3D vertical NAND and method of making thereof by front and back side processing

Patent metadata

Field	Value
Publication number	US-RE45554-E
Application number	US-201414297298-A
Country	US
Kind code	E1
Filing date	Jun 5, 2014
Priority date	Apr 11, 2011
Publication date	Jun 9, 2015
Grant date	Jun 9, 2015

Abstract

Monolithic three dimensional NAND strings and methods of making. The method includes both front side and back side processing. Using the combination of front side and back side processing, a NAND string can be formed that includes an air gap between the floating gates in the NAND string. The NAND string may be formed with a single vertical channel. Alternatively, the NAND string may have a U shape with two vertical channels connected with a horizontal channel.

First claim

What is claimed is:

1. A method of making a monolithic three dimensional NAND string, comprising:
forming a stack of alternating layers of a first material and a second material over a substrate, wherein the first material comprises a conductive or semiconductor control gate material and wherein the second material comprises a first sacrificial material;
etching the stack to form a back side opening in the stack;
depositing a second sacrificial material in the back side openin…

Assignees

• Sandisk Technologies Inc

Inventors

• Alsmeier Johann

Classifications

• H10W10/021 Primary

  Electricity · mapped topic

• H10W10/20

  Electricity · mapped topic

• H10D30/693

  Electricity · mapped topic

• H10D30/689

  Electricity · mapped topic

• H10D84/016

  Electricity · mapped topic