Abstract: A method of planarizing a dielectric coating applied over an underlying structure on an integrated circuit wafer employs a two-step chemical mechanical polishing (CMP) process. The underlying structure is characterized as having elevated areas and recessed areas. The wafer can be prepared by applying a first polish stop on the elevated areas, then depositing a layer of dielectric over at least the recessed areas, and finally depositing a second polish stop over the resulting dielectric coating. In some applications a first polish stop is not required. The first step in the two-step CMP is polishing the second polish stop using a slurry that polishes the second polish stop until the second polish stop is substantially removed over the elevated areas. The second step is polishing the dielectric coating that remains using a second slurry that polishes the dielectric at a faster rate than it polishes either the second or first polish stop.

Abstract: A monolithic optocoupler having a light emitting diode for emitting light, a first photodiode for producing a current based on light sensed by it, a second photodiode for producing a current based on light sensed by it and an insulator for electrically isolating the light emitting diode from the first photodiode. The insulator is substantially transparent to light emitted by the light emitting diode. The first and second photodiodes are positioned with respect to the light emitting diode such or that directional non-uniformities of light emitted by the light emitting diode are compensated.

Abstract: Metal silicide is removed at a faster rate than polysilicon in dry etching of metal silicide/polysilicon composites with an etching gas made from HCl and Cl.sub.2 at a volumetric flowrate ratio of HCl:Cl.sub.2 within the range of 3:1 to 5:1.

Abstract: An energy relieving, redundant crack stop and the method of producing the same is disclosed. The redundant pattern allows the crack propagating energy that is not absorbed by the first ring of metallization to be absorbed by a second area of metallization and also provides a greater surface area over which the crack producing energy may be spread. The redundant crack stop is produced during the metallization process along with the rest of the wiring of the chip surface and, therefore, no additional production steps are necessary to form the structure.

Abstract: The preferred embodiment provides an integrated circuit capacitor that achieves a high capacitance by using an inversion layer in the substrate as the plate counter electrode for the capacitor. The inversion layer is created by forming a trench capacitor in a lightly doped substrate. With a sufficient workfunction difference between the storage node material and the isolation band the surface of the lightly doped substrate inverts, with the inversion charge being supplied by the isolation band. This inversion layer serves as the plate counter electrode for the capacitor.

Abstract: Isolation and interconnection of a telephone network of tip and ring lines and the analog ports of a modem are achieved with a transhybrid that incorporates optically-coupled isolation stages. Optical isolators directly connect to the tip and ring lines to provide optimal isolation and unidirectional transfer of signals.

Abstract: Optical feedback control in an optical emitter-detector combination can be improved by fabricating the two devices on a single substrate. The feedback radiation can then travel within a monolithic structure. This arrangement will yield greater uniformity in devices as well as provide for easier mechanical assembly.

Abstract: An integrated circuit (IC) (20) is formed on a semiconductor substrate (21). The IC has a PN junction (28) and a graded junction termination (27). A reverse field plate (31) is mounted adjacent the junction termination. One end of the field plate is mounted on and electrically connected to the substrate; the remainder of the field plate extends over a passivating oxide layer (30) which covers the substrate surface (29) adjacent the junction termination. The field plate provides a common potential surface which maintains a fixed potential on the substrate surface at the junction termination.

Abstract: A data access arrangement (DAA) having a transhybrid circuit for separating a transmit signal from a received signal by providing a transmit cancellation signal to the inverting input of a servo-feedback differential amplifier on the receive channel of the DAA. The cancellation signal is provided by a photodiode optically coupleable with a light emitting diode within a optical isolator on the transmission channel of the DAA. The gain of the cancellation signal can be independently controlled.

Abstract: A method of making a data access arrangement (DAA) device. The method includes providing a substrate with a DAA circuit, containing optically active electrical components, mounted on it and individually encapsulating each optically active component with an optical medium. An opaque material is transfer molded about the substrate to completely encase the substrate and all of the circuit components. Before the transfer molding, a lead frame is attached to the substrate that extends through and beyond the opaque material to enable electrical contact with the substrate and the circuit components.

