Abstract: A semiconductor device and a method of manufacturing the same is disclosed. A trench is formed in an active region of a semiconductor substrate. A doped layer is formed on the inner walls of the trench. The trench is filled up with a first semiconductor layer. A gate insulating layer is formed on the first semiconductor layer and the substrate. Two gate electrodes are formed on the gate insulating layer such that the trench is located in between two gate electrodes. First and second impurity regions are formed in the substrate on both sides of each of the gate electrodes. Since the doped layer is locally formed in the trench area, the source and drain regions are completely separated from the heavily doped layer to weaken the electric field of PN junction, thereby improving refresh and preventing punchthrough between the source and drain.

Abstract: A semiconductor device and a method of manufacturing the same is disclosed. A trench is formed in an active region of a semiconductor substrate. A doped layer is formed on the inner walls of the trench. The trench is filled up with a first semiconductor layer. A gate insulating layer is formed on the first semiconductor layer and the substrate. Two gate electrodes are formed on the gate insulating layer such that the trench is located in between two gate electrodes. First and second impurity regions are formed in the substrate on both sides of each of the gate electrodes. Since the doped layer is locally formed in the trench area, the source and drain regions are completely separated from the heavily doped layer to weaken the electric field of PN junction, thereby improving refresh and preventing punchthrough between the source and drain.

Abstract: A bipolar transistor in a monocrystalline semiconductor substrate (101), which has a first conductivity type and includes a surface layer (102) of the opposite conductivity type. The transistor comprises an emitter contact (110) on the surface layer; a base contact (130 and 131) extending through a substantial portion (141) of the surface layer, spaced apart (140a) from the emitter; an insulator region (150/151) buried under the base contact; a collector contact (120); and a first polycrystalline semiconductor region (152/153) selectively located under the insulator region, and a second polycrystalline semiconductor region (154) selectively located under the collector contact. These polycrystalline regions exhibit heavy dopant concentrations of the first conductivity type; consequently, they lower the collector resistance.

Abstract: A method of manufacturing a semiconductor device, including the steps of: forming first and second insulation films on a substrate; sequentially forming an organic sacrificing layer and first and second mask layers thereon; forming a wiring groove pattern in the second mask layer; forming a connection hole pattern for forming connection holes in the second and first mask layers and the organic sacrificing layer; forming a wiring groove pattern in the first mask layer and the organic sacrificing layer and forming the connection holes in the second insulation film, by etching conducted by use of the second and first mask layers as an etching mask; and forming the wiring grooves in the second insulation film and forming the connection holes in the second and first insulation films, by use of the first mask layer and the organic sacrificing layer as a mask.

Abstract: A sidewall-insulation film 9 is provided on a side surface of a first opening portion 8a formed in a base extraction electrode 5B of a hetero-junction bipolar transistor, and a portion of the sidewall-insulation film 9 extends so as to protrude from a surface opposite to a semiconductor substrate 1 toward a main surface of the semiconductor substrate 1 in the base extraction electrode 5B, and protruded length thereof is set to be equal to or smaller than one half of thickness of the insulation film 4 interposed between the main surface of the semiconductor substrate 1 and a lower surface of the base extraction electrode 5B.

Abstract: Bottom electrodes of memory cell capacitors are recessed to prevent electrical shorts between neighboring memory cells. A partially fabricated memory cell capacitor has a bottom electrode comprising titanium nitride (TiN) and hemispherical grained (HSG) silicon. The container housing the capacitor is filled with photoresist and then planarized. The TiN layer is then selectively recessed with a peroxide mixture and subsequently the HSG silicon layer is recessed using tetramethyl ammoniumhydroxide. Thus, the bottom electrode is recessed below the level of particles which may overlie the memory cell capacitors and cause shorts by contacting the bottom electrode.

