The present application teaches, among other innovations, methods and circuits for operating a B-TRAN (double-base bidirectional bipolar junction transistor). A base drive circuit is described which provides high-impedance drive to the base contact region on whichever side of the device is operating as the collector (at a given moment). (The B-TRAN, unlike other bipolar junction transistors, is controlled by applied voltage rather than applied current.) The preferred implementation of the drive circuit is operated by control signals to provide diode-mode turn-on and pre-turnoff operation, as well as a hard ON state with a low voltage drop (the transistor-ON state). In some but not necessarily all preferred embodiments, an adjustable low voltage for the gate drive circuit is provided by a self-synchronizing rectifier circuit. Also, in some but not necessarily all preferred embodiments, the base drive voltage used to drive the c-base region (on the collector side) is varied while the base current at that terminal is monitored, so that no more base current than necessary is applied. This solves the difficult challenge of optimizing base drive in a B-TRAN.

An approach for heat dissipation in integrated circuit devices is provided. A method includes forming an isolation layer on an electrically conductive feature of an integrated circuit device. The method also includes forming an electrically conductive layer on the isolation layer. The method additionally includes forming a plurality of nanowire structures on a surface of the electrically conductive layer.

An insulated gate bipolar transistor (IGBT) includes a gate trench, an emitter trench, and an electrically insulative layer coupled to the emitter trench and the gate trench and electrically isolating the gate trench from an electrically conductive layer. A contact opening in the electrically insulative layer extends into the emitter trench and the electrically conductive layer electrically couples with the emitter trench therethrough. A P surface doped (PSD) region and an N surface doped (NSD) region are each located between the electrically conductive layer and a plurality of semiconductor layers of the IGBT and between the gate trench and the emitter trench. The electrically conductive layer electrically couples to the plurality of semiconductor layers through the PSD region and/or the NSD region.

A semiconductor device includes: metal collector layer on backside, P-type collector layer, N-type field stop layer and N drift layer. There are active cells and dummy cells on top of the device. The active cell and dummy cell are separated by gate trench. The gate trench is formed by polysilicon and gate oxide layer. There are N+ region and P+ region in active cells, and they are connected to metal emitter layer through the window in the insulation layer. There are P-well regions in both active cells and dummy cells. The P-well regions in active cells are continuous and connected to emitter electrode through P+ region. The P-well regions in dummy cells are discontinuous and electrically floating.

A semiconductor device includes: a semiconductor substrate, an upper electrode, a lower electrode and a gate electrode. In the semiconductor substrate, a body region, a pillar region, and a barrier region are formed. The pillar region has an n-type impurity, is formed on a lateral side of the body region, and extends along a depth from a top surface of the semiconductor substrate to a lower end of the body region. The barrier region has an n-type impurity and is formed on a lower side of the body region and the pillar region. The barrier region is formed on the lower side of the pillar region. An n-type impurity concentration distribution in a depth direction in the pillar region and the barrier region has a maximum value in the pillar region. The n-type impurity concentration distribution has a folding point on a side deeper than the maximum value.

A semiconductor device includes a semiconductor substrate having an active layer in which an element region and a contact region are formed, a support substrate supporting the active layer, and a buried insulation layer interposed between the active layer and the support substrate. A transistor element is formed in the element region, the transistor element having a transistor buried impurity layer formed within the active layer. The semiconductor device further includes a substrate contact having a contact buried impurity layer formed within the contact region and a through contact extending from the surface of the active layer to the support substrate through the contact buried impurity and the buried insulation layer, the contact buried impurity layer being in the same layer as the transistor buried impurity layer.

A semiconductor device includes a semiconductor chip formed with an SiC-IGBT including an SiC semiconductor layer, a first conductive-type collector region formed such that the collector region is exposed on a second surface of the SiC semiconductor layer, a second conductive-type base region formed such that the base region contacts the collector region, a first conductive-type channel region formed such that the channel region contacts the base region, a second conductive-type emitter region formed such that the emitter region contacts the channel region to define a portion of a first surface of the SiC semiconductor layer, a collector electrode connected to the collector region, and an emitter electrode connected to the emitter region. A MOSFET of the device is connected in parallel to the SiC-IGBT, and includes a second conductive-type source region electrically connected to the emitter electrode and a second conductive-type drain region electrically connected to the collector electrode.

A memory cell based upon thyristors for an SRAM integrated circuit is described together with a process for fabricating it. The memory cell can be implemented in different combinations of MOS and bipolar select transistors, or without select transistors, with thyristors in a semiconductor substrate with shallow trench isolation. Standard CMOS process technology can be used to manufacture the SRAM. Special circuitry provides lowered power consumption during standby.

The present application provides (in addition to more broadly applicable inventions) improvements which are particularly applicable to two-sided power semiconductor devices which use bipolar conduction. In this class of devices, the inventor has realized that two or three of the four (or more) semiconductor doping components which form the carrier-emission structures and control structures in the active device (array) portion of a two-sided power device can also be used, with surprising advantages, to form field-limiting rings around the active arrays on both surfaces. Most preferably, in some but not necessarily all embodiments, a shallow implant of one conductivity type is used to counterdope the surface of a well having the other conductivity type. This shallow implant, singly or in combination with another shallow implant of the same conductivity type, works to shield the well from the effects of excess charge at or above the surface of the semiconductor material.

A switching loss is prevented from being deteriorated by suppressing increase in a gate capacitance due to a cell shrink of an IE type trench gate IGBT. A cell formation region is configured of a linear active cell region, a linear hole collector cell region, and a linear inactive cell region between them. Then, upper surfaces of the third and fourth linear trench gate electrodes which are formed so as to sandwich both sides of the linear hole collector cell region and electrically connected to an emitter electrode are positioned to be lower than upper surfaces of the first and second linear trench gate electrodes which are formed so as to sandwich both sides of the linear active cell region and electrically connected to a gate electrode.