Abstract: According to one exemplary embodiment, a method for forming an NPN and a vertical PNP device on a substrate comprises forming an insulating layer over an NPN region and a PNP region of the substrate. The method further comprises forming a buffer layer on the insulating layer and forming an opening in the buffer layer and the insulating layer in the NPN region, where the opening exposes the substrate. The method further comprises forming a semiconductor layer on the buffer layer and in the opening in the NPN region, where the semiconductor layer has a first portion situated in the opening and a second portion situated on the buffer layer in the PNP region. The first portion of the semiconductor layer forms a single crystal base of the NPN device and the second portion of the semiconductor layer forms a polycrystalline emitter of the vertical PNP device.

Abstract: A heterojunction bipolar transistor (30) in a silicon-on-insulator (SOI) structure is disclosed. The transistor collector (28), heterojunction base region (20), and intrinsic emitter region (25) are formed in the thin film silicon layer (6) overlying the buried insulator layer (4). A base electrode (10) is formed of polysilicon, and has a polysilicon filament (10f) that extends over the edge of an insulator layer (8) to contact the silicon layer (6). After formation of insulator filaments (12) along the edges of the base electrode (10) and insulator layer (8), the thin film silicon layer (6) is etched through, exposing an edge. An angled ion implantation then implants the heterojunction species, for example germanium and carbon, into the exposed edge of the thin film silicon layer (6), which after anneal forms the heterojunction base region (20).

Abstract: The present invention provides a unique device structure and method that provides increased transistor performance in integrated bipolar circuit devices. The preferred embodiment of the present invention provides improved high speed performance by providing reduced base resistence. The preferred design forms the extrinsic base by diffusing dopants from a dopant source layer and into the extrinsic base region. This diffusion of dopants forms at least a portion of the extrinsic base. In particular, the portion adjacent to the intrinsic base region is formed by diffusion. This solution avoids the problems caused by traditional solutions that implanted the extrinsic base. Specifically, by forming at least a portion of the extrinsic base by diffusion, the problem of damage to base region is minimized. This reduced damage enhances dopant diffusion into the intrinsic base. Additionally, the formed extrinsic base can have improved resistence, resulting in an improved maximum frequency for the bipolar device.

Abstract: A semiconductor device includes a low resistance semiconductor substrate, a high resistance semiconductor layer formed on the substrate, an insulation layer formed on the semiconductor layer, and a transistor element composed of a collector region, abase region, and an emitter region formed in the semiconductor layer. The device further includes an emitter electrode formed in the insulation layer to be connected to the emitter region, a sub-emitter electrode formed in the insulation layer connected to the emitter electrode, a low resistance impurity-diffusion region formed in the semiconductor layer such that the sub-emitter electrode is connected to the substrate through the impurity-diffusion region, a base electrode formed in the insulation layer to be connected to the base region, and a base-bonding pad formed on the insulation layer to be connected to the base electrode.

Abstract: A method of manufacturing a bipolar junction transistor results in an integrated polysilicon base contact and field plate element minimally spaced from a polysilicon emitter contact by using a single mask to define respective openings for these elements. In particular, a dielectric layer is deposited on a semiconductor wafer and has two openings defined by a single masking step, one opening above an emitter region and a second opening above a base-collector junction region. Polysilicon is deposited on the dielectric layer and selectively doped in the areas of the openings. Thus for an NPN transistor for example, the area above the emitter opening is doped N type and the area above the base/field plate opening is doped P type. The doped polysilicon is patterned and etched to leave a polysilicon emitter contact and an integrated polysilicon base contact and field plate within the respective openings.

Abstract: A heterojunction bipolar transistor with self-aligned features having a self-aligned dielectric sidewall spacer disposed between base contact and emitter contact, and self-aligned base mesa aligned relative to self-aligned base contact. The base contact is self-aligned relative to the self-aligned dielectric sidewall spacer providing a predetermined base-to-emitter spacing thereby. The emitter may be an n-type, InP material; the base can be a p-type InGaAs material, possibly carbon-doped. The fabrication method includes forming a emitter electrode on an emitter layer; using the emitter contact as a mask, anisotropically etching the emitter exposing the base layer; forming a self-aligned dielectric sidewall spacer upon the emitter and base; self-alignedly depositing a self-aligned base electrode; using the self-aligned base electrode as a mask, anisotropically etching the base layer to expose the subcollector; and depositing a collector electrode on the subcollector layer.

