Test structure configurations for analysis of field effect influenced self-heating and thermal coupling in High Voltage SiGe HBTs

This paper presents several test structure configurations that facilitate a comprehensive assessment of self-heating and thermal coupling effects in High Voltage SiGe HBTs in a DTI on SOI process. Several layout test structures are investigated including variations in device separations, multi-device arrays and the influence of the substrate contact in the regions outside the trench isolation, and indeed the potential for trench field effects themselves, the latter two both due to the high voltages involved. The findings are reported with a view to focus on a Compact Modelling solution implementable in a commercial CAD tool.