Various embodiments of the present disclosure are directed towards a method for forming a bipolar junction transistor (BJT). A dielectric film is deposited over a substrate and comprises a lower dielectric layer, an upper dielectric layer, and an intermediate dielectric layer between the lower and upper dielectric layers. A first semiconductor layer is deposited over the dielectric film and is subsequently patterned to form an opening exposing the dielectric film. A first etch is performed into the upper dielectric layer through the opening to extend the opening to the intermediate dielectric layer. Further, the first etch stops on the intermediate dielectric layer and laterally undercuts the first semiconductor layer. Additional etches are performed to extend the opening to the substrate. A lower base structure and an emitter are formed stacked in and filling the opening, and the first semiconductor layer is patterned to form an upper base structure.

A bipolar junction transistor is provided with an emitter structure that is positioned above the upper surface of the base region. The thickness of the emitter and the interfacial oxide thickness between the emitter and the base is configured to optimize a gain for a given type of transistor. A method of fabricating PNP and NPN transistors on the same substrate using a complementary bipolar fabrication process is provided. The method enables the emitter structure for the NPN transistor to be defined separately to that of the PNP transistor. This is achieved by epitaxially growing the emitter layer for the PNP transistor and growing the emitter layer for the NPN transistor in a thermal furnace.

A semiconductor device or circuit includes a vertical bipolar junction transistor (vBJT) and a vertical filed effect transistor (vFET). The vBJT collector is electrically and/or physically connected to an adjacent vFET source. For example, a vBJT collector and a vFET source may be integrated upon a same semiconductor material substrate or layer. The vFET provides negative feedback for the collector-base voltage and the vBJT emitter and collector allow for low transit times.

A microelectronic device includes a PNP transistor and NPN transistor arranged vertically in a P-type doped semiconductor substrate. The PNP and NPN transistors are manufactured by: forming an N+ doped isolating well for the PNP transistor in the semiconductor substrate; forming a P+ doped region in the N+ doped isolating well; epitaxially growing a first semiconductor layer on the semiconductor substrate; forming an N+ doped well for the NPN transistor, where at least part of the N+ doped well extends into the first semiconductor layer; then epitaxially growing a second semiconductor layer on the first semiconductor layer; forming a P doped region forming the collector of the PNP transistor in the second semiconductor layer and in electrical contact with the P+ doped region; and forming an N doped region forming the collector of the NPN transistor in the second semiconductor layer and in electrical contact with the N+ doped well.

A microelectronic device includes a PNP transistor and NPN transistor arranged vertically in a P-type doped semiconductor substrate. The PNP and NPN transistors are manufactured by: forming an N+ doped isolating well for the PNP transistor in the semiconductor substrate; forming a P+ doped region in the N+ doped isolating well; epitaxially growing a first semiconductor layer on the semiconductor substrate; forming an N+ doped well for the NPN transistor, where at least part of the N+ doped well extends into the first semiconductor layer; then epitaxially growing a second semiconductor layer on the first semiconductor layer; forming a P doped region forming the collector of the PNP transistor in the second semiconductor layer and in electrical contact with the P+ doped region; and forming an N doped region forming the collector of the NPN transistor in the second semiconductor layer and in electrical contact with the N+ doped well.

A semiconductor device or circuit includes a vertical bipolar junction transistor (vBJT) and a vertical filed effect transistor (vFET). The vBJT collector is electrically and/or physically connected to an adjacent vFET source. For example, a vBJT collector and a vFET source may be integrated upon a same semiconductor material substrate or layer. The vFET provides negative feedback for the collector-base voltage and the vBJT emitter and collector allow for low transit times.

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.

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.

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 six-transistor memory cell based upon a thyristor for an SRAM integrated circuit is described together with methods of operation. Methods of increasing the operational speed in reading the contents of a selected memory cell in an array of such memory cells while lowering power consumption, and of avoiding an indeterminate memory cell state when a memory cell is “awakened” from Standby are described.