive Sciences. On July 5, Peking University and Moscow State University signed the Joint Declaration on the Establishment of the Comprehensive University Alliance between the People’s Republic of China and the Russian Federation, proposing the establishment of the China-Russia Comprehensive University Alliance. On August 29, Peking University signed a memorandum with the Shenzhen Municipal People’s Government to jointly open Peking University Shenzhen Campus. On September 20, Peking University Institute of Humanities and Social Sciences was officially inaugurated.

    On February 20, 2017, the University officially signed a contract with the British Open University to establish the Oxford Campus of Peking University HSBC Business School, Peking University Oxford Center and Shenzhen Oxford Innovation Center. In March, the National Engineering Laboratory for Big Data Analysis and Application Technology was unveiled. In September, Peking University was selected as a national “double first-class” university. On December 13, Peking University School of Advanced Agricultural Sciences was established.

    On May 4, 2018, Peking University held its 120th anniversary meeting at the Khoo Teck Puat Gymnasium. On October 24th, Peking University led the formation of the medical “Double First-Class” (i.e. world-class universities and first-class disciplines) Construction Alliance, which is the first unofficial non-profit medical higher education and medical discipline construction collaboration organization.

    In February 2019, Peking University and the University of Hong Kong signed a cooperation agreement to cooperate in the dual bachelor’s degree program in law; in the same month, Peking University and the Chinese University of Hong Kong signed a cooperation agreement to jointly organize undergraduate double-degree programs of Linguistics and Chinese Language and Literature. In December, it joined the “Belt and Road” Think Tank Cooperation Alliance as a governing unit.

    In May 2019, Peking University and Beijing Geely University signed an agreement. Peking University will build a new campus on the original site of Geely Institute in Changping.

    Several rankings have placed Peking University among the top universities in mainland China. In 2015, the Chinese University Alumni Association in partnership with China Education Center considered it first among all Chinese universities.

    Typically, Peking University is consistently ranked among the top universities in the Asia-Pacific and the world according to major international university rankings. The joint THE-QS World University Rankings 2006 ranked Peking University 1st in the Asia & Oceania region and 14th in the world. In 2014, the U.S. News & World Report ranked Peking University 39th in the world, 2nd in the Asia-Pacific and 1st in China. Peking had topped the newly launched Times Higher Education BRICS & Emerging Economies since its inception in 2014.

    The 2023 QS World University Rankings ranked Peking University 12th in the world , 2nd in Asia and first in China. As of 2022, the Times Higher Education World University Rankings ranked Peking University 16th in the world and 1st in China & the Asia-Pacific, with its teaching and research performance indicators placed at 4th and 9th in the world respectively. Peking University was also ranked 15th in the world and 1st in the Asia-Pacific in The Three University Missions Ranking. Academic Ranking of World Universities, also known as the Shanghai Ranking, placed Peking University 34th in the world, 3rd in Asia, and 2nd in China. The U.S. News & World Report ranked Peking University 45th in the world, 5th in Asia and 2nd in China.

    In the QS Graduate Employability Rankings 2017, an annual ranking of university graduates’ employability, Peking University was ranked 11th in the world and 2nd in Asia. In 2019, the QS World University Rankings ranked the university as one of the world’s top 20 universities for academic reputation where, it ranked 16 globally, and top 10 in the world and first in the Asia-Pacific for employer reputation. Since 2017, Peking has been placed among the world’s top 20 most reputable universities by the Times Higher Education World Reputation Rankings, where it ranked 15 globally in 2021.

    Research Performance and Subjects Rankings

    The 2020 CWTS Leiden Ranking ranked Peking University at 8th in the world based on their publications for the time period 2015–2018. For the high quality of research in natural science and life science, Peking University ranked 10th among the leading institutions, and 6th among the leading universities globally in the Nature Index 2022 Annual Tables by Nature Research. In 2020, it ranked 13th among the universities around the world by SCImago Institutions Rankings.

