Title :
Temperature and channel-length dependence of impact ionization in p-channel MOSFETs
Author :
Mastrapasqua, M. ; Bude, J. ; Pinto, M. ; Manchanda, L. ; Lee, K.F.
Author_Institution :
AT&T Bell Labs., Murray Hill, NJ, USA
Abstract :
The impact ionization (II) current of p-channel MOSFETs designed for 0.1 /spl mu/m operation has been investigated as a function of temperature and channel length, L/sub ch/ down to 0.1 /spl mu/m. It has been experimentally observed that at any channel length, the substrate current to source current ratio, I/sub R/, decreases with decreasing lattice temperature. The temperature behavior of the II multiplication measured here is opposite to that in bulk. Such a temperature dependence of I/sub R/, has been already observed for n-MOSFETs but, to our knowledge, has never been reported in p-MOSFETs. Also, the minimum drain bias for which II is observed is V/sub DS/=1.3 V for the 0.1 /spl mu/m p-MOSFET devices, which is substantially higher than that observed in deep sub-micron n-MOSFETs. Furthermore, I/sub R/ is found to increase with decreasing L/sub ch/. Insight into the physical mechanisms behind these phenomena is given through full band Monte Carlo simulations.<>
Keywords :
Monte Carlo methods; digital simulation; impact ionisation; insulated gate field effect transistors; semiconductor device models; 0.1 micron; 1.3 V; channel-length dependence; deep submicron PMOSFET; full band Monte Carlo simulations; impact ionisation multiplication; impact ionization current; lattice temperature; minimum drain bias; p-channel MOSFETs; temperature dependence; Charge carrier processes; Doping profiles; Heating; Impact ionization; Lattices; Length measurement; MOSFET circuits; Performance evaluation; Solid modeling; Temperature dependence;
Conference_Titel :
VLSI Technology, 1994. Digest of Technical Papers. 1994 Symposium on
Conference_Location :
Honolulu, HI, USA
Print_ISBN :
0-7803-1921-4
DOI :
10.1109/VLSIT.1994.324425
