Abstract: A nonvolatile memory cell includes a storage element, the storage element comprising a carbon material, a steering element located in series with the storage element, and a metal silicide layer located adjacent to the carbon material. A method of making a device includes forming a metal silicide over a silicon layer, forming a carbon layer over the metal silicide layer, forming a barrier layer over the carbon layer, and patterning the carbon layer, the metal silicide layer, and the silicon layer to form an array of pillars.
Abstract: A nonvolatile memory cell includes: a rail-shaped first conductor formed at a first height above a substrate; a rail-shaped second conductor formed above the first conductor; and a vertically oriented first pillar comprising a p-i-n first diode; wherein the first pillar is disposed between the second conductor and the first conductor; wherein the first diode comprises an intrinsic or lightly doped region; and wherein the intrinsic or lightly doped region has a first thickness of about 300 angstroms or greater. Numerous additional aspects are provided.
Abstract: A method is described for forming a nonvolatile one-time-programmable memory cell having reduced programming voltage. A contiguous p-i-n diode is paired with a dielectric rupture antifuse formed of a high-dielectric-constant material, having a dielectric constant greater than about 8. In preferred embodiments, the high-dielectric-constant material is formed by atomic layer deposition. The diode is preferably formed of deposited low-defect semiconductor material, crystallized in contact with a silicide. A monolithic three dimensional memory array of such cells can be formed in stacked memory levels above the wafer substrate.
Abstract: A nonvolatile memory cell including at least two two-terminal non-linear steering elements arranged in series, and a resistivity switching storage element arranged in series with the at least two two-terminal non-linear steering elements. A memory array, comprising a plurality of the nonvolatile memory cells is also described. A method of forming a nonvolatile memory cell is also described.
Abstract: A method of making a device includes forming at least one anodizable metal layer over at least one of an electrode or a semiconductor device, forming a plurality of pores in the anodizable metal layer by anodization of the anodizable metal layer to expose a portion of the electrode or semiconductor device, and filling at least one pore with a rewritable material such that at least some of the rewritable material is in electrical contact with the electrode or semiconductor device.
Abstract: A nonvolatile memory device includes at least one memory cell which comprises a first diode portion, a second diode portion and an antifuse separating the first diode portion from the second diode portion.
Abstract: A substantially planar surface coexposes conductive or semiconductor features and a dielectric etch stop material. A second dielectric material, different from the dielectric etch stop material, is deposited on the substantially planar surface. A selective etch etches a hole or trench in the second dielectric material, so that the etch stops on the conductive or semiconductor feature and the dielectric etch stop material. In a preferred embodiment the substantially planar surface is formed by filling gaps between the conductive or semiconductor features with a first dielectric such as oxide, recessing the oxide, filling with a second dielectric such as nitride, then planarizing to coexpose the nitride and the conductive or semiconductor features.
Type:
Grant
Filed:
August 3, 2010
Date of Patent:
August 30, 2011
Assignee:
SanDisk 3D LLC
Inventors:
Samuel V. Dunton, Christopher J. Petti, Usha Raghuram
Abstract: Circuits and methods are described for decoding exemplary memory arrays of programmable and, in some embodiments, re-writable passive element memory cells, which are particularly useful for extremely dense three-dimensional memory arrays having more than one memory plane. In addition, circuits and methods are described for selecting one or more array blocks of such a memory array, for selecting one or more word lines and bit lines within selected array blocks, for conveying data information to and from selected memory cells within selected array blocks, and for conveying unselected bias conditions to unselected array blocks.
Abstract: Nonvolatile memory cells and methods of forming the same are provided, the methods including forming a first conductor at a first height above a substrate; forming a first pillar-shaped semiconductor element above the first conductor, wherein the first pillar-shaped semiconductor element comprises a first heavily doped layer of a first conductivity type, a second lightly doped layer above and in contact with the first heavily doped layer, and a third heavily doped layer of a second conductivity type above and in contact with the second lightly doped layer, the second conductivity type opposite the first conductivity type; forming a first dielectric antifuse above the third heavily doped layer of the first pillar-shaped semiconductor element; and forming a second conductor above the first dielectric antifuse.
Abstract: Apparatus and systems are provided for thermal regulation of a memory integrated circuit (“IC”). The apparatus and systems may include a thermal sensor on a memory IC, and a heating element coupled to the thermal sensor. The heating element is adapted to heat the memory IC in response to a signal from the thermal sensor. Other aspects are also provided.
