Abstract: A process for forming a bipolar transistor with a raised extrinsic base, an emitter, and a collector integrated with a CMOS circuit with a gate. An intermediate semiconductor structure is provided having CMOS and bipolar areas. An intrinsic base layer is provided in the bipolar area. A base oxide is formed across, and a sacrificial emitter stack silicon layer is deposited on, both the CMOS and bipolar areas. A photoresist is applied to protect the bipolar area and the structure is etched to remove the sacrificial layer from the CMOS area only such that the top surface of the sacrificial layer on the bipolar area is substantially flush with the top surface of the CMOS area. Finally, a polish stop layer is deposited having a substantially flat top surface across both the CMOS and bipolar areas suitable for subsequent chemical-mechanical polishing (CMP) to form the raised extrinsic base.

Abstract: A device for creating at least one aligned marking on opposite sides of a semiconductor wafer including a front side and a back side. A wafer receiving support unit including at least a first wafer receiving slot in a first side wall thereof receives a wafer inserted therein. A template positions at least one aligned marking on each of the front side of the semiconductor wafer and on the backside of the semiconductor wafer.

Abstract: A process for fabricating a tapered trench on a silicon substrate. The process comprises the steps of forming an initial trench in the substrate and implanting nitrogen ions on the initial trench side walls. More nitrogen ions are implanted adjacent the exposed surface of the substrate than adjacent the trench bottom. Finally, the initial trench side walls are oxidized to create the tapered shape.

Abstract: A process for making a SOI region and a bulk region in a semiconductor device. The process includes providing a SOI structure. The SOI structure has a thin silicon layer, a buried insulating oxide layer underlying the thin silicon layer, and a silicon substrate underlying the buried insulating oxide layer. Next, a nitride layer is deposited on top of the SOI structure. The SOI structure is exposed by selectively etching portions of the nitride layer. The portion of the nitride layer which is not etched forms the SOI region. The silicon substrate is exposed by selectively etching the remaining portion of the exposed SOI structure. An epitaxial layer is grown on top of the exposed silicon substrate to form the bulk region. The nitride portion above the SOI structure is finally removed.

Abstract: A SOI field effect transistor structure providing ESD protection. The structure has a source, a drain, a body, and a gate. The gate is formed from a thick oxide layer and a metal contact. The gate s formed during the BEOL process. The transistor may by a p-type transistor or an n-type transistor. The transistor may have its drain tied to either the gate, the body, or both the gate and body. When used as a protection device, the drain is tied to a signal pad and the source is tied to a potential reference.

Abstract: A process for forming a silicon-germanium base of a heterojunction bipolar transistor. First, a silicon substrate having a mesa surrounded by a trench is formed. Next, a silicon-germanium layer is deposited on the substrate and the portion of the silicon-germanium layer adjacent the mesa is removed to form the silicon-germanium base. In a second embodiment, the process comprises the steps of forming a silicon substrate having a mesa surrounded by a trench, forming a dielectric layer in the trench adjacent the mesa, and growing a silicon-germanium layer on the mesa top surface using selective epitaxial growth to form the silicon-germanium base.

Abstract: A method for forming a structure. A first dielectric material is deposited on a substrate. The first dielectric material is patterned. At least one metal is deposited in and on the first dielectric material. Portions of the at least one metal are removed at least in a region above an upper surface of the first dielectric material. The first dielectric material is removed. A second dielectric material is provided in place of first dielectric material.

Abstract: A mixer for a wireless communications system having a differential amplifier that translates an input intermediate frequency voltage signal or an input radio frequency voltage signal to current signals that are supplied to a doubly-balanced switching modulator that develops a differential mixed output radio frequency signal or intermediate frequency signal that is the product of the current signals and a local oscillator signal. Included in the differential amplifier are a first reactance circuit and a second reactance circuit each of which provides a low impedance to ground at the second harmonic of the local oscillator signal and a high impedance at the frequency of the input radio frequency signal or input intermediate frequency signal.

Abstract: A planar silicon-on-insulator (SOI) structure and a process for fabricating the structure. The SOI structure has a silicon wafer, an oxide layer, and a silicon layer. Trenches are formed, extending from the top surface of the structure to the silicon wafer, and are filled with a semiconductor. The trenches have a top, a bottom, and side walls. The side walls have side-wall silicon portions. The side-wall silicon portions of the trench side walls are covered by trench side-wall oxide layers. A protective side wall extends over the trench side walls and trench side-wall oxide layers from the trench top to the trench bottom.

Abstract: A balun transformer having two series connected transformers with each having a primary loop conductor disposed in a stacked configuration. One portion of each primary loop conductors is in a first layer and these two portions of the two primary loop conductors are connected in series. The second portions of the primary loop conductors are in a second layer that is spaced from the first layer with the secondary loop conductors interlaced with these portions of the primary loop conductors in the second layer.

