Abstract: A nonvolatile memory cell includes a steering element located in series with a storage element, where the storage element comprises a carbon material. A method of programming the cell includes applying a reset pulse to change a resistivity state of the carbon material from a first state to a second state which is higher than the first state, and applying a set pulse to change a resistivity state of the carbon material from the second state to a third state which is lower than the second state. A fall time of the reset pulse is shorter than a fall time of the set pulse.
Abstract: Methods of forming planar carbon nanotube (“CNT”) resistivity-switching materials for use in memory cells are provided, that include depositing first dielectric material, patterning the first dielectric material, etching the first dielectric material to form a feature within the first dielectric material, depositing CNT resistivity-switching material over the first dielectric material to fill the feature at least partially with the CNT resistivity-switching material, depositing second dielectric material over the CNT resistivity-switching material, and planarizing the second dielectric material and the CNT resistivity-switching material so as to expose at least a portion of the CNT resistivity-switching material within the feature. Other aspects are also provided.
Abstract: A non-volatile storage system includes a substrate, control circuitry on the substrate, a three dimensional memory array (above the substrate) that includes a plurality of memory cells with reversible resistance-switching elements, and circuits to SET and RESET the resistance-switching elements. The circuits that RESET the resistance-switching elements provide a pulse to the memory cells that is large enough in magnitude to SET and RESET the memory cells, and long enough to potentially RESET the memory cell but not long enough to SET the memory cells.
Abstract: A very high density field programmable memory is disclosed. An array is formed vertically above a substrate using several layers, each layer of which includes vertically fabricated memory cells. The cell in an N level array may be formed with N+1 masking steps plus masking steps needed for contacts. Maximum use of self alignment techniques minimizes photolithographic limitations. In one embodiment the peripheral circuits are formed in a silicon substrate and an N level array is fabricated above the substrate.
Type:
Grant
Filed:
March 16, 2010
Date of Patent:
July 12, 2011
Assignee:
SanDisk 3D LLC
Inventors:
Mark G. Johnson, Thomas H. Lee, James M. Cleeves
Abstract: A non-volatile storage apparatus includes Y lines, a common X line, multiple storage elements, a dummy element and control circuitry in communication with the common X line and the Y lines. Each element is connected to the common X line and the dummy element is also connected to a particular Y line. The control circuitry provides control signals to the common X line and the Y lines to change a first storage element from a first to a second state by passing a current into the first storage element from the particular Y line through the dummy element. The control circuitry controls the common X line and Y lines to sequentially change additional storage elements from the first to the second state by passing currents into the additional storage elements previously changed to the second state and their associated different Y lines.
Abstract: There is provided a monolithic three dimensional array of charge storage devices which includes a plurality of device levels, wherein at least one surface between two successive device levels is planarized by chemical mechanical polishing.
Type:
Application
Filed:
February 14, 2011
Publication date:
June 30, 2011
Applicant:
SanDisk 3D LLC
Inventors:
Thomas H. Lee, Vivek Subramanian, James M. Cleeves, Andrew J. Walker, Christopher J. Petti, Igor G. Kouznetzov, Mark G. Johnson, Paul Michael Farmwald, Brad Herner
Abstract: A metal-insulator diode is disclosed. In one aspect, the metal-insulator diode comprises first and second electrode and first and second insulators arraigned as follows. An insulating region has a trench formed therein. The trench has a bottom and side walls. The first electrode, which comprises a first metal, is on the side walls and over the bottom of the trench. A first insulator has a first interface with the first electrode. At least a portion of the first insulator is within the trench. A second insulator has a second interface with the first insulator. At least a portion of the second insulator is within the trench. The second electrode, which comprises a second metal, is in contact with the second insulator. The second electrode at least partially fills the trench.
