Degradation of short-channel MOSFET's under constant current stress across gate and drain

• Published in: IEEE transactions on electron devices Vol. 33; no. 9; pp. 1329 - 1333
• Main Authors: Bhattacharyya, A., Shabde, S.N.
• Format: Journal Article
• Language: English
• Published: New York, NY IEEE 01.09.1986; Institute of Electrical and Electronics Engineers
• Subjects: Applied sciences; Electronics; Exact sciences and technology; Semiconductor electronics. Microelectronics. Optoelectronics. Solid state devices; Transistors; Field effect transistor; MOS transistor
• ISSN: 0018-9383; 1557-9646
• DOI: 10.1109/T-ED.1986.22666

We have employed a technique of constant current stress between the gate and drain of a MOS transistor to study the degradation of the threshold voltage, transconductance, and substrate current characteristics of the transistor. From the transistor characteristics, we propose that the degradation mechanism is a combined effect of trapping of holes in the gate oxide created by impact ionization due to the high electric field (> 8 MV/cm) across the oxide, and electron trapping phenomena. The degradation characteristics of the transistor under this constant current stress are quite similar to that observed normally due to the injection of hot electrons in the gate oxide when the transistor is biased in "ON" condition and the gate and drain voltages are selected to produce maximum substrate current.