Abstract: An arrangement in a semiconductor component includes a highly doped layer on a substrate layer and is delimited by at least one trench extending from the surface of the component through the highly doped layer. A sub-layer between the substrate layer and the highly doped layer is doped with the same type of dopant as the buried collector, but to a lower concentration. The sub-layer causes a more even distribution of the potential lines in the substrate and in a sub-collector layer, thereby eliminating areas of dense potential lines and increasing the breakdown voltage of the component, (i.e., because the breakdown voltage is lower in areas with dense potential lines).

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: 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: A resin-molded unit (1) includes a semiconductor bear chip (2) arranged inside and sealed in an epoxy resin mold (3). The resin-molded unit is entirely covered with a magnetic loss film (5) as a high-frequency current suppressor. It is preferable that the magnetic loss film is made of a granular magnetic material. A plurality of lead frames (4) may be extended from the semiconductor bear chip to the outside through the epoxy resin mold.

Abstract: A heterojunction bipolar transistor is fabricated by stacking a Si collector layer, a SiGeC base layer and a Si emitter layer in this order. By making the amount of a lattice strain in the SiGeC base layer on the Si collector layer 1.0% or less, the band gap can be narrower than the band gap of the conventional practical SiGe (the Ge content is about 10%), and good crystalline can be maintained after a heat treatment. As a result, a narrow band gap base with no practical inconvenience can be realized.

Abstract: A heterojunction bipolar transistor is fabricated by stacking a Si collector layer, a SiGeC base layer and a Si emitter layer in this order. By making the amount of a lattice strain in the SiGeC base layer on the Si collector layer 1.0% or less, the band gap can be narrower than the band gap of the conventional practical SiGe (the Ge content is about 10%), and good crystalline can be maintained after a heat treatment. As a result, a narrow band gap base with no practical inconvenience can be realized.

Abstract: SUMMARY

Abstract: A photocell includes an emitter having a ratio of salicided area to non-salicided area. The ratio determines the gain of the photocell and lowers fixed pattern noise.

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 bipolar transistor has a lightly doped n-type single crystal silicon layer epitaxially grown in a recess formed in a heavily doped n-type impurity region after a selective growth of a thick field oxide layer, a base region, an emitter region and a collector contact region are formed in surface portions of the lightly doped n-type single crystal silicon layer, and the single crystal silicon layer is not affected by the heat during the growth of the thick field oxide layer, and has a flat zone constant in dopant concentration regardless of the thickness thereof.

Abstract: An object of the present invention is to provide a lateral bipolar transistor having a high current driving capacity and a high current amplification factor as well as a high cut-off frequency. A device area 13 surrounded by an isolating insulation layer is formed on the surface of a semiconductor substrate 11. A base area 15 is formed in the device area 13 to a specified depth from the surface of the semiconductor substrate 11. A core insulation layer 25 is formed in the base area 15 with a depth shallower than the base area 15 from the surface of the semiconductor substrate 11. Around the core insulation layer 25, there are formed emitter areas 26. A collector area 17 is formed at a specified distance from the emitter area 26. Since the bottom area of the emitter area 26 is reduced by being provided with the core insulation layer 25 without reducing the side area of the emitter area 26, the current driving capacity and the current amplification factor of the transistor are thus improved.

Abstract: The invention relates to a semiconductor device comprising a bipolar transistor having a collector (1), a base (2) and an emitter (3) at its active area (A). The semiconductor body (10) of the device is covered with an insulating layer (20). At least a part of a base connection conductor (5) and an emitter connection conductor (6) extend over the insulating layer (20) and lead to a base connection area (8) and an emitter connection area (9), respectively. The known transistor is characterized by poor gain, particularly at high frequencies and at high power.

Abstract: To provide a semiconductor device that has a positive ON-voltage temperature coefficient and a high switching speed at the current densities provided during actual operation. A (p) anode layer 1 is formed on one surface of an (n) base layer 3 having high resistance, and an (n) cathode layer 2 is formed on the other surface. The surface of the (p) anode layer 1 is coated with an insulating film having contact slots formed therein, and the anode electrode 5 is formed on the (p) anode layer 1 and is fixed to the (p) anode layer 1 at the locations of the contact slots 7. A cathode electrode 6 is formed on the (n) cathode layer 2. In addition, the planar pattern of the contact slots 7 is shaped like stripes. The area ratio S1/S2 is 5 or more and 30 or less, where area S1 constitutes the (p) anode layer 1 that is occupied by an insulating film 4 (the area of a non-secured portion), and area S2 represents the locations of the contact slots 7 (the area of the secured portion).