Abstract: An interfacial oxide layer (185) is formed in the emitter regions of the NPN transistor (280, 220) and the PNP transistor (290, 200). Fluorine is selectively introduced into the polysilicon emitter region of the NPN transistor (220) to reduce the 1/f noise in the NPN transistor.

Abstract: In a semiconductor device acting as an HBT, an emitter/base laminate portion is provided on a Si epitaxially grown layer in the SiGeC-HBT. The emitter/base laminate portion includes a SiGeC spacer layer, a SiGeC core base layer containing the boron, a Si cap layer, and an emitter layer formed by introducing phosphorous into the Si cap layer. The C content of the SiGeC spacer layer is equal to or lower than that of the SiGeC core base layer.

Abstract: In a semiconductor device functioning as a SiGeC-HBT, an emitter/base stacked portion 20 is formed on a Si epitaxially grown layer 2. The emitter/base stacked portion 20 includes: a SiGeC spacer layer 21; a SiGeC core base layer 22 containing boron at a high concentration, a SiGe cap layer 23; a Si cap layer 24, and an emitter layer 25 formed by introducing phosphorus into the Si cap layer 24 and the SiGe cap layer 23.

Abstract: The invention includes an array of devices and a charge pump supported by a semiconductive material substrate. A damage region is under the array, and extends less than or equal to 50% of a distance between the array and the charge pump. The invention also includes a method in which a mask is formed over a monocrystalline silicon substrate. A neutral-conductivity-type dopant is implanted through an opening in the mask and into a section of the substrate to produce a damage region. A first boundary extends around the damage region. The masking layer is removed, and epitaxial silicon is formed over the substrate. An array of devices is formed to be supported by the epitaxial silicon. The array is bounded by a second boundary. The first boundary extends less than or equal to 100 microns beyond the second boundary.

Abstract: As the top electrode material of a thin-film electron emitter, a material having a bandgap wider than that of Si and electrical conductivity is used. In particular, a conductive oxide such as an SnO2 or ITO film and a wide-bandgap semiconductor such as GaN or SiC are employed. The electron energy loss in a top electrode through which hot electrons pass can be reduced so as to enhance the electron emission efficiency. A high emission current can be obtained in the case of the same diode current as a prior art. In addition, in the case of the same emission current density as a prior art, a small driving current is enough. A bus line and driving circuits can be simplified.

Abstract: A bipolar transistor has a high performance and high reliability, which are obtained by enhancing a withstanding voltage between an emitter and a base. The bipolar transistor includes a first impurity diffusion layer in a semiconducting substrate, an opening disposed in the first conductive film. A third impurity diffusion layer is formed so as to contain the second diffusion layer and side walls are formed on the side walls of the opening. A fourth impurity diffusion layer in the third impurity diffusion layer is formed in the opening surrounded by the side walls.

Abstract: According to a disclosed embodiment, a gas is supplied at a certain partial pressure for a chemical reaction with a top surface of a base in a transistor. The top surface of the base is heated to a certain temperature to promote the chemical reaction. For example, the gas can be oxygen, the base can be an epitaxial single crystal silicon-germanium base of a heterojunction bipolar transistor (“HBT”), and the chemical reaction can be oxidation of the silicon in the top surface of the silicon-germanium base. In one embodiment of the invention, the partial pressure of oxygen is maintained at 0.1 atmosphere and the top surface of the base is heated using rapid thermal processing (“RTP”) to a temperature of 500° C. The chemical reaction forms a dielectric layer on the top surface of the base. For example, using oxygen as stated above, a dielectric layer of silicon oxide (“interfacial oxide”) is formed.

