Abstract: A method of forming a memory device, where a first insulator layer and a charge trapping layer may be formed on a substrate, and at least one of the first insulator layer and charge trapping layer may be patterned to form patterned areas. A second insulation layer and a conductive layer may be formed on the patterned areas, and one or more of the conductive layer, second insulator layer, charge trapping layer and first insulator layer may be patterned to form a string selection line, ground selection line, a plurality of word lines between the string selection and ground selection lines on the substrate, a low voltage gate electrode, and a plurality of insulators of varying thickness. The formed memory device may be a NAND-type non-volatile memory device having a SONOS gate structure, for example.

Abstract: A nonvolatile memory device includes a semiconductor wall having an inclination angle and a gate electrode covered with the semiconductor wall. A pair of buried diffusion layers may be formed at a lower surface and upper surface formed by the semiconductor wall. A charge trap insulating layer may be sandwiched between the gate electrode and the semiconductor wall. The semiconductor wall between the buried diffusion layers may correspond to a channel of the memory device. In a method of fabricating the memory device, a pattern having a sidewall may be formed on a semiconductor substrate. A buried oxide layer may be formed at the upper surface and another buried oxide layer may be formed at the lower surface. A charge trap insulating layer may be formed at the sidewall where the buried oxide layers are formed. A gate electrode may be formed on the charge trap insulating layer. A semiconductor substrate may be formed to form a trench, so that the sidewall may be obtained.

Abstract: Two-bit programmable nonvolatile memory devices and methods of operating and fabricating the same are provided. The device comprises a plurality of device isolation layers, a plurality of word lines crossing over the device isolation layers, and a multiple insulation layer intervened between the word line and the active region. The multiple insulation layer includes a charge trap insulation layer. A source/drain region is formed at each region defined by adjacent word lines and the adjacent device isolation layers. The source/drain regions have the same surface area. A write operation of the device comprises applying a first level voltage, a ground voltage, and a write voltage to one bit line, another bit line, and a selected word line, thereby writing data into a charge trap insulation layer. By changing the voltages applied to the bit lines, 2 bits may be stored in one memory cell.

Abstract: This disclosure provides cells of nonvolatile memory devices with floating gates and methods for fabricating the same. The cell of the nonvolatile memory device includes device isolation layers in parallel with each other on a predetermined region of a semiconductor substrate that define a plurality of active regions. Each device isolation layer has sidewalls that project over the semiconductor substrate. A plurality of word lines crosses over the device isolation layers. A tunnel oxide layer, a floating gate, a gate interlayer dielectric layer, and a control gate electrode are sequentially stacked between each active region and each word line. The floating gate and the control gate electrode have sidewalls that are self-aligned to the adjacent device isolation layers.

Abstract: A method for programming a NAND-type flash memory device is provided. In the method for programming a NAND-type flash memory device having a plurality of strings two dimensionally arranged on the bulk area of a first conductivity type and a plurality of bitlines arranged in parallel on the plurality of strings, a bulk bias corresponding to a reverse bias is applied to the bulk area of the first conductivity type. At least one bitline is selected among the plurality of bitlines. At least one string is selected from among the plurality of strings connected to the selected bitline in parallel. At least one cell is programmed from among the plurality of cells within the selected strings.

Abstract: A non-volatile memory device including a cell array region formed having a plurality of parallel bit lines, a plurality of parallel word lines, a plurality of memory cells, and a plurality of common source lines, the plurality of bit lines being orthogonal to the plurality of word lines, each of the memory cells being connected to a bit line and a word line and having a stacked gate comprised of a floating gate and a control gate and a source/drain region, the plurality of common source lines being parallel to the plurality of bit lines. The non-volatile memory device also includes a peripheral circuit region for driving the memory cells in the cell array region is formed. The cell array region includes one or more bulk bias contact structures for maintaining the voltage of a bulk region in which the cell array region is formed, at or below a predetermined voltage.

