Abstract: The present invention provides apparatus, methods, and systems for fabricating memory lines and structures using double sidewall patterning for four times half pitch relief patterning. The invention includes forming features from a first template layer disposed above a substrate, forming half-pitch sidewall spacers adjacent the features, forming smaller features in a second template layer by using the half-pitch sidewall spacers as a hardmask, forming quarter-pitch sidewall spacers adjacent the smaller features, and forming conductor features from a conductor layer by using the quarter-pitch sidewall spacers as a hardmask. Numerous additional aspects are disclosed.
Abstract: The present invention provides apparatus, methods, and systems for fabricating memory structures methods of forming pillars for memory cells using sequential sidewall patterning. The invention includes forming first features from a first template layer disposed above a memory layer stack; forming first sidewall spacers adjacent the first features; forming second features that extend in a first direction in a mask layer by using the first sidewall spacers as a hardmask; depositing a second template layer on the mask layer; forming third features from the second template layer; forming second sidewall spacers adjacent the third features; and forming fourth features that extend in a second direction in the mask layer by using the second sidewall spacers as a hardmask. 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
Abstract: A method of making a semiconductor device includes forming a first layer comprising a seed material over an underlying layer, forming a second layer comprising a sacrificial material over the first layer, the sacrificial material being different from the seed material, patterning the first layer and the second layer into a plurality of separate features, forming an insulating filling material between the plurality of the separate features, removing the sacrificial material from the separate features to form a plurality of openings in the insulating filling material such that the seed material is exposed in the plurality of openings, and growing a semiconductor material on the exposed seed material in the plurality of openings.
Type:
Grant
Filed:
July 15, 2009
Date of Patent:
April 19, 2011
Assignee:
SanDisk 3D LLC
Inventors:
Raghuveer S. Makala, Vance Dunton, Yoichiro Tanaka, Steven Maxwell, Tong Zhang, Steven J. Radigan
Abstract: In a first preferred embodiment of the present invention, conductive features are formed on a first dielectric etch stop layer, and a second dielectric material is deposited over and between the conductive features. A via etch to the conductive features which is selective between the first and second dielectrics will stop on the dielectric etch stop layer, limiting overetch. In a second embodiment, a plurality of conductive features is formed in a subtractive pattern and etch process, filled with a dielectric fill, and then a surface formed coexposing the conductive features and dielectric fill. A dielectric etch stop layer is deposited on the surface, then a third dielectric covers the dielectric etch stop layer. When a contact is etched through the third dielectric, this selective etch stops on the dielectric etch stop layer. A second etch makes contact to the conductive features.
Abstract: A method of making a device includes forming a first sacrificial layer over an underlying layer, forming a first photoresist layer over the first sacrificial layer, patterning the first photoresist layer to form first photoresist features, rendering the first photoresist features insoluble to a solvent, forming a second photoresist layer over the first photoresist features, patterning the second photoresist layer to form second photoresist features, etching the first sacrificial layer using both the first and the second photoresist features as a mask to form first sacrificial features, forming a spacer layer over the first sacrificial features, etching the spacer layer to form spacer features and to expose the sacrificial features, removing the first sacrificial features, and etching at least part of the underlying layer using the spacer features as a mask.
Type:
Grant
Filed:
January 12, 2010
Date of Patent:
April 12, 2011
Assignee:
SanDisk 3D LLC
Inventors:
Natalie Nguyen, Paul Wai Kie Poon, Steven J. Radigan, Michael Konevecki, Yung-Tin Chen
Abstract: A method of programming a carbon nanotube memory cell is provided, wherein the memory cell comprises a first conductor, a steering element, a carbon nanotube fabric, and a second conductor, wherein the steering element and the carbon nanotube fabric are arranged electrically in series between the first conductor and the second conductor, and wherein the entire carbon nanotube memory cell is formed above a substrate, the carbon nanotube fabric having a first resistivity, the method including applying a first electrical set pulse between the first conductor and the second conductor, wherein, after application of the first electrical set pulse, the carbon nanotube fabric has a second resistivity, the second resistivity less than the first resistivity. Other aspects are also provided.
Abstract: A non-volatile memory device includes a first electrode, a diode steering element, at least three resistivity switching storage elements, and a second electrode. The diode steering element electrically contacts the first electrode and the at least three resistivity switching storage elements. The second electrode electrically contacts only one of the at least three resistivity switching storage elements.
Abstract: Circuitry for performing a set or reset process for a reversible resistance-switching memory element in a memory device. A ramped voltage is applied to the memory cell and its state is constantly monitored so that the voltage can be discharged as soon as the set or reset process is completed, avoiding possible disturbs to the memory cell. One set circuit ramps the voltage using a current source, while detecting a current peak using an op-amp loop. One reset circuit ramps the voltage using an op-amp loop, while detecting a current peak by continuing to draw current at the peak current to maintain the output signal stable. Another set circuit ramps the voltage using an op-amp loop and a source-follower configuration. Another reset circuit ramps the voltage using an op-amp loop and a source-follower configuration with level shifting to reduce power consumption. Faster detection and shutoff, and stable operation, are achieved.
Abstract: A method of making a nonvolatile memory device includes fabricating a diode in a low resistivity, programmed state without an electrical programming step. The memory device includes at least one memory cell. The memory cell is constituted by the diode and electrically conductive electrodes contacting the diode.
Abstract: The invention provides for polysilicon vias connecting conductive polysilicon layers formed at different heights. Polysilicon vias are advantageously used in a monolithic three dimensional memory array of charge storage transistors. Polysilicon vias according to the present invention can be used, for example, to connect the channel layer of a first device level of charge storage transistor memory cells to the channel layer of a second device layer of such cells formed above the first device level. Similarly, vias according to the present invention can be used to connect the wordline of a first device level of charge storage transistor memory cells to the channel layer of a second device layer of such cells.