Type:
Grant
Filed:
September 29, 2008
Date of Patent:
June 28, 2011
Assignee:
SanDisk 3D LLC
Inventors:
Deepak C. Sekar, Tanmay Kumar, Peter Rabkin, Er-Xuan Ping, Xiying Chen
Abstract: A photolithographic method uses different exposure patterns. In one aspect, a photo-sensitive layer on a substrate is subject to a first exposure using optics having a first exposure pattern, such as an x-dipole pattern, followed by exposure using optics having a second exposure pattern, such as a y-dipole pattern, via the same mask, and with the photo-sensitive layer fixed relative to the mask. A 2-D post pattern with a pitch of approximately 70-150 nm may be formed in a layer beneath the photo-sensitive layer using 157-193 nm UV light, and hyper-numerical aperture optics, in one approach. In another aspect, hard baking is performed after both of the first and second exposures to erase a memory effect of photoresist after the first exposure. In another aspect, etching of a hard mask beneath the photo-sensitive layer is performed after both of the first and second exposures.
Type:
Grant
Filed:
June 8, 2010
Date of Patent:
June 28, 2011
Assignee:
SanDisk 3D LLC
Inventors:
Yung-Tin Chen, Steven J. Radigan, Paul Poon, Michael Konevecki
Abstract: Column redundancy data is selectively retrieved in a memory device according to a set of storage elements which is currently being accessed, such as in a read or write operation. The memory device is organized into sets of storage elements such as logical blocks, where column redundancy data is loaded from a non-volatile storage location to a volatile storage location for one or more particular blocks which are being accessed. The volatile storage location need only be large enough to store the current data entries. The size of the set of storage elements for which column redundancy data is concurrently loaded can be configured based on an expected maximum number of defects and a desired repair probability. During a manufacturing lifecycle, the size of the set can be increased as the number of defects is reduced due to improvements in manufacturing processes and materials.
Abstract: A very dense cross-point memory array of multi-level read/write two-terminal memory cells, and methods for its programming, are described. Multiple states are achieved using two or more films that each have bi-stable resistivity states, rather than “tuning” the resistance of a single resistive element. An exemplary memory cell includes a vertical pillar diode in series with two different bi-stable resistance films. Each bi-stable resistance film has both a high resistance and low resistance state that can be switched with appropriate application of a suitable bias voltage and current. Such a cross-point array is adaptable for two-dimensional rewritable memory arrays, and also particularly well-suited for three-dimensional rewritable (3D R/W) memory arrays.
Abstract: A method of forming a reversible resistance-switching metal-insulator-metal structure is provided, the method including forming a first non-metallic conducting layer, forming a non-conducting layer above the first non-metallic conducting layer, forming a second non-metallic conducting layer above the non-conducting layer, etching the first non-metallic conducting layer, non-conducting layer and second non-metallic conducting layer to form a pillar, and disposing a carbon material layer about a sidewall of the pillar. Other aspects are also provided.
Abstract: A method of making a semiconductor device includes providing an insulating layer containing a plurality of openings, forming a first semiconductor layer in the plurality of openings in the insulating layer and over the insulating layer, and removing a first portion of the first semiconductor layer, such that first conductivity type second portions of the first semiconductor layer remain in lower portions of the plurality of openings in the insulating layer, and upper portions of the plurality of openings in the insulating layer remain unfilled. The method also includes forming a second semiconductor layer in the upper portions of the plurality of openings in the insulating layer and over the insulating layer, and removing a first portion of the second semiconductor layer located over the insulating layer.
Type:
Application
Filed:
February 14, 2011
Publication date:
June 9, 2011
Applicant:
SanDisk 3D LLC
Inventors:
Vance DUNTON, S. Brad Herner, Paul Wai Kie Poon, Chuanbin Pan, Michael Chan, Michael Konevecki, Usha Raghuram
Abstract: A non-volatile memory device includes a plurality of pillars, where each of the plurality of pillars contains a non-volatile memory cell containing a steering element and a storage element and at least one of a top corner or a bottom corner of each of the plurality of pillars is rounded. A method of making non-volatile memory device includes forming a stack of device layers, and patterning the stack to form a plurality of pillars, where each of the plurality of pillars contains a non-volatile memory cell that contains a steering element and a storage element, and where at least one of top corner or bottom corner of each of the plurality of pillars is rounded.
Abstract: A method of plasma etching transition metal oxide thin films using carbon monoxide as the primary source gas. This permits carbonyl chemistries to be used at ambient temperature, without heating.
