Patent ID: 9284186
Filing Date: 2016-03-15
CPC Classification: B81C

Claim Text:
1. A method of manufacturing a semiconductor device having a surface of a semiconductor substrate on which plural semiconductor elements are formed, the method comprising: forming an insulating film layer (Buried Oxide (BOX) layer) on a surface of a semiconductor substrate; forming an SOI (Silicon on Insulator) layer on a surface of the insulating film layer (BOX layer); removing a part of the SOI layer to form a movable portion of an electromechanical element; forming a TEOS (Tetra Ethyl Ortho Silicate) oxide film on a surface of the SOI layer and the insulating film layer (BOX layer) that is exposed through etching of the SOI layer; forming an inorganic thin film on a surface of the TEOS oxide film, the inorganic thin film including a first Poly-Si (Poly-Silicon) film; forming a resist mask on the first Poly-Si film; forming etching holes by removing a part of the first Poly-Si film using the resist mask as an etching mask; removing a part of the insulating film layer (BOX layer) and the TEOS oxide film through a gas-phase HF (Hydrogen Fluoride) treatment to the semiconductor substrate so as to form a hollow portion in which the movable portion of the electromechanical element is arranged and is separated from the semiconductor substrate, the TEOS oxide film, and the inorganic thin film; and sealing the semiconductor device by forming a second Poly-Si (Poly-Silicon) film or an SiC (Silicon Carbide) film on the first Poly-Si film having the etching holes, wherein the etching holes of the first Poly-Si film are present after the formation of the second Poly-Si film or the SiC film.