Semiconductor device in which bump used for fixing potential of silicon substrate can be easily formed

摘要

A semiconductor flip chip device having an SOI substrate in which a bump for fixing a potential of a silicon substrate is simply formed a layer (2), including a BOX layer and a silicon layer of the SOI substrate is formed. A semiconductor element selectively is formed on the silicon layer and an interlayer insulation film is then formed on the semiconductor element and the silicon layer. Selectively formed in a silicon nitride film (4) and the layer (2) is a hollow (41) extending from an upper surface of the silicon nitride film (4) to reach an upper surface of the silicon substrate (1). The hollow (41) is formed in an area where the semiconductor element is not formed. The hollow has its side surface defined by the silicon nitride film (4) and the layer (2) and its bottom surface defined by the upper surface of the silicon substrate (1). A bump (5d) made of solder is formed on a part of the upper surface of the silicon substrate (1) defining the bottom surface of the hollow (41). The bump (5d) is provided for fixing the potential of the silicon substrate (1).