Abstract: A nonvolatile memory device having a lightly doped source and a method for manufacturing the same are provided. In the nonvolatile memory device, a first insulating layer, a floating gate, a second insulating layer and a control gate are sequentially formed on a semiconductor substrate, and a drain, a lightly doped source and a highly doped source are formed around a surface of the semiconductor substrate. At this time, the highly doped source is shallower than the drain without being overlapped by the floating gate. Thus, the integration of the memory cell can be increased, and the trapping of electrons is reduced in the first insulating layer formed between the floating gate and the lightly doped source, to thereby enhance the characteristics of the memory cell.

Abstract: A method of programming a NAND-type flash memory device having bitlines and wordlines, and memory strings composed of memory cells serially connected between string select transistors coupled to each of the bitlines and ground select transistors coupled to a source line. The method comprises of applying a first voltage to one or more unselected wordlines, then applying a predetermined bitline voltage to an unselected bitline, and then applying a second voltage to the unselected wordlines, and concurrently applying a third voltage to a selected one out of the wordlines. Thus, a program disturbance phenomenon can be prevented.

Abstract: Flash type programmable nonvolatile memory unit cells are provided, along with a manufacturing method. Each unit cell is formed such that the interpoly dielectric layer and the control gate surround the top surface and also the four lateral surfaces of the floating gate. This increases the capacitance between the floating gate and the control gate, which improves a coupling ratio. This also improves electromagnetic shielding within each cell, which reduces cross talk between neighboring cells, and permits more dense integration.

Abstract: A CMOS device which includes first and second wells formed in first and second regions of a semiconductor substrate, respectively, first and second transistors formed in the respective wells, a third transistor formed in a third region of the semiconductor substrate outside of the wells, a first impurity layer formed in the vicinity of the depletion region of at least one but not more than two of the first, second, and third regions, and a second impurity layer deeper than the first impurity layer and formed in the region(s) of the substrate in which the first impurity layer is not formed. A method for manufacturing such a CMOS device enables the punch-through voltage characteristics of the first, second, and third transistors to be optimally different, without necessitating any additional, separate mask processing steps.

Abstract: A nonvolatile memory device having a lightly doped source and a method for manufacturing the same are provided. In the nonvolatile memory device, a first insulating layer, a floating gate, a second insulating layer and a control gate are sequentially formed on a semiconductor substrate, and a drain, a lightly doped source and a highly doped source are formed around a surface of the semiconductor substrate. At this time, the highly doped source is shallower than the drain without being overlapped by the floating gate. Thus, the integration of the memory cell can be increased, and the trapping of electrons is reduced in the first insulating layer formed between the floating gate and the lightly doped source, to thereby enhance the characteristics of the memory cell.

Abstract: There is provided a method for manufacturing a nonvolatile memory device using a self-aligned source (SAS) process. The method has the steps of forming a field oxide film on a semiconductor substrate, thus defining an active region on the substrate; sequentially forming a tunnel oxide film, the first conductive layer, an interpoly dielectric layer and the second conductive layer on the substrate; forming a stacked gate of the first and second conductive layers on the active region; forming source/drain regions of first concentration by ion-implanting first impurity on the active region exposed by the stacked gate; removing the exposed field oxide film by using the word line as an etching mask; and exposing the source region of each cell and a portion of the word line and ion-implanting second impurity by using the exposed word line as a mask.

Abstract: A nonvolatile memory device having a predetermined threshold voltage is disclosed. In the nonvolatile memory device comprising a gate electrode including a control gate, a floating gate and a gate insulating layer, a source region and a drain region, a threshold voltage of an initial state applied to a word line such that the floating gate is electrically neutral is set to the mean value between the threshold voltage of a programmed state and the threshold voltage of an erased state. Thus, the amount of negative charges passing through a tunnel oxide layer during a program operation is the same as the amount of positive charges passing through the tunnel oxide layer during an erase operation, and an electric field formed on the tunnel oxide layer is minimized. Thus, the generation of electron traps in the tunnel oxide layer is reduced even though the program or erase operations are repeated, to thereby suppress the loss of the charges stored in the floating gate.