Abstract: The present invention relates to a bipolar transistor of NPN type implemented in an epitaxial layer within a window defined in a thick oxide layer, including an opening formed substantially at the center of the window, this opening penetrating into the epitaxial layer down to a depth of at least the order of magnitude of the thick oxide layer, an N-type doped region at the bottom of the opening, a first P-type doped region at the bottom of the opening, a second lightly-doped P-type region on the sides of the opening, and a third highly-doped P-type region in the vicinity of the upper part of the opening, the three P-type regions being contiguous and forming the base of the transistor.

Abstract: According to one exemplary embodiment, a heterojunction bipolar transistor comprises a base having a top surface. The heterojunction bipolar transistor further comprises a first spacer and a second spacer situated on the top surface of the base. The heterojunction bipolar transistor further comprises an intermediate oxide layer situated on the first and second oxide spacers. The heterojunction bipolar transistor further comprises an amorphous layer situated on the intermediate oxide layer. The heterojunction bipolar transistor further comprises an antireflective coating layer on the amorphous layer. The heterojunction bipolar transistor further comprises an emitter window opening situated between the first and second spacers, where the emitter window opening is defined by the top surface of the base, the first and second spacers, the intermediate oxide layer, the amorphous layer, and the antireflective coating layer.

Abstract: A semiconductor device having a bipolar transistor which is capable of high integration, and a semiconductor device in which the bipolar transistor has good characteristic properties. A process for producing said semiconductor device.

Abstract: A first dopant impurity producing a conductivity type for formation of an intrinsic base diffusion layer and a dopant impurity producing the opposite conductivity type are implanted into a semiconductor substrate. An exposed surface of the semiconductor substrate is irradiated with a plasma, so that many crystalline defects are produced. Next, a polysilicon film is formed under conditions that cause the grain size to increase. In a portion of the polysilicon film located near the exposed surface of the semiconductor substrate, the grain size becomes relatively small, influenced by the crystalline defects in the substrate surface. In a portion of the polysilicon film located on the silicon oxide film, the grain size becomes relatively large, uninfluenced by the crystalline defects. Thus, degradation of electrical characteristics is suppressed, and variation in resistance of the resistance element is alleviated.

Abstract: An n-type low impurity concentration semiconductor layer is provided, by epitaxial growth or the like, on a p-type semiconductor substrate. In order to vertically form a semiconductor device in the low impurity concentration semiconductor layer, at least a p-type diffusion region is provided. In a surface of the semiconductor layer, a collector electrode and a base electrode are respectively formed in electrical connection to the n-type low impurity concentration semiconductor layer and the p-type diffusion region. The collector electrode is formed on a surface of the n+-type low resistance region of a polycrystal semiconductor formed depthwise in the low impurity concentration semiconductor layer.

Abstract: An object of the invention is to minimize variation in characteristics of a vertical bipolar transistor. An insulating side wall spacer composed of a silicon nitride film 10 and a silicon oxide film 9 is formed on the side surface of an opening 101 formed in a base electrode polysilicon film 7. The thickness (=WD) of the insulating side wall spacer is made thicker than the maximum thickness (=WF) within a range of variation in thickness of a polycrystalline film 12 grown from the side surface of the base electrode polysilicon film 7 exposed inside the opening 101 (namely, WD>WF). The size of an opening for forming an emitter electrode polysilicon film 16 on an intrinsic base 11 is not influenced by the thickness of a polycrystalline film 12 epitaxially growing from the side surface of the polysilicon film 7 for the base electrode, but is defined by the side wall spacer formed on a portion of the side surface of the base electrode polysilicon film.

Abstract: A laser apparatus and methods are disclosed for synthesizing areas of wide-bandgap semi-conductor substrates or thin films, including wide-bandgap semiconductors such as silicon carbide, aluminum nitride, gallium nitride and diamond to produce electronic devices and circuits such as integral electronic circuit and components thereof.

Abstract: The invention relates to a process for making a lateral PNP bipolar electronic device integrated monolithically on a semiconductor substrate together with other bipolar devices of the NPN type, said device being incorporated to an electrically insulated multilayer structure. The device includes a semiconductor substrate doped with impurities of the P type; a first buried layer doped with impurities of the N type to form a base region; and a second layer, overlying the first and having conductivity of the N type, to form an active area with opposite collector and emitter regions being formed in said active area and separated by a base channel region. The width of the base channel region is defined essentially by a contact opening formed above an oxide layer deposited over the base channel region. Advantageously, the contact opening is formed by shifting an emitter mask.

