Ghavam Shahidi

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Ghavam G. Shahidi is an Iranian-American electrical engineer and IBM Fellow. He is the director of Silicon Technology at the IBM Thomas J Watson Research Center. He is best known for his pioneering work in silicon-on-insulator (SOI) complementary metal–oxide–semiconductor (CMOS) technology since the late 1980s.


He studied electrical engineering at MIT, where he wrote a PhD thesis on "velocity overshoot in deeply scaled MOSFETs" (metal-oxide-semiconductor field-effect transistors), under supervision of Professor Dimitri A. Antoniadis.

A 60 nanometer silicon MOSFET (metal-oxide-semiconductor field-effect transistor) was fabricated by Shahidi with Antoniadis and Henry I. Smith at MIT in 1986. [1] [2] The device was fabricated using X-ray lithography. [3]

Shahidi joined IBM Research in 1989, where he initiated and subsequently led the development of silicon-on-insulator (SOI) complementary metal–oxide–semiconductor (CMOS) technology at IBM. [4] It was called the SOI Research Program, which he led at the IBM Thomas J Watson Research Center. [4] Since then, he was the chief architect of SOI technology at IBM, leading the development of high-performance CMOS and SOI technologies at IBM Microelectronics. He made fundamental contributions to SOI technology, from materials research to the development of the first commercially viable devices. He was supported by his boss Bijan Davari, who believed in the technology and supported Shahidi's team. [5]

He was a key figure in making SOI CMOS technology a manufacturable reality and enabling the continued miniaturization of microelectronics. [6] Early SOI technology had a number of problems with manufacturing, modeling, circuits, and reliability, and it was not clear that it could offer performance gains over established technologies. [5] In the early 1990s, he demonstrated a novel technique of combining silicon epitaxial overgrowth and chemical mechanical polishing to prepare device-quality SOI material for fabricating devices and simple circuits, which led to IBM expanding its research program to include SOI substrates. He was also the first to demonstrate the power-delay advantage of SOI CMOS technology over traditional bulk CMOS in microprocessor applications. He overcame barriers preventing the semiconductor industry's adoption of SOI, and was instrumental in driving SOI substrate development to the quality and cost levels suitable for mass-production. [6]

This led to the first commercial use of SOI in mainstream CMOS technology. [4] SOI was first commercialized in 1995, when Shahidi's work on SOI convinced John Kelly, who ran IBM's server division, to adopt SOI in the AS/400 line of server products, which used 220 nm CMOS with copper metallization SOI devices. In early 2001, he used SOI to developed a low-power RF CMOS device, resulting in increased radio frequency. Later that year, IBM was set to introduce 130 nanometer CMOS SOI devices with copper and low-κ dielectric for the back end, based on Shahidi's work. [5]

His work resulted in the qualification of multiple CMOS SOI technologies and their transfer to manufacturing; establishment of design infrastructure; and the first mainstream use of SOI. He remained with IBM Microelectronics as the director of high-performance logic development until 2003. He then moved back to IBM's Watson's Laboratory as the Director of Silicon Technology. [7]

As director of silicon technology at IBM Research, he was researching lithography technology in the early 2000s. In 2004, he announced plans for IBM to commercialize lithography based on light filtered through water, and then X-ray lithography within the next several years. He also announced that his team were investigating 20 new semiconductor materials. [7]

Shahidi received the Institute of Electrical and Electronics Engineers' J J Ebers Award in 2006, for his "contributions and leadership in the development of Silicon-On-Insulator CMOS technology". [8] He is currently the director of Silicon Technology at the IBM Thomas J Watson Research Center in Yorktown Heights, New York. [6]

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Thin-film transistor field-effect transistor device

A thin-film transistor (TFT) is a special type of metal–oxide–semiconductor field-effect transistor (MOSFET) made by depositing thin films of an active semiconductor layer as well as the dielectric layer and metallic contacts over a supporting substrate. A common substrate is glass, because the primary application of TFTs is in liquid-crystal displays (LCDs). This differs from the conventional bulk MOSFET transistor, where the semiconductor material typically is the substrate, such as a silicon wafer.