Abstract: A semiconductor wafer is disclosed in which a high concentration impurity layer is formed in a semiconductor wafer to a predetermined depth, in order to electrically connect electrodes formed on the principal face of the wafer without forming trenches and through holes in the wafer. An n++ diffusion region is formed in the dicing region of a semiconductor wafer by ion implanting or diffusion. The diffusion region extends to an n++ layer formed deep in the semiconductor wafer. The width of the n++ diffusion region is made wide enough to account for the blade width of a dicer, so that an n++ diffusion region remains at the outer periphery of each of the chips divided by the dicing operation. Bump electrodes on the wafer surface electrically connect with the n++ layer deep in the semiconductor through the n++ diffusion region.

Abstract: According to one embodiment, a structure comprises a substrate and a field oxide region, where the field oxide region has a top surface, and where the top surface of the field oxide region comprises substantially no cavities caused by lateral etching. The structure further comprises a trench situated in the substrate, where the trench has a first sidewall and a second sidewall in the substrate, and where the trench is situated directly underneath the field oxide region. According to this embodiment, the trench is used as a deep trench isolation region in the substrate and is typically filled with polysilicon. A thermally grown oxide liner is situated on the first and the second sidewalls of the trench, where the oxide liner is formed after removal of a hard mask. The hard mask may be densified TEOS oxide or HDP oxide and may be removed in an anisotropic dry etch process.

Abstract: High reliable copper interconnects are formed with copper or a low resistivity copper alloy filling relatively narrow openings and partially filling relatively wider openings and a copper alloy having improved electromigration resistance selectively deposited in the relatively wider openings. The filled openings are recessed and a metal capping layer deposited followed by CMP. The metal capping layer prevents diffusion along the copper-capping layer interface while the copper alloy filling the relatively wider openings impedes electromigration along the grain boundaries.

Abstract: Semiconductor devices having improved isolation are provided along with methods of fabricating such semiconductor devices. The improved isolation includes an encapsulated spacer formed within a gate region of a device.

Abstract: A bipolar transistor, and manufacturing method therefor, with a substrate having a collector region and a base structure provided thereon. An emitter structure is formed over the base structure and an extrinsic base structure is formed over the base structure and over the collector region beside and spaced from the emitter structure. A dielectric layer is deposited over the substrate and connections are formed to the extrinsic base structure, the emitter structure and the collector region.

Abstract: A method of nitriding an insulation film, includes the steps of forming nitrogen radicals by high-frequency plasma, and causing nitridation in a surface of an insulation film containing therein oxygen, by supplying the nitrogen radicals to the surface of the insulation film.

Abstract: In a semiconductor manufacturing method, an emitter region (211) and a base enhancement region (207) are formed to provide linear voltage, capacitance and low resistance characteristics. In the manufacturing method, a semiconductor device (200) is formed on a silicon substrate layer (101) with an epitaxial layer (203). Trenches (233) are cut into the epitaxial layer (203) and filled with oxide (601) to provide reduced junction capacitance and reduced base resistance. The emitter region (211) and the base enhancement region (207) are simultaneously formed through an anneal process.

Abstract: In one aspect, the invention provides a method of forming an electrical connection in an integrated circuitry device. According to one preferred implementation, a diffusion region is formed in semiconductive material. A conductive line is formed which is laterally spaced from the diffusion region. The conductive line is preferably formed relative to and within isolation oxide which separates substrate active areas. The conductive line is subsequently interconnected with the diffusion region. According to another preferred implementation, an oxide isolation grid is formed within semiconductive material. Conductive material is formed within the oxide isolation grid to form a conductive grid therein. Selected portions of the conductive grid are then removed to define interconnect lines within the oxide isolation grid. According to another preferred implementation, a plurality of oxide isolation regions are formed over a semiconductive substrate.

