Sandisk Technologies Inc.

Sandisk 3d LLC

Akira Nakada

Michiaki Sano

Naohito Yanagida

Manabu Hayashi

Tetsuya Yamada

Eiji Hayashi

Yusuke Yoshida

Sung Tae Lee

Akio Nishida

Steven J Radigan

Seje Takaki

Kensuke Yamaguchi

Hiroaki Iuchi

Kazutaka Yoshizawa

Kengo Kajiwara

Sayako Nagamine

Ryousuke Itou

Zhen Chen

Xiaolong Hu

Takashi Matsubara

Motoki Kawasaki

Takuro Maede

Takashi Kashimura

Shigenori Sato

Cheng Feng

Teruyuki Mine

Yasuke Oda

A wedge-shaped contact region can be employed to provide electrical contacts to multiple electrically conductive layers in a three-dimensional device structure. A cavity including a generally wedge-shaped region and a primary region is formed in a dielectric matrix layer over a support structure. An alternating stack of insulating layers and electrically conductive layers is formed by a series of conformal deposition processes in the cavity and over the dielectric matrix layer. The alternating stack can be planarized employing the top surface of the dielectric matrix layer as a stopping layer. A tip portion of each electrically conductive layer within remaining portions of the alternating stack is laterally offset from the tip of the generally wedge-shaped region by a respective lateral offset distance along a lateral protrusion direction. Contact via structures can be formed on the tip portions of the electrically conductive layers to provide electrical contact.

Three-dimensional devices with wedge-shaped contact region and method of making thereof

A three dimensional ReRAM device includes an etch stop dielectric material layer overlying top surfaces of the dielectric rail structures and the dielectric pillar structures. The etch stop dielectric material layer includes openings in areas that overlie semiconductor pillars of the vertical select transistors. An array of metal nitride portions is located within the openings in the etch stop dielectric material layer. The etch stop dielectric material layer protects the underlying dielectric pillar structures during anisotropic etching steps without covering the metal nitride portions.

Resistive memory device containing etch stop structures for vertical bit line formation and method of making thereof

A method is provided that includes forming a dielectric material above a substrate, forming a hole in the dielectric material, the hole disposed in a first direction, forming a word line layer above the substrate via the hole, the word line layer disposed in a second direction perpendicular to the first direction, forming a nonvolatile memory material on a sidewall of the hole, forming a local bit line in the hole, and forming a memory cell including the nonvolatile memory material at an intersection of the local bit line and the word line layer.

Methods and apparatus for vertical bit line structures in three-dimensional nonvolatile memory

A method is provided that includes forming a transistor by forming a first a rail gate disposed in a first direction above a substrate, forming a second rail gate disposed in a second direction above the substrate, the second direction perpendicular to the first direction, and forming a bridge section disposed between the first rail gate and the second rail gate.

Vertical thin film transistors with surround gates

An alternating stack of electrically conductive layers and electrically insulating layers is formed over global bit lines formed on a substrate. The alternating stack is patterned to form a line stack of electrically conductive lines and electrically insulating lines. Trench isolation structures are formed within each trench to define a plurality of memory openings laterally spaced from one another by the line stack in one direction and by trench isolation structures in another direction. The electrically conductive lines are laterally recessed relative to sidewall surfaces of the electrically insulating lines. A read/write memory material is deposited in recesses, and is anisotropically etched so that a top surface of a global bit line is physically exposed at a bottom of each memory opening. An electrically conductive bit line is formed within each memory opening to form a resistive random access memory device.

Concave word line and convex interlayer dielectric for protecting a read/write layer

A contact via cavity can be filled with a lower structure and an upper structure. The lower structure can be a conductive structure that is formed by depositing a conformal conductive material, and subsequently removing an upper portion of the conformal conductive material. A disposable material portion can be formed at a bottom of the cavity to protect the bottom portion of the conformal conductive layer during removal of the upper portion. After removal of the disposable material, at least one conductive material can fill the remainder of the cavity to form the upper structure. The upper structure and the lower structure collectively constitute a contact via structure. Alternatively, the lower structure can be a dielectric spacer with an opening therethrough. The upper structure can be a conductive structure that extends through the dielectric spacer, and provides an electrically conductive vertical connection.

Composite contact via structure containing an upper portion which fills a cavity within a lower portion

A fabrication process for a vertical channel transistor provides a desired control gate-to-drain overlap and sufficient isolation between the control gate and an underlying metal line. A body of the transistor is formed on a metal line, such as in a pillar shape. The metal line is oxidized to form metal oxide regions having an expanded volume. A gate insulator material and a control gate material are then deposited. The resulting structure is etched to form separate control gates for each transistor, and to expose the metal oxide. A further etch is performed to remove the metal oxide, forming voids under and around the control gates. An insulation fills the voids. An example implementation is a vertical bit line memory device in which the transistors connect a vertical bit line to a horizontal bit line.

Method for forming oxide below control gate in vertical channel thin film transistor

Non-volatile storage devices and methods for fabricating non-volatile storage device are described. Sidewalls of the memory cells and their associated word line may be covered with silicon oxide. Silicon nitride covers the silicon oxide adjacent to the word lines, which may provide protection for the word lines during fabrication. However, silicon nitride can trap charges, which can degrade operation if the trapped charges are near a charge trapping region of a memory cell. Thus, the silicon nitride does not cover the silicon oxide adjacent to charge storage regions of the memory cells, which can improve device operation. For example, memory cell current may be increased. Techniques for forming such a device are also disclosed. One aspect includes a method that uses a sacrificial material to control formation of a silicon nitride layer when forming a memory device.

Non-volatile storage having oxide/nitride sidewall

A method of forming sidewall gates for vertical transistors includes depositing a gate dielectric layer over polysilicon channel structures, and depositing a gate polysilicon layer over the gate dielectric. The gate polysilicon layer is then etched back to form separated gate electrodes. Filler portions are then formed between gate electrodes, which are then etched from the top down while their sides are protected.

Methods of forming sidewall gates

Growing community of inventors

Yokkaichi, Japan

Akira Nakada