One aspect includes a method for forming a buried material layer in a semiconductor body, including 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 has a bottom and has at least one sidewall and the plurality of first trenches is separated from one another by semiconductor mesa regions. A first material layer is formed 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. Each of the plurality of first trenches is filled by epitaxially growing a semiconductor material from the at least one uncovered sidewall segment. After filling the first trenches, second trenches are formed in the mesa regions.