Abstract: A method of manufacturing an SOI substrate for semiconductor devices is described. The method includes forming a low density impurity region in a first semiconductor substrate and a high density impurity region in the low density impurity region, forming a trench surrounding the low density impurity region and the high density impurity region, the depth of the trench being deeper than the high density impurity region and shallower than the low density impurity region, forming an insulating layer on the surface of the first semiconductor substrate to fill the inside of the trench, attaching a second semiconductor substrate on the surface of the insulating layer, and removing a part of the first semiconductor substrate so that the bottom of the trench is exposed.

Abstract: Integrated circuit devices including an isolation region are provided. The devices include an integrated circuit substrate and a trench in the integrated circuit substrate that defines an active region of the integrated circuit device. A silicon layer is provided on the integrated circuit substrate that extends over an edge of the trench and along an upper portion of a first sidewall of the trench. An insulating material is positioned adjacent the silicon layer that extends across some, or all, of the trench to define the isolation region. Methods of forming such integrated circuit devices are also provided.

Abstract: A method of fabricating a bipolar transistor structure that provides unit current gain frequency (fT) and maximum oscillation frequency (fMAX) improvements of a raised extrinsic base using non-self-aligned techniques to establish a self-aligned structure. Accordingly, the invention eliminates the complexity and cost of current self-aligned raised extrinsic base processes. The invention forms a raised extrinsic base and an emitter opening over a landing pad, i.e., etch stop layer, then replaces the landing pad with a conductor that is converted, in part, to an insulator. An emitter is then formed in the emitter opening once the insulator is removed from the emitter opening. An unconverted portion of the conductor provides a conductive base link and a remaining portion of the insulator under a spacer isolates the extrinsic base from the emitter while maintaining self-alignment of the emitter to the extrinsic base. The invention also includes the resulting bipolar transistor structure.

Abstract: In one aspect, the invention provides a method of forming an electrical connection in an integrated circuitry device. According to one preferred implementation, a diffusion region is formed in semiconductive material. A conductive line is formed which is laterally spaced from the diffusion region. The conductive line is preferably formed relative to and within isolation oxide which separates substrate active areas. The conductive line is subsequently interconnected with the diffusion region. According to another preferred implementation, an oxide isolation grid is formed within semiconductive material. Conductive material is formed within the oxide isolation grid to form a conductive grid therein. Selected portions of the conductive grid are then removed to define interconnect lines within the oxide isolation grid. According to another preferred implementation, a plurality of oxide isolation regions are formed over a semiconductive substrate.

Abstract: The invention includes a method of forming semiconductor circuitry. A monocrystalline silicon substrate is provided, and a mask is formed which covers a first portion of the substrate and leaves a second portion uncovered. A trench is formed in the uncovered portion and at least partially filled with a semiconductive material that comprises at least one atomic percent of an element other than silicon. The mask is removed and a first semiconductor circuit component is formed over the first portion of the substrate. Also, a second semiconductor circuit component is formed over the semiconductive material that at least partially fills the trench. The invention also includes semiconductor constructions.

Abstract: A semiconductor wafer having a via test structure is provided which includes a semiconductor substrate having a plurality of semiconductor devices. A dielectric layer deposited over the semiconductor substrate has second and fourth channels unconnected to the plurality of semiconductor devices. A via dielectric layer deposited over the channel dielectric layer has first and second vias and third and fourth vias respectively open to opposite ends of the second channel and the fourth channel. A second dielectric layer over the via dielectric layer has first, third, and fifth channels respectively connected to the first via, the second and third vias, and the fourth via. The first channel, the first via, the second channel, the second via, the third channel, the third via, the fourth channel, the fourth via, and the fifth channel are connected in series and the first and fifth channel are probed to determine the presence or absence of voids in the vias.

Abstract: Provided is a method for manufacturing a self-aligned BiCMOS including a SiGe heterojunction bipolar transistor (HBT) for performing high-frequency operations. In this method, an extrinsic base and a selective ion-implanted collector (SIC) are formed by a self-alignment process.

