Most semiconductor devices manufactured today, have uniform dopant concentration, either in the lateral or vertical device active (and isolation) regions. By grading the dopant concentration, the performance in various semiconductor devices can be significantly improved. Performance improvements can be obtained in application specific areas like increase in frequency of operation for digital logic, various power MOSFET and IGBT ICS, improvement in refresh time for DRAM's, decrease in programming time for nonvolatile memory, better visual quality including pixel resolution and color sensitivity for imaging ICs, better sensitivity for varactors in tunable filters, higher drive capabilities for JFET's, and a host of other applications.

A silicon carbide semiconductor device has a silicon carbide substrate, a gate insulating film, and a gate electrode. Silicon carbide substrate includes a first impurity region having a first conductivity type, a well region being in contact with the first impurity region and having a second conductivity type which is different from the first conductivity type, and a second impurity region separated from the first impurity region by the well region and having the first conductivity type. The gate insulating film is in contact with the first impurity region and the well region. The gate electrode is in contact with the gate insulating film and is arranged opposite to the well region with respect to the gate insulating film. A specific on-resistance at a voltage which is half a gate driving voltage applied to the gate electrode is smaller than twice the specific on-resistance at the gate driving voltage.

An igniter is not provided with a depression IGBT and is configured such that a distance between a main IGBT and a sense IGBT is equal to or greater than 100 m and equal to or less than 700 m and preferably equal to or greater than 100 m and equal to or less than 200 m. The igniter is controlled such that, before the overcurrent of the main IGBT reaches a predetermined upper limit, a sense current of the sense IGBT is saturated. Therefore, it is possible to provide the igniter which has a small size and prevents the overshoot of a collector current of the main IGBT when a current is limited and an internal combustion engine ignition apparatus which includes the igniter, has a small size, and prevents an ignition error.

Methods, systems, circuits, and devices for power-packet-switching power converters using bidirectional bipolar transistors (BTRANs) for switching. Four-terminal three-layer BTRANs provide substantially identical operation in either direction with forward voltages of less than a diode drop. BTRANs are fully symmetric merged double-base bidirectional bipolar opposite-faced devices which operate under conditions of high non-equilibrium carrier concentration, and which can have surprising synergies when used as bidirectional switches for power-packet-switching power converters. BTRANs are driven into a state of high carrier concentration, making the on-state voltage drop very low.

A method of producing a semiconductor device is presented. The method comprises: providing a semiconductor substrate having a surface; epitaxially growing, along a vertical direction (Z) perpendicular to the surface, a back side emitter layer on top of the surface, wherein the back side emitter layer has dopants of a first conductivity type or dopants of a second conductivity type complementary to the first conductivity type; epitaxially growing, along the vertical direction (Z), a drift layer having dopants of the first conductivity type above the back side emitter layer, wherein a dopant concentration of the back side emitter layer is higher than a dopant concentration of the drift layer; and creating, either within or on top of the drift layer, a body region having dopants of the second conductivity type, a transition between the body region and the drift layer forming a pn-junction (Zpn). Epitaxially growing the drift layer includes creating, within the drift layer, a dopant concentration profile (P) of dopants of the first conductivity type along the vertical direction (Z), the dopant concentration profile (P) in the drift layer exhibiting a variation of a concentration of dopants of the first conductivity type along the vertical direction (Z).

A semiconductor device includes transistor cells formed along a first surface at a front side of a semiconductor body in a transistor cell area. A drift zone structure forms first pn junctions with body zones of the transistor cells. An auxiliary structure between the drift zone structure and a second surface at a rear side of the semiconductor body includes a first portion that contains deep level dopants requiring at least 150 meV to ionize. A collector structure directly adjoins the auxiliary structure. An injection efficiency of minority carriers from the collector structure into the drift zone structure varies along a direction parallel to the first surface at least in the transistor cell area.

A semiconductor device in which short circuit capability can be improved while decline in overall current capability is suppressed. In the semiconductor device, a plurality of IGBTs (insulated gate bipolar transistors) arranged in a row in one direction over the main surface of a semiconductor substrate include an IGBT located at an extreme end in the one direction and an IGBT located more centrally than the IGBT located at the extreme end. The current capability of the IGBT located at the extreme end is higher than the current capability of the IGBT located centrally.

A semiconductor chip has a semiconductor body with a bottom side and a top side arranged distant from the bottom side in a vertical direction, an active and a non-active transistor region, a drift region formed in the semiconductor body, a contact terminal for externally contacting the semiconductor chip, and a plurality of transistor cells formed in the semiconductor body. Each of the transistor cells has a first electrode. Each of a plurality of connection lines electrically connects another one of the first electrodes to the contact terminal pad at a connecting location of the respective connection line. Each of the connection lines includes a resistance section formed of a locally increased specific resistance relative to a specific resistance of adjacent semiconductor material or metal of the respective connection line. Each of the connecting locations and each of the resistance sections is arranged in the non-active transistor region.

Performance of a semiconductor device is improved without increasing an area size of a semiconductor chip. For example, a source electrode of a power transistor and an upper electrode of a capacitor element have an overlapping portion. In other word, the upper electrode of the capacitor element is formed over the source electrode of the power transistor through a capacitor insulating film. That is, the power transistor and the capacitor element are arranged in a laminated manner in a thickness direction of the semiconductor chip. As a result, it becomes possible to add a capacitor element to be electrically coupled to the power transistor while suppressing an increase in planar size of the semiconductor chip.

Disclosed is a method for producing a transistor device and a transistor device. The method includes: forming a source region of a first doping type in a body region of a second doping type in a semiconductor body; and forming a low-resistance region of the second doping type adjoining the source region in the body region. Forming the source region includes implanting dopant particles of the first doping type using an implantation mask via a first surface of the semiconductor body into the body region. Implanting the doping particles of the first doping type includes a tilted implantation.