Abstract: A lateral bipolar transistor includes: a substrate; a first insulative region formed on the substrate; a first semiconductor region of a first conductivity type selectively formed on the first insulative region; a second insulative region formed so as to substantially cover the first semiconductor region; and a second semiconductor region of a second conductivity type different from the first conductivity type, a second semiconductor region being selectively formed, wherein: the second insulative region has a first opening which reaches a surface of the first semiconductor region, and the first semiconductor region has a second opening which reaches the underlying first insulative region, the second opening being provided in a position corresponding to the first opening of the second insulative region; the second semiconductor region is formed so as to fill the first opening and the second opening, thereby functioning as a base region; a lower portion of the second semiconductor region which at least fills th

Abstract: In the manufacture of integrated semiconductor structures, the problem frequently occurs that the resistance of polysilicon structures employed as interconnects must be selectively lowered. In order to reduce the resistance of a polysilicon structure, the structure is often provided with a silicide layer. However, the manufacturing problem occurs when siliconizing only specific polysilicon structures but not siliconizing others, for example those that are to be employed for resistors.

Abstract: An n-type low impurity concentration semiconductor layer is provided, by epitaxial growth or the like, on a p-type semiconductor substrate. In order to vertically form a semiconductor device in the low impurity concentration semiconductor layer, at least a p-type diffusion region is provided. In a surface of the semiconductor layer, a collector electrode and a base electrode are respectively formed in electrical connection to the n-type low impurity concentration semiconductor layer and the p-type diffusion region. The collector electrode is formed on a surface of the n+-type low resistance region of a polycrystal semiconductor formed depthwise in the low impurity concentration semiconductor layer.

Abstract: A lateral bipolar transistor for an intergrated circuit is provided that maintains a high current gain and high frequency capability without sacrificing high Early voltage. More particularly, a lateral bipolar transistor is formed on an integrated circuit having both bipolar and CMOS devices, the lateral bipolar transistor being formed according to the BiCMOS method and without additional steps relative to formation of vertical bipolar devices if provided in the same area. Among other things, an integrated circuit is provided in which P well structures are provided in the collector regions of an LPNP that have been found to affect a significant increase in the product of the Early voltage and the current gain.

Abstract: A bipolar transistor is provided which is of high reliability and high gain, and which is particularly suitable to high speed operation. The bipolar transistor operates with high accuracy and with no substantial change of collector current even upon change of collector voltage. It also has less variation than conventional bipolar transistors for the collector current while ensuring high speed properties and high gain. In one example, the band gap in the base region is smaller than the band gap in the emitter and collector regions. The band gap is constant near the junction with the emitter region and decreases toward the junction with the collector region. A single crystal silicon/germanium is a typically used for the base region.

Abstract: A bipolar transistor comprises a base region and an an extrinsic base region being located generally adjacent to the base region. The extrinsic base region has implanted therein a dopant and a dopant diffusion-retarding substance. The dopant diffusion-retarding substance serves to reduce the diffusion of the dopant into the base region. Preferably, the dopant and diffusion-retarding substances are implanted such that there is a buffer zone in the extrinsic base region immediately adjacent to the base region into which the dopant may diffuse after implantation. The dopant may for example be boron, and the dopant diffusion-retarding substance may for example be a group IV element such as carbon or germanium.

Abstract: A method of fabricating a bipolar transistor structure is provided in which a blanket silicon-germanium (SiGe) film is used in a self-aligned manner to form the active base region of the bipolar device, thereby eliminating the need for a complicated selective SiGe process.

Abstract: A guard ring structure formed around the periphery of a bipolar semiconductor device. A guard region (11) is formed in a substrate (1) of the device so as to extend adjacent a peripheral portion of the device. An insulating layer (3) is formed on the substrate between the peripheral portion of the device and the guard region (11). A polysilicon layer (13) is formed on the insulating layer (3) and covered with a layer of densified dielectic (14). Electrical interconnections are provided between the polysilicon layer (13) and the guard region (11) at spaced apart portions of the device where the guard structure does not need to be protected by the densified dielectric.