Abstract: A structure and a method of manufacturing a three dimensional memory using a number of bit line masks that is less than the number of device layers. A first bit line mask is used to form a first bit line layer in a first device level. The first bit line layer comprises first bit lines. The first bit line mask is also used to form a second bit line layer in a second device level. The second bit line layer comprises second bit lines. The first bit lines and the second bit lines have different electrical connections to a bit line connection level despite employing the same mask pattern.
Abstract: A method of programming a memory cell comprises applying a reverse bias to the memory cell using a temporary resistor in series with the memory cell. The memory cell comprises a diode and a resistivity switching material element in series. The state of the resistivity switching material element changes from a first initial state to a second state different from the first state.
Type:
Grant
Filed:
December 19, 2008
Date of Patent:
May 17, 2011
Assignee:
SanDisk 3D LLC
Inventors:
Yibo Nian, Tanmay Kumar, Roy E. Scheuerlein
Abstract: A method of biasing a nonvolatile memory array. The nonvolatile memory array includes a first and second plurality of Y lines, a plurality of X lines, a first and second plurality of two terminal memory cells. Each first and second memory cell is coupled to one of the first or second plurality of Y lines and one of the plurality of X lines, respectively. Substantially all of the first plurality and second plurality of Y lines are driven to a Y line unselect voltage. At least one selected Y line of the first plurality of Y lines is driven to a Y line select voltage while floating remaining Y lines of the first plurality of Y lines and while driving substantially all of the second plurality of Y lines to the Y line unselect voltage.
Abstract: Forming a metal-insulator diode and carbon memory element in a single damascene process is disclosed. A trench having a bottom and a sidewall is formed in an insulator. A first diode electrode is formed in the trench during a single damascene process. A first insulating region comprising a first insulating material is formed in the trench during the single damascene process. A second insulating region comprising a second insulating material is formed in the trench during the single damascene process. A second diode electrode is formed in the trench during the single damascene process. The first insulating region and the second insulating region reside between the first diode electrode and the second diode electrode to form a metal-insulator-insulator-metal (MIIM) diode. A region of carbon is formed in the trench during the single damascene process. At least a portion of the carbon is electrically in series with the MIIM diode.
Type:
Grant
Filed:
September 24, 2009
Date of Patent:
May 3, 2011
Assignee:
SanDisk 3D LLC
Inventors:
April Dawn Schricker, Deepak C. Sekar, Andy Fu, Mark Clark
Abstract: A method of making a semiconductor device includes forming a first photoresist layer over an underlying layer, patterning the first photoresist layer into a first photoresist pattern, wherein the first photoresist pattern comprises a plurality of spaced apart first photoresist features located over the underlying layer, and etching the underlying layer using the first photoresist pattern as a mask to form a plurality of first spaced apart features. The method further includes removing the first photoresist pattern, forming a second photoresist layer over the plurality of first spaced apart features, and patterning the second photoresist layer into a second photoresist pattern, wherein the second photoresist pattern comprises a plurality of second photoresist features covering edge portions of the plurality of first spaced apart features.
Abstract: The present invention provides apparatus, methods, and systems for a memory layer layout for a three-dimensional memory. The memory layer includes a plurality of memory array blocks; a plurality of memory lines coupled to the memory array blocks; and a plurality of zia contact areas for coupling the memory layer to other memory layers in a three-dimensional memory. The memory lines extend from the memory array blocks and are formed using a sidewall defined process. The memory lines have a half pitch dimension smaller than the nominal minimum feature size capability of a lithography tool used in forming the memory lines. The zia contact areas have a dimension that is approximately four times the half pitch dimension of the memory lines. The memory lines are arranged in a pattern adapted to allow a single memory line to intersect a single zia contact area and to provide area between other memory lines for other zia contact areas. Numerous additional aspects are disclosed.
Type:
Application
Filed:
October 26, 2010
Publication date:
April 28, 2011
Applicant:
SANDISK 3D LLC
Inventors:
Roy E. Scheuerlein, Christopher J. Petti, Yoichiro Tanaka