Abstract: A bipolar transistor compatible with CMOS processes utilizes only a single layer of polysilicon while maintaining the low base resistance associated with conventional double-polysilicon bipolar designs. Dopant is implanted to form the intrinsic base through the same dielectric window in which the polysilicon emitter contact component is later created. Following poly deposition within the window and etch to create the polysilicon emitter contact component, large-angle tilt ion implantation is employed to form a link base between the intrinsic base and a subsequently-formed base contact region. Tilted implantation enables the link base region to extend underneath the edges of the polysilicon emitter contact component, creating a low resistance path between the intrinsic base and the extrinsic base. Fabrication of the device is much simplified over a conventional double-poly transistor, particularly if tilted implantation is already employed in the process flow to form an associated structure such as an LDMOS.

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: An emitter contact structure, and associated method, for a bipolar junction transistor. The emitter contact structure includes a collector region, an intrinsic base region within the collector region, an extrinsic base region within the collector region, a base link-up region within the collector region between the intrinsic base region and the extrinsic base region, a base link diffusion source layer above the base link-up region, a capping layer above the base link diffusion source layer, and a base electrode laterally engaging the extrinsic base region.

Abstract: A bipolar power transistor intended for radio frequency applications, especially for use in an amplifier stage in a radio base station, and a method for manufacturing the bipolar power transistor are provided. The power transistor includes a substrate (13), an epitaxial collector layer (15) on the substrate (13), a base (19) and an emitter (21) formed in the collector layer (15). The degree of doping Nc(x) of the collector layer varies from its upper surface (24) and downwards to at least half the depth of the collector layer, essentially according to a polynom of at least the second degree, a0+a1x+a2x2+ . . . , where a0 is the degree of doping at the upper surface (24), x is the vertical distance from the same surface (24) and a1, a2, . . . are constants. The transistor can further include an at least approximately 2&mgr; thick insulation oxide (17) between the epitaxial collector layer (15) and higher situated metallic connections layers (31, 33).

Abstract: A substantially concentric lateral bipolar transistor and the method of forming same. A base region is disposed about a periphery of an emitter region, and a collector region is disposed about a periphery of the base region to form the concentric lateral bipolar transistor of the invention. A gate overlies the substrate and at least a portion of the base region. At least one electrical contact is formed connecting the base and the gate, although a plurality of contacts may be formed. A further bipolar transistor is formed according to the following method of the invention. A base region is formed in a substrate and a gate region is formed overlying at least a portion of the base region. Emitter and collector terminals are formed on opposed sides of the base region. The gage is used as a mask during first and second ion implants.

Abstract: An integrated device in an emitter-switching configuration comprises a first bipolar transistor having a base region, an emitter region, and a collector region, a second transistor having a charge-collection terminal connected to an emitter terminal of the first transistor, and a quenching element having a terminal connected to a base terminal of the first transistor. The quenching element is formed within the base region or the emitter region of the first transistor.

Abstract: On an n-type semiconductor substrate 41 doped in high density, a p-type semiconductor layer 2, an n-type semiconductor layer 4 doped in high density, which is a collector, a p-type semiconductor layer 6 doped in high density, which is a base, and the n-type semiconductor layer 7, which is an emitter, are sequentially stacked. To the collector layer, a collector electrode 12 is electrically connected, and to the base layer, a base electrode 11 is electrically connected, and to the emitter layer, an emitter electrode 9 is electrically connected, and thus a bipolar transistor is structured. On the bipolar transistor, an insulated isolation area 55 is formed with an opening therein, whose depth reaches the surface of the substrate, and a substrate electrode 48 is formed thereon. On the bipolar transistor and the insulated isolation area 55, an inter-layer dielectric layer 54 is formed having contact holes formed to upper parts of the emitter electrode 49 and to the substrate electrode 48.