Abstract: A first insulating film 4 having a first opening portion is formed on an emitter region 10 and a second insulating film 6 having a second opening portion smaller than the first opening portion is formed on the first insulating film 4. The first and second opening portions are buried with emitter electrode material 9 doped with impurities.

Abstract: The present invention provides a method of manufacturing a bipolar transistor. The method includes producing an opening in a dielectric layer located over a substrate and forming a collector in the substrate by implanting a first dopant through the opening. The method further includes creating an intrinsic base region contacting the collector and constructing an emitter contacting the intrinsic base region, both of which are through the opening.

Abstract: A bipolar transistor structure that includes a semiconductor material substrate that has a bottom substrate and base region of a first conductivity type and a buried layer, collector region and sink region of a second conductivity type. The substrate has an extrinsic base region of the first conductivity type and an emitter region of the second conductivity type, both of which extend from the substrate's upper surface into the base region. The bipolar transistor structure also includes a single patterned polysilicon layer with a first polysilicon portion of the first conductivity type in contact with the extrinsic base region and a second polysilicon portion of the second conductivity type in contact with the emitter region. The bipolar transistor structure is compact since contact to the extrinsic base region is made by the first polysilicon portion, which can be formed to a minimum dimension and self-aligned to the extrinsic base region.

Abstract: A method has been provided for forming a polycrystalline silicon (p-Si) film with a small amount of hydrogen. Such a film has been found to have excellent sheet resistance, and it is useful in the fabrication of liquid crystal display (LCD) panels made from thin film transistors (TFTs). The low hydrogen content polycrystalline silicon films are made from introducing a small amount of hydrogen gas, with Ar, during the sputter deposition of an amorphous silicon film. The hydrogen content in the film is regulated by controlling the deposition temperatures and the volume of hydrogen in the gas feed during the sputter deposition. The polycrystalline silicon film results from annealing the low hydrogen content amorphous silicon film thus formed.

Abstract: A bipolar transistor according to the invention is provided with structure that an intrinsic base made of single crystal Si—Ge and a base leading-out electrode are connected via a link base made of polycrystal Si—Ge by doping at high concentration, further, a part immediately under the intrinsic base has the same conductive type as that of a collector and in a peripheral part, a single crystal Si—Ge layer having the same conductive type as that of a base is provided between the intrinsic base and a collector layer. Hereby, the reduction of the resistance of the link base between the intrinsic base and the base leading-out electrode and the reduction of capacitance between the collector and the base are simultaneously realized, and a self-aligned bipolar transistor wherein capacitance between an emitter and the base and capacitance between the collector and the base are respectively small, power consumption is small and high speed operation is enabled is acquired.

Abstract: Provided is a BiCOMOS semiconductor integrated circuit device which comprises a semiconductor substrate having an insulating layer internally and partially embedded therein and a semiconductor layer deposited on the insulating layer, an insulated gate type transistor formed in the semiconductor layer, a highly-doped collector layer of a bipolar transistor embedded in an insulating-layer-free portion of the semiconductor substrate, and a low-doped collector layer disposed on the highly-doped collector layer of the bipolar transistor, wherein the height level of the lower portion of the low-doped collector layer is below the height level of the lower portion of the insulating layer so as to attain high breakdown voltage and high speed operation of the bipolar transistor.

Abstract: A semiconductor bipolar transistor structure having improved electrostatic discharge (ESD) robustness is provided as well as a method of fabricating the same. Specifically, the inventive semiconductor structure a semiconductor structure comprises a bipolar transistor comprising a lightly doped intrinsic base; a heavily doped extrinsic base adjacent to said intrinsic base, a heavily doped/lightly doped base doping transition edge therebetween, said heavily doped/lightly doped base doping transition edge defined by an edge of a window; and a silicide region extending on said extrinsic base, wherein said silicide region is completely outside said window.

