An integrated circuit contains a logic MOS transistor and a memory MOS transistor of a same polarity. The logic MOS transistor has a logic channel stop layer. The memory MOS transistor has a memory channel stop layer. An average dopant density of the memory channel stop layer is higher than an average dopant density of the logic channel stop layer. The integrated circuit is formed by forming a global mask which exposes both the logic and memory MOS transistors. A global channel stop dose of dopants is implanted in the logic and memory MOS transistors. A memory mask is formed which exposes the memory MOS transistor and covers the logic MOS transistor. A memory channel stop dose of dopants of the same polarity is implanted into the memory MOS transistors. The memory channel stop dose of dopants are blocked from the logic MOS transistors.

Methods of according to the present disclosure can include: providing a substrate including: a first semiconductor region, a second semiconductor region, and a trench isolation (TI) laterally between the first and second semiconductor regions; forming a seed layer on the TI and the second semiconductor region of the substrate, leaving the first semiconductor region of the substrate exposed; forming an epitaxial layer on the substrate and the seed layer, wherein the epitaxial layer includes: a first semiconductor base material positioned above the first semiconductor region of the substrate, and an extrinsic base region positioned above the seed layer; forming an opening within the extrinsic base material and the seed layer to expose an upper surface of the second semiconductor region; and forming a second semiconductor base material in the opening.

Various particular embodiments include an integrated circuit (IC) structure having: a stack region; and a silicon substrate underlying and contacting the stack region, the silicon substrate including: a silicon region including a doped subcollector region; a set of isolation regions overlying the silicon region; a base region between the set of isolation regions and below the stack region, the base region including an intrinsic base contacting the stack region, an extrinsic base contacting the intrinsic base and the stack region, and an amorphized extrinsic base contact region contacting the extrinsic base; a collector region between the set of isolation regions; an undercut collector-base region between the set of isolation regions and below the base region; and a collector contact region contacting the collector region under the intrinsic base and the collector-base region via the doped subcollector region.

Device structures and fabrication methods for a device structure. One or more trench isolation regions are formed in a substrate to surround a device region. A base layer is formed on the device region. First and second emitter fingers are formed on the base layer. A portion of the device region extending from the first emitter finger to the second emitter finger is free of dielectric material.

Complementary high-voltage bipolar transistors formed in standard bulk silicon integrated circuits are disclosed. In one disclosed embodiment, collector regions are formed in an epitaxial silicon layer. Base regions and emitters are disposed over the collector region. An n-type region is formed under collector region by implanting donor impurities into a p-substrate for the PNP transistor and implanting acceptor impurities into the p-substrate for the NPN transistor prior to depositing the collector epitaxial regions. Later in the process flow these n-type and p-type regions are connected to the top of the die by a deep n+ and p+ wells respectively. The n-type well is then coupled to VCC while the p-type well is coupled to GND, providing laterally depleted portions of the PNP and NPN collector regions and hence, increasing their BVs.

A bipolar junction semiconductor device and associated method of manufacturing, the bipolar junction semiconductor device has a P type substrate, a N type buried layer formed in the substrate, a P type first epitaxial layer formed on the buried layer, a P type second epitaxial layer formed on the first epitaxial layer, a PNP BJT unit formed in the first and second epitaxial layers at a first active area, a NPN BJT unit formed in the first and second epitaxial layers at a second active area and a first isolation structure of N type formed in the first and second epitaxial layers at an isolation area. The isolation area is located between the first active area and the second active area, the first isolation structure connected with the buried layer forms an isolation barrier.

An integrated circuit of the BiCMOS type includes at least one vertical junction field-effect transistor. The vertical junction field-effect transistor is formed to include a channel region having a critical dimension of active surface that is controlled by photolithography.

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.

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.

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.