Heat flow analysis for EOS/ESD protection device design in SOI technology

Power-to-failure versus time-to-failure profiles for SOI protection devices are generated through a consideration of Joule heating. Experimental results are presented to justify assumptions made in the investigation of heat flow in SOI devices. A lossy transmission line equivalent model has been used to model the heat diffusion problem. A design space for multifinger NMOS protection devices has been developed on the basis of self-heating constraints. The method of images has been used to transform the multifinger device to an equivalent single-finger device to simplify the heat flow analysis.