Method of manufacturing bicmos device

Abstract

A semiconductor device and a method for manufacturing such a device are presented. The type of semiconductor device is one which merges one type of transistor (e.g., bipolar junction transistors) with another type (e.g., CMOS transistors). Specifically, the semiconductor device may comprise a semiconductor substrate and first buried layers of a first conductive and second type buried layers of a second conductive type both formed within the semiconductor substrate. The first buried layers are preferably at a different level within the semiconductor substrate then the level of the second buried layers. First epitaxial layer portions are formed over the first buried layers and second epitaxial layer portions are formed over the second type buried layers. Isolation regions are formed on the first epitaxial layer portions. In forming the semiconductor substrate, photoresists are formed at regular spatial intervals on a substrate. Exposed portions of the substrate are then etched to form etched portions of the substrate, and ions of a second conductive type are implanted into the etched portions of the substrate. The photoresists are then removed, and ions of a first conductive type are then implanted into the substrate. Accordingly, the first and second type buried layers are formed within the substrate, the first buried layers being positioned at a first level and the second buried layers being positioned at a second level lower than the first level.