We disclose a bi-directional bipolar junction transistor (BJT) structure, comprising: a base region of a first conductivity type, wherein said base region constitutes a drift region of said structure; first and second collector/emitter (CE) regions, each of a second conductivity type adjacent opposite ends of said base region; wherein said base region is lightly doped relative to said collector/emitter regions; the structure further comprising: a base connection to said base region, wherein said base connection is within or adjacent to said first collector/emitter region.

A semiconductor device includes a first conductivity type semiconductor substrate, a second conductivity type first and second buried diffusion layers that are arranged in the semiconductor substrate, a semiconductor layer arranged on the semiconductor substrate, a second conductivity type first impurity diffusion region that is arranged in the semiconductor layer, a second conductivity type second impurity diffusion region that is arranged, in the semiconductor layer, on the second buried diffusion layer, a second conductivity type first well that is arranged in a first region of the semiconductor layer, a first conductivity type second well that is arranged, in the semiconductor layer, in a second region, a first conductivity type third and fourth impurity diffusion regions that are arranged in the first well, and a first conductivity type fifth impurity diffusion region that is arranged in the second well.

A semiconductor device is provided in which a zener diode having a desired breakdown voltage and a capacitor in which voltage dependence of capacitance is reduced are mounted together, and various circuits are realized. The semiconductor device includes: a semiconductor layer; a first conductivity type well that is arranged in a first region of the semiconductor layer; a first conductivity type first impurity diffusion region that is arranged in the well; a first conductivity type second impurity diffusion region that is arranged in a second region of the semiconductor layer; an insulating film that is arranged on the second impurity diffusion region; an electrode that is arranged on the insulating film; and a second conductivity type third impurity diffusion region that is arranged at least on the first impurity diffusion region.

A bipolar junction transistor includes a first well region having a first conductive type, a second well region disposed adjacent to the first well region and having a second conductive type, an emitter disposed on the first well region and having the second conductive type, a base disposed on the first well region and having the first conductive type, a collector disposed on the second well region and having the second conductive type, and device isolation regions disposed among the emitter, the base and the collector. Particularly, the emitter, the base and the collector are spaced apart from the device isolation regions.

A semiconductor device and a process to form the same are disclosed. The semiconductor device includes a support, an active semiconductor stack including a first semiconductor layer, a second semiconductor layer, and a third semiconductor layer, the first to third semiconductor layers being sequentially stacked on the support, and an electrode on the third semiconductor layer. The first semiconductor layer and the second semiconductor layer provide a buried region in a portion under the electrode, the buried region being filled with a material having a first dielectric constant smaller than a second dielectric constant of the first semiconductor layer and a third dielectric constant of the second semiconductor layer.

A vertical semiconductor device (e.g. a vertical power device, an IGBT device, a vertical bipolar transistor, a UMOS device or a GTO thyristor) is formed with an active semiconductor region, within which a plurality of semiconductor structures have been fabricated to form an active device, and below which at least a portion of a substrate material has been removed to isolate the active device, to expose at least one of the semiconductor structures for bottom side electrical connection and to enhance thermal dissipation. At least one of the semiconductor structures is preferably contacted by an electrode at the bottom side of the active semiconductor region.

According to various embodiments, a bipolar transistor structure may include: a substrate; a collector region in the substrate; a base region disposed over the collector region, an emitter region disposed over the base region; a base terminal laterally electrically contacting the base region, wherein the base terminal includes polysilicon.

The present disclosure relates to a vertical bipolar junction transistor. A vertical bipolar junction transistor includes a high concentration doping region emitter terminal disposed on a semiconductor substrate; a high concentration doping region collector terminal disposed on a semiconductor substrate; a high concentration doping region base terminal disposed between the emitter terminal and the collector terminal; a drift region having a first doping concentration surrounding the emitter terminal and being deeper than either the base terminal or the collector terminal; a base layer disposed below the drift region; a collector layer in contact with the base layer, the collector layer having a second doping concentration higher than the first doping concentration. The manufacturing cost of the vertical bipolar junction transistor can be lowered and a current gain can be elevated using a low-cost BCD process.

A two-transistor memory cell based upon a thyristor 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.

The present application teaches, inter alia, methods and circuits for operating B-TRANs (double-base bidirectional bipolar junction transistors). Base drive circuits provide high-impedance drive to the base contact region on whichever side of the device is (instantaneously) operating as the collector. (B-TRANs, unlike other bipolar junction transistors, are controlled by applied voltage, not applied current.) Control signals operate preferred drive circuits, providing diode-mode turn-on and pre-turnoff operation, and a hard ON state with a low voltage drop (the transistor-ON state). In some (not necessarily all) preferred embodiments, a self-synchronizing rectifier circuit provides an adjustable low voltage for the gate drive circuit. Also, in some preferred embodiments, the base drive voltage used to drive the c-base region (on the collector side) is varied while monitoring the base current at that terminal, so that no more base current than necessary is applied. This solves the difficult challenge of optimizing base drive in B-TRANs.