Patent application number | Description | Published |
20080225574 | MEMORY CELL WITH INDEPENDENT-GATE CONTROLLED ACCESS DEVICES AND MEMORY USING THE CELL - A memory cell includes double-gate first and second access devices configured to selectively interconnect cross-coupled inverters with true and complementary bit lines. Each access device has a first gate connected to a READ word line and a second gate connected to a WRITE word line. During a READ operation, the first and second access devices are configured to operate in a single-gate mode with the READ word line “ON” and the WRITE word line “OFF” while the double-gate pull-down devices are configured to operate in a double gate mode. During a WRITE operation, the first and second access devices are configured to operate in a double-gate mode with the READ word line “ON” and the WRITE word line also “ON.” | 09-18-2008 |
20080273374 | METHODS OF OPERATING AND DESIGNING MEMORY CIRCUITS HAVING SINGLE-ENDED MEMORY CELLS WITH IMPROVED READ STABILITY - A memory cell for interconnection with READ and WRITE word lines and READ and WRITE bit lines includes a logical storage element such as a flip-flop formed by a first inverter and a second inverter cross-coupled to the first inverter. The storage element has first and second terminals and a storage element supply voltage terminal configured for interconnection with a first supply voltage. A WRITE access device is configured to selectively interconnect the first terminal to the WRITE bit line under control of the WRITE word line, and a pair of series READ access devices are configured to ground the READ bit line when the READ word line is active and the second terminal is at a high logical level. A logical “one” can be written to the storage element when a second supply voltage, greater than the first supply voltage, is applied to the WRITE word line, substantially without the use of a complementary WRITE bit line. | 11-06-2008 |
20080276205 | COMPUTER PROGRAM PRODUCT FOR DESIGNING MEMORY CIRCUITS HAVING SINGLE-ENDED MEMORY CELLS WITH IMPROVED READ STABILITY - A memory cell for interconnection with READ and WRITE word lines and READ and WRITE bit lines includes a logical storage element such as a flip-flop formed by a first inverter and a second inverter cross-coupled to the first inverter. The storage element has first and second terminals and a storage element supply voltage terminal configured for interconnection with a first supply voltage. A WRITE access device is configured to selectively interconnect the first terminal to the WRITE bit line under control of the WRITE word line, and a pair of series READ access devices are configured to ground the READ bit line when the READ word line is active and the second terminal is at a high logical level. A logical “one” can be written to the storage element when a second supply voltage, greater than the first supply voltage, is applied to the WRITE word line, substantially without the use of a complementary WRITE bit line. | 11-06-2008 |
20080278992 | INDEPENDENT-GATE CONTROLLED ASYMMETRICAL MEMORY CELL AND MEMORY USING THE CELL - Techniques are provided for employing independent gate control in asymmetrical memory cells. A memory circuit, such as an SRAM circuit, can include a number of bit line structures, a number of word line structures that intersect the bit line structures to form a number of cell locations, and a number of asymmetrical memory cells located at the cell locations. Each of the asymmetrical cells can be selectively coupled to a corresponding one of the bit line structures under control of a corresponding one of the word line structures. Each of the cells can include a number of field effect transistors (FETS), and at least one of the FETS can be configured with separately biased front and back gates. One gate can be biased separately from the other gate in a predetermined manner to enhance read stability of the asymmetrical cell. | 11-13-2008 |
20090067223 | COMPUTER-READABLE MEDIUM ENCODING A BACK-GATE CONTROLLED ASYMMETRICAL MEMORY CELL AND MEMORY USING THE CELL - Techniques are provided for back-gate control in an asymmetrical memory cell. In one aspect, the cell includes five transistors and can be employed for static random access memory (SRAM) applications. An inventive memory circuit can include a plurality of bit line structures, a plurality of word line structures that intersect the plurality of bit line structures to form a plurality of cell locations, and a plurality of cells located at the plurality of cell locations. Each cell can be selectively coupled to a corresponding one of the bit line structures under control of a corresponding one of the word line structures. Each cell can include a first inverter having first and second field effect transistors (FETS) and a second inverter with third and fourth FETS that is cross-coupled to the first inverter to form a storage flip-flop. One of the FETS in the first inverter can be configured with independent front and back gates and can function as both an access transistor and part of one of the inverters. | 03-12-2009 |
20090070716 | SYSTEM AND METHOD FOR OPTIMIZATION AND PREDICATION OF VARIABILITY AND YIELD IN INTEGRATED CIRUITS - A system and method for designing a circuit includes generating physics based equations to describe phenomena of a circuit component, representing physical device geometry by correlating the physical device geometry with features of a circuit component design, and integrating the physical based equations and correlated physical device geometry into a computer based model to represent aspects of behavior and geometry for the circuit component. The circuit component is modeled in the presence of variability by statistically analyzing a design space defined by a plurality of parameters in the physics based equations and the physical device geometry to optimize at least one of cost and yield to determine an optimal design point. The circuit component is provided using the optimal design point. | 03-12-2009 |
