Abstract: This invention is directed to a manufacturing method of a semiconductor device having a MOS transistor and a diffusion resistance layer formed on a same semiconductor substrate, where current leakage from the diffusion resistance layer is minimized. The manufacturing method of the semiconductor device of the invention has following features. That is, a CVD insulation film is formed on a whole surface of an n-type well including on a gate electrode and a p+-type diffusion resistance layer formed thereon. Then, a second photoresist layer is formed having an opening above a part of the diffusion resistance layer. By using this second photoresist layer as a mask, an anisotropic etching is performed to the CVD insulation film to form a sidewall spacer on a sidewall of the gate electrode.

Abstract: In a semiconductor device having a MOS transistor and a diffused resistor layer, a leakage current of a diffused resistor layer is suppressed. A film of gate electrode material is formed over the entire surface of an N-type well, a photoresist layer is formed to mask a region to form a gate electrode and portions of the diffused resistor layer and the gate electrode and a damage prevention films are formed by anisotropically etching the film of gate electrode material. After forming a CVD insulation film over the entire surface of the N-type well, sidewall spacers are formed on sidewalls of the gate electrode and the damage prevention films by anisotropically etching the CVD insulation film. A source layer and a drain layer of the MOS transistor and contact regions to the diff-used resistor layer are formed by doping portions of the N-type well and the diffused resistor layer with high concentration P-type impurities using the gate electrode, the damage prevention film and the sidewall spacers as a mask.

Abstract: In a semiconductor device having a MOS transistor and a diffused resistor layer, a leakage current of a diffused resistor layer is suppressed. A film of gate electrode material is formed over the entire surface of an N-type well, a photoresist layer is formed to mask a region to form a gate electrode and portions of the diffused resistor layer and the gate electrode and a damage prevention films are formed by anisotropically etching the film of gate electrode material. After forming a CVD insulation film over the entire surface of the N-type well, sidewall spacers are formed on sidewalls of the gate electrode and the damage prevention films by anisotropically etching the CVD insulation film. A source layer and a drain layer of the MOS transistor and contact regions to the diff-used resistor layer are formed by doping portions of the N-type well and the diffused resistor layer with high concentration P-type impurities using the gate electrode, the damage prevention film and the sidewall spacers as a mask.

Abstract: This invention is directed to a manufacturing method of a semiconductor device having a MOS transistor and a diffusion resistance layer formed on a same semiconductor substrate, where current leakage from the diffusion resistance layer is minimized. The manufacturing method of the semiconductor device of the invention has following features. That is, a CVD insulation film is formed on a whole surface of an n-type well including on a gate electrode and a p+-type diffusion resistance layer formed thereon. Then, a second photoresist layer is formed having an opening above a part of the diffusion resistance layer. By using this second photoresist layer as a mask, an anisotropic etching is performed to the CVD insulation film to form a sidewall spacer on a sidewall of the gate electrode.