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Dawon Kahng South Korean engineer

Dawon Kahng was a Korean-American electrical engineer and inventor, known for his work in solid-state electronics. He is best known for inventing the MOSFET, also known as the MOS transistor, with Mohamed Atalla in 1959. Atalla and Kahng developed both the PMOS and NMOS processes for MOSFET semiconductor device fabrication. The MOSFET is the most widely used type of transistor, and the basic element in most modern electronic equipment.

Mohamed M. Atalla mechanical engineer

Mohamed Mohamed Atalla was an Egyptian–American engineer, physical chemist, cryptographer, inventor and entrepreneur. His pioneering work in semiconductor technology laid the foundations for modern electronics. Most importantly, his invention of the MOSFET in 1959, along with his earlier surface passivation and thermal oxidation processes, revolutionized the electronics industry. He is also known as the founder of the data security company Atalla Corporation, founded in 1972, which introduced the first hardware security module and was a pioneer in online security. He received the Stuart Ballantine Medal and was inducted into the National Inventors Hall of Fame for his important contributions to semiconductor technology as well as data security.

Bijan Davari is an Iranian-American engineer. He is an IBM Fellow and Vice President at IBM Thomas J Watson Research Center, Yorktown Hts, NY. His pioneering work in the miniaturization of semiconductor devices changed the world of computing. His research led to the first generation of voltage-scaled deep-submicron CMOS with sufficient performance to totally replace bipolar technology in IBM mainframes and enable new high-performance UNIX servers. He is credited with leading IBM into the use of copper and silicon on insulator before its rivals. He is a member of the U.S. National Academy of Engineers and is known for his seminal contributions to the field of CMOS technology. He is an IEEE Fellow, recipient of the J J Ebers Award in 2005 and IEEE Andrew S. Grove Award in 2010. At the present time, he leads the Next Generation Systems Area of research.

Gary Patton

Dr. Gary Patton is an American technologist and business executive. He is currently the Corporate Vice President and General Manager of Design Enablement in the Technology Development Group at Intel. He has spent most of his career in IBM, starting in IBM's Research Division and holding management and executive positions in IBM's Microelectronics Division in Technology Development, Design Enablement, Manufacturing, and Business Line Management.


  1. Shahidi, Ghavam G.; Antoniadis, Dimitri A.; Smith, Henry I. (December 1986). "Electron velocity overshoot at 300 K and 77 K in silicon MOSFETs with submicron channel lengths". 1986 International Electron Devices Meeting: 824–825. doi:10.1109/IEDM.1986.191325.
  2. Chou, Stephen Y.; Smith, Henry I.; Antoniadis, Dimitri A. (1986). "Sub‐100‐nm channel‐length transistors fabricated using x‐ray lithography". Journal of Vacuum Science & Technology B: Microelectronics Processing and Phenomena. 4 (1): 253–255. Bibcode:1986JVSTB...4..253C. doi:10.1116/1.583451. ISSN   0734-211X.
  3. Shahidi, Ghavam G.; Antoniadis, Dimitri A.; Smith, Henry I. (December 1988). "Reduction of hot-electron-generated substrate current in sub-100-nm channel length Si MOSFET's". IEEE Transactions on Electron Devices . 35 (12): 2430–. Bibcode:1988ITED...35.2430S. doi:10.1109/16.8835.
  4. 1 2 3 "Ghavam G. Shahidi". IEEE Xplore . Institute of Electrical and Electronics Engineers . Retrieved 16 September 2019.
  5. 1 2 3 "SOI scientist counted among latest IBM fellows". EE Times . 30 May 2001.
  6. 1 2 3 "Ghavam Shahidi". Engineering and Technology History. Institute of Electrical and Electronics Engineers . Retrieved 16 September 2019.
  7. 1 2 "A Whole New World of Chips". Business Week . Archived from the original on 2011-02-21.
  8. "Past J.J. Ebers Award Winners". IEEE Electron Devices Society . Institute of Electrical and Electronics Engineers . Retrieved 16 September 2019.