A semiconductor device includes a first electrode, a second electrode, a first semiconductor region of a first conductivity type that is between the first electrode and the second electrode. A second semiconductor region is adjacent to the first semiconductor region along a first direction and includes a second conductivity type material. A first insulating region is provided within the second semiconductor region. A third electrode is provided on the first semiconductor region via a second insulating region.

Provided is a method for manufacturing a semiconductor device that improves the reliability of the semiconductor device. An opening is formed in an insulating film formed over a semiconductor substrate. At that time, a mask layer for formation of the opening is formed over the insulating film. The insulating film is dry etched and then wet etched. The dry etching step is finished before the semiconductor substrate is exposed at the bottom of the opening, and the wet etching step is finished after the semiconductor substrate is exposed at the bottom of the opening.

According to an embodiment, a semiconductor device is provided. The device includes a second region having a greater curvature than a first region. The device includes an epitaxy layer of a first conductivity type, a well of a second conductivity type in the epitaxy layer, a drain in the epitaxy layer, a source in the well, and a bulk in the well and in contact with the source, the bulk having a greater area in the second region than in the first region.

Electrical characteristics of a semiconductor device including the oxide semiconductor are improved. Furthermore, a highly reliable transistor with small variation in electrical characteristics is manufactured. An oxynitride insulating film functioning as a base insulating film and a transistor in contact with the oxynitride insulating film are provided. The transistor includes an oxide semiconductor film in contact with the oxynitride insulating film functioning as a base insulating film. The total amount of gas having a mass-to-charge ratio of 30 released from the oxynitride insulating film by heat treatment and double of the amount of a gas having a mass-to-charge ratio of 32 released from the oxynitride insulating film by heat treatment is greater than or equal to 510.sup.15/cm.sup.2 and less than or equal to 510.sup.16/cm.sup.2, or greater than or equal to 510.sup.15/cm.sup.2 and less than or equal to 310.sup.16/cm.sup.2.

A first silicon controlled rectifier has a breakdown voltage in a first direction and a breakdown voltage in a second direction. A second silicon controlled rectifier has a breakdown voltage with a higher magnitude than the first silicon controlled rectifier in the first direction, and a breakdown voltage with a lower magnitude than the first silicon controlled rectifier in the second direction. A bidirectional electrostatic discharge (ESD) structure utilizes both the first silicon controlled rectifier and the second silicon controlled rectifier to provide bidirectional protection.

A method for fabricating a high-voltage transistor on a semiconductor substrate includes defining and forming shallow trench isolation regions for all of the transistors, defining and forming well regions for all of the transistors, forming a gate oxide layer in the well regions for all of the transistor, forming gates for all of the transistors over the gate oxide layer, implanting a dopant to form lightly-doped drain regions for all of the transistors, the lightly-doped drain regions for at least drains of the high-voltage transistors being spaced apart from an inner edge of the shallow trench isolation regions, forming gate spacers at sides of the gates of all of the transistors, and implanting a dopant to form sources and drains for all of the transistors, the drains of the high-voltage transistors being formed completely surrounded by the lightly-doped drain regions of the high-voltage transistors.

A semiconductor device with reduced power consumption. The device includes: an n-type well region overlying the main surface of a semiconductor substrate; an element isolation region overlying the main surface; a first and a second active region located in the n-type well region and surrounded by the element isolation region; an insulating film overlying the main surface in the first active region; a semiconductor layer overlying the insulating film; a gate electrode layer overlying the semiconductor layer through a gate insulating film; a p-type source and a drain region formed in the semiconductor layer at both ends of the gate electrode layer; a dummy gate electrode layer overlying the semiconductor layer through the gate insulating film; an n-type semiconductor region overlying an n-type well region surface in the second active region; and a power supply wiring coupled with the n-type semiconductor region. The dummy gate electrode layer is electrically floating.

A semiconductor structure is provided by a process in which two aspect ratio trapping processes are employed. The structure includes a semiconductor substrate portion of a first semiconductor material having a first lattice constant. A plurality of first semiconductor-containing pillar structures of a second semiconductor material having a second lattice constant that is greater than the first lattice constant extend upwards from a surface of the semiconductor substrate portion. A plurality of second semiconductor-containing pillar structures of a third semiconductor material having a third lattice constant that is greater than the first lattice constant extend upwards from another surface of the semiconductor substrate portion. A spacer separates each first semiconductor-containing pillar structure from each second semiconductor-containing pillar structure. Each second semiconductor-containing pillar structure has a width that is different from a width of each first semiconductor-containing pillar structure.

An element isolation trench is formed in a substrate and is formed along each side of a polygon in a planar view. A first trench is formed in the substrate and extends in a direction different from that of any side of the trench. A first-conductivity type region is formed on/over apart located on the side of an end of the first trench in the substrate. Accordingly, when an impurity region that extends in a depth direction in the substrate is formed by forming the trench in the substrate and diagonally implanting an impurity into the trench, the impurity is prevented from being implanted into a side face of a groove such as a groove for element isolation and so forth impurity implantation into the side face of which is not desired.

An integrated circuit includes at least one transistor over a substrate, and a first guard ring disposed around the at least one transistor. The integrated circuit further includes a second guard ring disposed around the first guard ring. The integrated circuit further includes a first doped region disposed adjacent to the first guard ring, the first doped region having a first dopant type. The integrated circuit further includes a second doped region disposed adjacent to the second guard ring, the second doped region having a second dopant type.