A method for producing an insulating layer of varying thickness and a semiconductor device with an insulating layer of varying thickness

A layer (520 ') with a laterally varying thickness, a substrate (510) having a first surface (511) and one on the first surface (511) of the substrate (510) formed on insulation layer (520) is provided. A plurality of at least one of recesses and openings (525) is formed on the insulating layer (520), wherein the plurality is arranged in a distance measure (p). Each of the at least one of recesses and openings (525) has a lateral width (w), wherein at least one of the distance measure (p) and the lateral width (W) varies in the lateral direction. The plurality of at least one of recesses and openings (525) defines a particular area in the insulating layer (520). The insulating layer (520) having the plurality of at least one of recesses and openings (525) is annealed at elevated temperatures, so that the insulating layer (520) at least partially melts, the insulating layer (520) in the given area with a laterally provide varying width.