METHOD OF FORMING A VERTICAL POWER SEMICONDUCTOR DEVICE AND STRUCTURE THEREFOR

摘要

A method of forming medium breakdown voltage vertical transistors (11) and lateral transistors (12, 13) on the same substrate (14) provides for optimizing the epitaxial layer (16) for the lateral transistors (12, 13). The vertical transistor (11) is formed in a well (18) that has a lower resistivity than the epitaxial layer (16) to provide the required low on-resistance for the vertical power transistor (11).