US 11,444,123 B2 · Selector transistor with metal replacement gate wordline

Abstract

A vertical transistor structure having a metal gate wordline. The vertical transistor structure can include an epitaxially grown semiconductor column surrounded by a thin gate dielectric layer. A gate structure can surround the semiconductor column and the gate dielectric layer. The device can include first and second dielectric layers and an electrically conductive metal layer located between the first and second dielectric layers. The electrically conductive metal of the gate structure can be tungsten (W). In addition, a thin layer of Ti or TiN can be formed between the metal gate layer and the first and second dielectric layers and the gate dielectric layer. The metal gate layer can be formed with or without the use of a sacrificial layer.

Claims18

Dependent claims

A method for manufacturing a memory array, the method comprising:

providing a semiconductor substrate;
depositing a first dielectric layer over the semiconductor substrate;
depositing a sacrificial layer over the first dielectric layer;
depositing a second dielectric layer over the sacrificial layer;
forming a plurality of vertical semiconductor columns in the sacrificial layer, the plurality of semiconductor columns extending to the substrate having a plurality of corresponding beveled recesses and each semiconductor column including a source and drain;
removing the sacrificial layer to form an open space adjacent to the semiconductor column;
depositing a protective and adhesion layer over the open space adjacent to the semiconductor column, the protective and adhesion layer coating the first dielectric layer and the second dielectric layer surrounding the open space;
and
filling the open space with an electrically conductive metal.

6 more elements

Dependencies are inferred from the claim text.

Selector transistor with metal replacement gate wordline

Life of this patent

Selector transistor with metal replacement gate wordline

Life of this patent

Abstract

Claims18