Abstract: Design of a micro-mirror switching device and its fabrication in single crystal silicon are described. The device is composed of three main elements: silicon mirror plate with metal-mirror, secondary actuator, and hinge/spring mechanism to integrate the mirror plate with the actuator. p-n junction is first formed on p-type silicon. Trenches are then etched in n-silicon to define the device element boundaries and filled with silicon dioxide. Three layers of sacrificial oxide and two structural poly-silicon layers are deposited and patterned to form device elements. Novel release processes, consisting of backside electrochemical etching in potassium-hydroxide, reactive ion etching to expose oxide-filled trenches from the bottom, and hydrofluoric acid etching of sacrificial oxide layers and oxide in silicon trenches, form the silicon blocks; those that are not attached to structural poly-silicon are sacrificed and those that are attached are left in place to hold together the switching device elements.

Abstract: A process is described for trimming photoresist patterns during the fabrication of integrated circuits for semiconductor devices and MEMS devices. A combination of a low temperature (<20° C.), high density oxygen and argon plasma and intense UV radiation is used to simultaneously trim and harden a photoresist linewidth in an ICP chamber. As an alternative, a UV hardening step can be performed in a flood exposure tool prior to the ICP plasma etch. Another option is to perform the argon plasma treatment first to harden the resist and then in a second step apply an oxygen plasma to trim the photoresist. Vertical and horizontal etch rates are decreased in a controllable manner which is useful for producing gate lengths in MOS transistors of less than 100 nm. The process can also be used to controllably increase a space width in a photoresist feature.

Abstract: A method of forming a via-first type dual damascene structure in the absence of an etch stop layer and without via-edge erosion or via-bottom punch-through is described. The invention uses two organic films deposited within via hole prior to trench etching. A via bole over a lower level metal line is first etched in the dielectric film. Two, preferably organic, bottom antireflective coating (BARC) films, first one being the conformal type to coat the surfaces and the walls of the via and the second one being the planarizing type to at least partially fill the via, are then deposited. Using a mask aligned to via hole, a wiring trench of desired depth is etched in the top portion of the dielectric film. During trench etching, the conformal BARC-1 film protects the via-edges from eroding and the planarizing BARC-2 film prevents punch-through of the via-bottom. Desired metal such as aluminum or copper are deposited within said dual damascene pattern.

Abstract: An accelerometer design is described. It operates by measuring a change in capacitance when one plate is fixed and one is mobile (free to accelerate). Unlike prior art designs where such changes are caused by variations in the plate separation distance, in the design of the present invention the plate separation distance is fixed, it being the effective plate area that changes with acceleration. A key feature is that the basic unit is a pair of capacitors. The fixed plates in each case are at the same relative height but the mobile plates are offset relative to the fixed plates, one mobile plate somewhat higher than its fixed plate with the other mobile plate being somewhat lower. Then, when the mobile plates move (in the same direction), one capacitor increases in value while the other decreases by the same amount. This differential design renders the device insensitive to sources of systematic error such as temperature changes. A process for manufacturing the design is described.

Abstract: A method for spin coating a polymeric material film upon a wafer rotatably mounted within a spin coater; the wafer having a surface, including the following steps. A first step of rotating the wafer on an axis perpendicular to the wafer surface while applying a predetermined amount of polymeric material while rotating the wafer at a rotational speed of from about 300 to 1200 rpm for from about 2.5 to 5 seconds to spread the polymeric material on the whole surface of the wafer. A second step of increasing the rotational speed of the wafer to about 5500 rpm for about 2.5 seconds. A third step of decreasing the rotational speed of the wafer to about 300 to 1200 rpm for about 2.5 seconds. A fourth step of increasing the rotational speed of the wafer to about 5500 rpm for about 20 seconds to form the polymeric material film having a predetermined thickness over the whole surface of the wafer.