Abstract: A method of forming an isolation trench in a semiconductor includes forming a first isolation trench portion having a first depth and having a first sidewall intersecting a surface of the semiconductor at a first angle. The method also includes forming a second isolation trench portion within and extending below the first isolation trench portion. The second isolation trench portion has a second depth and includes a second sidewall. The second sidewall intersects the first sidewall at an angle with respect to the surface that is greater than the first angle. A dielectric material fills the first and second isolation trench portions.

Abstract: The present invention provides a semiconductor device, a method of manufacture therefor, and an integrated circuit including the same. In one advantageous embodiment, the semiconductor device includes a doped layer located over a semiconductor substrate, and an isolation trench located in the doped layer and having a dielectric layer located on a sidewall thereof. The semiconductor device may further include a conductive material located within the isolation trench and an interconnect that electrically connects the conductive material and the doped layer.

Abstract: A semiconductor wafer is disclosed in which a high concentration impurity layer is formed in a semiconductor wafer to a predetermined depth, in order to electrically connect electrodes formed on the principal face of the wafer without forming trenches and through holes in the wafer. An n++ diffusion region is formed in the dicing region of a semiconductor wafer by ion implanting or diffusion. The diffusion region extends to an n++ layer formed deep in the semiconductor wafer. The width of the n++ diffusion region is made wide enough to account for the blade width of a dicer, so that an n++ diffusion region remains at the outer periphery of each of the chips divided by the dicing operation. Bump electrodes on the wafer surface electrically connect with the n++ layer deep in the semiconductor through the n++ diffusion region.

Abstract: A method of forming buried cavities in a wafer of monocrystalline semiconductor material with at least one cavity formed in a substrate of monocrystalline semiconductor material by timed TMAH etching silicon; covering the cavity with a material inhibiting epitaxial growth; and growing a monocrystalline epitaxial layer above the substrate and the cavities. Thereby, the cavity is completely surrounded by monocrystalline material. Starting from this wafer, it is possible to form a thin membrane. The original wafer must have a plurality of elongate cavities or channels, parallel and adjacent to one another. Trenches are then excavated in the epitaxial layer as far as the channels, and the dividers between the channels are removed by timed TMAH etching.

Abstract: Electrical connection between two faces of a substrate and manufacturing process. The connection is made by a part (46) of a conducting or semi conducting substrate (20) completely surrounded by at least one electrically insulating trench (32, 36, 44). A contact pad (42) is located on the back face (40) and conducting tracks (38) are located on the front face. The connection is made through the substrate itself. Application to the manufacture of circuits, components, sensors, etc.

Abstract: A method of manufacturing vertical NPN and PNP transistors on a substrate includes forming a first oxide film, a P-polycrystal silicon film, and a second oxide film successively on N-silicon epitaxial film on the substrate. An opening is made in the first oxide film to expose the N-silicon epitaxial film and a bottom of the P-polycrystal silicon film anisotropically etching the second oxide film and the P-polycrystal silicon film, and then isotropically etching the exposed first oxide film. A part of the opening is plugged by growing a selective epitaxial layer including a P-monocrystal layer from the surface of the N-silicon epitaxial film, and growing a polycrystal layer from the bottom of the P-polycrystal silicon film. Then, within a PNP transistor section, position and impurity concentration of a P-N junction are adjusted by self-aligned implanting or diffusing of P-impurities into the N-silicon epitaxial layer through the opening.

Abstract: An N− type epitaxial layer is formed on a P− type silicon substrate. Trenches are created so as to penetrate N− type epitaxial layer and so as to reach to a predetermined depth of P− type silicon substrate. Thermal oxide films are formed on the sidewalls of trenches. Buried polysilicon films are formed so as to fill in trenches. Thermal oxide films are formed having an approximately constant film thickness ranging from the bottoms to the edges of the openings of trenches so as not to give stress to N− type epitaxial layers. Thereby, a semiconductor device wherein a leak current is prevented can be gained.

