Abstract: Nonvolatile memory devices include a first NAND-type string of EEPROM cells having a first plurality of string selection transistors therein electrically connected in series within the string. This first plurality of string selection transistors includes a first plurality of depletion-mode transistors and a first enhancement-mode transistor. A second NAND-type string of EEPROM cells is provided with a second plurality of string selection transistors therein that are electrically connected in series. The second plurality of string selection transistors includes a second plurality of depletion-mode transistors and a second enhancement-mode transistor. The first enhancement-mode transistor is stacked vertically relative to one of the second plurality of depletion-mode transistors and the second enhancement-mode transistor is stacked vertically relative to one of the first plurality of depletion-mode transistors.

Abstract: A gate structure of a non-volatile memory device and a method of forming the same including a tunnel oxide layer pattern, a charge trap layer pattern, a blocking dielectric layer pattern having the uppermost layer including a material having a first dielectric constant greater than that of a material included in the tunnel oxide layer pattern, and first and second conductive layer patterns. The gate structure includes a first spacer to cover at least the sidewall of the second conductive layer pattern. The gate structure includes a second spacer covering the sidewall of the first spacer and the sidewall of the first conductive layer pattern and including a material having a second dielectric constant equal to or greater than the first dielectric constant. In the non-volatile memory device including the gate structure, erase saturation caused by back tunneling is reduced.

Abstract: In method of programming a nonvolatile memory device including first and second cell strings that are coupled to one bitline, a first channel of the first cell string and a second channel of the second cell string are precharged by applying a first voltage to the bitline, one cell string is selected from the first and second cell strings, and a memory cell included in the selected cell string is programmed by applying a second voltage greater than a ground voltage and less than the first voltage to the bitline.

Abstract: In a method of manufacturing a semiconductor device, a dielectric layer structure and a control gate layer can be formed sequentially on a substrate. The control gate layer can be partially etched to form a plurality of control gates. A gate spacer and a sacrificial spacer sequentially can be stacked on a sidewall of the control gate and on a portion of the dielectric layer structure. The dielectric layer structure can be partially etched using the sacrificial spacer and the gate spacer as an etching mask to form a plurality of dielectric layer structure patterns. The sacrificial spacer can be removed. An insulating interlayer can be formed on the substrate to form an air gap. The insulating interlayer can cover the dielectric layer structure pattern, the gate spacer and the control gate. The air gap can extend between the adjacent gate spacers and between the adjacent dielectric layer structure patterns.

Abstract: A semiconductor device and a method of fabricating the same are provided. The semiconductor device includes a first dielectric pattern, a data storage pattern and a second dielectric pattern, which are sequentially stacked on a semiconductor substrate. A first conductive pattern is provided on the second dielectric pattern. A second conductive pattern having a greater width than the first conductive pattern is provided on the first conductive pattern.

Abstract: In a semiconductor device and a method of forming such a device, the semiconductor device comprises a substrate of semiconductor material extending in a horizontal direction. A plurality of interlayer dielectric layers is provided on the substrate. A plurality of gate patterns is provided, each gate pattern between a neighboring lower interlayer dielectric layer and a neighboring upper interlayer dielectric layer. A vertical channel of semiconductor material extends in a vertical direction through the plurality of interlayer dielectric layers and the plurality of gate patterns, a gate insulating layer between each gate pattern and the vertical channel that insulates the gate pattern from the vertical channel, the vertical channel being in contact with the substrate at a contact region that comprises a semiconducting region.

Abstract: A flash memory device provided here comprises a user data area storing user data; and a security data area storing security data. The security data area stores a security data pattern in which first groups of memory cells storing security data are arranged respectively between second groups of memory cells storing dummy data.

Abstract: A flash memory device, including a cell array region where a plurality of memory cells are connected in series to a single cell string, the cell array region including a pocket p-well configured to accommodate the plurality of memory cells and an n-well configured to surround the pocket p-well, a first peripheral region where low-voltage (LV) and high-voltage (HV) switches are connected to the memory cells through a word line, and a second peripheral region where bulk voltage switches are connected to bulk regions of the LV and HV switches.

Abstract: A semiconductor device includes a substrate of semiconductor material extending in a horizontal direction. A plurality of interlayer dielectric layers are provided on the substrate. A plurality of gate patterns are provided, each gate pattern being between a neighboring lower interlayer dielectric layer and a neighboring upper interlayer dielectric layer. A vertical channel of semiconductor material extends in a vertical direction through the plurality of interlayer dielectric layers and the plurality of gate patterns, a gate insulating layer between each gate pattern and the vertical channel that insulates the gate pattern from the vertical channel, the vertical channel being in contact with the substrate at a contact region that comprises a semiconducting region.