Abstract: A semiconductor device including a bipolar transistor formed by epitaxial growth or ion implantation is provided has an epitaxial silicon collector layer, a base region directly under an emitter defined as an intrinsic base and a peripheral region thereof defined as an outer base region is formed by the step of implanting ions into the collector layer to form a high concentration collector region at a location close to a buried region using a photoresist to form an aperture, and the step of implanting ions into the collector layer to form a high concentration collector region directly beneath the base region after forming the base region.

Abstract: The breakdown voltage of a semiconductor device, such as a transistor fabricated in a device region in and abutting the surface of a semiconductor body with a field oxide surrounding the device region, is improved by etching the field oxide abutting the device region to reduce the thickness thereof to about 0.6-1.4 &mgr;m and then forming a field plate in the recessed field oxide which is capacitively coupled to the underlying semiconductor body. The field plate can be floating, connected to a voltage potential, or connected to the semiconductor device.

Abstract: Lateral bipolar transistor, in which a thin diffusion barrier (4) is applied to a base region (10) between an emitter region (9) and a collector region (11), and there is present, on said barrier, a base electrode (8) which is provided for low-resistance supply, is connected to a heavily doped base terminal region and consists of polysilicon, for example, into which dopant is diffused out from said base terminal region.

Abstract: A semiconductor device, such as a BiCMOS, includes a bipolar transistor having at least an emitter region. An emitter electrode is formed on the emitter region. Further, a wiring pattern is formed over the emitter region. A plurality of contact plugs are formed to electrically connect the emitter electrode with the wiring pattern. The contact plugs are partially embedded in the emitter electrode in order to prevent of reduction of the current amplification factor of the bipolar transistor.

Abstract: This invention includes a semiconductor substrate of one conductivity type having a semiconductor layer of an opposite conductivity type from an upper surface to a predetermined depth and first and second projections on the semiconductor layer of the opposite conductivity type, a first insulating film formed on an upper surface of the semiconductor substrate of one conductivity type from a portion except for the first and second projections to a predetermined level not reaching upper surfaces of the first and second projections, a semiconductor film of one conductivity type formed on at least the upper surface of the first projection, a first semiconductor film of the opposite conductivity type formed on at least the upper surface of the second projection, and a second semiconductor film of the opposite conductivity type formed in a predetermined position on an upper surface of the semiconductor film of one conductivity type. This structure allows an emitter to be formed without any alignment.

Abstract: The invention relates to semiconductor devices having a bipolar transistor to form an isolation area within a base electrode contact area to ensure stable contact of the base electrode. The bipolar transistor formed in the transistor area is in the form of an island and is rectangular when view from above. The isolation area is formed of a dielectric material around the transistor area, and the base area is formed around the emitter area which forms the central area of the transistor area. A contact groove is formed at the inner interface of the isolation groove which faces the outer surface of the transistor area, and a part of the base electrode is buried in the contact groove and faces at least one of the upper surface of the transistor area and an inner surface of the contact groove.

Abstract: An n-type first single crystal silicon layer is provided as collector region over a silicon substrate with a first insulating film interposed therebetween. A p-type first polysilicon layer is provided as an extension of a base region over the first single crystal silicon layer with a second insulating film interposed therebetween. A p-type second single crystal silicon layer is provided as intrinsic base region on a side of the first single crystal silicon layer, second insulating film and first polysilicon layer. An n-type third single crystal silicon layer is provided as emitter region on a side of the second single crystal silicon layer. And an n-type third polysilicon layer is provided on the first insulating film as extension of an emitter region and is connected to a side of the third single crystal silicon layer.

Abstract: The vertical bipolar transistor includes an SiGe heterojunction base formed by a stack of layers of silicon and silicon-germanium resting on an initial layer of silicon nitride extending over a side insulation region surrounding the upper part of the intrinsic collector. The stack of layers also extends on the surface of the intrinsic collector which lies inside a window formed in the initial layer of silicon nitride.

