A numerical model of avalanche breakdown in MOSFET's
Abstract
A numerical model for avalanche breakdown in MOSFETs is developed, which can be applied not only to the normal breakdown in p-MOSFETs or long-channel n-MOSFETs, but also to the negative-resistance breakdown in short-channel n-MOSFETs. The electric-field distribution is accurately obtained by a two-dimensional numerical analysis. The ionization integral and multiplication factor for a high-field path are obtained from the field distribution and utilized for quantitative prediction of the breakdown voltages. Negative-resistance breakdown observed in short-channel n-MOSFETs is simulated by including the positive feedback effect of impact ionization-induced substrate current in the two-dimensional model of the intrinsic FET. It is shown that the breakdown voltage and sustain voltage can be obtained within an accuracy of 2 V. The model is expected to be useful for designing MOSFETs with higher breakdown voltages.
- Publication:
-
IEEE Transactions on Electron Devices
- Pub Date:
- July 1978
- DOI:
- 10.1109/T-ED.1978.19179
- Bibcode:
- 1978ITED...25..825T
- Keywords:
-
- Avalanches;
- Electrical Faults;
- Field Effect Transistors;
- Channel Capacity;
- Channels (Data Transmission);
- Computer Techniques;
- Electron Density Profiles;
- Metal Oxide Semiconductors;
- Negative Resistance Devices;
- Two Dimensional Models;
- Volt-Ampere Characteristics;
- Electronics and Electrical Engineering