Abstract: Disclosed is a DRAM circuit that incorporates an improved reference cell, has half the capacitance of the memory cell, does not require a particular reference voltage, and can be formed using the same fabrication processes as the memory cell. This DRAM circuit comprises a memory cell with a single trench capacitor and a reference cell having two trench capacitors. The two reference cell trench capacitors are connected in series through a merged buried capacitor plate such that they provide half the capacitance of the memory cell trench capacitor. Additionally, the reference cell trench capacitors have essentially the same structure as the memory cell trench capacitor so that they can be formed in conjunction with the memory cell trench capacitor. Also disclosed are a design structure for the above-described memory circuit and a method for forming the above-described memory circuit.

Abstract: A method of forming an integrated circuit comprises: providing a semiconductor topography comprising an active transistor laterally adjacent to a trench capacitor formed in a semiconductor substrate, the active transistor comprising a source junction and a drain junction, wherein a barrier layer is disposed along a periphery of the trench capacitor for isolating the trench capacitor; forming an interlevel dielectric across the semiconductor topography; concurrently etching (i) a first opening through the interlevel dielectric to the drain junction of the active transistor and the trench capacitor, and (ii) a second opening through the interlevel dielectric to the source junction of the active transistor; and filling the first opening and the second opening with a conductive material to form a strap for electrically connecting the trench capacitor to the drain junction of the active transistor and to also form a contact for electrically connecting the source junction to an overlying level of the integrated cir

Abstract: A system to generate a reference for a charge pump may include a diode-connected transistor providing a reference voltage, and an output transistor. The system may also include a reference circuit to provide a current that is substantially temperature insensitive and the reference circuit delivers the current across the diode-connected transistor thereby enabling the reference voltage to move with processing of the diode-connected transistor.

Abstract: A system to evaluate charge pump output may include a comparator to compare a charge pump output voltage to a reference voltage to generate a comparison result. The system may also include a divider to divide down a clock signal. The system may further include a logical conjunction unit to operate on the comparison result and the divided down clock signal.

Abstract: Disclosed is a DRAM circuit that incorporates an improved reference cell, has half the capacitance of the memory cell, does not require a particular reference voltage, and can be formed using the same fabrication processes as the memory cell. This DRAM circuit comprises a memory cell with a single trench capacitor and a reference cell having two trench capacitors. The two reference cell trench capacitors are connected in series through a merged buried capacitor plate such that they provide half the capacitance of the memory cell trench capacitor. Additionally, the reference cell trench capacitors have essentially the same structure as the memory cell trench capacitor so that they can be formed in conjunction with the memory cell trench capacitor. Also disclosed are a design structure for the above-described memory circuit and a method for forming the above-described memory circuit.

Abstract: A deep trench containing a doped semiconductor fill portion having a first conductivity type doping and surrounded by a buried plate layer having a second conductivity type doping at a lower portion is formed in a semiconductor layer having a doping of the first conductivity type. A doped well of the second conductivity type abutting the buried plate layer is formed. The doped semiconductor fill portion functions as a temporary reservoir for electrical charges of the first conductivity type that are generated by a radiation particle, and the buried plate layer functions as a temporary reservoir for electrical charges of the second conductivity type. The buried plate layer and the doped semiconductor fill portion forms a capacitor, and provides protection from soft errors to devices formed in the semiconductor layer or the doped well.

Abstract: An embedded DRAM (eDRAM) having multi-use refresh cycles is described. In one embodiment, there is a multi-level cache memory system that comprises a pending write queue configured to receive pending prefetch operations from at least one of the levels of cache. A prefetch queue is configured to receive prefetch operations for at least one of the levels of cache. A refresh controller is configured to determine addresses within each level of cache that are due for a refresh. The refresh controller is configured to assert a refresh write-in signal to write data supplied from the pending write queue specified for an address due for a refresh rather than refresh existing data. The refresh controller asserts the refresh write-in signal in response to a determination that there is pending data to supply to the address specified to have the refresh.

Abstract: A design structure for an embedded DRAM (eDRAM) having multi-use refresh cycles is described. In one embodiment, there is a multi-level cache memory system that comprises a pending write queue configured to receive pending prefetch operations from at least one of the levels of cache. A prefetch queue is configured to receive prefetch operations for at least one of the levels of cache. A refresh controller is configured to determine addresses within each level of cache that are due for a refresh. The refresh controller is configured to assert a refresh write-in signal to write data supplied from the pending write queue specified for an address due for a refresh rather than refresh existing data. The refresh controller asserts the refresh write-in signal in response to a determination that there is pending data to supply to the address specified to have the refresh.

Abstract: Disclosed is design structure including an integrated circuit having a system for moving a failing address into a new FAR by utilizing the functional compare circuitry during BIST of redundant memory elements. Disclosed is an any-for-any scheme that eliminates the tri-state address bus. The design structure allows for easy, discrete scaling with the addition of more FARs, while also allowing larger addresses with no additional control circuit overhead.

