Abstract: In a first aspect, a method of forming a memory cell is provided that includes (1) forming a metal-insulator-metal (MIM) stack, the MIM stack including (a) a first conductive carbon layer; (b) a low-hydrogen, silicon-containing carbon layer above the first conductive carbon layer; and (c) a second conductive carbon layer above the low-hydrogen, silicon-containing carbon layer; and (2) forming a steering element coupled to the MIM stack. Numerous other aspects are provided.
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 diode above the first conductor; (3) forming a reversible resistance-switching element above the first conductor using a selective deposition process; 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:
July 31, 2012
Assignee:
SanDisk 3D LLC
Inventors:
April Schricker, Brad Herner, Michael W. Konevecki
Abstract: A nonvolatile memory array architecture includes a resistive element between each common source/drain (intermediate) node and data line (or bit line), in an otherwise virtual ground-like memory array having serially-connected transistors coupled to the same word line. However, every N+1 transistors the corresponding resistive element is omitted (or generally kept in a low resistance state) to form transistor strings. This achieves an array density of 4F2*(N+1)/N, which approaches 4F2 array density for reasonable values of N. Such memory arrays are well suited for use in a three-dimensional memory array having distinct memory planes stacked above each other on multiple levels above a substrate.
Abstract: In the present invention, a metal oxide or nitride compound which is a wide-band-gap semiconductor abuts a silicon, germanium, or alloy of silicon and/or germanium of the opposite conductivity type to form a p-n heterojunction. This p-n heterojunction can be used to advantage in various devices. In preferred embodiments, one terminal of a vertically oriented p-i-n heterojunction diode is a metal oxide or nitride layer, while the rest of the diode is formed of a silicon or silicon-germanium resistor. For example, a diode may include a heavily doped n-type silicon region, an intrinsic silicon region, and a nickel oxide layer serving as the p-type terminal. Many of these metal oxides and nitrides exhibit resistivity-switching behavior, and such a heterojunction diode can be used in a nonvolatile memory cell, for example in a monolithic three dimensional memory array.
Abstract: A method of making a device includes providing a first device level containing first semiconductor rails separated by first insulating features, forming a sacrificial layer over the first device level, patterning the sacrificial layer and the first semiconductor rails in the first device level to form a plurality of second rails extending in a second direction, wherein the plurality of second rails extend at least partially into the first device level and are separated from each other by rail shaped openings which extend at least partially into the first device level, forming second insulating features between the plurality of second rails, removing the sacrificial layer, and forming second semiconductor rails between the second insulating features in a second device level over the first device level. The first semiconductor rails extend in a first direction. The second semiconductor rails extend in the second direction different from the first direction.
Type:
Grant
Filed:
December 2, 2011
Date of Patent:
July 17, 2012
Assignee:
SanDisk 3D LLC
Inventors:
Vinod Robert Purayath, George Matamis, James Kai, Takashi Orimoto
Abstract: A non-volatile storage device includes a substrate, a monolithic three-dimensional memory array of non-volatile storage elements arranged above a portion of the substrate, a plurality of sense amplifiers in communication with the non-volatile storage elements, a plurality of temporary storage devices in communication with the sense amplifiers, a page register in communication with the temporary storage devices, and one or more control circuits. The one or more control circuits are in communication with the page register, the temporary storage devices and the sense amplifiers. The sense amplifiers are arranged on the substrate underneath the monolithic three-dimensional memory array. The temporary storage devices are arranged on the substrate underneath the monolithic three-dimensional memory array. The page register is arranged on the substrate in an area that is not underneath the monolithic three-dimensional memory array.
Abstract: During the manufacture of a set of non-volatile resistance-switching memory elements, a forming process is performed in which a voltage is applied over forming period until a conductive filament is formed in a resistance-switching layer. A heat source at a temperature of 50° C. to 150° C. is applied to expedite the forming process while reducing the required magnitude of the applied voltage. Manufacturing time and reliability are improved. After the forming process, an expedited training process can be performed in which a fixed number of cycles of voltage pulses are applied without verifying the memory elements. Subsequently, the memory elements are verified by determining their read current in an evaluation. Another fixed number of cycles of voltage pulses is applied without verifying the memory elements, if the memory elements do not pass the evaluation.
