US 2022/0102378 A1 · MICROELECTRONIC AND SEMICONDUCTOR DEVICES WITH A TUNNELING STRUCTURE FREE OF HIGH- k MATERIAL BY A SELECT GATE STRUCTURE, AND RELATED METHODS

Abstract

A vertical structure extends through a tiered structure of alternating conductive and insulative materials. The vertical structure includes a channel structure and a tunneling structure. At least one of the conductive materials of the tiered structure provides a select gate tier (e.g., including a control gate for a select gate drain (SGD) transistor). Adjacent the select gate tier of the tiered structure, the tunneling structure consists of or consists essentially of an oxide-only material. Adjacent the word line tiers of the tiered structure, the tunneling structure comprises at least one material that is other than an oxide-only material, such as a nitride or oxynitride. The oxide-only material adjacent the select gate tier may inhibit unintentional loss of charge from a neighboring charge storage structure, which may improve the stability of the threshold voltage (Vth) of the select gate tier.

Claims23

Dependent claims

A microelectronic device, comprising:

a stack structure comprising insulative structures interleaved with conductive structures;
at least one select gate structure over the stack structure;
a first tunneling structure extending vertically through the stack structure, the first tunneling structure comprising a high-κ material;
a second tunneling structure extending vertically through the at least one select gate structure, the second tunneling structure being devoid of the high-κ material;
and
a channel structure extending vertically through the stack structure and the at least one select gate structure, the channel structure being horizontally interior to the first tunneling structure and the second tunneling structure,
the channel structure comprising:
a first channel portion;
and
a second channel portion above the first channel portion,
the first channel portion differing from the second channel portion in at least one of a thickness of a semiconductor material, a horizontal outer dimension of the semiconductor material, and a composition of the semiconductor material.

8 more elements

A method of forming a semiconductor device, the method comprising:

forming an opening extending through a tiered material structure comprising an insulative material interleaved with an other material;
forming a charge-blocking material in the opening along a sidewall of the tiered material structure;
forming a charge storage material in the opening along a sidewall of the charge-blocking material;
forming a tunneling structure, comprising:
forming a high-κ material in the opening along a sidewall of the charge storage material;
oxidizing only a portion of the high-κ material to convert the portion of the high-κ material into an oxide material, to form a first portion of the tunneling structure comprising the high-κ material, and to form a second portion of the tunneling structure consisting essentially of oxide material comprising the oxide material formed from the portion of the high-κ material, the second portion of the tunneling structure being substantially free of the high-κ material and being above the first portion of the tunneling structure;
and
forming a channel structure, comprising:
forming a channel material in the opening along a sidewall of the tunneling structure, the channel structure comprising a first channel portion along a sidewall of the first portion of the tunneling structure and comprising a second channel portion along a sidewall of the second portion of the tunneling structure,
the channel material of the first channel portion differing in at least one of thickness, horizontal outer dimension, and composition from the channel material of the second channel portion.

7 more elements

Dependencies are inferred from the claim text.

MICROELECTRONIC AND SEMICONDUCTOR DEVICES WITH A TUNNELING STRUCTURE FREE OF HIGH- k MATERIAL BY A SELECT GATE STRUCTURE, AND RELATED METHODS

Life of this patent

MICROELECTRONIC AND SEMICONDUCTOR DEVICES WITH A TUNNELING STRUCTURE FREE OF HIGH- k MATERIAL BY A SELECT GATE STRUCTURE, AND RELATED METHODS

Life of this patent

Abstract

Claims23