Patent · US Expired

Methods of cleaning surfaces of copper-containing materials, and methods of forming openings to copper-containing substrates

US6541391B2 · kind B2 · utility

8Cited by
16References
25Claims
0Family size

Assignee

Inventors

Key dates

Filing dateFeb 28, 2001
Grant dateApr 1, 2003
Priority date
Expiry dateMar 29, 2021

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC11D2111/22
  • WIPO fieldBasic materials chemistry
  • WIPO sectorChemistry

Abstract

The invention includes a semiconductor processing method of cleaning a surface of a copper-containing material by exposing the surface to a mixture having a basic pH and comprising Cl−, NO3− and F−. The invention also includes a semiconductor processing method of forming an opening to a copper-containing substrate. Initially, a mass is formed over the copper-containing substrate. The mass comprises at least one of a silicon nitride and a silicon oxide. An opening is etched through the mass and to the copper-containing substrate. A surface of the copper-containing substrate defines a base of the opening, and is referred to as a base surface. The base surface of the copper-containing substrate is at least partially covered by at least one of a copper oxide, a silicon oxide or a copper fluoride. The base surface is cleaned with a cleaning solution comprising hydrochloric acid, nitric acid and hydrofluoric acid to remove at least some of the at least one of a copper oxide, a silicon oxide or a copper fluoride from over the base surface. The cleaning solution comprises a pH of at least 7.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.