Fabrication method of capacitor for integrated circuit

• US 6,204,111 B1
• Filed: 01/28/1999
• Issued: 03/20/2001
• Est. Priority Date: 12/28/1994
• Status: Expired due to Fees

• Current Assignee: Matsushita Electric Industrial Company Limited (Panasonic Holdings Corporation)
• Original Assignee: Matsushita Electric Corporation (Panasonic Holdings Corporation)
• Inventors: Fujii, Eiji, Uemoto, Yasuhiro, Arita, Koji, Shimada, Yasuhiro, Inoue, Atsuo, Nagano, Yoshihisa, Azuma, Masamichi, Izutsu, Yasufumi
• Primary Examiner(s): Bowers, Charles
• Assistant Examiner(s): Thompson, Craig
• Application Number:
  US09/238,157
• Time in Patent Office: 782 Days
• Field of Search: 438/239, 438/240-267, 438/800, 361/313
• US Class Current: 438/239
• CPC Class Codes: H01L 28/40 Capacitors
• CPC Class Codes: H01L 28/56 the dielectric comprising two or more layers, e.g. comprising buffer layers, seed layers, gradient layers
• CPC Class Codes: H10B 53/00 Ferroelectric RAM [FeRAM] devices comprising ferroelectric memory capacitors

Abstract

A method for fabricating a capacitor for an integrated circuit, comprising the steps of forming a titanium film for an adhesion layer over a substrate, forming a titanium dioxide film for a diffusion barrier layer by annealing the titanium film after ion-implantation of oxygen ion into a surface region of the titanium film so as to change titanium in the surface region to titanium dioxide, and forming a high dielectric constant capacitor on the titanium dioxide film.

Claims

1. A method for fabricating a capacitor for an integrated circuit comprising the steps of:

forming an adhesion layer of a metal and a diffusion barrier layer of a compound of said metal and a non-metal over a substrate by sputtering said metal continuously by using a target of said metal wherein a gas of said non-metal is induced at the time when a thickness of said adhesion layer reaches to a predetermined thickness;

forming a bottom electrode layer of a noble metal on said diffusion barrier layer;

forming a dielectric layer of a metal oxide on said bottom electrode layer;

forming a top electrode layer of a conductive metal on said dielectric layer;

etching said top electrode layer and dielectric layer selectively;

etching said bottom electrode layer selectively; and

etching said diffusion barrier layer and adhesion layer selectively.

2. The method of claim 1, wherein said sputtering is performed with changing an inducing amount of said gas.

3. The method of claim 1, wherein said gas comprises one selected from the group consisting of oxygen gas, nitrogen gas and a mixture of them.

4. The method of claim 1, wherein said adhesion layer comprises one of titanium and tantalum.