Abstract: A method of manufacturing a high-speed operable and broadband operable semiconductor device where a light-receiving element section, a CMOS element and a bipolar transistor element having a double polysilicon structure are formed on one chip. By performing the same conductivity type ion implantation, the same conductivity type diffusion layers (examples thereof include N-type diffusion layers, an anode diffusion layer, P-type well diffusion layer and collector diffusion layer as P-type diffusion layers, a cathode diffusion layer and collector contact diffusion layer as N-type diffusion layers, a source/drain diffusion layer and base Poly-Si diffusion layer as N-type diffusion layers, and a source/drain diffusion layer and base Poly-Si diffusion layer as P-type diffusion layers) are simultaneously formed in two or more regions among a light-receiving element region, CMOS element region and bipolar transistor element region of a semiconductor substrate or of an epitaxial layer over the semiconductor substrate.

Abstract: A method for producing a semiconductor device with a built-in light receiving element is provided. The device comprises a light receiving element region for receiving and converting an optical signal to an electric signal, the light receiving element region being provided on a substrate. The method comprises the steps forming an anti-reflection film in the light receiving element region on the substrate, and forming a protection film, the protection film serving as an etch stop film in a subsequent etching step.

Abstract: A first layer is formed on an underlying substrate having a surface layer made of semiconductor of a first conductivity type. The first layer is made of semiconductor having a resistance higher than that of the surface layer. A first impurity diffusion region of a second conductivity type is formed in a partial surface region of the first layer. The first impurity diffusion region does not reach the surface of the underlying substrate. A second impurity diffusion region of the first conductivity type is disposed in the first layer and spaced apart from the first impurity diffusion region. The second impurity diffusion region reaches the surface of the underlying substrate. A separation region is disposed between the first and second impurity diffusion regions. The separation region comprises a trench formed in the first layer and dielectric material disposed at least in a partial internal region of the trench.

Abstract: A first layer is formed on an underlying substrate having a surface layer made of semiconductor of a first conductivity type. The first layer is made of semiconductor having a resistance higher than that of the surface layer. A first impurity diffusion region of a second conductivity type is formed in a partial surface region of the first layer. The first impurity diffusion region does not reach the surface of the underlying substrate. A second impurity diffusion region of the first conductivity type is disposed in the first layer and spaced apart from the first impurity diffusion region. The second impurity diffusion region reaches the surface of the underlying substrate. A separation region is disposed between the first and second impurity diffusion regions. The separation region comprises a trench formed in the first layer and dielectric material disposed at least in a partial internal region of the trench.

Abstract: A method for producing a semiconductor device with a built-in light receiving element is provided. The device comprises a light receiving element region for receiving and converting an optical signal to an electric signal, the light receiving element region being provided on a substrate. The method comprises the steps forming an anti-reflection film in the light receiving element region on the substrate, and forming a protection film, the protection film serving as an etch stop film in a subsequent etching step.