公开(公告)号：JP2000133631A

公开(公告)日：2000-05-12

申请号：JP24064799

申请日：1999-08-27

Applicant: ASHLAND INC

Inventor： HACKETT THOMAS B ,  HATCHER ZACH II

IPC: H01L21/306 ,  C09K13/04 ,  H01L21/311

Abstract: PROBLEM TO BE SOLVED: To augment the corrosion rate of a silicon nitride by a method wherein a composite semiconductor device is made to corrode in a heating water solution containing a silicon-containing composition easily soluble in a phospholic acid and a water corrosion solution. SOLUTION: The total number of particles is set at 100 particle/ml or less, and at the same time, the size of the particles is set at 0.5 μ or smaller to add the amount of about 16 to 500 ppm of an easily soluble silicon-containing composition, which is a hexafluorosilicic acid, to an electron-grade phospholic acid solution existing at ppm to ppb/l of a low level in metallic ions or an acid and a water corrosion solution at a temperature of 150 to 180 deg.C and a composite semiconductor device is corroded in a water solution. Accordingly, the corrosion rate and selectivity of a silicon nitride can be augmented by executing a corrosion operation in a heating corrosion bath containing a phospholic acid and a silicon-containing composition soluble easily in a corrosion bath.