An intelligent vertical trench DMOS on SIMOX-substrate

This paper describes 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: silicon on insulator). The vertical dielectric isolation between the Trench-DMOS and the control circuit is formed by the SIMOX-Process (SIMOX: separation by implanted oxygen) and the lateral isolation is realized by the LOGOS technology. The self-protection 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 15 V. This device can be used, for example, as an "intelligent" switch in a dimmer circuit for automotive application.