Patent ID: 8975151
Filing Date: 2015-03-10
Classification: H01L

Abstract:
1. A method for forming a buried material layer in a semiconductor body, the method comprising: providing a semiconductor body having a first side, and having a plurality of first trenches extending from the first surface into the semiconductor body, each of the plurality of first trenches having a bottom and having at least one sidewall, and the plurality of first trenches being separated from one another by semiconductor mesa regions; forming a first material layer on the bottom of each of the plurality of first trenches such that the first material layer leaves at least one segment of at least one sidewall of each of the plurality of trenches uncovered; filling each of the plurality of first trenches by epitaxially growing a semiconductor material from the at least one uncovered sidewall segment; after filling the first trenches: a) forming second trenches in the mesa regions at least once, the second trenches extending from the first surface in a vertical direction into the semiconductor body, the second trenches each having a bottom and having at least one sidewall; b) forming second material layers on the bottom of the second trenches, second material layers leaving at least one segment of at least one sidewall of each of the second trenches uncovered; and c) filling the second trenches by epitaxially growing a semiconductor material on at least one uncovered sidewall segment of each second trench.