Study of aluminum thermomigration as a low thermal budget technique for innovative power devices

摘要

The main feature of the thermomigration of Al/Si liquid droplets in silicon for the realization of isolation walls in bidirectional power devices is its low thermal budget. Therefore, it is compatible with the utilization of epitaxial substrates for innovative power devices, for example, with reduced on-state resistance. This paper describes the design and realization of a medium power SCR on epitaxy. After structure presentation and voltage blocking capability simulation, the specific issue of thermomigration on (111)-orientated epitaxial substrates is considered. Limitations to migration are found due to the off-axis cut necessary for good epitaxial growth. Electrical characterization exhibits great agreement with simulation, demonstrating the great potential of thermomigration as a low thermal budget technique for isolation walls processing for both standard structures and new devices on epitaxy.