US 6,664,161 B2 · Method and structure for salicide trench capacitor plate electrode

Abstract

The present invention is a method and structure for fabricating a trench capacitor within a semiconductor substrate having a buried plate electrode formed of metal silicide. A collar is formed in a trench etched into a substrate; a conformal metal film is deposited thereover, and is annealed to form a silicide that is self-aligned to the collar. Silicide will not be formed on the collar, pads and other areas where the silicon is not directly exposed and hence the metal layer can be removed from these areas by selective etching.

Claims11

Dependent claims

A method of fabricating a buried plate electrode within a trench cell capacitor of a semiconductor substrate, comprising:

forming a trench within said semiconductor substrate;
forming an oxide collar in an upper portion of said trench;
depositing a conformal metal film to cover a lower portion of said trench and said oxide collar;
annealing said semiconductor substrate to form a self-aligned silicide layer in said lower portion of said trench;
and
selectively removing all or portions of said conformal metal film from said oxide collar.

3 more elements

Dependencies are inferred from the claim text.

Facts

Application

10/137,268Filed 1 May 2002

Published

US 2003/0207532 A16 Nov 2003

Granted

16 Dec 2003

Term ends

Not estimatedThe source records don’t support an estimate.

Classification7 codes

H10D 1/047
Of capacitors having potential barriers, e.g. varactors: of conductor-insulator-semiconductor capacitors, e.g. trench capacitors
H10D 1/665
Conductor-insulator-semiconductor capacitors, e.g. MOS capacitors: trench conductor-insulator-semiconductor capacitors, e.g. trench MOS capacitors
H10B 12/038
Making the capacitor or connections thereto: the capacitor being in a trench in the substrate
H10B 12/0387
The capacitor being in a trench in the substrate: making the trench

Method and structure for salicide trench capacitor plate electrode

Life of this patent

Method and structure for salicide trench capacitor plate electrode

Life of this patent

Abstract

Claims11