Abstract: An epitaxial layer is formed on a main surface of a high specific resistance silicon substrate having a specific resistance of at least 100 .OMEGA.cm. A circuit element such as an active element is formed in epitaxial layer. An oxide film is formed such that it covers a surface of epitaxial layer. A metal interconnection layer is formed on a surface of oxide film. An oxide film is formed such that it covers metal interconnection layer. Thus, an inexpensive HF circuit device capable of reducing transmission loss of HF signals can be obtained.

Abstract: A vertical PNP transistor integrated in a semiconductor material wafer having an N type substrate and an N type epitaxial layer forming a surface. The transistor has a P type buried collector region astride the substrate and the epitaxial layer; a collector sinker insulating an epitaxial tub from the rest of the wafer; a gain-modulating N type buried base region astride the buried collector region and the epitaxial tub, and forming a base region with the epitaxial tub; and a P type emitter region in the epitaxial tub. An N.sup.+ type base sinker extends from the surface, through the epitaxial tub to the buried base region. The gain of the transistor may be modulated by varying the extension and dope concentration of the buried base region, forming a constant or variable dope concentration profile of the buried base region, providing or not a base sinker, and varying the form and distance of the base sinker from the emitter region.

Abstract: In order to prevent an epitaxial layer from contamination by metal when the epitaxial layer is formed on a substrate on which a conductor film comprising a metallic film is formed, a bipolar transistor (semiconductor device) 1 has the first conductor pattern 8 comprising a high-melting metallic film or a high-melting metallic compound film formed on the substrate 4, and the second conductor pattern 9 comprising a non-metallic film formed so as to cover the first conductor pattern 8. On the substrate 4 is formed the first conductivity type base layer 10 on the semiconductor layer comprising an epitaxial layer so as to come in contact with the second conductor pattern 9. Furthermore, when manufacturing the bipolar transistor 1, the semiconductor layer as the base layer 10 is formed with the epitaxial process after the first conductor pattern 8 is covered by the second conductor pattern 9.

Abstract: A bipolar transistor formed on a SOI substrate has a buried collector layer underlying an emitter region and a collector contact region for connection thereof, both of which are made of a doped polysilicon film deposited in a removed portion of an oxide film etched by wet etching and a collector contact groove, respectively. By reducing the area of the buried collector layer, the bipolar transistor has excellent frequency characteristics in a high-frequency range.

Abstract: A semiconductor device with a bipolar transistor that decreases the parasitic capacitance between a base connection layer and a collector region is provided. This device is comprised of a semiconductor substrate having a main surface, a collector region formed in the substrate, a base region formed in the substrate, an emitter region formed in the substrate, a first dielectric layer formed on the main surface of the substrate to be overlapped with the collector region, a conductive layer formed on the first dielectric layer and applied with a specific electric potential, a second dielectric layer formed to cover the conductive layer, a base connection layer formed on the second dielectric layer and electrically connected to the base region, and a base electrode electrically connected to the base connection layer. The emitter region, the base region, and the collector region constitute a bipolar transistor.

Abstract: The present invention provides a microwave integrated circuit device in which a sufficiently large gain can be obtained even in a high-frequency region by effectively reducing a ground inductance of a transistor. The device includes both a semiconductor substrate on which a bipolar transistor is formed and a microstrip line formed on the semiconductor substrate. The microstrip line is constituted of a grounded conductive layer, which is electrically connected to both ends of a base electrode, and input and output signal lines connected to emitter and collector electrodes of the transistor, respectively.

Abstract: Method and apparatus for improving the high current operation of bipolar transistors while minimizing adverse affects on high frequency response are disclosed. A local implant to increase the doping of the collector at the collector to base interface is achieved by the use of an angled ion implant of collector impurities through the emitter opening. The resulting area of increased collector doping is larger than the emitter opening, which minimizes carrier injection from the emitter to the collector, but is smaller than the area of the base.

Abstract: A bipolar silicon transistor includes at least one emitter zone with n.sup.+ arsenic doping and with a phosphorus doping. The ratio between arsenic dopant concentration and phosphorus dopant concentration is between 10:1 and 500:1 in the at least one emitter zone. The at least one emitter zone may also have a penetration depth of less than 0.5 .mu.m. A method for producing a bipolar silicon transistor includes implanting a n.sup.+ -doped emitter zone with arsenic, implanting the n.sup.+ -doped emitter zone with phosphorus, setting a ratio in the n.sup.+ -doped emitter zone between the arsenic dopant concentration and phosphorus dopant concentration to between 10:1 and 500:1, and annealing crystal defects.