Abstract: A multi-chip module and heat-sink cap assembly and method of fabrication, which provides sufficient cooling for higher power density chips. The heat-sink cap has heat-sink columns disposed over each chip on a substrate. The heat-sink columns are interconnected by flexible members to provide a unitary cover. Thin film metallization of at least a portion of the mating surfaces of the substrate, chips and heat-sink column permits soldering of the cap to the chips and substrate to form the package which is a mechanically stable structure with no degradation of interconnection fatigue life due to thermal cycling of the assembly when in use.

Abstract: A process for removing material from a substrate. The material is exposed to an aqueous solution comprising about 4% to about 30% of at least one acid and at least one surfactant.

Abstract: A p-type MOSFET having very shallow p-junction extensions. The semiconductor device is produced on a substrate by creating a layer of implanted nitrogen ions extending from the substrate surface to a predetermined depth preferably less than about 800 Å. The gate electrode serves as a mask so that the nitrogen implantation does not filly extend under the gate electrode. Boron is also implanted to an extent and depth comparable to the nitrogen implantation thereby forming very shallow p-junction extensions that remain confined substantially within the nitrogen layer even after thermal treatment. There is thus produced a pMOSFET having very shallow p-junction extensions in a containment layer of nitrogen and boron in the semiconductor material.

Abstract: A semiconductor device structure including a substrate including at least one silicon-on-insulator substrate region and at least one non-silicon-on-insulator region. The at least one silicon-on-insulator region and at least one non-silicon-on-insulator region are formed in a pattern in the substrate. At least one trench is arranged in the vicinity of at least at a portion of a boundary between a silicon-on-insulator substrate region and the non-silicon-on-insulator substrate region. The at least one trench is arranged in at least one of the silicon-on-insulator region and the non-silicon-on-insulator region.

Abstract: A multipurpose current source for generating a current with linear positive temperature dependence at a predetermined slope. This multipurpose current source includes a proportional to absolute temperature (PTAT) current source, a constant current generation circuit coupled to the PTAT current source circuit and a circuit coupled to the PTAT current source circuit and the constant current generation circuit by which a temperature dependent current developed by the PTAT current source and a constant current independent of temperature developed by the constant current generation circuit are combined The linear positive temperature dependent current is generated by subtracting to develop a temperature dependent current by reducing the temperature dependent current developed by the PTAT current source by the constant current independent of temperature developed by the constant current generation circuit.

Abstract: An amplifier in which the gain is changed by changing the reactance in the emitter of a transistor and this change in reactance is compensated for by changing the reactance in a feedback path between the collector and the base of the transistor to maintain the input impedance to the amplifier fixed.

Abstract: A process for making a capacitor for a silicon-on-insulator (SOI) structure. The SOI structure has a p-type silicon base layer, a buried oxide layer, a silicon layer, and an n+ layer formed within a portion of the p-type silicon base layer. The process comprises the steps of forming a buried oxide layer and a silicon layer in the p-type silicon base layer, forming an n+ layer in a portion of the p-type silicon base layer, and forming electrically conductive paths to the p-type silicon base layer and the n+ layer extending through the buried oxide and silicon layers.

Abstract: A voltage regulator that establishes a bandgap voltage reference and achieves output voltage regulation with a single feedback loop. The bandgap voltage reference is established by equal current flow through each of two branches of a proportional to absolute temperature current mirror. The equal current flow through the two branches of the proportional to absolute temperature current mirror is achieved by the feedback loop controlling the current flow in response to the bandgap voltage reference. This same feedback loop, responsible for establishing the bandgap voltage, also establishes the regulated output voltage through a pass transistor by means of maintaining a fixed voltage ratio between the bandgap voltage and the regulated output voltage through a resistor string.

Abstract: A radio frequency power amplifier for a battery powered handset unit of a wireless communications system having a low power signal amplification path and a high power signal amplification path. Logic and biasing means within the handset select between the low power signal path and the high power signal depending upon the handset being within or outside a prescribed distance from a base station. In this way, the signals received at the base station from the handset are at the required power level.

Abstract: An SOI chip having an isolation barrier. The SOI chip includes a substrate, an oxide layer deposited on the substrate, and a silicon layer deposited on the oxide layer. A gate is deposited above the silicon layer. A first metal contact is deposited above the gate to form an electrical contact with the gate. Second and third metal contacts are deposited to form electrical contacts with the silicon layer. The isolation barrier extends through the silicon layer and the oxide layer, and partially into the substrate, to block impurities in the oxide layer outside the isolation barrier from diffusing into the oxide layer inside the isolation barrier. The isolation barrier surrounds the gate, the first metal contact, the second metal contact, and the third metal contact—which define an active chip area inside the isolation barrier. A method of manufacturing the SOI chip is also disclosed.