Abstract: A method is described for monolithically forming a first memory level above a substrate, the method including: (a) forming a plurality of first substantially parallel, substantially coplanar conductors above the substrate, the first conductors extending in a first direction; (b) forming a plurality of vertically oriented contiguous p-i-n diodes above the first conductors, the contiguous p-in diode comprising semiconductor material crystallized in contact with a silicide, silicide-germanide, or germanide layer; (c) forming a plurality of second substantially parallel, substantially coplanar conductors, the second conductors above the contiguous p-i-n diodes, the second conductors extending in a second direction different from the first direction, each contiguous p-i-n diode vertically disposed between one of the first conductors and one of the second conductors; (d) and forming a plurality of dielectric rupture antifuses, each dielectric rupture antifuse disposed between one of the contiguous p-i-n diodes and
Abstract: A semiconductor device comprising a bipolar transistor having a base region, an emitter region and a collector region, wherein the base region comprises polycrystalline semiconductor material formed by crystallizing silicon, germanium or silicon germanium in contact with a silicide, germanide or silicide germanide is described. The emitter region and collector region also may comprise polycrystalline semiconductor material formed by crystallizing silicon, germanium or silicon germanium in contact with a silicide, germanide or silicide germanide forming metal. The polycrystalline semiconductor material is preferably silicided polysilicon, which is formed in contact with C49 phase titanium silicide.
Abstract: Methods and apparatus are described that develop a reference voltage that is based on a difference between a threshold voltage of a first transistor and a threshold voltage of a second transistor, and further based on a difference between a gate overdrive voltage of the first transistor and a gate overdrive voltage of the second transistor.
Abstract: A technique for identifying bad pages of storage elements in a memory device. A flag byte is provided for each page group of one or more pages which indicates whether the page group is healthy. Flag bytes of selected page groups also indicate whether larger sets of page groups are healthy, according to bit positions in the flag bytes. A bad page identification process includes reading the flag bytes with a selected granularity so that not all flag bytes are read. Optionally, a drill down process reads flag bytes for smaller sets of page groups when a larger set of page groups is identified as having at least one bad page. This allows the bad page groups to be identified and marked with greater specificity. Redundant copies of flag bytes may be stored in different locations of the memory device. A majority vote process assigns a value to each bit.
Abstract: A method for fabricating a 3-D monolithic memory device. Silicon-oxynitride (SixOyNz) on amorphous carbon is used an effective, easily removable hard mask with high selectivity to silicon, oxide, and tungsten. A silicon-oxynitride layer is etched using a photoresist layer, and the resulting etched SixOyNz layer is used to etch an amorphous carbon layer. Silicon, oxide, and/or tungsten layers are etched using the amorphous carbon layer. In one implementation, conductive rails of the 3-D monolithic memory device are formed by etching an oxide layer such as silicon dioxide (SiO2) using the patterned amorphous carbon layer as a hard mask. Memory cell diodes are formed as pillars in polysilicon between the conductive rails by etching a polysilicon layer using another patterned amorphous carbon layer as a hard mask. Additional levels of conductive rails and memory cell diodes are formed similarly to build the 3-D monolithic memory device.
Type:
Grant
Filed:
March 30, 2010
Date of Patent:
August 9, 2011
Assignee:
SanDisk 3D LLC
Inventors:
Steven J. Radigan, Michael W. Konevecki
Abstract: A non-volatile memory cell includes a first electrode, a steering element, a storage element located in series with the steering element, a plurality of discrete conductive nano-features separated from each other by an insulating matrix, where the plurality of discrete nano-features are located in direct contact with the storage element, and a second electrode. An alternative non-volatile memory cell includes a first electrode, a steering element, a storage element located in series with the steering element, a plurality of discrete insulating nano-features separated from each other by a conductive matrix, where the plurality of discrete insulating nano-features are located in direct contact with the storage element, and a second electrode.
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: 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. Bit lines to which the memory elements of all planes are connected are oriented vertically from the substrate and through the plurality of planes.
Abstract: A rewritable nonvolatile memory cell is disclosed comprising a steering element in series with a carbon nanotube fabric. The steering element is preferably a diode, but may also be a transistor. The carbon nanotube fabric reversibly changes resistivity when subjected to an appropriate electrical pulse. The different resistivity states of the carbon nanotube fabric can be sensed, and can correspond to distinct data states of the memory cell. A first memory level of such memory cells can be monolithically formed above a substrate, a second memory level monolithically formed above the first, and so on, forming a highly dense monolithic three dimensional memory array of stacked memory levels.
Abstract: A monolithic three dimensional semiconductor device structure includes a first layer including a first occurrence of a first reference mark at a first location, and a second layer including a second occurrence of the first reference mark at a second location, wherein the second location is substantially directly above the first location. The device structure also includes an intermediate layer between the first layer and the second layer, the intermediate layer including a blocking structure, wherein the blocking structure is vertically interposed between the first occurrence of the first reference mark and the second occurrence of the first reference mark. Other aspects are also described.
Type:
Grant
Filed:
May 22, 2009
Date of Patent:
July 19, 2011
Assignee:
SanDisk 3D LLC
Inventors:
Yung-Tin Chen, Christopher J. Petti, Steven J. Radigan, Tanmay Kumar