Abstract: A high frequency bipolar transistor (30, 60) having reduced capacitance and inductance is formed over a substrate (61). The substrate (61) is heavily doped to form a low resistance current path. A lightly doped epitaxial layer (62) isolates the substrate (61) from layers which form the transistor. The epitaxial layer (62) is the same conductivity type as the substrate (61). A topside substrate contact (73) couples an emitter of the transistor (60) to the substrate (61). The backside of the substrate (61) is metalized and conductively attached to a leaded flag of a leadframe (51) thereby eliminating wirebond inductance in the emitter of the transistor.

Abstract: A bipolar transistor includes an emitter, a base, a collector, an additional base semiconductor region having the same conductivity type as the base, arranged at the emitter and constituting a connection with the emitter. A first electrical connection connects the additional base semiconductor region with the base, thereby short-circuiting the additional base semiconductor region relative to the base, such that the additional base semiconductor region and base together constitute a combined base of the transistor. A further semiconducting collector region has the same conductivity type as the collector. A second electrical connection connects the further semiconductor connecting region and the collector, thereby short-circuiting the further semiconducting collector region and the collector, such that the additional semiconducting collector region and the collector together constitute a combined collector of the transistor.

Abstract: A semiconductor circuit includes a semiconductor layer having a surface and a monolithic output stage formed in the semiconductor layer. The monolithic output stage extends to the surface of the semiconductor layer and has a periphery within the semiconductor layer, an output terminal, and a supply terminal. A barrier well is formed in the semiconductor layer and adjacent to at least a portion of the periphery of the monolithic output stage. The barrier well extends to the surface of the semiconductor layer and has a first conductivity. A diode having first and second diode regions is disposed in the semiconductor layer. The first diode region is coupled to the supply terminal. The diode is operable to prevent current flow from the barrier well to the supply terminal when the voltage between the supply and output terminals has a first polarity.

Abstract: A method of producing a bipolar transistor includes the step of forming an emitter contact layer containing a high concentration of impurity by means of plasma doping or solid-state diffusion without causing diffusion of impurity in a base layer. This makes it possible to realize a thin base layer having a high impurity concentration.The invention also provides a method of producing a semiconductor device including a bipolar transistor and another device element such as a resistor element including a polysilicon layer containing an activated impurity in such a manner that both the bipolar transistor and the device element are disposed on the same single substrate, the method including the steps of: forming a polysilicon layer containing an activated impurity on the surface of a substrate; and then forming a base layer of the bipolar transistor. This method prevents the base layer from being affected by heat treatment on the polysilicon layer.

Abstract: It is an object to provide a semiconductor apparatus having improved dielectric breakdown strength characteristics both by eliminating the discontinuity caused to the interface between a semiconductor layer and the overlying insulator film on account of the FLR provided for increasing the dielectric breakdown strength and by preventing the redistribution of impurities from the FLR into the insulator film. Another object is to provide a process for fabricating such improved semiconductor apparatus. The semiconductor layers of a first conduction type (i.e., n.sup.- type semiconductor layer 1b and epitaxial layer 1c) are provided with the semiconductor region of a second conduction type (i.e., p-type base region 2) to form a semiconductor device (transistor) and FLRs 4a and 4b are provided external to the perimeter of said semiconductor region but without being exposed from the surface of the epitaxial layer 1c.

Abstract: A low-noise PNP transistor comprising a cutoff region laterally surrounding the emitter region in the surface portion of the transistor. The cutoff region has such a conductivity as to practically turn off the surface portion of the transistor, so that the transistor operates mainly in the bulk portion. The cutoff region is formed by an N.sup.+ -type enriched base region arranged between the emitter region and the collector region.

Abstract: A bipolar semiconductor integrated circuit has a pnp transistor through which a DC power is supplied from an external DC power to various elements of the bipolar IC and a constant current circuit for turning the pnp transistor on and regulating the base current of the pnp transistor to a constant level causing operation in the saturation range of the pnp transistor.

Abstract: A SiGe alloy film containing electrically active impurity in a concentration higher than the intrinsic base layer is formed on the eaves-structured polycrystalline silicon film for base electrode. After that, SiGe only just under the opening is removed completely by dry etching under a condition that etching speed of SiGe is faster than that of Si, and subsequently the intrinsic base layer is formed.

