Patent application number | Description | Published |
20080278999 | SOURCE AND DRAIN SIDE EARLY BOOSTING USING LOCAL SELF BOOSTING FOR NON-VOLATILE STORAGE - Program disturb is reduced during programming of non-volatile storage by providing a boosting scheme in which isolation voltage are applied to two word lines to create a source side channel region on a source side of one isolation word line, an intermediate channel region between the isolation word lines and a drain side channel region on a drain side of the other isolation word line. Further, during a programming operation, the source and drain side channel regions are boosted early while the intermediate channel region is boosted later, when a program pulse is applied. This approach prevents charge leakage from the intermediate channel region to the source side, avoiding disturb of already programmed storage elements, while also allowing electrons to flow from the intermediate channel region to the drain side channel region, which makes the boosting of the intermediate channel region easier. | 11-13-2008 |
20080279007 | BOOSTING FOR NON-VOLATILE STORAGE USING CHANNEL ISOLATION SWITCHING - Program disturb is reduced in non-volatile storage by preventing source side boosting in selected NAND strings. A self-boosting mode which includes an isolation word line is used. A channel area of an inhibited NAND string is boosted on a source side of the isolation word line before the channel is boosted on a drain side of the isolation word line. Further, storage elements near the isolation word line are kept in a conducting state during the source side boosting so that the source side channel is connected to the drain side channel. In this way, in selected NAND strings, source side boosting can not occur and thus program disturb due to source side boosting can be prevented. After the source side boosting, the source side channel is isolated from the drain side channel, and drain side boosting is performed. | 11-13-2008 |
20080279008 | NON-VOLATILE STORAGE WITH BOOSTING USING CHANNEL ISOLATION SWITCHING - Non-volatile storage in which program disturb is reduced by preventing source side boosting in selected NAND strings. A self-boosting mode which includes an isolation word line is used. A channel area of an inhibited NAND string is boosted on a source side of the isolation word line before the channel is boosted on a drain side of the isolation word line. Further, storage elements near the isolation word line are kept in a conducting state during the source side boosting so that the source side channel is connected to the drain side channel. In this way, in selected NAND strings, source side boosting can not occur and thus program disturb due to source side boosting can be prevented. After the source side boosting, the source side channel is isolated from the drain side channel, and drain side boosting is performed. | 11-13-2008 |
20080291735 | METHOD FOR USING TRANSITIONAL VOLTAGE DURING PROGRAMMING OF NON-VOLATILE STORAGE - To program one or more non-volatile storage elements, a set of programming pulses are applied to at least one selected non-volatile storage element and one or more particular unselected non-volatile storage elements, for example, via a common word line. A boosting voltage is applied to other unselected non-volatile storage elements during the programming process in order to boost the channels of the unselected non-volatile storage elements so that programming will be inhibited. Each of the programming pulses has a first intermediate magnitude, a second intermediate magnitude and a third magnitude. In one embodiment, the first intermediate magnitude is similar to or the same as the boosting voltage. The second intermediate magnitude is greater than the first intermediate magnitude, but less then the third magnitude. Such an arrangement can reduce the effects of program disturb. | 11-27-2008 |
20080291736 | NON-VOLATILE STORAGE SYSTEM WITH TRANSITIONAL VOLTAGE DURING PROGRAMMING - To program one or more non-volatile storage elements, a set of programming pulses are applied to at least one selected non-volatile storage element and one or more particular unselected non-volatile storage elements, for example, via a common word line. A boosting voltage is applied to other unselected non-volatile storage elements during the programming process in order to boost the channels of the unselected non-volatile storage elements so that programming will be inhibited. Each of the programming pulses has a first intermediate magnitude, a second intermediate magnitude and a third magnitude. In one embodiment, the first intermediate magnitude is similar to or the same as the boosting voltage. The second intermediate magnitude is greater than the first intermediate magnitude, but less then the third magnitude. Such an arrangement can reduce the effects of program disturb. | 11-27-2008 |
20090010065 | NON-VOLATILE MEMORY USING MULTIPLE BOOSTING MODES FOR REDUCED PROGRAM DISTURB - A non-volatile storage system which reduces program disturb. Multiple boosting modes are implemented while programming non-volatile storage. For example, self-boosting, local self-boosting, erased area self-boosting and revised erased area self-boosting may be used. One or more switching criteria are used to determine when to switch to a different boosting mode. The boosting mode may be used to prevent program disturb in unselected NAND strings while storage elements are being programmed in selected NAND strings. By switching boosting modes, an optimal boosting mode can be used as conditions change. The boosting mode can be switched based on various criteria such as program pulse number, program pulse amplitude, program pass number, the position of a selected word line, whether coarse or fine programming is used, whether a storage element reaches a program condition and/or a number of program cycles of the non-volatile storage device. | 01-08-2009 |
20090290429 | ENHANCED BIT-LINE PRE-CHARGE SCHEME FOR INCREASING CHANNEL BOOSTING IN NON-VOLATILE STORAGE - Channel boosting is improved in non-volatile storage to reduce program disturb. A pre-charge module voltage source is used to pre-charge bit lines during a programming operation. The pre-charge module voltage source is coupled to a substrate channel via the bit lines to boost the channel. An additional source of boosting is provided by electromagnetically coupling a voltage from a conductive element to the bit lines and the channel. To achieve this, the bit lines and the channel are allowed to float together by disconnecting the bit lines from the voltage sources. The conductive element can be a source line, power supply line or substrate body, for instance, which receives an increasing voltage during the pre-charging and is proximate to the bit lines. | 11-26-2009 |
20090323429 | PROGRAMMING ALGORITHM TO REDUCE DISTURB WITH MINIMAL EXTRA TIME PENALTY - Programming time is reduced in a non-volatile memory in a multi-pass programming process. In a first programming pass, high state cells are programmed by a sequence of program pulses to identify fast and slow high state cells, while lower state cells are locked out from programming. Once identified, the fast high state cells are temporarily locked out from programming while the slow high state cells continue being programmed to their final intended state. Further, the program pulses are sharply stepped up to program the slow high state cells. In a second programming pass, the fast high state cells are programmed along with the other, lower state cells, until they all reach their respective intended states. A time savings is realized compared to approaches in which all high state cells are programmed in the first programming pass. | 12-31-2009 |