Abstract: A process to form a capillary that is well insulated from its environment is described. Said process has two stages. The first stage, which is the same for both of the invention's two embodiments, comprises forming a micro-channel in the surface of a sheet of glassy material. For the first embodiment, this sheet is bonded to a layer of oxide, that lies on the surface of a sheet of silicon, thereby sealing in the capillary. After all silicon has been selectively removed, a thin membrane of oxide remains. Using a low temperature bonding process, a second sheet of glassy material is then bonded to this membrane. In the second embodiment, the silicon is not fully removed. Instead, the oxide layer of the first embodiment is replaced by an oxide/nitride/oxide trilayer which provides improved electrical insulation between the capillary and the remaining silicon at a lower level of inter-layer stress.

Abstract: Disclosed is a single-stage, switched capacitor circuit for measuring changes in a variable by measuring changes in a capacitor gap. The change in the capacitor gap corresponds directly to a change in a measurable variable, such as pressure and acceleration, and thus a change in voltage. The circuit includes at least one reference capacitor, a sensor capacitor, a plurality of switches responsive to a timing device, and a device for generating substantially constant reference voltages. The sensor circuit does not result in a DC offset value, but results in the AC component of the voltage being directly proportional to the change in the variable through a substantially constant voltage is supplied to a node near the sensor capacitance. The circuit may be trimmed using a digital to analog converter and/or capacitors coupled in parallel.

Abstract: A lead-frame for connecting and supporting an integrated circuit having an apertured frame with dimensions smaller than the corresponding dimensions of the chip so that chip-pad shoulder can be eliminated and the chip attach fillet is made remote from the chip corner.

Abstract: Planarization of the top surfaces of layers that are more than about a micron thick is beset with problems not encountered in thinner layers. These problems have been overcome by means of a process that, initially allows the formation of ‘horns’ in the surface that is to be planarized. Said horns are then selectively etched away while other parts of the surface are protected, following which CMP is initiated and the surface gets planarized. A total of four embodiments are disclosed.

Abstract: A layout of a carrier in an optical component having the carrier and an optical device is described. The layout comprises a pair of terminals, a resistor connected to a first terminal, a wire bond connected in series with the resistor for connecting the resistor to an optical device, and a first ground patch connected to a second terminal and for connecting to an optical device for providing a common ground on a first surface on a substrate on which the carrier is based, whereby the pair of terminals, the resistor, the wire bond and an optical device form an optical signal transmission system in the optical component.

Abstract: When using hot alkaline etchants such as KOH, the wafer front side, where various devices and/or circuits are located, must be isolated from any contact with the etchant. This has been achieved by using two chambers that are separated from each other by the wafer that is to be etched. Etching solution in one chamber is in contact with the wafer's back surface while deionized water in the other chamber contacts the front surface. The relative liquid pressures in the chambers is arranged to be slightly higher in the chamber of the front surface so that leakage of etchant through a pin hole from back surface to front surface does not occur. As a further precaution, a monitor to detect the etchant is located in the DI water so that, if need be, etching can be terminated before irreparable damage is done.

Abstract: A chip scale package (CSP) comprises a flip chip and chip carrier with features to enhance its electrical and thermal performance. The flip chip connects to the chip carrier through alternating signal and ground connections. Top layer routing on the chip carrier substantially maintains ground-based guard isolation between neighboring signal lines. The arrangement of inter-layer vias and bottom layer traces also maintains the isolation for flip chip signals routed to the bottom layer of the chip carrier, where they are available for interconnection with a primary circuit board via solder balls or the like. The bottom layer further includes a centralized ground plane. Special thermal vias extend from the top layer into this bottom layer ground plane. Dedicated solder ball connections for the ground plane provide a ground path between the flip chip and the primary circuit with very low electrical and thermal impedances.

Abstract: The invention relates to a high frequency board-to-board connector for interconnecting electronic sub-assemblies. The high frequency board-to-board connector includes a row of conductive pins received in an insulative housing for connecting with receptacles of a design. Two discrete electronic sub-assemblies, for example PCBs, can be mechanically and electrically connected without the need for a gender male connector on one PCB and a corresponding gender female connector on the other PCB. A plurality of follower arms spaced apart along the grounding plate facilitates contact with a ground plane in the design to form a ground path. The ground path reduces electromagnetic coupling between any pair of conductive pins and consequentially lowering cross-talk noise. Furthermore, inductive parasitics of the conductive pins is reduced, further facilitating high frequency operations.