Abstract: Laser apparatus and methods are provided for synthesizing areas of ceramic substrates or thin films, such ceramics as Silicon Carbide and Aluminum Nitride, to produce electronic devices and circuits such as sensors as integral electro circuit components thereof. Circuit components such as conductive tabs, interconnects, wiring patterns, resistors, capacitors, insulating layers and semiconductors synthesized on the surfaces and within the body of such ceramics. Selected groupings and arrangements of these electronic circuit components within the substrates or thin films provide a wide range of circuits for applications such as digital logic elements and circuits, transistors, sensors for measurements and monitoring effects of chemical and/or physical reactions and interactions of materials, gases, devices or circuits that may utilize sensors.

Abstract: A method for making self-aligned sub-micrometer bipolar transistors and FETs on a substrate for BiFET and BiCMOS circuits was achieved using a novel LOCOS structure as a self-aligned implant mask. This LOCOS structure uses a silicon nitride mask comprised of stripes with well defined widths and spacings to form a punchthrough oxide mask of varying thicknesses over the emitter, base, and collector of the bipolar transistor, while providing a thick field oxide elsewhere on the substrate. The oxide mask serves as a self-aligned implant mask for implanting the emitter, base, and collector of the bipolar transistor. The nitride mask can be patterned concurrently to form an implant mask for the FET. A series of ion implants is then used to form the emitter, base, and collector without requiring separate photoresist masks. An array of nitride stripes with well defined widths and spacings can be used to make larger transistors, such as bipolar power transistors.

Abstract: Methods of forming bipolar junction transistors having preferred base electrode extensions include the steps of forming a base electrode of second conductivity type (e.g., P-type) on a face of a substrate. A conductive base electrode extension layer is then formed in contact with a sidewall of the base electrode. The base electrode extension layer may be doped or undoped. An electrically insulating base electrode spacer is then formed on the conductive base electrode extension layer, opposite the sidewall of the base electrode. The conductive base electrode extension layer is then etched to define a L-shaped base electrode extension, using the base electrode spacer as an etching mask. Dopants of second conductivity type are then diffused from the base electrode, through the base electrode extension and into the substrate to define an extrinsic base region therein.

Abstract: A method and lateral bipolar transistor structure are achieved, with high current gain, compatible with CMOS processing to form BiCMOS circuits. Making a lateral PNP bipolar involves forming an N− well in a P− doped silicon substrate. A patterned Si3N4 layer is used as an oxidation barrier mask to form field oxide isolation around device areas by the LOCOS method. A polysilicon layer over device areas is patterned to leave portions over the intrinsic base areas of the L-PNP bipolar an implant block-out mask. A buried N− base region is implanted in the substrate under the emitter region. A photoresist mask and the patterned polysilicon layer are used to implant the P++ doped emitter and collector for the L-PNP. The emitter junction depth xj intersects the highly doped N+ buried base region. This N+ doped base under the emitter reduces the current gain of the unwanted (parasitic) vertical PNP portion of the L-PNP bipolar to reduce the current gain of the V-PNP.

Abstract: A process for fabricating a bipolar transistor on a silicon-on-insulator substrate which includes etching a bipolar transistor area into the substrate, wherein the bipolar transistor area has substantially vertical sidewalls and a bottom, and forming a buried collector in bottom of the bipolar transistor area. Polysilicon sidewalls are formed adjacent to the vertical sidewalls in the bipolar transistor area, wherein the polysilicon sidewalls are connected to the buried collector. The polysilicon sidewalls are oxidized to form a layer of oxidized polysilicon. Oxide sidewalls are formed on the oxidized polysilicon sidewalls, and epitaxial silicon is formed to fill the bipolar transistor area. A base and an emitter are formed for the bipolar transistor, within the epitaxial barrier.

Abstract: A bipolar transistor and a method of fabricating the same are provided which are adapted to reduce chip size and production costs. To produce the transistor, a second conductive type well region is formed in a first conductive type semiconductor substrate and isolation trenches are formed at both sides of the well region. A high density second conductive type buried layer is formed in the semiconductor substrate which is formed at the bottom of the isolation trench. The buried layer is formed in two regions surrounding respective bottoms of two adjacent isolation trenches. The two regions are electrically connected with each other and in direct contact with the well region. An extrinsic base region and a device isolation region are formed sequentially onto the semiconductor substrate using a nitration layer pattern as a mask, wherein the nitration layer pattern is formed on the surface of semiconductor substrate.