Sandisk Technologies Inc.

Sandisk 3d LLC

Ming-Che Wu

Tanmay Kumar

Yung-Tin Chen

Juan Pablo Saenz

Guangle Zhou

Deepak Kamalanathan

Wei-Te Wu

Peter Rabkin

Tim Minvielle

Federico Nardi

Srikanth Ranganathan

Chuanbin Pan

Zhaoqiang Bai

Alvaro Padilla

Sebastian J M Wicklein

Tim Chen

The switching device includes three terminals including an inner surface, an oxide layer on the inner surface of the third terminal, and a chalcogenide pillar extending through the oxide layer and the third terminal, the pillar being in electrical communication with the first terminal and the second terminal, wherein the voltage difference between the first terminal and the second terminal changes the channel from a first state to a second state when a threshold voltage between the first terminal and the second terminal is exceeded, the threshold voltage being dependent on temperature. The third terminal is resistive and receives a control signal to apply heat to the pillar and modulate the threshold voltage. The switching device can be used to select the memory stack through the bitline and provide a nearly limitless current based on the threshold switching conduction providing avalanche current conduction through the switching device.

Threshold switch for memory

A resistive memory device, such as a BMC ReRAM device, includes at least one resistive memory element which contains a carbon barrier material portion and a resistive memory material portion that is disposed between a first electrode and a second electrode.

Resistive memory device containing carbon barrier and method of making thereof

A method is provided that includes forming a word line above a substrate, the word line disposed in a first direction, forming a bit line above the substrate, the bit line disposed in a second direction perpendicular to the first direction, forming a nonvolatile memory material between the word line and the bit line, the nonvolatile memory material including a semiconductor material layer and conductive oxide material layer, forming a first barrier material layer between the word line and the nonvolatile memory material, forming a second barrier material layer between the bit line and the nonvolatile memory material, and forming a memory cell including the nonvolatile memory material at an intersection of the bit line and the word line.

Methods and apparatus for three-dimensional nonvolatile memory

A method is provided that includes forming a word line above a substrate, the word line disposed in a first direction, forming a bit line above the substrate, the bit line disposed in a second direction perpendicular to the first direction, forming a nonvolatile memory material between the word line and the bit line, and forming a memory cell including the nonvolatile memory material at an intersection of the bit line and the word line. The word line includes a first portion and a second portion including an electrically conductive carbon-containing material. The nonvolatile memory material includes a semiconductor material layer and a conductive oxide material layer, with the semiconductor material layer disposed adjacent the second portion of the word line.

Systems and methods for providing a Barrier Modulated Cell (BMC) structure that may comprise a reversible resistance-switching memory element within a memory array are described. The BMC structure may include a barrier layer comprising a layer of amorphous germanium or amorphous silicon germanium paired with a conductive metal oxide, such as titanium dioxide (TiO2), strontium titanate (SrTiO3), or a binary metal oxide. The BMC structure may include a conductive metal oxide in series with an amorphous layer of a low bandgap material. The low bandgap material may comprise a semiconductor material with a bandgap energy (Eg) less than 1.0 eV. The improved BMC structure may be used for providing multi-level memory elements within a three dimensional memory array.

Low power barrier modulated cell for storage class memory

A method is provided that includes forming a word line above a substrate, forming a bit line above the substrate, forming a nonvolatile memory material between the word line and the bit line, the nonvolatile memory material including a semiconductor material layer and a conductive oxide material layer, forming a barrier material layer between the semiconductor material layer and the conductive oxide material layer, and forming a memory cell including the nonvolatile memory material at an intersection of the bit line and the word line. The word line is disposed in a first direction, the bit line is disposed in a second direction perpendicular to the first direction. The barrier material layer has an ionic conductivity of greater than about 0.1 Siemens/cm @ 1000&#xb0; C.

A resistive memory device includes a first electrode, a sidewall spacer electrode located on a sidewall of a dielectric material contacting the first electrode, a resistive memory cell containing a resistive memory material and contacting the sidewall spacer electrode, and a second electrode containing the resistive memory cell.

Resistive memory device having sidewall spacer electrode and method of making thereof

A multiple junction thin film transistor (TFT) is disclosed. The body of the TFT may have an n+ layer residing in a p&#x2212; region of the body. The TFT may have an n+ source and an n+ drain on either side of the p&#x2212; region of the body. Thus, the TFT has an n+/p&#x2212;/n+/p&#x2212;/n+ structure in this example. The n+ layer in the p&#x2212; region increases the breakdown voltage. Also, drive current is increased. The impurity concentration in the n+ layer in the p&#x2212; body and/or thickness of the n+ layer in the p&#x2212; body may be tuned to increase performance of the TFT. In an alternative, the body of the TFT has a p+ layer residing in an n&#x2212; region of the body. The TFT may have a p+ source and a p+ drain on either side of the p&#x2212; region of the body.

Multiple junction thin film transistor

Methods for forming a dual gate structure for a vertical TFT are described. The dual gate structure may be formed by performing a first etching process that includes forming a first set of trenches by etching a first set of oxide pillars to a first depth and forming a second set of trenches by etching a second set of oxide pillars to a second depth higher than the first depth, forming a first set of gate structures within the first set of trenches, forming a second set of gate structures within the second set of trenches, performing a second etching process that includes forming a third set of trenches by etching the first set of gate structures from a second initial depth to a third depth and forming a fourth set of trenches by etching the second set of gate structures to a fourth depth higher than the third depth.

Dual gate structure

A vertically oriented thin film transistor (TFT) having a tunnel barrier is disclosed. The tunnel barrier may be formed from a dielectric such as silicon oxide or hafnium oxide. The vertically oriented TFT selection device with tunnel barrier may serve as a selection device in a 3D memory array. The vertically oriented TFT may be used to connect/disconnect a global bit line to/from a vertical bit line in a 3D memory array. The vertically oriented TFT may be used to connect/disconnect a source line to/from a channel of a vertical NAND string in a 3D memory array. A vertical TFT with tunnel barrier has a high breakdown voltage, low leakage current, and high on current. The tunnel barrier can be at the top junction or bottom junction of the TFT.

Vertical TFT with tunnel barrier

A three-dimensional nonvolatile memory array includes a select layer that selectively connects vertical bit lines to horizontal bit lines. Individual select switches of the select layer include two separately controllable transistors that are connected in series between a horizontal bit line and a vertical bit line. Each transistor in a select switch is connected to a different control circuit by a different select line.

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San Jose, CA, United States of America

Ming-Che Wu