Type:
Grant
Filed:
October 4, 2010
Date of Patent:
March 29, 2011
Assignee:
SanDisk 3D LLC
Inventors:
Michael W. Konevecki, Usha Raghuram, Maitreyee Mahajani, Sucheta Nallamothu, Andrew J. Walker, Tanmay Kumar
Abstract: An antifuse contains a first silicide layer, a grown silicon oxide antifuse layer on a first surface of the first silicide layer, and a first semiconductor layer having a first surface in contact with the antifuse layer.
Abstract: The invention provides for polysilicon vias connecting conductive polysilicon layers formed at different heights. Polysilicon vias are advantageously used in a monolithic three dimensional memory array of charge storage transistors. Polysilicon vias according to the present invention can be used, for example, to connect the channel layer of a first device level of charge storage transistor memory cells to the channel layer of a second device layer of such cells formed above the first device level. Similarly, vias according to the present invention can be used to connect the wordline of a first device level of charge storage transistor memory cells to the channel layer of a second device layer of such cells.
Type:
Grant
Filed:
June 22, 2009
Date of Patent:
March 29, 2011
Assignee:
SanDisk 3D LLC
Inventors:
Michael W. Konevecki, Usha Raghuram, Maitreyee Mahajani, Sucheta Nallamothu, Andrew J. Walker, Tanmay Kumar
Abstract: A non-volatile memory device includes a first electrode, a diode steering element, at least three resistivity switching storage elements, and a second electrode. The diode steering element electrically contacts the first electrode and the at least three resistivity switching storage elements. The second electrode electrically contacts only one of the at least three resistivity switching storage elements.
Abstract: A method of making a non-volatile memory device includes providing a substrate having a substrate surface, and forming a non-volatile memory array over the substrate surface. The non-volatile memory array includes an array of semiconductor diodes, and each semiconductor diode of the array of semiconductor diodes is disposed substantially parallel to the substrate surface.
Type:
Application
Filed:
November 18, 2010
Publication date:
March 17, 2011
Applicant:
SanDisk 3D LLC
Inventors:
Steven Maxwell, Michael Konevecki, Mark H. Clark, Usha Raghuram
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:
Grant
Filed:
January 15, 2008
Date of Patent:
March 15, 2011
Assignee:
SanDisk 3D LLC
Inventors:
Vance Dunton, S. Brad Herner, Paul Wai Kie Poon, Chuanbin Pan, Michael Chan, Michael Konevecki, Usha Raghuram
Abstract: In some aspects, a method of forming a memory cell is provided that includes (1) forming a first conductor above a substrate; (2) forming a reversible resistance-switching element above the first conductor using a selective growth process; (3) forming a diode above the first conductor; and (4) forming a second conductor above the diode and the reversible resistance-switching element. Numerous other aspects are provided.
Type:
Grant
Filed:
June 29, 2007
Date of Patent:
March 8, 2011
Assignee:
Sandisk 3D LLC
Inventors:
April Schricker, Brad Herner, Mark Clark
Abstract: The present invention provides methods and apparatus for adjusting voltages of bit and word lines to create short programming pulses to program a memory cell. The invention may include setting a first line connected to a memory cell to a first voltage from a first line standby voltage, charging a second line connected to the memory cell to a predetermined voltage from a second line standby voltage, switching the first line from the first voltage to a second voltage, and switching the first line from the second voltage to the first voltage. The voltage difference between the first voltage and the predetermined voltage is such that a safe voltage results that does not program the memory cell. A voltage difference between the second voltage and the predetermined voltage is such that a programming voltage operative to program the memory cell results. The switching operations together may create a first pulse.
Abstract: The present invention provides methods and apparatus for adjusting voltages of bit and word lines to program a two terminal memory cell. The invention may include setting a first line connected to a memory cell to a first voltage from a first line standby voltage, charging a second line connected to the memory cell to a predetermined voltage from a second line standby voltage, and switching the first line from the first voltage to a second voltage. The voltage difference between the first voltage and the predetermined voltage is such that a safe voltage results that does not program the memory cell. A voltage difference between the second voltage and the predetermined voltage is such that a programming voltage operative to program the memory cell results.
Abstract: Methods and apparatus are provided that include reading a plurality of sets of program pulse tuning instructions from a memory page, the memory page including a plurality of memory cells; and creating a plurality of program pulses in accordance with the plurality of sets of program pulses to program the plurality of memory cells. The plurality of sets of program pulse tuning instructions may be different from one another in at least one respect.
Abstract: An integrated circuit including vertically oriented diode structures between conductors and methods of fabricating the same are provided. The diode is a metal-insulator diode having a first metal layer, a first insulating layer, a second insulating layer and a second metal layer. At least one asymmetric interface state is provided at the intersection of at least two of the layers to increase the ratio of the diode's on-current to its reverse bias leakage current. In various examples, the asymmetric interface state is formed by a positive or negative sheet charge that alters the barrier height and/or electric field at one or more portions of the diode. Two-terminal devices such as passive element memory cells can utilize the diode as a steering element in series with a state change element. The devices can be formed using pillar structures at the intersections of upper and lower conductors.
Type:
Grant
Filed:
December 16, 2008
Date of Patent:
March 1, 2011
Assignee:
SanDisk 3D LLC
Inventors:
Xiying Chen, Deepak Chandra Sekar, Mark Clark, Dat Nguyen, Tanmay Kumar