Modelling of self-heating effect in thin SOI and Partial SOI LDMOS power devices

This paper presents a comprehensive 2-D and I-D study of the self-heating e ffect in thin Silicon-on-Insulator (SOI) and Partial SOI LDMOS power device s. A simple 1-D self-heating model based on a PSPICE RC thermal circuit whi ch accounts for the temperature rise in on-state, transient and short-circu it conditions is developed. Unlike previous I-D modelling attempts for SOI devices, our model takes into account the feedback effect of the local devi ce temperature on the thermal conductivity and specific heat through an equ ivalent electrical RC network consisting of voltage controlled resistors an d capacitors. The 1-D model is thoroughly assessed against extensive 2-D th ermal simulations performed using the SILVACO-ATLAS device simulator and th e results indicate an excellent agreement in all operating conditions. Furt hermore, an accurate comparison between the thin SOI and Partial SOI device s is carried out. (C) 1999 Elsevier Science Ltd. All rights reserved.