Abstract: A lead-frame for connecting and supporting an integrated circuit chip with a chip accommodating zone with inwardly extending ears for supporting the chip including minimum shoulder area, and having open crack and delamination stopping regions.

Abstract: A high frequency CMOS differential amplifier which comprises: a variable gain amplifier which amplifies differential input; a temperature sensing circuit; a gain-slope correction circuit which produces an intermediate control voltage as a function of temperature, thereby compensating for a change in slope of the gain control characteristics with temperature of the variable gain amplifier; a gain compensation circuit which is used to correct temperature/process variations of MOS transistors in high frequency differential amplifiers; and a bias control circuit.

Abstract: An accelerometer design is described. It operates by measuring a change in capacitance when one plate is fixed and one is mobile (free to accelerate). Unlike prior art designs where such changes are caused by variations in the plate separation distance, in the design of the present invention the plate separation distance is fixed, it being the effective plate area that changes with acceleration. A key feature is that the basic unit is a pair of capacitors. The fixed plates in each case are at the same relative height but the mobile plates are offset relative to the fixed plates, one mobile plate somewhat higher than its fixed plate with the other mobile plate being somewhat lower. Then, when the mobile plates move (in the same direction), one capacitor increases in value while the other decreases by the same amount. This differential design renders the device insensitive to sources of systematic error such as temperature changes. A process for manufacturing the design is described.

Abstract: A process for fabricating an integrated circuit sensor/actuator is described. High aspect ratio deep silicon beams are formed by a process of deep trench etch and silicon undercut release etch by using oxide spacers to protect the silicon beam sidewalls during release etch. An oxide layer is then formed, followed by deposition of a controlled thickness of polysilicon which is then thermally oxidized. The polysilicon layer inside the trenches gets fully oxidized resulting in void-free trench isolation. This process creates a silicon island or beam on three sides leaving the third side for interfacing with the sensor/actuator beams. The sensor/actuator is formed by a similar process of deep trench etch and release etch process on the same substrate. These suspended beams of the sensors and actuators are bridged with the silicon islands from the fourth side. The above process finally results in suspended silicon beams connected to electrically isolated silicon islands.

Abstract: One of the limitations to current usage of scanning thermal microscopes arises when one needs to obtain a thermal map of an electrically biased specimen. Current practice is for the conductive parts of the specimen to be passivated to prevent excessive current leakage between the tip and the conductive sample. The present invention eliminates the need for this by coating the probe's microtip with a layer of insulation that is also a good thermal conductor. Examples of both thermocouple and thermistor based probes are given along with processes for their manufacture.

Abstract: A wide-band single-ended to differential converter (DC to 1 GHz) with very low amplitude and phase matching errors, of the order of 0.01 dB and 0.15 degrees respectively and using CMOS technology, is comprised of a first and a second stage. The very low amplitude and phase matching errors have been achieved firstly by the use of capacitive means CD across the gate and source of the first stage MOS transistor M1 with a value equal to the drain to ground (reference potential) parasitic capacitance of the tail current source device for the first stage, and secondly by using equal valued capacitive means CF1, CF2 in the second stage and setting their values to be several (5-10) times more than the gate-drain parasitic capacitances of either of the differential transistors of the second stage.

Abstract: A novel silicon RF LDMOSFET structure based on the use of a stacked LDD, is disclosed. The LDD has been modified from a single layer of N type material to a stack of three layers. These are upper and lower N type layers with a P type layer between them. The upper N type layer is heavily doped to reduce the on-resistance of the device, while the lower N type layer is lightly doped to reduce the output capacitance, thereby improving the high frequency performance. The middle P layer is heavily doped which allows it to bring about pinch-off of the two N layers, thereby raising the device's breakdown voltage. A process for manufacturing the device, as well as experimental data concerning its performance are also given.