Abstract: The present invention discloses a method for manufacturing a semiconductor device. A device isolation film has a shape of an insulating spacer at an interface of active regions composed of a epitaxial silicon layer in a device isolation region of a semiconductor substrate and active regions composed of a semiconductor substrate, thereby minimizing a size of the device isolation region, maximizing a size of the active regions, and achieving a high integration of the device.

Abstract: In fabricating a shallow trench isolation (STI), a silicon oxide layer, a silicon nitride layer and a moat pattern is sequentially deposited on a silicon substrate. Next, the silicon nitride layer and the silicon oxide layer is etched using the moat pattern as a mask to thereby partially expose the silicon substrate and then the moat pattern is removed. Ion implanting process is performed into the silicon substrate using the silicon nitride layer as a mask, adjusting a dose of an implanted ion and an implant energy, to thereby form an isolation region. And then, the isolation region to form a porous silicon and to form an air gap in the porous silicon is anodized, wherein a porosity of the porous silicon is determined by the dose of the implanted ion. Next, the porous silicon is oxidized through an oxidation process. Finally, the silicon nitride layer is removed.

Abstract: Integrated circuit devices including an isolation region are provided. The devices include an integrated circuit substrate and a trench in the integrated circuit substrate that defines an active region of the integrated circuit device. A silicon layer is provided on the integrated circuit substrate that extends over an edge of the trench and along an upper portion of a first sidewall of the trench. An insulating material is positioned adjacent the silicon layer that extends across some, or all, of the trench to define the isolation region. Methods of forming such integrated circuit devices are also provided.

Abstract: An apparatus including a contact point on a substrate; a first dielectric layer comprising a material having a dielectric constant less than five formed on the contact point, and a different second dielectric layer formed on the substrate and separated from the contact point by the first dielectric layer. Collectively, the first and second dielectric layers comprise a composite dielectric layer having a composite dielectric constant value. The contribution of the first dielectric layer to the composite dielectric value is up to 20 percent. Also, a method including depositing a composite dielectric layer over a contact point on a substrate, the composite dielectric layer comprising a first material having a dielectric constant less than 5 and a second different second material, and forming a conductive interconnection through the composite dielectric layer to the contact point.

Abstract: A low-power bipolar transistor is formed to have a silicon germanium base region, an intrinsic emitter region with a sub-lithographic width, and an oxide layer that is self aligned to an overlying extrinsic emitter. The silicon germanium base region increases the speed of the transistor, while the small extrinsic emitter region reduces the maximum current that can flow through the transistor, and the self-aligned oxide layer and extrinsic emitter reduces the base-to-emitter junction size and device performance variability across the wafer.

Abstract: An integrated circuit arrangement having a number of structural elements, at least one of which is surrounded by a metallic shielding structure. This structural element is thus protected against interference due to disturbing impulses from its environment. In particular, the structural elements of the circuit arrangement can be arranged next to or on top of one another. To produce the metallic shielding structure of a structural element of the circuit arrangement, at least one depression which surrounds the structural element is created and then lined with metal. The contacts and electrical connections of the structural element are electrically insulated from the metal of the shielding structure.

Abstract: In one aspect, the invention provides a method of forming an electrical connection in an integrated circuitry device. According to one preferred implementation, a diffusion region is formed in semiconductive material. A conductive line is formed which is laterally spaced from the diffusion region. The conductive line is preferably formed relative to and within isolation oxide which separates substrate active areas. The conductive line is subsequently interconnected with the diffusion region. According to another preferred implementation, an oxide isolation grid is formed within semiconductive material. Conductive material is formed within the oxide isolation grid to form a conductive grid therein. Selected portions of the conductive grid are then removed to define interconnect lines within the oxide isolation grid. According to another preferred implementation, a plurality of oxide isolation regions are formed over a semiconductive substrate.