    As of 2021, it was ranked 8th globally in “Education”, 12th in “Engineering and Technology”, 15th in “Physical Science”, 17th in “Computer Science”, 18th in “Social Science”, 19th in “Life Science”, 21st in “Arts and Humanities”, 22nd in “Business and Economics”, 22nd in “Clinical, pre-clinical and Health” and 45th in “Psychology” by the Times Higher Education Rankings by Subjects.

    University of Texas-Austin

    University of Texas-Austin campus

    The University of Texas-Austin is a public research university in Austin, Texas and the flagship institution of the University of Texas System. Founded in 1883, the University of Texas was inducted into the Association of American Universities in 1929, becoming only the third university in the American South to be elected. The institution has the nation’s seventh-largest single-campus enrollment, with over 50,000 undergraduate and graduate students and over 24,000 faculty and staff.

    A Public Ivy, it is a major center for academic research. The university houses seven museums and seventeen libraries, including the LBJ Presidential Library and the Blanton Museum of Art, and operates various auxiliary research facilities, such as the J. J. Pickle Research Campus and the McDonald Observatory. As of November 2020, 13 Nobel Prize winners, four Pulitzer Prize winners, two Turing Award winners, two Fields medalists, two Wolf Prize winners, and two Abel prize winners have been affiliated with the school as alumni, faculty members or researchers. The university has also been affiliated with three Primetime Emmy Award winners, and has produced a total of 143 Olympic medalists.

    Student-athletes compete as the Texas Longhorns and are members of the Big 12 Conference. Its Longhorn Network is the only sports network featuring the college sports of a single university. The Longhorns have won four NCAA Division I National Football Championships, six NCAA Division I National Baseball Championships, thirteen NCAA Division I National Men’s Swimming and Diving Championships, and has claimed more titles in men’s and women’s sports than any other school in the Big 12 since the league was founded in 1996.

    Establishment

    The first mention of a public university in Texas can be traced to the 1827 constitution for the Mexican state of Coahuila y Tejas. Although Title 6, Article 217 of the Constitution promised to establish public education in the arts and sciences, no action was taken by the Mexican government. After Texas obtained its independence from Mexico in 1836, the Texas Congress adopted the Constitution of the Republic, which, under Section 5 of its General Provisions, stated “It shall be the duty of Congress, as soon as circumstances will permit, to provide, by law, a general system of education.”

    On April 18, 1838, “An Act to Establish the University of Texas” was referred to a special committee of the Texas Congress, but was not reported back for further action. On January 26, 1839, the Texas Congress agreed to set aside fifty leagues of land—approximately 288,000 acres (117,000 ha)—towards the establishment of a publicly funded university. In addition, 40 acres (16 ha) in the new capital of Austin were reserved and designated “College Hill”. (The term “Forty Acres” is colloquially used to refer to the University as a whole. The original 40 acres is the area from Guadalupe to Speedway and 21st Street to 24th Street.)

    In 1845, Texas was annexed into the United States. The state’s Constitution of 1845 failed to mention higher education. On February 11, 1858, the Seventh Texas Legislature approved O.B. 102, an act to establish the University of Texas, which set aside $100,000 in United States bonds toward construction of the state’s first publicly funded university (the $100,000 was an allocation from the $10 million the state received pursuant to the Compromise of 1850 and Texas’s relinquishing claims to lands outside its present boundaries). The legislature also designated land reserved for the encouragement of railroad construction toward the university’s endowment. On January 31, 1860, the state legislature, wanting to avoid raising taxes, passed an act authorizing the money set aside for the University of Texas to be used for frontier defense in west Texas to protect settlers from Indian attacks.

    Texas’s secession from the Union and the American Civil War delayed repayment of the borrowed monies. At the end of the Civil War in 1865, The University of Texas’s endowment was just over $16,000 in warrants and nothing substantive had been done to organize the university’s operations. This effort to establish a University was again mandated by Article 7, Section 10 of the Texas Constitution of 1876 which directed the legislature to “establish, organize and provide for the maintenance, support and direction of a university of the first class, to be located by a vote of the people of this State, and styled “The University of Texas”.

