Patent ID: 7772646

Claim:
A method of manufacturing a semiconductor device with a semiconductor body, the method comprising: forming a semiconductor substrate and a semiconductor region, which are separated from each other by an electrically insulating layer, said electrically insulating layer including a first and a second sub-layer which are adjacent when viewed in projection, wherein the first sub-layer has a smaller thickness than the second sub-layer; forming at least one digital semiconductor element in a first sub-region of the semiconductor region situated above the first sub-layer; and forming at least one analog semiconductor element in a second sub-region of the semiconductor region situated above the second sub-layer, characterized in that the second sub-layer is formed in such a manner that the lower border thereof is recessed in the semiconductor body in relation to the lower border of the first sub-layer; wherein the thickness of the semiconductor region at the location of the first and the second sub-layer is such that the digital and analog semiconductor elements operate in a fully depleted mode.