摘要:
According to an aspect of the embodiments, the block decoder control circuits which drive the pass transistors for the word lines for a flash memory array are driven with a control voltage that is regulated to be one enhancement transistors threshold voltage higher than the highest voltage that is actually driven onto the word lines. According to another aspect of some of the embodiments, the block decoder control circuits are implemented with transistors having a very low threshold voltage. According to yet another aspect of some of the embodiments, a special series connection is used to prevent any leakage current through the block decoder control circuit from the high voltage generating charge pumps which might otherwise result from the use of low threshold voltage transistors. In the special series connection, any leakage current occurs from the supply voltage source rather than from the high voltage generating charge pumps. According to still another aspect of some of the embodiments, a special gate connection applies an intermediate bias voltage higher than a positive supply voltage onto the gates of the unselected block decoder transistors that are connected to a high-voltage. Several embodiments are presented which combine the regulated control voltage aspect and various combinations of the other aspects.
摘要:
According to an aspect of the embodiments, the block decoder control circuits which drive the pass transistors for the word lines for a flash memory array are driven with a control voltage that is regulated to be one enhancement transistor's threshold voltage higher than the highest voltage that is actually driven onto the word lines. According to another aspect of some of the embodiments, the block decoder control circuits are implemented with transistors having a very low threshold voltage. According to yet another aspect of some of the embodiments, a special series connection is used to prevent any leakage current through the block decoder control circuit from the high voltage generating charge pumps which might otherwise result from the use of low threshold voltage transistors. In the special series connection, any leakage current occurs from the supply voltage source rather than from the high voltage generating charge pumps. According to still another aspect of some of the embodiments, a special gate connection applies an intermediate bias voltage higher than a positive supply voltage onto the gates of the unselected block decoder transistors that are connected to a high-voltage. Several embodiments are presented which combine the regulated control voltage aspect and various combinations of the other aspects.
摘要:
An integrated circuit (IC) device may include a first portion having a plurality of volatile memory cells; and a second portion coupled by a data transfer path to the first portion, the second portion including a plurality of nonvolatile memory cells, each nonvolatile memory cell including at least one resistive element programmable more than once between different resistance values. A memory device may also include variable impedance elements accessible by access bipolar junction transistors (BJTs) having at least a portion formed by a semiconductor layer formed over a substrate. A memory device may also include a plurality of memory elements that each includes a dielectric layer formed between a first and second electrode, the dielectric layer including a solid electrolyte with a soluble metal having a mobility less than that of silver in a germanium disulfide.
摘要:
A memory device may include a plurality of memory cells each having elements with at least one solid ion conductor programmable between at least two different impedance states for at least two different data retention times, the plurality of memory cells being dividable into a plurality of portions, each portion being separately configurable for one of the data retention times.
摘要:
An integrated circuit may include a plurality of sub bit line groups, each sub bit line group coupled to a different main bit line by a corresponding access device; and a plurality of programmable impedance elements arranged into element groups, each element group being coupled to a corresponding each sub bit line.
摘要:
A high voltage transistor exhibiting low leakage and low body effect is formed while avoiding an excessive number of costly masking steps. Embodiments include providing a field implant blocking mask over the channel area, thereby producing a transistor with low body effect, the field implant blocking mask having appropriate openings so that the field implant occurs at the edges of the channel, thereby reducing leakage.
摘要:
A high voltage transistor exhibiting high gated diode breakdown voltage is formed while avoiding an excessive number of costly masking steps. Embodiments include providing a high gated diode breakdown voltage by masking the high voltage junctions from the conventional field implant, masking the source/drain regions from the conventional threshold adjust implant, providing a thick gate oxide layer, employing a very lightly doped n-type implant in lieu of conventional n+ and LDD implants, and forming contacts to the source and drain regions at a minimum distance from the gate.
摘要:
A high voltage transistor exhibiting high gated diode breakdown voltage, low leakage and low body effect is forced while avoiding an excessive number of costly masking steps. Embodiments include providing a high gated diode breakdown voltage by masking the high voltage junctions from the conventional field implant, masking the source/drain regions from the conventional threshold adjust implant, and employing a very lightly doped n-type implant in lieu of conventional n+ and LDD implants. Appropriate openings are formed in the field implant blocking mask so that the field implant occurs at the edges of the junctions, thus achieving low leakage. The field implant blocking mask is extended over the channel area, thereby producing a transistor with low body effect.
摘要:
A system and methodology is provided for programming first and second bits of a memory array of dual bit memory cells at a substantially high delta VT. The substantially higher VT assures that the memory array will maintain programmed data and erase data consistently after higher temperature stresses and/or customer operation over substantial periods of time. At a substantially higher delta VT, programming of the first bit of the memory cell causes the second bit to program harder and faster due to the shorter channel length. Therefore, the present invention employs selected gate and drain voltages and programming pulse widths during programming of the first and second bit that assures a controlled first bit VT and slows down programming of the second bit. Furthermore, the selected programming parameters keep the programming times short without degrading charge loss.
摘要:
An erase operation is performed on a non-volatile memory cell with an oxide-nitride-oxide structure by using a negative gate erase voltage during an erase procedure to improve the speed and performance of the non-volatile memory cell after many program-erase cycles. During the erase procedure, an erase cycle is applied followed by a read cycle until the cell has a threshold erased below a desired value. For the initial erase cycle in the procedure, an initial negative gate voltage is applied. In subsequent erase cycles, a sequentially decreasing negative gate voltage is applied until the threshold is reduced below the desired value. In one embodiment, after erase is complete, the last negative gate voltage value applied is stored in a separate memory. After a subsequent programming when the erase procedure is again applied, the initial negative gate voltage applied is the negative gate voltage value for the cell stored in memory.