A semiconductor device including a well resistance element of high accuracy and high withstand voltage and a method of manufacturing the semiconductor device are provided. The semiconductor device includes a semiconductor substrate, a well region, an input terminal, an output terminal, a separation insulating film, and an active region. The input terminal and the output terminal are electrically coupled to the well region. The separation insulating film is arranged to be in contact with the upper surface of the well region in an intermediate region between the input terminal and the output terminal. The active region is arranged to be in contact with the upper surface of the well region. The separation insulating film and the active region in the intermediate region have an elongated shape in plan view. In the intermediate region, a plurality of separation insulating films and a plurality of active regions are alternately and repeatedly arranged.

In a non-insulated DC-DC converter having a circuit in which a power MOSFET high-side switch and a power MOSFET low-side switch are connected in series, the power MOSFET low-side switch and a Schottky barrier diode to be connected in parallel with the power MOSFET low-side switch are formed within one semiconductor chip. The formation region SDR of the Schottky barrier diode is disposed in the center in the shorter direction of the semiconductor chip, and on both sides thereof, the formation regions of the power MOSFET low-side switch are disposed. From the gate finger in the vicinity of both long sides on the main surface of the semiconductor chip toward the formation region SDR of the Schottky barrier diode, a plurality of gate fingers are disposed so as to interpose the formation region SDR between them.

A trench type power semiconductor device with improved breakdown voltage and UIS performance and a method for preparation the device are disclosed. The trench type power semiconductor device includes a first contact hole formed in a mesa in the active area and a second contact hole formed in a mesa in an active to termination intermediate area, where the first contact hole is deeper and wider than the second contact hole. The method comprises the steps of providing a semiconductor substrate, etching an epitaxial layer, depositing a conductive material, depositing an insulation passivation layer and etching through the insulation passivation layer.

A semiconductor power device may include a lightly doped layer formed on a heavily doped layer. One or more devices are formed in the lightly doped layer. Each device includes a body region, a source region, and one or more gate electrodes formed in corresponding trenches in the lightly doped region. Each trench has a first dimension (depth), a a second dimension (width) and a third dimension (length). The body region is of opposite conductivity type to the lightly and heavily doped layers. An opening is formed between first and second trenches through an upper portion of the source region and a body contact region to the body region. A deep implant region of the second conductivity type is formed in the lightly doped layer below the body region. The deep implant region is vertically aligned to the opening and spaced away from a bottom of the opening.

A semiconductor device includes a semiconductor body with transistor cells arranged in an active area and absent in an edge area between the active area and a side surface. A field dielectric adjoins a first surface of the semiconductor body and separates, in the edge area, a conductive structure connected to gate electrodes of the transistor cells from the semiconductor body. The field dielectric includes a transition from a first vertical extension to a second, greater vertical extension. The transition is in the vertical projection of a non-depletable extension zone in the semiconductor body, wherein the non-depletable extension zone has a conductivity type of body/anode zones of the transistor cells and is electrically connected to at least one of the body/anode zones.

A semiconductor device having a vertical drain extended MOS transistor may be formed by forming deep trench structures to define vertical drift regions of the transistor, so that each vertical drift region is bounded on at least two opposite sides by the deep trench structures. The deep trench structures are spaced so as to form RESURF regions for the drift region. Trench gates are formed in trenches in the substrate over the vertical drift regions. The body regions are located in the substrate over the vertical drift regions.

In an embodiment, a semiconductor device includes a semiconductor substrate having a bulk resistivity 100 Ohm.cm, a front surface and a rear surface, at least one LDMOS transistor in the semiconductor substrate, and a RESURF structure. The RESURF structure includes a doped buried layer arranged in the semiconductor substrate, spaced at a distance from the front surface and the rear surface, and coupled with at least one of a channel region and a body contact region of the LDMOS transistor.

Switch devices using switch transistors with dual gates are provided. The dual gates may be controlled independently from each other by first and second gate driver circuits.

A semiconductor device provided herein includes: a fourth region of a p-type being in contact with a lower end of the gate trench; a termination trench provided in the front surface in a range outside the second region; a lower end p-type region of the p-type being in contact with a lower end of the termination trench; a lateral p-type region of the p-type being in contact with a lateral surface of the termination trench on an outer circumferential side, connected to the lower end p-type region, and exposed on the front surface; and a plurality of guard ring regions provided on the outer circumferential side with respect to the lateral p-type region and exposed on the front surface.

A semiconductor device having a low on-voltage of IGBT and a small reverse recovery current of the diode is provided. The semiconductor device includes a semiconductor substrate having a gate trench and a dummy trench. The semiconductor substrate includes emitter, body, barrier and pillar regions between the gate trench and the dummy trench. The emitter region is an n-type region being in contact with the gate insulating film and exposed on a front surface. The body region is a p-type region being in contact with the gate insulating film at a rear surface side of the emitter region. The barrier region is an n-type region being in contact with the gate insulating film at a rear surface side of the body region and in contact with the dummy insulating film. The pillar region is an n-type region connected to the front surface electrode and the barrier region.