Abstract: A trench is formed in an n+ type substrate in a vertical direction from a main surface of the substrate, and a p type layer is deposited in the trench to have a recess portion. An n+ type layer is embedded in the recess portion. Accordingly, the p type layer is formed, as a resistive element, into a U-shape with ends that are ended on the main surface of the substrate. The resistive element has a resistance length corresponding to a path of the U-shape.

Abstract: The present invention relates to a collector pin and a trench in an integrated circuit intended for high speed communication, and to a manufacturing method for these items. The collector pin is achieved by creating an area which is implantation damaged or made amorphous and at least partially doped (139) by means of ion implantation from an upper silicon surface comprised in a semiconductor structure (144) down to a depth lower than the depth of the surrounding field oxide (120), and that the semiconductor structure (144) is then heat treated.

Abstract: Methods of forming integrated circuit capacitors (e.g., DRAM capacitors) include the steps of forming a first capacitor electrode (e.g., polysilicon electrode) on a substrate and then forming a titanium nitride layer on the first capacitor electrode. A tantalum pentoxide dielectric layer is then formed on an upper surface of the titanium nitride layer. A step is then performed to convert the underlying titanium nitride layer into a titanium oxide layer. A second capacitor electrode is then formed on the tantalum pentoxide layer. The step of converting the titanium nitride layer into a titanium oxide layer is preferably performed by annealing the tantalum pentoxide layer in an oxygen ambient in a range between about 700° C. and 900° C. This oxygen ambient provides free oxygen to fill vacancies within the tantalum oxide layer and also provides free oxygen which diffuses into the underlying titanium nitride layer.

Abstract: Increased heat dissipation is provided in a high performance integrated circuit by providing a thermally conductive path from a thermal poly plug (TPP) which extends through a thermal barrier in the substrate, such as in insulator layer of a silicon-on-insulator layer, to a front surface of the chip simultaneously with formation of active device contacts through an insulator layer of said chip. A pad is formed in thermal contact with said thermally conductive path simultaneously and coplanar with wiring connections to active device contacts and a further thermally conductive path may be formed through wiring and/or further insulator layers to a pad for attachment of a passive heat sink or active cooling device coplanar with wire bond pads at a surface of the wiring and/or further insulator layers. Electrical connections to the wire bond pads are formed through optionally insulated apertures in the passive heat sink or active cooling device.

Abstract: A low thermal budget transistor is fabricated by first forming a gate on a semiconductor substrate. First amorphous regions and first inactive dopant regions are then created in the substrate by ion implantation. Sidewall spacers, which align subsequent implantation steps, are formed adjacent to the gate. Thereafter, second amorphous regions and second inactive dopant regions are created in the substrate by ion implantation. Dopants in the first and second inactive dopant regions are then activated using a low temperature annealing process to create source/drain regions and source/drain extension regions. The aforementioned process simplifies the fabrication of a low thermal budget transistor by dispensing with the requirement to remove the sidewall spacers.

Abstract: In connection with the manufacture of chips having partitioned logic, a partitioned mask layout approach. This approach provides the chip exposure pattern as a set of partitions corresponding to macros or core functions and also handles glue logic and interconnect. A result of this approach is a simplified, cost-effective process that does not defer customization to other, potentially more time-consuming and inefficient tasks.

Abstract: A plurality of chips each having two or more alignment holes for transmitting a laser beam are stacked. The laser beam is irradiated onto the uppermost or lowermost one of the stacked chips. A photodetector detects the laser beam output from the stacked chips through the alignment holes in these chips. The positions of the chips are so controlled that the amount of the light detected by this photodetector is a maximum.

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: In one aspect, the invention provides a method of forming an electrical connection in an integrated circuitry device. According to one preferred implementation, a diffusion region is formed in semiconductive material. A conductive line is formed which is laterally spaced from the diffusion region. The conductive line is preferably formed relative to and within isolation oxide which separates substrate active areas. The conductive line is subsequently interconnected with the diffusion region. According to another preferred implementation, an oxide isolation grid is formed within semiconductive material. Conductive material is formed within the oxide isolation grid to form a conductive grid therein. Selected portions of the conductive grid are then removed to define interconnect lines within the oxide isolation grid. According to another preferred implementation, a plurality of oxide isolation regions are formed over a semiconductive substrate.

