Abstract: A monolithic three dimensional NAND string includes a vertical semiconductor channel and a plurality of control gate electrodes in different device levels. The string also includes a blocking dielectric layer, a charge storage region and a tunnel dielectric. A first control gate electrode is separated from a second control gate electrode by an air gap located between the major surfaces of the first and second control gate electrodes and/or the charge storage region includes silicide nanoparticles embedded in a charge storage dielectric.

Abstract: An erase process for a 3D stacked memory device allows a portion of a block of memory cells to be erased. In one approach, in a U-shaped NAND string configuration, memory cells in the drain- or source-side columns are erased. In another approach, such as in a U-shaped or a straight NAND string configuration, memory cells in a portion of a column of memory cells are erased, and a dummy memory cell is provided between the erased and non-erased memory cells. A dummy memory cell can be on either side (e.g., above and below) of an erase memory cell, or on either side of a non-erased memory cell. A dummy memory cell is ineligible to store user data, but prevents a downshift in the threshold voltage of an erased memory cell from changing the threshold voltage of a non-erased memory cell, due to capacitive coupling.

Abstract: Three-dimensional NAND stacked memory devices are described that include a stack including alternating word line and dielectric layers and a plurality of NAND strings of memory cells formed in memory holes which extend through the layers. Each memory cell includes a control gate formed by one of the word line layers, and multiple selector devices, each selector device coupled to an end of a corresponding NAND string. The NAND strings are disposed above a substrate, and the selector devices are disposed in the substrate.

Abstract: A three-dimensional memory is formed as an array of memory elements that are formed across multiple layers of planes positioned at different distances above a semiconductor substrate. The memory elements reversibly change a level of electrical conductance in response to a voltage difference being applied across them. The three-dimensional array includes a two-dimensional array of pillar lines acting as local vertical bit lines through the multiple layers of planes which together with arrays of word lines on each plane are used to access the memory elements. The three-dimensional memory is formed over a CMOS substrate with an intermediate pillar select layer. The pillar select layer is formed with a plurality of pillar select devices which are switching transistors formed outside the CMOS and serve to switch selected rows of pillar lines to corresponding metal lines on the substrate.

Abstract: An erase operation for a 3D stacked memory device assigns storage elements to groups according to an expected erase speed. The storage elements are then erased according to their group to provide a more uniform erase depth and a tighter erase distribution. In one approach, the control gate voltages are set differently for the different groups to slow down the storage elements which are expected to have a faster programming speed. An erase or inhibit status can be set for all groups together. In another approach, the control gate voltages are common for the different groups but an erase or inhibit status is set for each group separately.

Abstract: A NAND device has at least a 3×3 array of vertical NAND strings in which the control gate electrodes are continuous in the array and do not have an air gap or a dielectric filled trench in the array. The NAND device is formed by first forming a lower select gate level having separated lower select gates, then forming plural memory device levels containing a plurality of NAND string portions, and then forming an upper select gate level over the memory device levels having separated upper select gates.

Abstract: Monolithic, three dimensional NAND strings include a semiconductor channel, at least one end portion of the semiconductor channel extending substantially perpendicular to a major surface of a substrate, a plurality of control gate electrodes having a strip shape extending substantially parallel to the major surface of the substrate, the blocking dielectric comprising a plurality of blocking dielectric segments, a plurality of discrete charge storage segments, and a tunnel dielectric located between each one of the plurality of the discrete charge storage segments and the semiconductor channel.

Abstract: A method of making a vertical NAND device includes forming a lower portion of a memory stack over a substrate, forming a lower portion of memory openings in the lower portion of the memory stack, and at least partially filling the lower portion of the memory openings with a sacrificial material. The method also includes forming an upper portion of the memory stack over the lower portion of the memory stack and over the sacrificial material, forming an upper portion of the memory openings in the upper portion of the memory stack to expose the sacrificial material in the lower portion of the memory openings, removing the sacrificial material to connect the lower portion of the memory openings with a respective upper portion of the memory openings to form continuous memory openings, and forming a semiconductor channel in each continuous memory opening.

Abstract: A monolithic three dimensional NAND string includes a vertical semiconductor channel and a plurality of control gate electrodes in different device levels. The string also includes a blocking dielectric layer, a charge storage region and a tunnel dielectric. A first control gate electrode is separated from a second control gate electrode by an air gap located between the major surfaces of the first and second control gate electrodes and/or the charge storage region includes silicide nanoparticles embedded in a charge storage dielectric.

Abstract: A method of making a semiconductor device including forming a sacrificial feature over a substrate, forming a plurality of etch through regions having an etch through material and an etch stop region having an etch stop material over the sacrificial feature, forming a stack of alternating layers of a first material and a second material over the plurality of the etch through regions and the plurality of the etch stop regions, etching the stack to form a plurality of openings through the stack and through the etch through regions to expose the sacrificial feature, such that the etch through material is etched preferentially compared to the first and the second materials of the stack, removing the sacrificial feature through the plurality of openings and etching the stack to form a slit trench up to or only partially through the etch stop region, such that the first and the second materials of the stack are etched preferentially compared to the etch stop material.

Abstract: A monolithic three dimensional NAND string includes a semiconductor channel located over a substrate, a plurality of control gates extending substantially parallel to the major surface of the substrate including a first control gate located in a first device level and a second control gate located in a second device level located over the substrate and below the first device level, a charge storage material including a silicide layer located in the first device level and in the second device level, a blocking dielectric located between the charge storage material and the plurality of control gates, and a tunnel dielectric located between the charge storage material and the semiconductor channel. The tunnel dielectric has a straight sidewall, portions of the blocking dielectric have a clam shape, and each of the plurality of control gates is located at least partially in an opening in the clam-shaped portion of the blocking dielectric.

