A chemical solution cleaning process for removing backside contamination prior to metallization involves selective chemistries of a mixture containing NH.sub.4OH and H.sub.2O.sub.2 that may be diluted to specific concentrations depending upon the topside metal and passivation of a semiconductor wafer, which is applied after removing a topside protection material to protect the topside circuitry.

A laterally diffused metal oxide semiconductor (LDMOS) transistor structure with improved unclamped inductive switching immunity. The LDMOS includes a substrate and an adjacent epitaxial layer both of a first conductivity type. A gate structure is above the epitaxial layer. A drain region and a source region, both of a second conductivity type, are within the epitaxial layer. A channel is formed between the source and drain region and arranged below the gate structure. A body structure of the first conductivity type is at least partially formed under the gate structure and extends laterally under the source region, wherein the epitaxial layer is less doped than the body structure. A conductive trench-like feed-through element passes through the epitaxial layer and contacts the substrate and the source region. The LDMOS includes a tub region of the first conductivity type formed under the source region, and adjacent laterally to and in contact with said body structure and said trench-like feed-through element.

A semiconductor device includes a column portion including a source portion and a drain portion constituted by semiconductors having the same conductivity type, a channel portion provided between the source portion and the drain portion and constituted by a semiconductor having a lower impurity concentration than those of the source portion and the drain portion, and a drift portion provided between the channel portion and the drain portion and constituted by a semiconductor having the same conductivity type as that of the drain portion; and a gate electrode provided at a sidewall of the column portion at the channel portion via an insulating portion and configured to control the current of the channel portion. The diameter of the column portion at the drift portion is larger than the diameter of the column portion at the channel portion and the diameter of the column portion at the source portion.

A semiconductor device includes a semiconductor element having a substrate, a drift layer, a base region, a source region, trench gate structures, an interlayer insulating film, a source electrode, and a drain electrode. The substrate is made of silicon carbide. The drift layer is disposed on the substrate and has an impurity concentration lower than the substrate. The base region is made of silicon carbide and disposed on the drift layer. The source region is made of silicon carbide having an impurity concentration higher than the drift layer. Each trench gate structure has a gate trench, a gate insulating film, and a gate electrode. The interlayer insulating film covers the gate electrode and the gate insulating film. The source electrode is in ohmic-contact with the source region. The drain electrode is disposed on a rear surface of the substrate.

A semiconductor device includes a semiconductor body having first and second opposite sides, a drift region, a body layer at the second side, and a field-stop region in Ohmic connection with the body layer. A source metallization at the second side is in Ohmic connection with the body layer. A drain metallization at the first side is in Ohmic connection with the drift region. A gate electrode at the second side is electrically insulated from the semiconductor body to define an operable switchable channel region in the body layer. A through contact structure extends at least between the first and second sides, and includes a conductive region in Ohmic connection with the gate electrode and a dielectric layer. In a normal projection onto a horizontal plane substantially parallel to the first side, the field-stop region surrounds at least one of the drift region and the gate electrode.

A semiconductor device includes a region of semiconductor material having a first side and a second side opposite to the first side. Active device structures are adjacent to the first side, the active device structures comprising source regions and gate electrodes. A first gate conductor is at the first side electrically connected to the gate electrodes, a drain region is at the second side, a second gate conductor is at the second side, and through-semiconductor vias extending from the first side towards the side and electrically connecting the first gate electrode to the second gate electrode. A source electrode is at the first side electrically connected to the source regions, and a drain electrode is at the second side electrically connected to the drain region. The through-semiconductor vias are electrically isolated from the source regions and the drain region. The structure provides a gate/drain up with a source-down configuration.

A vertical semiconductor device is formed in a semiconductor layer having a first surface, a second surface and background doping. A first doped region, doped to a conductivity type opposite that of the background, is formed at the second surface of the semiconductor layer. A second doped region of the same conductivity type as the background is formed at the second surface of the semiconductor layer, inside the first doped region. A portion of the semiconductor layer is removed at the first surface, exposing a new third surface. A third doped region is formed inside the semiconductor layer at the third surface. Electrical contact is made at least to the second doped region (via the second surface) and the third doped region (via the new third surface). In this way, vertical DMOS, IGBT, bipolar transistors, thyristors, and other types of devices can be fabricated in thinned semiconductor, or SOI layers.

A semiconductor device includes a semiconductor substrate having a first surface, first and second field plate structures extending in a first direction parallel to the first surface, a plurality of gate electrode structures disposed over the first surface and extending in a second direction parallel to the first surface, the second direction being different than the first direction, and a plurality of source regions and drain regions of a first conductivity type arranged in an alternating manner at the first surface so that a drain region is disposed on one side of a gate electrode structure and a source region is disposed on the other side of the gate electrode structure. The gate electrode structures are disposed between the first and the second field plate structures. The source regions and the drain regions extend in parallel with one another along the second direction.

A semiconductor device having a low feedback capacitance and a low switching loss. The semiconductor device includes: a substrate; a drift layer formed on a surface of the semiconductor substrate; a plurality of first well regions formed on a surface of the drift layer; a source region which is an area formed on a surface of each of the first well regions and defining, as a channel region, the surface of each of the first well regions interposed between the area and the drift layer; a gate electrode formed over the channel region and the drift layer thereacross through a gate insulating film; and second well regions buried inside the drift layer below the gate electrode and formed to be individually connected to each of the first well regions adjacent to one another.

A method comprises providing a substrate with a second conductivity type, growing a first epitaxial layer having the second conductivity type, growing a second epitaxial layer having a first conductivity type, forming a trench in the first epitaxial layer and the second epitaxial layer, forming a gate electrode in the trench, applying an ion implantation process using first gate electrode as an ion implantation mask to form a drain-drift region, forming a field plate in the trench, forming a drain region in the second epitaxial layer, wherein the drain region has the first conductivity type and forming a source region in the first epitaxial layer, wherein the source region has the first conductivity type, and wherein the source region is electrically coupled to the field plate.