Patent · US Expired

Low haze wafer treatment process

US6037271A · kind A · utility

3Cited by
9References
15Claims
0Family size

Assignee

Inventors

Key dates

Filing dateOct 21, 1998
Grant dateMar 14, 2000
Priority date
Expiry dateOct 21, 2018

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH01L21/67051
  • WIPO fieldSemiconductors
  • WIPO sectorElectrical engineering

Abstract

A process for removing a plurality of layers of different materials from a substrate having a silicon material base, at least one of said layers being a silicon oxide material and at least one other of said layers comprising a metal and the metal layer being located above the silicon oxide layer. The process includes the steps of treating the substrate with a series of chemical formulations adapted to successively remove the materials of the plurality of layers until the silicon material base is exposed, the silicon oxide layer being removed by treatment with HF, wherein the HF treatment to remove said silicon oxide layer comprises exposing the substrate to: PA1 initially, a dilute HF solution of no more than 1.0% concentration; PA1 subsequently, a concentrated HF solution of from about 2.5% to about 10% concentration; and PA1 finally, a dilute HF solution of no more than 1.0% concentration.

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