Abstract: A stack can be patterned by a first etch process to form an opening defining sidewall surfaces of a patterned material stack. A masking layer can be non-conformally deposited on sidewalls of an upper portion of the patterned material stack, while not being deposited on sidewalls of a lower portion of the patterned material stack. The sidewalls of a lower portion of the opening can be laterally recessed employing a second etch process, which can include an isotropic etch component. The sidewalls of the upper portion of the opening can protrude inward toward the opening to form an overhang over the sidewalls of the lower portion of the opening. The overhang can be employed to form useful structures such as an negative offset profile in a floating gate device or vertically aligned control gate electrodes for vertical memory devices.

Abstract: A three dimensional memory device including a substrate and a semiconductor channel. At least one end portion of the semiconductor channel extends substantially perpendicular to a major surface of the substrate. The device also includes at least one charge storage region located adjacent to semiconductor channel and a plurality of control gate electrodes having a strip shape extending substantially parallel to the major surface of the substrate. The plurality of control gate electrodes include at least a first control gate electrode located in a first device level and a second control gate electrode located in a second device level located over the major surface of the substrate and below the first device level. Each of the plurality of control gate electrodes includes a first edge surface which is substantially free of silicide, the first edge surface facing the semiconductor channel and the at least one charge storage region and a silicide located on remaining surfaces of the control gate electrode.

Abstract: A method of making a monolithic three dimensional NAND string including providing a stack of alternating first material layers and second material layers over a substrate. The first material layers comprise an insulating material and the second material layers comprise sacrificial layers. The method also includes forming a back side opening in the stack, selectively removing the second material layers through the back side opening to form back side recesses between adjacent first material layers and forming a blocking dielectric inside the back side recesses and the back side opening. The blocking dielectric has a clam shaped regions inside the back side recesses. The method also includes forming a plurality of copper control gate electrodes in the respective clam shell shaped regions of the blocking dielectric in the back side recesses.

Abstract: An erase process for a 3D stacked memory device allows a portion of a block of memory cells to be erased. In one approach, in a U-shaped NAND string configuration, memory cells in the drain- or source-side columns are erased. In another approach, such as in a U-shaped or a straight NAND string configuration, memory cells in a portion of a column of memory cells are erased, and a dummy memory cell is provided between the erased and non-erased memory cells. A dummy memory cell can be on either side (e.g., above and below) of an erase memory cell, or on either side of a non-erased memory cell. A dummy memory cell is ineligible to store user data, but prevents a downshift in the threshold voltage of an erased memory cell from changing the threshold voltage of a non-erased memory cell, due to capacitive coupling.

Abstract: A three-dimensional memory is formed as an array of memory elements that are formed across multiple layers of planes positioned at different distances above a semiconductor substrate. The memory elements reversibly change a level of electrical conductance in response to a voltage difference being applied across them. The three-dimensional array includes a two-dimensional array of pillar lines acting as local vertical bit lines through the multiple layers of planes which together with arrays of word lines on each plane are used to access the memory elements. The three-dimensional memory is formed over a CMOS substrate with an intermediate pillar select layer. The pillar select layer is formed with a plurality of pillar select devices which are switching transistors formed outside the CMOS and serve to switch selected rows of pillar lines to corresponding metal lines on the substrate.

Abstract: A vertical NAND string device includes a semiconductor channel, where at least one end portion of the semiconductor channel extends substantially perpendicular to a major surface of a substrate, at least one semiconductor or electrically conductive landing pad embedded in the semiconductor channel, a tunnel dielectric located adjacent to the semiconductor channel, a charge storage region located adjacent to the tunnel dielectric, a blocking dielectric located adjacent to the charge storage region and a plurality of control gate electrodes extending substantially parallel to the major surface of the substrate.

Abstract: A NAND device has at least a 3×3 array of vertical NAND strings in which the control gate electrodes are continuous in the array and do not have an air gap or a dielectric filled trench in the array. The NAND device is formed by first forming a lower select gate level having separated lower select gates, then forming plural memory device levels containing a plurality of NAND string portions, and then forming an upper select gate level over the memory device levels having separated upper select gates.

Abstract: A method of making a semiconductor device includes forming a stack of alternating layers of a first material and a second material over a substrate, etching the stack to form at least one opening extending partially through the stack and forming a masking layer on a sidewall and bottom surface of the at least one opening. The method also includes removing the masking layer from the bottom surface of the at least one opening while leaving the masking layer on the sidewall of the at least one opening, and further etching the at least one opening to extend the at least one opening further through the stack while the masking layer remains on the sidewall of the at least one opening.

Abstract: A three dimensional memory device including a substrate and a semiconductor channel. At least one end portion of the semiconductor channel extends substantially perpendicular to a major surface of the substrate. The device also includes at least one charge storage region located adjacent to semiconductor channel and a plurality of control gate electrodes having a strip shape extending substantially parallel to the major surface of the substrate. The plurality of control gate electrodes include at least a first control gate electrode located in a first device level and a second control gate electrode located in a second device level. Each of the plurality of control gate electrodes includes a first edge surface which is substantially free of silicide, the first edge surface facing the semiconductor channel and the at least one charge storage region and a silicide located on remaining surfaces of the control gate electrode.