Abstract: A method for fabricating a flash memory device and a flash memory device fabricated by this method are provided. A device isolation film for defining an active region is formed over a predetermined region of a semiconductor substrate and a tunnel insulating film is formed over the surface of the active region. A plurality of floating gate patterns crossing the device isolation film and the active region are formed in parallel. Each of the plurality of floating gate patterns comprises a conductive layer pattern and a capping layer pattern, which are sequentially stacked. An impurity region of a different conductivity type from that of the semiconductor substrate is formed over the active region between the plurality of floating gate patterns. An insulating film pattern filling up a region between the plurality of floating gate patterns is formed.

Abstract: A nonvolatile memory device having a lightly doped source and a method for manufacturing the same are provided. In the nonvolatile memory device, a first insulating layer, a floating gate, a second insulating layer and a control gate are sequentially formed on a semiconductor substrate, and a drain, a lightly doped source and a highly doped source are formed around a surface of the semiconductor substrate. At this time, the highly doped source is shallower than the drain without being overlapped by the floating gate. Thus, the integration of the memory cell can be increased, and the trapping of electrons is reduced in the first insulating layer formed between the floating gate and the lightly doped source, to thereby enhance the characteristics of the memory cell.

Abstract: A nonvolatile semiconductor memory cell array is shown which is composed of a plurality of unit cell-arrays arranged in a repeating pattern. Each of the unit cell-arrays includes a first plurality of cell transistors having control gates coupled in common to a first word line and a second plurality of cell transistors having control gates coupled in common to a second word line. The two word lines are arranged in parallel to one another and perpendicular to a bit line. The bit line is connected in common with drains of both the first and second plurality of cell transistors through a bit line contact. A pair of source lines is arranged along each side of the bit line and parallel to the bit line. Each source line is coupled to one transistor from each of the first and second pluralities of cell transistors through a source line contact.

Abstract: A nonvolatile memory device and a manufacturing method therefor are provided. The nonvolatile memory device includes source pad lines connecting source regions of neighboring cells, parallel to word lines. Thus, the number of common source lines necessary for the overall cell array area can be reduced. Also, the distance between a word line and a contact hole is minimized by providing self-aligned bit line contact holes, thereby minimizing the size of a cell array area.

Abstract: A method for manufacturing a nonvolatile memory device is provided. After forming an etching damage prevention layer on the entire surface of a stacked gate structure and on the entire surface of a semiconductor substrate, a self-aligned source etching process is performed. Thus, damage to side walls of the stacked gate structure and an active region can be prevented during the self-aligned source etching process.

Abstract: A nonvolatile semiconductor memory device includes a p-type semiconductor substrate having a surface region, and bit lines formed as n-type first diffusion regions in the surface region, extending in a column direction. The bit lines define between them a plurality of separated, parallel channel regions, extending in a row direction. A plurality of conductive floating gates are formed over first portions of respective channel regions on a first insulating layer, and extend over portions of the first diffusion regions. A plurality of conductive control gates is formed to extend over the floating gates, and over second portions of the channel regions that are not covered by the floating gates. The control gates are separated from the floating gates and from the second portions by additional insulating layers. A common source line is formed by an elongated conductor extending in the column direction, over the control gates and insulated from them.

Abstract: Methods of forming nonvolatile integrated circuit memory devices having high capacitive coupling ratios include the steps of forming a tunneling oxide layer on a face of a semiconductor substrate and then forming a forming a first conductive layer (e.g., doped polysilicon) on the tunneling oxide layer. A floating gate electrode mask is then patterned on the first conductive layer so as to expose a portion the first conductive layer. A second conductive layer is then patterned on the exposed portion of the first conductive layer and on sidewalls of the floating gate electrode mask, to define a concave or U-shaped floating gate electrode having conductive sidewall extensions. The sidewall extensions increase the effective area of the floating gate electrode and increase the capacitance coupling ratio which enables programming and erasing at reduced voltage levels. A first electrically insulating layer is then formed on the U-shaped floating gate electrode, opposite the tunneling oxide layer.