Abstract: An integrated circuit having an integrated circuit and method for moving a failing address into a next available FAR by utilizing the functional compare circuitry during BIST of redundant memory elements. A method of is disclosed that includes: providing a set of FARs and an associated set of redundant elements, wherein each FAR maps to a corresponding redundant element; testing a set of elements and placing an address of each failing element into a FAR; testing each redundant element and marking a FAR as bad when a redundant element corresponding to the FAR fails; and readdressing the set of elements and placing an address of an element being readdressed in a new FAR when the address of the element being readdressed matches an address in a FAR that has been marked as bad.

Abstract: A design structure embodied in a machine readable medium used in a design process includes a cache structure having a cache tag array associated with a eDRAM data cache comprising a plurality of cache lines, the cache tag array having an address tag, a valid bit and an access bit corresponding to each of the plurality of cache lines; and each access bit configured to indicate whether the corresponding cache line has been accessed as a result of a read or a write operation during a defined assessment period, which is smaller than retention time of data in the DRAM data cache; wherein, for any of the cache lines not accessed as a result of a read or a write operation during the defined assessment period, the individual valid bit associated therewith is set to a logic state that indicates the data in the associated cache line is invalid.

Abstract: An apparatus for implementing a refreshless, embedded dynamic random access memory (eDRAM) cache device includes a cache structure having a cache tag array associated with a DRAM data cache with a plurality of cache lines, the cache tag array having an address tag, a valid bit and an access bit corresponding to each of the plurality of cache lines; and each access bit configured to indicate whether the corresponding cache line has been accessed as a result of a read or a write operation during a defined assessment period, the defined assessment period being smaller than retention time of data in the DRAM data cache. For any of the cache lines that have not been accessed during the defined assessment period, the individual valid bit associated therewith is set to a logic state that indicates the data in the associated cache line is invalid.

Abstract: A method for implementing dynamic refresh protocols for DRAM based cache includes partitioning a DRAM cache into a refreshable portion and a non-refreshable portion, and assigning incoming individual cache lines to one of the refreshable portion and the non-refreshable portion of the cache based on a usage history of the cache lines. Cache lines corresponding to data having a usage history below a defined frequency are assigned to the refreshable portion of the cache, and cache lines corresponding to data having a usage history at or above the defined frequency are assigned to the non-refreshable portion of the cache.

Abstract: A design structure embodied in a machine readable medium used in a design process includes a tri-state power gating apparatus for reducing leakage current in a memory array. The apparatus includes a first distributed header device coupled to the memory array, the first distributed header device is configured for limiting leakage current through the memory array; and a header driver operatively coupled to the first distributed header device for enabling tri-state operation of the first distributed header device, wherein tri-state operation includes sleep mode, wake mode, and retention mode.

Abstract: A method for reducing leakage current in a memory array comprising: coupling a first distributed header device to the memory array, the first distributed header device is configured for limiting leakage current through the memory array; and coupling a header driver operatively to the first distributed header device for enabling tri-state operation of the first distributed header device, wherein tri-state operation includes sleep mode, wake mode, and retention mode.

Abstract: A tri-state power gating apparatus for reducing leakage current in a memory array includes a first distributed header device coupled to the memory array, the first distributed header device is configured for limiting leakage current through the memory array; and a header driver operatively coupled to the first distributed header device for enabling tri-state operation of the first distributed header device, wherein tri-state operation includes sleep mode, wake mode, and retention mode.

Abstract: A circuit for accessing a memory cell includes a local bitline and a local sense amplifier having a plurality of transistors. The local bitline may be connect the memory cell and the sense amplifier. A first global bitline may be connected to a first one of the plurality of transistors. A second global bitline may be connected to a second one of the plurality of transistors. A secondary sense amplifier may be connected to the first and second global bitlines.

Abstract: Dynamic random access memory (DRAM) sensing is accomplished by using capacitive mismatch between a bit line without a cell and a corresponding bit line with a cell to determine if a selected capacitor holds a one or a zero. Isolators on the bit lines are used to create the mismatch. In this manner, reference cells and bit-line twisting are eliminated, while maintaining rail pre-charge at VDD or ground. Utilizing short bit-lines, ‘Zero’ (for GND pre-charge) can be sensed by means of inherent capacitive mis-match. The zero will hold the bit-line at GND, the bit-line without a cell (or with fewer cells) will have less capacitance and rise faster than the bit-line with the cell due to capacitive mis-match. For sensing a ‘one’, the bit-line will have enough signal to overcome the capacitive mis-match.

Abstract: A method and circuit design for enabling both shift path and scan path functionality with a single port LSSD latch designed for scan path functionality only, without increasing the device's internal real estate and without substantial increase in overall device real estate. The circuit design eliminates the need for additional logic components to be built into the internal circuitry of the device and also eliminates the cost of providing dual port LSSD latches within the device. Implementation of the invention involves providing a unique configuration of low level logic components as input circuitry that is coupled to a pair of single port LSSD latches that operate as the input latches for the device. The low level logic components accomplishes the splitting of scan chain inputs and shift chain inputs to the input latches and thus enables the single ported LSSD latches to operate with similar functionality as dual ported LSSD latches.

Abstract: A novel trench-type decoupling capacitor structure and low-cost manufacturing process to create trench decoupling capacitors (decaps). In a unique aspect, the invention necessitates the addition of only a simplified trench to a base logic design.