Abstract: A semiconductor device includes a semiconductor substrate, a body layer, a source region, a drift layer, a drain region, a gate insulating film, and a gate electrode. The semiconductor substrate has an active layer. An element region is included in the active layer and partitioned by a trench isolation portion. The body layer is disposed at a surface layer portion of the active layer. The source region is disposed at a surface layer portion of the body layer. The drift layer is disposed at the surface layer portion of the active layer. The drain region is disposed at a surface layer portion of the drift layer. The gate insulating film is disposed on a surface of the body layer. The gate electrode is disposed on the gate insulating film. One of the source region and the drain region being a high potential region is surrounded by the other one being a low potential region.

Abstract: On a substrate, a wiring layer is arranged by sequentially stacking a first insulation film, a lower electrode, a second insulation film, an intermediate electrode, a third insulation film, and an upper electrode in this order. A capacitor includes a first capacitor having the lower electrode and the intermediate electrode, and a second capacitor having the intermediate electrode and the upper electrode. The first capacitor and the second capacitor are connected in parallel to each other by electrically connecting the lower electrode and the upper electrode. Further, the intermediate electrode has a higher potential than the lower layer electrode and the upper electrode.

Abstract: A semiconductor device includes a semiconductor substrate, an upper diffusion region and a lower diffusion region. The semiconductor substrate has a main surface. The upper diffusion region of a first conductivity type is disposed close to the main surface of the semiconductor device. The lower diffusion region of a second conductivity type is disposed up to a position deeper than the upper diffusion region in a depth direction of the semiconductor substrate from the main surface as a reference, and has a higher impurity concentration than the semiconductor substrate. A diode device is provided by having a PN junction surface at an interface between the upper diffusion region and the lower diffusion region, and the PN junction surface has a curved surface disposed at a portion opposite to the main surface.

Abstract: A semiconductor device includes: a semiconductor substrate having a diode formation region; an upper diffusion region of a first conductivity type provided on a surface layer of a main surface of the semiconductor substrate in the diode formation region; and a lower diffusion region of a second conductivity type provided at a position deeper than the upper diffusion region with respect to the main surface in a depth direction of the semiconductor substrate, the lower diffusion region having a higher impurity concentration as compared to the semiconductor substrate. The lower diffusion region provides a PN joint surface with the upper diffusion region at a position deeper than the main surface, and has a maximum point indicating a maximum concentration in an impurity concentration profile of the lower diffusion region in the diode formation region.

Abstract: A semiconductor device includes a semiconductor substrate, a body layer, a source region, a drift layer, a drain region, a gate insulating film, and a gate electrode. The semiconductor substrate has an active layer. An element region is included in the active layer and partitioned by a trench isolation portion. The body layer is disposed at a surface layer portion of the active layer. The source region is disposed at a surface layer portion of the body layer. The drift layer is disposed at the surface layer portion of the active layer. The drain region is disposed at a surface layer portion of the drift layer. The gate insulating film is disposed on a surface of the body layer. The gate electrode is disposed on the gate insulating film. One of the source region and the drain region being a high potential region is surrounded by the other one being a low potential region.

Abstract: On a substrate, a wiring layer is arranged by sequentially stacking a first insulation film, a lower electrode, a second insulation film, an intermediate electrode, a third insulation film, and an upper electrode in this order. A capacitor includes a first capacitor having the lower electrode and the intermediate electrode, and a second capacitor having the intermediate electrode and the upper electrode. The first capacitor and the second capacitor are connected in parallel to each other by electrically connecting the lower electrode and the upper electrode. Further, the intermediate electrode has a higher potential than the lower layer electrode and the upper electrode.

Abstract: A semiconductor device includes a semiconductor substrate, an upper diffusion region and a lower diffusion region. The semiconductor substrate has a main surface. The upper diffusion region of a first conductivity type is disposed close to the main surface of the semiconductor device. The lower diffusion region of a second conductivity type is disposed up to a position deeper than the upper diffusion region in a depth direction of the semiconductor substrate from the main surface as a reference, and has a higher impurity concentration than the semiconductor substrate. A diode device is provided by having a PN junction surface at an interface between the upper diffusion region and the lower diffusion region, and the PN junction surface has a curved surface disposed at a portion opposite to the main surface.

Abstract: A buried n-type region is provided in a surface layer portion of an n-type body layer of a Pch MOSFET. This makes it possible to lower the threshold voltage Vt. In a portion of the n-type body layer other than the buried n-type region, since an n-type impurity concentration can be kept relatively high, the threshold voltage Vt can be lowered while securing an on-breakdown voltage. Furthermore, since an accumulation region is configured by an n-type active layer, a partial high concentration portion is not formed in a p-type drift layer. Therefore, as in the case where the partial high concentration portion is generated in the p-type drift layer, a reduction in a breakdown voltage caused by an electric field concentration can be restricted from occurring with a distribution in which equipotential lines are concentrated.

Abstract: A buried n-type region is provided in a surface layer portion of an n-type body layer of a Pch MOSFET. This makes it possible to lower the threshold voltage Vt. In a portion of the n-type body layer other than the buried n-type region, since an n-type impurity concentration can be kept relatively high, the threshold voltage Vt can be lowered while securing an on-breakdown voltage. Furthermore, since an accumulation region is configured by an n-type active layer, a partial high concentration portion is not formed in a p-type drift layer. Therefore, as in the case where the partial high concentration portion is generated in the p-type drift layer, a reduction in a breakdown voltage caused by an electric field concentration can be restricted from occurring with a distribution in which equipotential lines are concentrated.

Abstract: A semiconductor device includes: a semiconductor substrate having a diode formation region; an upper diffusion region of a first conductivity type provided on a surface layer of a main surface of the semiconductor substrate in the diode formation region; and a lower diffusion region of a second conductivity type provided at a position deeper than the upper diffusion region with respect to the main surface in a depth direction of the semiconductor substrate, the lower diffusion region having a higher impurity concentration as compared to the semiconductor substrate. The lower diffusion region provides a PN joint surface with the upper diffusion region at a position deeper than the main surface, and has a maximum point indicating a maximum concentration in an impurity concentration profile of the lower diffusion region in the diode formation region.