Abstract: A non-volatile storage system includes technology for skipping programming cycles while programming a page (or other unit) of data. While programming a current subset of the page (or other unit) of data, the system will evaluate whether the next subsets of the page (or other unit) of data should be programmed into non-volatile storage elements or skipped. Subsets of the page (or other unit) of data that should not be skipped are programmed into non-volatile storage elements. Some embodiments include transferring the appropriate data to temporary latches/registers, in preparation for programming, concurrently with the evaluation of whether to program or skip the programming.
Type:
Grant
Filed:
December 15, 2009
Date of Patent:
July 3, 2012
Assignee:
SanDisk 3D LLC
Inventors:
Gopinath Balakrishnan, Luca Fasoli, Tz-Yi Liu, Yuheng Zhang, Yan Li
Abstract: The embodiments described herein can be used to enable one-time or few-time programmable memories to work with existing consumer electronic devices (such as those that work with flash—an erasable, non-volatile memory) without requiring a firmware upgrade, thereby providing backwards compatibility while minimizing user impact. As such, these embodiments are a viable way to bridge one-time or few-time programmable memories with existing consumer electronic devices that have flash card slots. These embodiments also allow future consumer electronic devices to be designed without updating firmware to include a file system customized for a one-time or few-time programmable memory.
Type:
Grant
Filed:
November 1, 2010
Date of Patent:
June 26, 2012
Assignee:
SanDisk 3D LLC
Inventors:
Christopher S. Moore, Adrian Jeday, Matt Fruin, Chia Yang, Derek Bosch
Abstract: A memory cell is provided that includes a first conductor, a second conductor, a steering element that is capable of providing substantially unidirectional current flow, and a state change element coupled in series with the steering element. The state change element is capable of retaining a programmed state, and the steering element and state change element are vertically aligned with one another. Other aspects are also provided.
Type:
Grant
Filed:
October 7, 2010
Date of Patent:
June 26, 2012
Assignee:
SanDisk 3D LLC
Inventors:
Mark G. Johnson, Thomas H. Lee, Vivek Subramanian, Paul Michael Farmwald, James M. Cleeves
Abstract: A semiconductor p-i-n diode and method for forming the same are described herein. In one aspect, a SiGe region is formed between a region doped to have one conductivity (either p+ or n+) and an electrical contact to the p-i-n diode. The SiGe region may serve to lower the contact resistance, which may increase the forward bias current. The doped region extends below the SiGe region such that it is between the SiGe region and an intrinsic region of the diode. The p-i-n diode may be formed from silicon. The doped region below the SiGe region may serve to keep the reverse bias current from increasing as result of the added SiGe region. In one embodiment, the SiGe is formed such that the forward bias current of an up-pointing p-i-n diode in a memory array substantially matches the forward bias current of a down-pointing p-i-n diode which may achieve better switching results when these diodes are used with the R/W material in a 3D memory array.
Type:
Grant
Filed:
September 17, 2009
Date of Patent:
June 26, 2012
Assignee:
SanDisk 3D LLC
Inventors:
Abhijit Bandyopadhyay, Kun Hou, Steven Maxwell
Abstract: A memory cell including a first electrode, a second electrode and a first resistance-switching layer located between the first and second electrodes. The first resistance-switching layer comprises hafnium silicon oxynitride.