Abstract: A high performance, high voltage non-epi bipolar transistor including a substrate (12) with an n-type conductivity well (13) and an insulative layer (14) with first (15), second (17) and third (18) openings exposing the substrate in the well. A first p-type volume (19) surrounding the first and second openings (15, 17) beneath the insulative layer (14), and a second n-type volume (22) surrounding the third opening (18) beneath the insulative layer (14). A p-type intrinsic base (25) in the first opening (15) and in contact with the first volume (19). A p-type extrinsic base (30) in the second opening (17) and in contact with the first volume (19). An n-type collector (32) in the third opening (18) and in contact with the second volume (22), and an n-type emitter layer (27) in the first opening in overlying contact with the intrinsic base (25).

Abstract: A bipolar transistor, an nMOS transistor and pMOS transistor are formed at a main surface of a p-type semiconductor substrate. The bipolar transistor includes a collector layer, a base layer and an emitter layer. Collector layer located immediately under base layer contains impurity of n-type at a concentration not more than 5xl0.sup.18 cm.sup.-3. Base layer located immediately under emitter layer has a diffusion depth not more than 0.3 .mu.m. A semiconductor device including the bipolar transistor having the above structure is used in a circuit performing small amplitude operation. Thereby, it is possible to provide the semiconductor device having the bipolar transistor, which can be manufactured at a low cost and can operate at a high speed.

Abstract: Structure and fabrication details are disclosed for AlGaAs/GaAs microwave HBTs having improved thermal stability during high power operation. The use of a thermal shunt joining emitter contacts of a multi-emitter HBT is shown to improve this thermal stability and eliminate "current-crush" effects. A significant reduction in thermal resistance of the disclosed devices is also achieved by spreading the generated heat over a large substrate area using thermal lens techniques in the thermal shunt. These improvements achieve thermally stable operation of AlGaAs/GaAs HBTs up to their electronic limitations. A power density of 10 mW/.mu.m2 of emitter area is achieved with 0.6 W CW output power and 60% power-added efficiency at 10 GHz. The thermal stabilization technique is applicable to other bipolar transistors including silicon, germanium, and indium phosphide devices.

Abstract: A semiconductor device allowing reduction in collector resistance can be obtained without complicating manufacturing processes. In the semiconductor device, a first impurity layer of a first conductivity type having an impurity concentration higher than that of first semiconductor region is provided such that substantially all the upper portion thereof is in contact with a lower surface of a first element isolation insulating film which is formed between a base layer and a collector extraction layer As a result, the first impurity layer serves as a current path, reducing collector resistance. In addition, the first impurity layer can be easily formed by ion implantation, so that manufacturing processes will not be complicated.

Abstract: An N-type buried region formed in the surface area of a semiconductor substrate is electrically connected to an N-type collector region formed in an epitaxial silicon layer on the semiconductor substrate. A P-type buried region is formed to overlap part of the N-type buried region. The P-type buried region is thick in the upward and downward directions of the N-type buried region. One end portion of the P-type buried region is electrically connected to a P-type base region and the other end portion thereof is electrically connected to a base region formed in the surface area of the semiconductor layer. The base region is applied with a base potential from the base region via the buried region. An N-type emitter region is formed in the base region. The N-type buried region and the P-type buried region are simultaneously formed by use of a difference between the diffusion coefficients of impurity.

Abstract: Methods of forming bipolar junction transistors include the step of forming insulated gate electrode means adjacent the base region of the transistor so that the majority carrier conductivity of the base region and the gain (.beta.) of the transistor can be modulated in response to a gate bias. The methods can include the steps of forming an insulated gate electrode containing a conductive gate on a face of a substrate and then forming a base region in the substrate. These steps can then be followed by the steps of patterning the insulated gate electrode to define an opening which exposes a first portion of the base region at the face and then forming an emitter electrode in the opening. The emitter electrode and conductive gate are preferably formed to be in electrical contact so that during operation, the potential of the emitter electrode and conductive gate are maintained at the same level.