20090302354 | High Density Stable Static Random Access Memory - A memory circuit includes a plurality of bit line structures, a plurality of word line structures intersecting the plurality of bit line structures to form a plurality of cell locations; and a plurality of cells located at the plurality of cell locations. Each of the cells is selectively coupled to a corresponding one of the bit line structures under control of a corresponding one of the word line structures, and each of the cells in turn includes a logical storage element having at least a first n-type field effect transistor and at least a first p-type field effect transistor. The at least first n-type field effect transistor is formed with a relatively thick buried oxide layer sized to reduce capacitance of the bit line structures, and the at least first p-type field effect transistor is formed with a relatively thin buried oxide layer | 12-10-2009 |
20090302894 | DUAL GATE TRANSISTOR KEEPER DYNAMIC LOGIC - A dynamic logic gate has a device for charging a dynamic node during a pre-charge phase of a clock. A logic tree evaluates the dynamic node with a device during an evaluate phase of the clock. The dynamic node has a keeper circuit comprising an inverter with its input coupled to the dynamic node and its output coupled to the back gate of a dual gate PFET device. The source of the dual gate PFET is coupled to the power supply and its drain is coupled to the dynamic node forming a half latch. The front gate of the dual gate PFET is coupled to a logic circuit with a mode input and a logic input coupled back to a node sensing the state of the dynamic node. The mode input may be a slow mode to preserve dynamic node state or the clock delayed that turns ON the strong keeper after evaluation. | 12-10-2009 |
20090302929 | Methods and Apparatus for Varying a Supply Voltage or Reference Voltage Using Independent Control of Diode Voltage in Asymmetrical Double-Gate Devices - Methods and apparatus are provided for varying one or more of a supply voltage and reference voltage in an integrated circuit, using independent control of a diode voltage in an asymmetrical double-gate device. An integrated circuit is provided that is controlled by one or more of a supply voltage and a reference voltage. The integrated circuit comprises an independently controlled asymmetrical double-gate device to adjust one or more of the supply voltage and the reference voltage. The independent control may comprise, for example, a back gate bias. The independently controlled asymmetrical double-gate device may be employed in a number of applications, including voltage islands, static RAM, and to improve the power and performance of a processing unit. | 12-10-2009 |
20090303778 | Methods and Apparatus for Varying a Supply Voltage or Reference Voltage Using Independent Control of Diode Voltage in Asymmetrical Double-Gate Devices - Methods and apparatus are provided for varying one or more of a supply voltage and reference voltage in an integrated circuit, using independent control of a diode voltage in an asymmetrical double-gate device. An integrated circuit is provided that is controlled by one or more of a supply voltage and a reference voltage. The integrated circuit comprises an independently controlled asymmetrical double-gate device to adjust one or more of the supply voltage and the reference voltage. The independent control may comprise, for example, a back gate bias. The independently controlled asymmetrical double-gate device may be employed in a number of applications, including voltage islands, static RAM, and to improve the power and performance of a processing unit. | 12-10-2009 |
20100026346 | HIGH-DENSITY LOGIC TECHNIQUES WITH REDUCED-STACK MULTI-GATE FIELD EFFECT TRANSISTORS - Techniques for employing multi-gate field effect transistors (FETS) in logic circuits formed from logic gates are provided. Double-gate transistors that conduct only when both transistor gates are active can be used to reduce the number of devices hitherto required in series or “stacked” portions of logic gates. Circuit area can be reduced and performance can be enhanced. | 02-04-2010 |
20100195373 | Method of Operating a Memory Circuit using Memory Cells with Independent-Gate Controlled Access Devices - A memory cell includes double-gate first and second access devices configured to selectively interconnect cross-coupled inverters with true and complementary bit lines. Each access device has a first gate connected to a READ word line and a second gate connected to a WRITE word line. During a READ operation, the first and second access devices are configured to operate in a single-gate mode with the READ word line “ON” and the WRITE word line “OFF” while the double-gate pull-down devices are configured to operate in a double gate mode. During a WRITE operation, the first and second access devices are configured to operate in a double-gate mode with the READ word line “ON” and the WRITE word line also “ON.” | 08-05-2010 |
20110173577 | Techniques for Pattern Process Tuning and Design Optimization for Maximizing Process-Sensitive Circuit Yields - Techniques for improving circuit design and production are provided. In one aspect, a method for virtual fabrication of a process-sensitive circuit is provided. The method comprises the following steps. Based on a physical layout diagram of the circuit, a virtual representation of the fabricated circuit is obtained that accounts for one or more variations that can occur during a circuit production process. A quality-based metric is used to project a production yield for the virtual representation of the fabricated circuit. The physical layout diagram and/or the production process are modified. The obtaining, using and modifying steps are repeated until a desired projected production yield is attained. | 07-14-2011 |
