Title :
The impact of non-equilibrium transport on breakdown and transit time in bipolar transistors
Author :
Crabbe, E.F. ; Stork, J.M.C. ; Baccarani, G. ; Fischetti, M.V. ; Laux, S.E.
Author_Institution :
IBM Thomas J. Watson Res. Center, Yorktown Heights, NY, USA
Abstract :
Impact ionization and velocity overshoot in the base-collector junction of bipolar transistors are studied using Monte Carlo simulation and the hydrodynamic energy-balance equation. For advanced bipolar transistors, the carrier energy lags the electric field; therefore, the maximum impact ionization rate occurs deep into the junction. A simplified solution of the energy-balance equation can accurately model this nonlocal behavior. Excellent agreement with measurements of the multiplication factor for a variety of base-collector profiles is obtained. As a consequence of this nonequilibrium effect, velocity overshoot is expected and its trade-off with breakdown is analyzed in detail.<>
Keywords :
Monte Carlo methods; bipolar transistors; digital simulation; electric breakdown of solids; impact ionisation; semiconductor device models; Monte Carlo simulation; base-collector junction; bipolar transistors; breakdown; carrier energy; electric field; energy model; hydrodynamic energy-balance equation; impact ionization; multiplication factor; nonequilibrium transport; transit time; velocity overshoot; Bipolar transistors; Electric breakdown; Equations; Hydrodynamics; Impact ionization;
Conference_Titel :
Electron Devices Meeting, 1990. IEDM '90. Technical Digest., International
Conference_Location :
San Francisco, CA, USA
DOI :
10.1109/IEDM.1990.237067