Abstract: A method for establishing a light pathway for an optics apparatus that is substantially free of misalignment. The various components of the apparatus, such as a light source, a light modulator and a light detector, are positionally configured and fixed relative to one another and to a single reference datum in a manner to establish and maintain a continuous light pathway.

Abstract: An optical encoder for a rotating shaft having a radiation source, a radiation detector and a radiation modulator interposed therebetween. The radiation source, the radiation modulator and the radiation detector are positionally configured and mechanically connected to one another and to the shaft in a manner to be in axial and radial alignment with one another relative to the rotating shaft.

Abstract: A multilayer interconnect structure for a semiconductor integrated circuit comprising a base layer of titanium, a second layer of titanium nitride, a third layer of an aluminum alloy and a top layer of titanium nitride. All of the layers contained within the multilayer interconnect structure are deposited by in-situ deposition in an ultra-high vacuum deposition system. The different layers deposited in the deposition system are conducted consecutively without a disruption to the vacuum. Although each layer in the multilayer interconnect structure are deposited within the integrated ultra-high vacuum deposition system, with multiple deposition chambers, the deposition of the different layers is conducted at different temperatures. The time to the electromigration failure of the multilayer interconnect structure, caused by the electromigration of the aluminum alloy, is greatly increased by depositing the aluminum alloy layer at a temperature in excess of 300.degree. C. and preferably between 350.degree. C.

Abstract: A complex building agent, such as EDTA is added in a predetermined concentration to the "SC 1" step of a "PIRANHA-RCA" cleaning sequence for reducing the metal contamination left on the surface of a silicon wafer after completion of this cleaning step.

Abstract: A method of making a monolithic structure for an optocoupler that provides improved linearity. The method includes forming an output signal photodiode and a feedback control signal photodiode on a single chip with an LED. The photodiodes are configured and positioned relative to the LED to compensate for any non-uniformities in the light received from the LED.

Abstract: A data access arrangement (DAA) having a transhybrid circuit for separating a transmit signal from a received signal by providing a transmit cancellation signal to the inverting input of a servo-feedback differential amplifier on the receive channel of the DAA. The cancellation signal is provided by a photodiode optically coupleable with a light emitting diode within a optical isolator on the transmission channel of the DAA. The gain of the cancellation signal can be independently controlled.

Abstract: Isolation and interconnection of a telephone network of tip and ring lines and the analog ports of a modem are achieved with a transhybrid that incorporates optically-coupled isolation stages. Optical isolators connect to the tip and ring lines to provide optimal isolation and unidirectional transfer of signals.

Abstract: Bidirectional isolated interfaces using optical couplers offer a compact and cost-effective alternative to traditional line transformers. The devices can be configured to provide half-duplex or full-duplex communication.

Abstract: An optically-triggered silicon controlled rectifier (SCR) device (21) mounted on a lead frame (34). The SCR device contains a cathode layer (24), an optical gate or control layer (23), and an anode layer (31) formed on a semiconductor substrate (22). The device is soldered onto a pedestal (33) formed on the lead frame. To connect the device to the lead frame, solder is deposited upon the anode layer and the solder fixes the anode layer to the pedestal on the lead frame. The pedestal may be formed by etching or stamping a depression (35) in the lead frame. The device is centered on the pedestal such that the edges of the device are located adjacent the depression, and are spaced from the lead frame.

Abstract: An optically triggered silicon controlled rectifier (SCR) circuit (20) has a number of semiconductor layers diffused into an N- substrate (21). The layers form an SCR (50) having a P+ anode region (25), a P+ gate region (24), and an N+ cathode region (27). An adjustable base-shunt resistance, in the form of a P- channel depletion mode MOSFET (Q3), connects between the SCR gate region and the cathode region. The MOSFET includes a MOSFET gate region (35), a P+ drain region (24), a P-- channel (26), and a P+ source region (23). The substrate also accommodates a PN photodiode (22, D1) which connects to the MOSFET gate region for switching the MOSFET on and off in response to incident optical radiation (L) thereon. The SCR gate region also comprises photosensitive material. When sufficient optical radiation illuminates the photodiode and the SCR gate region, the MOSFET is turned off and the SCR is triggered, permitting anode-to-cathode current to flow.