Smart power devices integrate a microcell power transistor and support circuits, for example control circuits or diagnostic circuits, in the same semiconductor die. The microcell power transistor controls a vertical current flow between a source electrode and a drain electrode placed at opposing sides of the semiconductor die. The support circuits are typically based on lateral low or high voltage transistors in CMOS (complementary metal-oxide-semiconductor) technology.
It is desirable to improve the reliability of semiconductor devices integrating power transistor cells and lateral transistors and to reduce manufacturing costs of such devices.