Normally-Off Thin-Film Silicon Heterojunction Field-Effect Transistors and Application to Complementary Circuits

• Published in: IEEE electron device letters Vol. 35; no. 5; pp. 545 - 547
• Main Author: Hekmatshoar, Bahman
• Format: Journal Article
• Language: English
• Published: New York, NY IEEE 01-05-2014; Institute of Electrical and Electronics Engineers; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Applied sciences; Chemical vapor deposition (including plasma-enhanced cvd, mocvd, etc.); Compound structure devices; Cross-disciplinary physics: materials science; rheology; Electronics; Exact sciences and technology; Heterojunctions; Logic gates; Materials science; Methods of deposition of films and coatings; film growth and epitaxy; Microelectronic fabrication (materials and surfaces technology); MOSFET; Physics; plasma CVD; Reliability; Semiconductor electronics. Microelectronics. Optoelectronics. Solid state devices; Silicon; Substrates; Thin-film transistors; Transistors; silicon; Thin-film transistors; heterojunctions; plasma CVD; Gate current; MOS technology; MOSFET; Transistor gate; Multiple layer; Thin film; Crystalline material; Microelectronic fabrication; Silicon; Thin film transistor; Heterojunction field effect transistor; PECVD; On off effect; Heterojunction
• ISSN: 0741-3106; 1558-0563
• DOI: 10.1109/LED.2014.2309113

A thin blocking structure is incorporated in the gate-stack of heterojunction field-effect transistor (HJFET) devices to substantially suppress the gate current when the gate heterojunction is forward-biased. As a result, normally-OFF HJFET devices with MOSFET-like characteristics are obtained. The HJFET devices are comprised of gate, source, and drain regions formed by plasma-enhanced chemical vapor deposition on thin-film crystalline Si substrates at temperatures below 200°C. The ON/OFF ratios larger than 106, operation voltages as low as 1 V, and subthreshold slopes of ~85 mV/decade are demonstrated. The HJFET devices can be integrated with MOSFET devices fabricated on the same crystalline Si substrates to form complementary circuits.