Measurement of transient heating in a 1.1 mu m PMOSFET using thermal imaging

Measurements of transient heating in a 1.1- mu m PMOSFET, located in a 1.5- mu m*1.5-mm die and mounted on a gold-plated ceramic package are reported. Steady-state temperature profiles in a range of 500 mu m from midchannel are also presented . Temperatures were measured using the thermal imaging technique. The steady-state temperature in the device reached after 3 min of operation at mod V/sub gs/ mod = mod V/sub ds/ mod =5 V, was 322 K, and the rise time was 2 min. Theoretical results based on the analytical model of D. K. Sharma and K.V. Ramanathan (1983), in which a two-dimensional heat-diffusion equation is solved, are also presented. The theoretical calculations predict a 16-s rise time and a midchannel temperature of 371 K after 3 min of operation. The disagreement is most probably incurred by a simplified boundary condition used in the model. It seems that the model cannot sufficiently describe the actual heating in MOSFETs for VLSI.<
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