摘要:
A differential sensing content addressable memory cell without any word lines connected to the cells in the same row comprises a first bit line for supplying a first bit. A first storage element has a first phase change resistor for storing a first stored bit, which is connected in series with a first diode. The first storage element is connected to the first bit line. A second bit line supplies a second bit, with the second bit being an inverse of the first bit. A second storage element has a second phase change resistor for storing a second stored bit, which is connected in series with a second diode. The second storage element is connected to the second bit line. A match line is connected to the first and second storage elements for indicating whether a match occurred between the first bit and the first stored bit, and between the second bit and the second stored bit
摘要:
A stacked gate nonvolatile memory floating gate device has a control gate. Programming of the cell in the array is accomplished by hot channel electron injection from the drain to the floating gate. Erasure occurs by Fowler-Nordheim tunneling of electrons from the floating gate to the control gate. Finally, to increase the density, each cell can be made in a trench.
摘要:
An isolation-less, contact-less nonvolatile memory array has a plurality of memory cells each with a floating gate for the storage of charges thereon, arranged in a plurality of rows and columns. Each memory cell can be of a number of different types. All the bit lines and source lines of the various embodiments are buried and are contact-less. In a first embodiment, each cell can be represented by a stacked gate floating gate transistor coupled to a separate assist transistor. The entire array can be planar; or in a preferred embodiment each of the floating gate transistors is in a trench; or each of the assist transistors is in a trench. In a second embodiment, each cell can be represented by a stacked gate floating gate transistor with the transistor in a trench. In a third embodiment, each cell can be represented by two stacked gate floating gate transistors coupled to a separate assist transistor, positioned between the two stacked gate floating gate transistors. The entire array can be planar; or in a preferred embodiment each of the floating gate transistors is in a trench; or each of the assist transistors is in a trench. Novel methods to manufacture the arrays and methods to program, erase, and read each of these embodiments of the memory cells is disclosed.
摘要:
A non-volatile memory cell has a single crystalline semiconductive material, such as single crystalline silicon, of a first conductivity type. A first and a second region each of a second conductivity type, different from the first conductivity type, spaced apart from one another is formed in the semiconductive material. A channel region, having a first portion, and a second portion, connects the first and second regions for the conduction of charges. A dielectric is on the channel region. A floating gate, which can be conductive or non-conductive, is on the dielectric, spaced apart from the first portion of the channel region. The first portion of the channel region is adjacent to the first region, with the first floating gate having generally a triangular shape. The floating gate is formed in a cavity. A gate electrode is capacitively coupled to the first floating gate, and is spaced apart from the second portion of the channel region. The second portion of the channel region is between the first portion and the second region. A bi-directional non-volatile memory cell has two floating gates each formed in a cavity. A method of making the non-volatile memory cell and the array are also disclosed.
摘要:
An array of floating gate memory cells, and a method of making same, where each pair of memory cells includes a pair of trenches formed into a surface of a semiconductor substrate, with a strip of the substrate disposed therebetween, a source region formed in the substrate strip, a pair of drain regions, a pair of channel regions each extending between the source region and one of the drain regions, a pair of floating gates each disposed in one of the trenches, and a pair of control gates. Each channel region has a first portion disposed in the substrate strip and extending along one of the trenches, a second portion extending underneath the one trench, a third portion extending along the one trench, and a fourth portion extending along the substrate surface and under one of the control gates.
摘要:
A self aligned method of forming a semiconductor memory array of floating gate memory cells in a semiconductor substrate has a plurality of spaced apart isolation regions on the substrate substantially parallel to one another. An active region is between each pair of adjacent isolation regions. The active and isolation regions are formed in parallel and in the column direction. In the row direction, strips of spaced apart silicon nitride are formed. A source line plug is formed between adjacent pairs of silicon nitride and is in contact with a first region in the active regions, and the isolation regions. The strips of silicon nitride are removed and isotropically etched. In addition, the materials beneath the silicon nitride are also isotropically etched. Polysilicon spacers are then formed in the row direction parallel to the source line plug and adjacent to the floating gates. A second region is formed between adjacent, spaced apart, control gates. A bit line is formed in the bit line direction contacting the second region in the space between the control gates.
摘要:
A self aligned method of forming a semiconductor memory array of floating gate memory cells in a semiconductor substrate has a plurality of spaced apart isolation regions on the substrate substantially parallel to one another. An active region is between each pair of adjacent isolation regions. The active and isolation regions are formed in parallel and in the column direction. In the row direction, strips of spaced apart silicon nitride are formed. A source line plug is formed between adjacent pairs of silicon nitride and is in contact with a first region in the active regions, and the isolation regions. The strips of silicon nitride are removed and isotropically etched. In addition, the materials beneath the silicon nitride are also isotropically etched. Polysilicon spacers are then formed in the row direction parallel to the source line plug and adjacent to the floating gates to form connected control gates. A second region is formed between adjacent, spaced apart, control gates. A bit line is formed in the bit line direction contacting the second region in the space between the control gates.
摘要:
A system for improving the management and usage of blocks based on intrinsic endurance may be used to improve memory usage for flash memory, such as a memory card. The overall card endurance may be extended by cycling blocks with higher intrinsic endurance over the lowest endurance target of the worst block. This may be accomplished by managing blocks with different intrinsic endurance values internally or by partitioning the blocks with different intrinsic endurance values externally for different usage.
摘要:
A storage module may include a NAND-type flash memory array and one or more controllers configured to increase gate bias voltage levels applied to gates in the memory array to overcome possible gate shorts and recover data identified as being uncorrectable. The increased gate bias voltages may be applied to gates of a single type of transistor or to different types of transistors in the memory array, including drain select transistors, source select transistors, or floating gate transistors.
摘要:
A method and system have been described for counteracting and correcting for read disturb effects in blocks of flash memory. The method may include the step of a controller of the memory system performing a read scrub scan on only a portion of one targeted word line in a block at desired intervals. The controller may calculate whether a read scrub scan is necessary based on a probabilistic determination that is calculated in response to each received host read command. The controller may then place a block associated with the targeted word line into a refresh queue if a number of errors are detected in the targeted word line that meets or exceeds a predetermined threshold. The block refresh process may include copying the data from the block into a new block during a background operation.