公开(公告)号：JPH11121434A

公开(公告)日：1999-04-30

申请号：JP944998

申请日：1998-01-21

Applicant: UNITED MICROELECTRONICS CORP

Inventor： CHO GIGUN ,  RIN KENTEI ,  CHIN SHINRAI

IPC: H01L21/302 ,  H01L21/3065

Abstract: PROBLEM TO BE SOLVED: To provide an etching method which increases etching selectivity between oxide and metal silicide and simplifies the etching process itself. SOLUTION: An etching gas of the same composition and the same flow rate is used for a major etching process wherein an opening 50 is formed on an oxide layer 49 and for an over etching process. The etching gas contains CO. More specifically, the etching gas mixture that contains CHF3 , CF4 , argon and CO is used and the flow rate of each gas is 10-50, 10-50, 100-500 and 100-300 SCCM(standard cubic centimeter per minute).