Sandisk Technologies Inc.

Sandisk 3d LLC

Naohito Yanagida

Michiaki Sano

Akira Nakada

Eiji Hayashi

Steven J Radigan

Kensuke Yamaguchi

Genta Mizuno

Hiroaki Iuchi

Keisuke Izumi

Akio Yanai

Cheng Feng

Takehiro Yamazaki

Minoru Yamaguchi

Teruyuki Mine

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

Contact openings extending to sacrificial layers located at different depths can be formed by sequentially exposing a greater number of openings in a mask layer by iterative alternation of trimming of a slimming layer over the mask layer and an anisotropic etch that recesses pre-existing contact openings by one level. In one embodiment, pairs of an electrically conductive via contact and electrically conductive electrodes can be simultaneously formed as integrated line and via structures. In another embodiment, encapsulated unfilled cavities can be formed in the contact openings by non-conformal deposition of a material layer, electrically conductive electrodes can be formed by replacement of portions of the sacrificial layers, and the electrically conductive via contacts can be subsequently formed on the electrically conductive electrodes. Electrically conductive via contacts extending to electrically conductive electrodes located at different level can be provided with self-aligned insulating liner.

Multiheight contact via structures for a multilevel interconnect structure

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

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

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Yokkaichi, Japan

Naohito Yanagida