20110224951 | Integrated Framework for Finite-Element Methods for Package, Device and Circuit Co-Design - Electrical finite element analysis is carried out on a circuit design, which includes devices, to determine an acceptable power-performance envelope and to obtain data for circuit temperature mapping. A circuit temperature map is developed for the circuit design, based on the data for circuit temperature mapping. Thermo-mechanical finite element analysis is carried out on a package design for the circuit design, based on the circuit temperature map, to determine a package reliability limit based on thermal stress considerations. It is determined whether the package design and the circuit design jointly satisfy: (i) power-performance conditions specified in the acceptable power-performance envelope; and (ii) the package reliability limit based on the thermal stress considerations. | 09-15-2011 |
20110313747 | Technology Computer-Aided Design (TCAD)-Based Virtual Fabrication - A single finite element mesh is generated for predicting performance of an integrated circuit design. A plurality of sample points are identified for conducting a variability study on at least one parameter associated with the integrated circuit design. The sample points are selected to predict performance of the integrated circuit design when subject to variations in the at least one parameter due to variations in manufacturing processes to be used to manufacture the integrated circuit design. A parameterized netlist is generated corresponding to each of the sample points. A technology computer aided design (TCAD, e.g., finite element) simulation is run for each of the parameterized netlists, using the single finite element mesh for each of the parameterized netlists, until convergence is achieved, to obtain, for each of the parameterized netlists, at least one metric indicative of the performance of the integrated circuit design. A predicted design yield is developed for the integrated circuit design, based on the at least one metric determined for each of the parameterized netlists. In at least some instances, an importance sampling technique is tightly integrated with the TCAD process. | 12-22-2011 |
20120205721 | Design Structure for High Density Stable Static Random Access Memory - A design structure tangibly embodied in a machine readable medium for designing, manufacturing, or testing an integrated circuit includes a plurality of bit line structures, a plurality of word line structures intersecting said plurality of bit line structures to form a plurality of cell locations, and a plurality of cells located at said plurality of cell locations, each of said cells being selectively coupled to a corresponding bit line structure under control of a corresponding word line structure, each of said cells comprising a logical storage element having at least a first n-type field effect transistor and at least a first p-type field effect transistor, wherein said at least first n-type field effect transistor is formed with a relatively thick buried oxide layer sized to reduce capacitance of said bit line structures, and said at least first p-type field effect transistor is formed with a relatively thin buried oxide layer. | 08-16-2012 |
20120290281 | TABLE-LOOKUP-BASED MODELS FOR YIELD ANALYSIS ACCELERATION - In one embodiment, the invention is a method and apparatus for table-lookup-based models for yield analysis acceleration. One embodiment of a method for statistically evaluating a design of an integrated circuit includes simulating the integrated circuit and generating a lookup table for use in the simulating, the lookup table comprising one or more blocks that specify a device element for an associated bias voltage, wherein the generating comprises generating only those of the one or more blocks that specify the device element for a bias voltage that is required during the simulating. | 11-15-2012 |
20130060551 | Technology Computer-Aided Design (TCAD)-Based Virtual Fabrication - A single finite element mesh is generated for predicting performance of an integrated circuit design. A plurality of sample points are identified for conducting a variability study on at least one parameter associated with the integrated circuit design. The sample points are selected to predict performance of the integrated circuit design when subject to variations in the at least one parameter due to variations in manufacturing processes to be used to manufacture the integrated circuit design. A parameterized netlist is generated corresponding to each of the sample points. A technology computer aided design (TCAD) simulation is run for each of the parameterized netlists, using the single finite element mesh for each of the parameterized netlists, until convergence is achieved, to obtain, for each of the parameterized netlists, at least one metric indicative of the performance of the integrated circuit design. A predicted design yield is developed for the integrated circuit design. | 03-07-2013 |
20130289948 | FET-BOUNDING FOR FAST TCAD-BASED VARIATION MODELING - A method for analyzing circuits includes identifying one or more device zones in a full device structure. The device zones provide areas of interest to be analyzed. A partial device is generated that representatively includes the one or more device zones. Analytical meshes of the partial device are reduced by employing physical characteristics of the full device structure. The partial device is simulated, using a processor, to obtain device output information in the areas of interest that is representative of the full device structure. Systems are also disclosed. | 10-31-2013 |
20130289965 | FET-BOUNDING FOR FAST TCAD-BASED VARIATION MODELING - A method for analyzing circuits includes identifying one or more device zones in a full device structure. The device zones provide areas of interest to be analyzed. A partial device is generated that representatively includes the one or more device zones. Analytical meshes of the partial device are reduced by employing physical characteristics of the full device structure. The partial device is simulated, using a processor, to obtain device output information in the areas of interest that is representative of the full device structure. Systems are also disclosed. | 10-31-2013 |