A performance of a semiconductor device including an RC-IGBT is improved. An AlNiSi layer (a layer containing aluminum (Al), nickel (Ni), and silicon (Si)) is formed between a back surface of a semiconductor substrate and a back surface electrode. Thus, a favorable ohmic junction can be obtained between the back surface electrode and an N.sup.+-type layer constituting a cathode region in an embedded diode, and a favorable ohmic junction can be obtained between the back surface electrode and a P-type layer constituting a collector region in an IGBT. The AlNiSi layer contains 10 at % or more of each of the aluminum (Al), the nickel (Ni), and the silicon (Si).

A semiconductor device according to the present invention includes a semiconductor substrate, having an emitter layer of a first conductivity type, a collector layer of a second conductivity type and a drift layer of the first conductivity type sandwiched therebetween, the emitter layer disposed at a front surface side of the semiconductor substrate and the collector layer disposed at a rear surface side of the semiconductor substrate, a base layer of the second conductivity type between the drift layer and the emitter layer, a buffer layer of the first conductivity type between the collector layer and the drift layer, the buffer layer having an impurity concentration higher than that of the drift layer, and having an impurity concentration profile with two peaks in regard to a depth direction from the rear surface of the semiconductor substrate, and a defect layer, formed in the drift layer and having an impurity concentration profile with a half-value width of not more than 2 m in regard to the depth direction from the rear surface of the semiconductor substrate.

A method of processing a semiconductor device is presented. The method includes providing a semiconductor body; forming a trench within the semiconductor body, the trench having a stripe configuration and extending laterally within an active region of the semiconductor body that is surrounded by a non-active region of the semiconductor body; forming, within the trench, a first electrode and a first insulator insulating the first electrode from the semiconductor body; carrying out a first etching step for partially removing the first electrode along the total lateral extension of the first electrode such that the remaining part of the first electrode has a planar surface, thereby creating a well in the trench that is laterally confined by the first insulator; depositing a second insulator on top the planar surface; and forming a second electrode within the well of the trench. The second insulator insulates the second electrode from the first electrode.

Methods of forming a semiconductor device are provided. A method includes introducing impurities into a part of a semiconductor substrate at a first surface of the semiconductor substrate by ion implantation, the impurities being configured to absorb electromagnetic radiation of an energy smaller than a bandgap energy of the semiconductor substrate. The method further includes forming a semiconductor layer on the first surface of the semiconductor substrate. The method further includes irradiating the semiconductor substrate with electromagnetic radiation configured to be absorbed by the impurities and configured to generate local damage of a crystal lattice of the semiconductor substrate. The method further includes separating the semiconductor layer and the semiconductor substrate by thermal processing of the semiconductor substrate and the semiconductor layer, where the thermal processing is configured to cause crack formation along the local damage of the crystal lattice by thermo-mechanical stress.

A semiconductor device includes first and second cell trench structures extending from a first surface into a semiconductor body, a first semiconductor mesa separating the cell trench structures. The first cell trench structure includes a first buried electrode and a first insulator layer. A first vertical section of the first insulator layer separates the first buried electrode from the first semiconductor mesa. The first semiconductor mesa includes a source zone of a first conductivity type directly adjoining the first surface. The semiconductor device further includes a capping layer on the first surface and a contact structure having a first section in an opening of the capping layer and a second section in the first semiconductor mesa or between the first semiconductor mesa and the first buried electrode. A lateral net impurity concentration of the source zone parallel to the first surface increases in the direction of the contact structure.

A reverse-conducting IGBT includes a semiconductor body having a drift region arranged between first and second surfaces. The semiconductor body further includes first collector regions arranged at the second surface and in Ohmic contact with a second electrode, backside emitter regions and in Ohmic contact with the second electrode. In a horizontal direction substantially parallel to the first surface, the first collector regions and backside emitter regions define an rc-IGBT area. The semiconductor body further includes a second collector region of the second conductivity type arranged at the second surface and in Ohmic contact with the second electrode. The second collector region defines in the horizontal direction a pilot-IGBT area. The rc-IGBT area includes first semiconductor regions in Ohmic contact with the first electrode and arranged between the drift region and first electrode. The pilot-IGBT area includes second semiconductor regions of the same conductivity type as the first semiconductor regions.

A compliant bipolar micro device transfer head array and method of forming a compliant bipolar micro device transfer array from an SOI substrate are described. In an embodiment, a compliant bipolar micro device transfer head array includes a base substrate and a patterned silicon layer over the base substrate. The patterned silicon layer may include first and second silicon interconnects, and first and second arrays of silicon electrodes electrically connected with the first and second silicon interconnects and deflectable into one or more cavities between the base substrate and the silicon electrodes.

A semiconductor device has a reduced an on-voltage and uses a gate resistance to improve the trade-off relationship between turn-on loss Eon and dV/dt, and turn-on dV/dt controllability. A floating p.sup.+-type region is provided in an n.sup.-type drift layer so as to be spaced from a p-type base region configuring a MOS gate structure. An emitter electrode and the floating p.sup.+-type region are electrically connected by an n.sup.+-type region provided in the surface layer of a substrate front surface. The n.sup.+-type region is covered with a second insulating film which film is covered with an emitter electrode. By an electric field being generated in the n.sup.+-type region by the emitter electrode provided on the top of the n.sup.+-type region via the second interlayer insulating film, the n.sup.+-type region forms a current path which causes holes accumulated in the floating p.sup.+-type region to flow to the emitter electrode when turning on.

An IGBT device includes a substrate having a bottom semiconductor layer of a first conductivity type and an upper semiconductor layer of a second conductivity type, at least one first gate formed in a corresponding first trench disposed over the substrate, and a second gate formed in a second trench disposed over the bottom semiconductor layer. The first and second trenches are provided with gate insulators on each side of the trenches and filled with polysilicon. The second trench extends vertically to depth deeper than the at least one first trench. The IGBT device further includes a body region of the first conductivity type provided between the at least one first gate and/or the second gate, and at least one stacked layer provided between a bottom of the at least one first gate and a top of the upper semiconductor layer. The at least one stacked layer includes a floating body region of the second conductivity type provided on top of a floating body region of the first conductivity type. It is emphasized that this abstract is provided to comply with rules requiring an abstract that will allow a searcher or other reader to quickly ascertain the subject matter of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims.

A semiconductor device includes a gate trench in a semiconductor substrate, a source trench in the semiconductor substrate, the source trench having a first portion and a second portion under the first portion, where the first portion of the source trench is wider than the gate trench, and extends to a depth of the gate trench. The semiconductor device also includes a gate electrode and a gate trench dielectric liner in the gate trench, and a conductive filler and a source trench dielectric liner in the source trench. The semiconductor device further includes a source region between the gate trench and the source trench, a base region between the gate trench and the source trench, and a source contact coupled to the source region and the base region.