Abstract: An integrated device having a substrate wherein a buried layer and an epitaxial region have been formed, and an isolation structure adapted to define a plurality of isolation wells for integrating the components of the integrated device therein, the isolation structure including plural dielectrically insulated regions or dielectric trenches being filled with a conductive material to form a plurality of contact regions to buried regions of the device, the buried regions including, in particular, the substrate and buried layer.

Abstract: A method for fabricating bipolar transistor frequently used in high frequency circuit is disclosed herein. The foregoing method includes the following steps. First, a first oxide layer is formed on a p-type substrate, followed by developing a first photoresist pattern on the first oxide layer. A first, doped region is formed in the exposed substrate by a first implanting step. The first doped region comprises a n+ buried layer. Stripping of the first photoresist pattern, and annealing of the n+ buried layer follow. Removal of the first oxide layer to expose the n+ buried layer and a portion of the p-type substrate follows thereafter. These steps are followed by growing a first epitaxial layer on the n+ buried layer and a portion of the substrate, then a second epitaxial layer is formed on the first epitaxial layer. The first epitaxial layer is made of epitaxial n-type silicon, and the second epitaxial layer is made of in situ epitaxial p-type SiGe.

Abstract: A bonded wafer 100 has a device substrate 16 with isolation trenches 30 defining device regions 18. Oxide dogbone structures are removed before filling trenches 30. Voids 36 in the trenches are spaced from the top of the trenches. The trenches are covered with an oxide layer 30 and filled with polysilicon 34. A LOCOS mask structure comprising a layer of CVD pad oxide and silicon nitride 50 cover the trenches and the adjacent device substrate regions.

Abstract: A method for making an improved polysilicon emitter for a bipolar transistor in a BiCMOS integrated circuit is achieved. The method uses a novel stacked undoped amorphous silicon layer and a doped polysilicon layer. The polysilicon layer is doped by ion implantation while the amorphous silicon layer remains undoped. The stacked layer is patterned to form a polysilicon emitter source over the bipolar transistor, while concurrently forming gate electrodes for the FETs. The undoped amorphous silicon layer retards the diffusion from the doped polysilicon to provide a shallower emitter junction during subsequent thermal processing. At a later step a rapid thermal anneal (RTA) is carried out in which the amorphous silicon layer provides better control of the diffused emitter depth (junction) while concurrently activating the implant dopant in the FET source/drain areas.

Abstract: A process for fabricating a bipolar junction transistor, featuring an N type, polysilicon emitter structure, located in an emitter trench, and featuring a narrow width. P type base region, located directly underlying an N type, emitter region, which is formed in the semiconductor substrate, along the vertical and horizontal sides of the emitter trench, has been developed. The process features forming an emitter trench in a semiconductor substrate, followed by a large angle ion implantation procedure, used to form a P type, base region, in an area of the semiconductor substrate located along the sides of the emitter trench. Formation of a polysilicon emitter structure, followed by an anneal cycle, create a narrow width, emitter region, underlying the polysilicon emitter structure, also resulting in the formation of a narrow width, P type base region, located between the overlying N type emitter region, and an underlying N type, epitaxial silicon layer.

Abstract: A method of forming a semiconductor device, wherein, a silicon oxide film formed on a P-type silicon substrate is patterned, after which element separating trenches with a wider aperture width and a buried layer drawing trench with a narrower aperture width are formed at the same time. The buried layer drawing trench is filled with a conductive film such as a tungsten film, which also forms concave parts at the element separating trenches. The semiconductor is exposed at the bottom parts of the element separating trenches to be etched and form complete element separating trenches penetrating through the buried layer.