    Additionally, Article 7, Section 11 of the 1876 Constitution established the Permanent University Fund, a sovereign wealth fund managed by the Board of Regents of the University of Texas and dedicated to the maintenance of the university. Because some state legislators perceived an extravagance in the construction of academic buildings of other universities, Article 7, Section 14 of the Constitution expressly prohibited the legislature from using the state’s general revenue to fund construction of university buildings. Funds for constructing university buildings had to come from the university’s endowment or from private gifts to the university, but the university’s operating expenses could come from the state’s general revenues.

    The 1876 Constitution also revoked the endowment of the railroad lands of the Act of 1858, but dedicated 1,000,000 acres (400,000 ha) of land, along with other property appropriated for the university, to the Permanent University Fund. This was greatly to the detriment of the university as the lands the Constitution of 1876 granted the university represented less than 5% of the value of the lands granted to the university under the Act of 1858 (the lands close to the railroads were quite valuable, while the lands granted the university were in far west Texas, distant from sources of transportation and water). The more valuable lands reverted to the fund to support general education in the state (the Special School Fund).

    On April 10, 1883, the legislature supplemented the Permanent University Fund with another 1,000,000 acres (400,000 ha) of land in west Texas granted to the Texas and Pacific Railroad but returned to the state as seemingly too worthless to even survey. The legislature additionally appropriated $256,272.57 to repay the funds taken from the university in 1860 to pay for frontier defense and for transfers to the state’s General Fund in 1861 and 1862. The 1883 grant of land increased the land in the Permanent University Fund to almost 2.2 million acres. Under the Act of 1858, the university was entitled to just over 1,000 acres (400 ha) of land for every mile of railroad built in the state. Had the 1876 Constitution not revoked the original 1858 grant of land, by 1883, the university lands would have totaled 3.2 million acres, so the 1883 grant was to restore lands taken from the university by the 1876 Constitution, not an act of munificence.

    On March 30, 1881, the legislature set forth the university’s structure and organization and called for an election to establish its location. By popular election on September 6, 1881, Austin (with 30,913 votes) was chosen as the site. Galveston, having come in second in the election (with 20,741 votes), was designated the location of the medical department (Houston was third with 12,586 votes). On November 17, 1882, on the original “College Hill,” an official ceremony commemorated the laying of the cornerstone of the Old Main building. University President Ashbel Smith, presiding over the ceremony, prophetically proclaimed “Texas holds embedded in its earth rocks and minerals which now lie idle because unknown, resources of incalculable industrial utility, of wealth and power. Smite the earth, smite the rocks with the rod of knowledge and fountains of unstinted wealth will gush forth.” The University of Texas officially opened its doors on September 15, 1883.

    Expansion and growth

    In 1890, George Washington Brackenridge donated $18,000 for the construction of a three-story brick mess hall known as Brackenridge Hall (affectionately known as “B.Hall”), one of the university’s most storied buildings and one that played an important place in university life until its demolition in 1952.

    The old Victorian-Gothic Main Building served as the central point of the campus’s 40-acre (16 ha) site, and was used for nearly all purposes. But by the 1930s, discussions arose about the need for new library space, and the Main Building was razed in 1934 over the objections of many students and faculty. The modern-day tower and Main Building were constructed in its place.

    In 1910, George Washington Brackenridge again displayed his philanthropy, this time donating 500 acres (200 ha) on the Colorado River to the university. A vote by the regents to move the campus to the donated land was met with outrage, and the land has only been used for auxiliary purposes such as graduate student housing. Part of the tract was sold in the late-1990s for luxury housing, and there are controversial proposals to sell the remainder of the tract. The Brackenridge Field Laboratory was established on 82 acres (33 ha) of the land in 1967.

    In 1916, Gov. James E. Ferguson became involved in a serious quarrel with the University of Texas. The controversy grew out of the board of regents’ refusal to remove certain faculty members whom the governor found objectionable. When Ferguson found he could not have his way, he vetoed practically the entire appropriation for the university. Without sufficient funding, the university would have been forced to close its doors. In the middle of the controversy, Ferguson’s critics brought to light a number of irregularities on the part of the governor. Eventually, the Texas House of Representatives prepared 21 charges against Ferguson, and the Senate convicted him on 10 of them, including misapplication of public funds and receiving $156,000 from an unnamed source. The Texas Senate removed Ferguson as governor and declared him ineligible to hold office.

