A display device and method of fabricating the same are provided. The display device includes a substrate and a thin-film transistor formed on the substrate. The thin-film transistor includes a lower gate conductive layer disposed on the substrate, and a lower gate insulating film disposed on the lower gate conductive layer The lower gate insulating film includes an upper surface and sidewalls. The thin-film transistor includes an active layer disposed on the upper surface of the lower gate insulating film, the active layer including sidewalls. At least one of the sidewalls of the lower gate insulating film and at least one of the sidewalls of the active layer are aligned with each other.

An integrated circuit has a P-type substrate and an N-type LDMOS transistor. The LDMOS transistor includes a boron-doped diffused well (DWELL-B) and an arsenic-doped diffused well (DWELL-As) located within the DWELL-B. A first polysilicon gate having first sidewall spacers and a second polysilicon gate having second sidewall spacers are located over opposite edges of the DWELL-B. A source/IBG region includes a first source region adjacent the first polysilicon gate, a second source region adjacent the second polysilicon gate, and an integrated back-gate (IBG) region located between the first and second source regions. The first source region and the second source region each include a lighter-doped source sub-region, the IBG region including an IBG sub-region having P-type dopants, and the source/IBG region includes a heavier-doped source sub-region.

A method for manufacturing a semiconductor device according to an embodiment includes preparing a semiconductor layer including a first main surface and a second main surface and including a first semiconductor region of a first conductivity type, a second semiconductor region of a second conductivity type, a control electrode provided so as to face the second semiconductor region, and a third semiconductor region of the first conductivity type, ion-implanting an impurity of the second conductivity type into the first main surface to form a fourth semiconductor region in which an impurity concentration of the second conductivity type is a first concentration, and ion-implanting an impurity of the first conductivity type into the first main surface in an outer peripheral region of the semiconductor layer to form a fifth semiconductor region in which a net impurity concentration of the second conductivity type is a second concentration lower than the first concentration.

There is provided a diode including an anode electrode provided on a side of a front surface of a semiconductor substrate, an interlayer dielectric film disposed between the semiconductor substrate and the anode electrode, a first anode region of a first conductivity type provided on the front surface of the semiconductor substrate, a second anode region of a second conductivity type, which is different from the first conductivity type, provided on the front surface of the semiconductor substrate, a first contact hole provided in the interlayer dielectric film, causing the anode electrode to be in Schottky contact with the first anode region, and a second contact hole provided in the interlayer dielectric film and different from the first contact hole, causing the anode electrode to be in ohmic contact with the second anode region.

A semiconductor device includes a semiconductor substrate, a base region, an emitter region, a collector region, and an element isolation insulating film. The semiconductor substrate has a main surface. The base region has a first conductivity type and is disposed in a surface layer of the semiconductor substrate that is close to the main surface. The emitter region has a second conductivity type and is disposed in a surface layer of the base region. The collector region has the second conductivity type and is disposed at a portion in the surface layer of the semiconductor substrate apart from the emitter region. The element isolation insulating film is disposed on the main surface, and has a thermal oxide film being in contact with a junction interface between the base region and the emitter region.