Type:
Application
Filed:
February 29, 2012
Publication date:
June 21, 2012
Applicant:
SanDisk 3D LLC
Inventors:
Tong Zhang, Timothy James Minvielle, 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 three-dimensional array especially adapted for memory elements that reversibly change a level of electrical conductance in response to a voltage difference being applied across them. Memory elements are formed across a plurality of planes positioned different distances above a semiconductor substrate. A two-dimensional array of bit lines to which the memory elements of all planes are connected is oriented vertically from the substrate and through the plurality of planes. A double-global-bit-line architecture provides a pair of global bit lines for each bit lines for accessing a row of memory elements in parallel. A first one of each pair allows the local bit lines of the row to be sensed while a second one of each pair allows local bit lines in an adjacent row to be set to a definite voltage so as to eliminate leakage currents between adjacent rows of local bit lines.
Abstract: A method of making a semiconductor device includes forming a first conductivity type polysilicon layer over a substrate, forming an insulating layer over the first conductivity type polysilicon layer, where the insulating layer comprises an opening exposing the first conductivity type polysilicon layer, and forming an intrinsic polysilicon layer in the opening over the first conductivity type polysilicon layer. A nonvolatile memory device contains a first electrode, a steering element located in electrical contact with the first electrode, a storage element having a U-shape cross sectional shape located over the steering element, and a second electrode located in electrical contact with the storage element.
Abstract: A non-volatile memory device contains a three dimensional stack of horizontal diodes located in a trench in an insulating material, a plurality of storage elements, a plurality of word lines extending substantially vertically, and a plurality of bit lines. Each of the plurality of bit lines has a first portion that extends up along at least one side of the trench and a second portion that extends substantially horizontally through the three dimensional stack of the horizontal diodes. Each of the horizontal diodes is a steering element of a respective non-volatile memory cell of the non-volatile memory device, and each of the plurality of storage elements is located adjacent to a respective steering element.
Type:
Grant
Filed:
October 15, 2010
Date of Patent:
May 29, 2012
Assignee:
SanDisk 3D LLC
Inventors:
Natalie Nguyen, Paul Wai Kie Poon, Steven J. Radigan, Michael Konevecki, Raghuveer S. Makala
Abstract: Methods in accordance with aspects of this invention form microelectronic structures in accordance with other aspects this invention, such as non-volatile memories, that include (1) a bottom electrode, (2) a resistivity-switchable layer disposed above and in contact with the bottom electrode, and (3) a top electrode disposed above and in contact with the resistivity-switchable layer; wherein the resistivity-switchable layer includes a carbon-based material and a dielectric filler material. Numerous additional aspects are provided.
Abstract: A nonvolatile memory device with a first conductor extending in a first direction and a semiconductor element above the first conductor. The semiconductor element includes a source, a drain and a channel of a field effect transistor (JFET or MOSFET). The nonvolatile memory device also includes a second conductor above the semiconductor element, the second conductor extending in a second direction. The nonvolatile memory device also includes a resistivity switching material disposed between the first conductor and the semiconductor element or between the second conductor and the semiconductor element. The JFET or MOSFET includes a gate adjacent to the channel, and the MOSFET gate being self-aligned with the first conductor.
Abstract: A method of making a device includes forming a first photoresist layer over an underlying layer, patterning the first photoresist layer to form a first photoresist pattern comprising a first grid, rendering the first photoresist pattern insoluble to a solvent, forming a second photoresist layer over the first photoresist pattern, patterning the second photoresist layer to form a second photoresist pattern over the underlying layer, where the second photoresist pattern is a second grid which overlaps the first grid to form a photoresist web, and etching the underlying layer using the photoresist web as a mask.
Abstract: In some aspects, a method of forming a memory cell is provided that includes (1) forming a steering element above a substrate; and (2) selectively forming a reversible resistance-switching element coupled to the steering element by: (a) forming a material layer on the substrate; (b) etching the material layer; and (c) oxidizing the etched material layer to form a reversible resistance-switching material. Numerous other aspects are provided.
Type:
Grant
Filed:
October 29, 2010
Date of Patent:
May 8, 2012
Assignee:
SanDisk 3D LLC
Inventors:
April D. Schricker, S. Brad Herner, Mark H. Clark