    In 1921, the legislature appropriated $1.35 million for the purchase of land next to the main campus. However, expansion was hampered by the restriction against using state revenues to fund construction of university buildings as set forth in Article 7, Section 14 of the Constitution. With the completion of Santa Rita No. 1 well and the discovery of oil on university-owned lands in 1923, the university added significantly to its Permanent University Fund. The additional income from Permanent University Fund investments allowed for bond issues in 1931 and 1947, which allowed the legislature to address funding for the university along with the Agricultural and Mechanical College (now known as Texas A&M University). With sufficient funds to finance construction on both campuses, on April 8, 1931, the Forty Second Legislature passed H.B. 368. which dedicated the Agricultural and Mechanical College a 1/3 interest in the Available University Fund, the annual income from Permanent University Fund investments.

    The University of Texas was inducted into The Association of American Universities in 1929. During World War II, the University of Texas was one of 131 colleges and universities nationally that took part in the V-12 Navy College Training Program which offered students a path to a Navy commission.

    In 1950, following Sweatt v. Painter, the University of Texas was the first major university in the South to accept an African-American student. John S. Chase went on to become the first licensed African-American architect in Texas.

    In the fall of 1956, the first black students entered the university’s undergraduate class. Black students were permitted to live in campus dorms, but were barred from campus cafeterias. The University of Texas integrated its facilities and desegregated its dorms in 1965. UT, which had had an open admissions policy, adopted standardized testing for admissions in the mid-1950s at least in part as a conscious strategy to minimize the number of Black undergraduates, given that they were no longer able to simply bar their entry after the Brown decision.

    Following growth in enrollment after World War II, the university unveiled an ambitious master plan in 1960 designed for “10 years of growth” that was intended to “boost the University of Texas into the ranks of the top state universities in the nation.” In 1965, the Texas Legislature granted the university Board of Regents to use eminent domain to purchase additional properties surrounding the original 40 acres (160,000 m^2). The university began buying parcels of land to the north, south, and east of the existing campus, particularly in the Blackland neighborhood to the east and the Brackenridge tract to the southeast, in hopes of using the land to relocate the university’s intramural fields, baseball field, tennis courts, and parking lots.

    On March 6, 1967, the Sixtieth Texas Legislature changed the university’s official name from “The University of Texas” to “The University of Texas at Austin” to reflect the growth of the University of Texas System.

    Recent history

    The first presidential library on a university campus was dedicated on May 22, 1971, with former President Johnson, Lady Bird Johnson and then-President Richard Nixon in attendance. Constructed on the eastern side of the main campus, the Lyndon Baines Johnson Library and Museum is one of 13 presidential libraries administered by the National Archives and Records Administration.

    A statue of Martin Luther King Jr. was unveiled on campus in 1999 and subsequently vandalized. By 2004, John Butler, a professor at the McCombs School of Business suggested moving it to Morehouse College, a historically black college, “a place where he is loved”.

    The University of Texas-Austin has experienced a wave of new construction recently with several significant buildings. On April 30, 2006, the school opened the Blanton Museum of Art. In August 2008, the AT&T Executive Education and Conference Center opened, with the hotel and conference center forming part of a new gateway to the university. Also in 2008, Darrell K Royal-Texas Memorial Stadium was expanded to a seating capacity of 100,119, making it the largest stadium (by capacity) in the state of Texas at the time.

    On January 19, 2011, the university announced the creation of a 24-hour television network in partnership with ESPN, dubbed the Longhorn Network. ESPN agreed to pay a $300 million guaranteed rights fee over 20 years to the university and to IMG College, the school’s multimedia rights partner. The network covers the university’s intercollegiate athletics, music, cultural arts, and academics programs. The channel first aired in September 2011.

     
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