There is a method of manufacturing a semiconductor device with a semiconductor body comprising a semiconductor substrate and a semiconductor region which are separated from each other with an electrically insulating layer which includes a first and a second sub-layer which, viewed in projection, are adjacent to one another, wherein the first sub-layer has a smaller thickness than the second sub-layer, and wherein, in a first sub-region of the semiconductor region lying above the first sub-layer, at least one digital semiconductor element is formed and, in a second sub-region of the semiconductor region lying above the second sub-layer, at least one analog semiconductor element is formed.According to an example embodiment, the second sub-layer is formed in that the lower border thereof is recessed in the semiconductor body in relation to the lower border of the first sub-layer Fully depleted SOI devices are thus formed.