An intelligent vertical trench DMOS on SIMOX-substrate

This paper desribes first results of a monolithically integrated smart power device which uses a vertical Trench-DMOS as a power switch and a signal and control circuit fabricated in a SOI-CMOS technology (SOI: siliconon insulator). The vertical dielectric isolation between the Trench-DMOS and the control circuit is formed by the SIMOX (SIMOX: seperation by implanted oxygen) and the lateral isolation is realized by the LOCOS technology. The selfprotection of the entire device is achieved by measuring the temperature and the load current of the power transistor. The protection is provided by analog and digital CMOS circuits with a supply voltage of 15V. This device can be used e.g. as an "intelligent" switch in a dimmer circuit for automotive application.