Abstract: A ring-shaped emitter region is formed either in a region a little toward an inner periphery or in a region a little toward an outer periphery in an upper layer portion of a ring-shaped base region of a bipolar transistor.A conductive layer is laminated through an insulating layer in a region surrounded by the ring-shaped emitter region provided a little toward the inner periphery of the base region, a conductive side wall is formed on the sides of the conductive layer and the insulating layer, and the ring-shaped emitter region and the conductive layer are connected through the conductive side wall. A metallic emitter electrode is connected to the conductive layer.

Abstract: A method of fabricating a semiconductor device includes producing a collector layer, a base layer, and an emitter layer on a semiconductor substrate; producing a dummy emitter electrode on a region of the emitter layer; forming a first resist except where the dummy emitter electrode is present; completely removing the dummy emitter electrode to expose the surface of the emitter layer; depositing an emitter electrode material on the first resist and the emitter layer that is exposed by the removal of the dummy emitter electrode; forming a mask on a region of the emitter electrode material film where an emitter electrode is later produced; and etching the emitter electrode material film using the mask; and removing the first resist, thereby producing an emitter electrode layer, a peripheral side part extending upward from the bottom part, and an upper fringe part protruding outward from the peripheral side part perpendicular to the peripheral side part.

Abstract: A self aligned lateral BJT is disclosed which has a lightly doped first region of a first conductivity type, e.g., P-type. A heavily doped poly region, of a second conductivity type, e.g., N-type, is provided on a portion of a surface of the first region. A heavily doped second region of the second conductivity type, is disposed in the first region below the poly region. An oxide region is provided on a portion of the first region surface adjacent to the poly region. A third region of the first conductivity type is disposed in the first region adjacent to the second region and below the oxide region. A heavily doped fourth region of the second conductivity type is disposed in the first region adjacent to the third region. The fabrication of the lateral BJT includes the step of forming a poly region on a portion of the first region. Then, the second region is formed by diffusing an impurity from the poly region into the first region. The third region is then formed adjacent to the second region.

Abstract: The present invention provides a bipolar transistor in which a lightly doped n-type hot-carrier shield extends in an epitaxial layer adjacent from a poly-emitter to an extrinsic base. This hot-carrier shield minimizes performance impairment that would otherwise occur due to a hot-carrier effect. Key steps in the method of making the bipolar transistor include a differential thermal oxidation while the poly-emitter is covered with a nitride cap. After the nitride cap is removed, an n-type dopant is implanted. The unprotected poly emitter is heavily doped. The implant partially penetrates a relatively thin oxide growth, thereby forming the hot-carrier shield. Other areas, such as the extrinsic base, and a polycrystalline base extension are covered by a relatively thick oxide growth and are unaffected by the n-type implant.

Abstract: A high voltage silicon rectifier includes a substrate portion and an epitaxial mesa portion that is a frustrum of a pyramid with a substantially square cross section and side walls that make a forty five degree angle with the substrate portion. The mesa portion includes three germanium doped layers that introduce strain to speed up recombination of charge carriers.

Abstract: The total base-collector capacitance of a double-heterostructure bipolar transistor device is reduced by removing semiconductor material from the extrinsic regions and replacing the removed material with a relatively-low-dielectric-constant material, The base-collector capacitance is further reduced by using a composite subcollector structure that permits the extrinsic regions to be made thicker than the intrinsic region of the device.

Abstract: A bipolar transistor having a control electrode area of a semiconductor of a first conductive type, and first and second main electrode areas positioned in contact with the control electrode area and composed of a semiconductor of a second conductive type different from the first conductive type, comprises, for the purpose of preventing depletion of the surface of the control electrode area and suppressing or annulating the current generated in the surfacial depletion area, an electrode for controlling the surface state of the control electrode area, positioned, across an insulation film, on the surface of the control electrode area including the vicinity of the junction between the control electrode area and the above-mentioned first main electrode area.

Abstract: A lateral transistor (14) is configured as a reverse protection diode that allows low and high current modes of operation while maintaining low forward voltage drop. The base region (38) of the lateral transistor is formed inside a collector ring (34) and adjacent to the emitter region (36). In low current mode, the transistor operates as a conventional diode. In high current mode, the excessive number of minority carriers injected into the base region causes the device to enter conductivity modulation that effectively increases the doping concentration and lowers the bulk resistance. The lower bulk resistance keeps the forward voltage drop low. By having the base region inside the collector ring, the bulk resistance is kept low to aid in the onset of conductivity modulation. Thus, the transition between low current mode and high current mode is minimized.