Abstract: Nonvolatile memory devices include a plurality of nonvolatile memory cell transistors having respective channel regions within a semiconductor layer formed of a first semiconductor material and respective source/drain regions formed of a second semiconductor material, which has a smaller bandgap relative to the first semiconductor material. The source/drain regions can form non-rectifying junctions with the channel regions. The source/drain regions may include germanium (e.g., Ge or SiGe regions), the semiconductor layer may be a P-type silicon layer and the source/drain regions of the plurality of nonvolatile memory cell transistors may be P-type germanium or P-type silicon germanium.

Abstract: A programming method of a semiconductor memory device includes charging a channel of an inhibit string to a precharge voltage provided to the common source line and boosting the charged channel by providing a wordline voltage to the cell strings. The inhibit string is connected to a program bitline among the bitlines.

Abstract: NAND flash memory device includes a common bit line, a first cell string including a first string selecting transistor having a first gate length, a second string selecting transistor having a second gate length, first cell transistors each having a third gate length and a first ground selecting transistor having a fourth gate length, a second cell string including a third string selecting transistor having the first gate length, a fourth string selecting transistor having the second gate length, second cell transistors each having the third gate length and a second ground selecting transistor having the fourth gate length and a common source line commonly connected to end portions of the first and second ground selecting transistors included in the first and second cell strings. At least one of the first gate length and the second gate length is smaller than the fourth gate length.

Abstract: A gate pattern is disclosed that includes a semiconductor substrate, a lower conductive pattern, an upper conductive pattern, and a sidewall conductive pattern. The lower conductive pattern is on the substrate. The insulating pattern is on the lower conductive pattern. The upper conductive pattern is on the insulating pattern opposite to the lower conductive pattern. The sidewall conductive pattern is on at least a portion of sidewalls of the upper conductive pattern and the lower conductive pattern. The sidewall conductive pattern electrically connects the upper conductive pattern and the lower conductive pattern. An upper edge portion of the lower conductive pattern may be recessed relative to a lower edge portion of the lower conductive pattern to define a ledge thereon. The sidewall conductive pattern may be directly on the ledge and sidewall of the recessed upper edge portion of the lower conductive pattern.

Abstract: A nonvolatile memory including a plurality of memory transistors in series, wherein source/drain and channel regions therebetween are of a first type and a select transistor, at each end of the plurality of memory transistors in series, wherein channels regions of each of the select transistors is of the first type. The first type may be n-type or p-type. The nonvolatile memory may further include a first dummy select transistor at one end of the plurality of memory transistors in series between one of the select transistors and the plurality of memory transistors in series and a second dummy select transistor at the other end of the plurality of memory transistors in series between the other select transistor and the plurality of memory transistors in series.

Abstract: Flash memory devices include a pair of elongated, closely spaced-apart main active regions in a substrate. A sub active region is also provided in the substrate, extending between the pair of elongated, closely spaced-apart main active regions. A bit line contact plug is provided on, and electrically contacting, the sub active region and being at least as wide as the sub active region. An elongated bit line is provided on, and electrically contacting, the bit line contact plug remote from the sub active region.

Abstract: A semiconductor device includes a semiconductor substrate including at least one memory channel region and at least one memory source/drain region, the memory channel region and the memory source/drain region being arranged alternately, and at least one word line on the memory channel region, wherein the memory source/drain region has a higher net impurity concentration than the memory channel region.

Abstract: Integrated circuit flash memory devices, such as NAND flash memory devices, include an array of regular flash memory cells, an array of dummy flash memory cells and an erase controller. The erase controller is configured to concurrently apply a different predetermined bias voltage to the dummy flash memory cells than to the regular flash memory cells during an erase operation of the integrated circuit flash memory device. Related methods are also described.

Abstract: A non-volatile memory device includes an array of non-volatile memory cells configured to support single bit and multi-bit programming states. A control circuit is provided, which is configured to program a first page of non-volatile memory cells in the array as M-bit cells during a first programming operation and further configured to program the first page of non-volatile memory cells as N-bit cells during a second programming operation. The first and second programming operations are separated in time by at least one operation to erase the first page of non-volatile memory cells. M and N are unequal integers greater than zero.

Abstract: Non-volatile memory devices are provided including a control gate electrode on a substrate; a charge storage insulation layer between the control gate electrode and the substrate; a tunnel insulation layer between the charge storage insulation layer and the substrate; a blocking insulation layer between the charge storage insulation layer and the control gate electrode; and a material layer between the tunnel insulation layer and the blocking insulation layer, the material layer having an energy level constituting a bottom of a potential well.

Abstract: A semiconductor device includes an active region defined in a semiconductor substrate, and gate electrodes crossing over the active region. Source/drain regions are defined in the active region on two sides of the gate electrode. At least one of the source/drain regions is a field effect source/drain region generated by a fringe field of the gate. The other source/drain region is a PN-junction source/drain region having different impurity fields and different conductivity than the substrate. At least one of the source/drain regions is a field effect source/drain region. Accordingly, a short channel effect is reduced or eliminated in the device.