銅単結晶(111)面の溶解に及ぼすヤング腐食液中の過硫酸アンモンおよびアンモニア水濃度の影響

Abstract

The effect of the concentration of (NH4)2S2O8 and NH4OH on dissolution of the copper (111) surface in Young’s etchant ((NH4)2S2O8-NH4OH-NH4Br) was studied by utilizing the etch-pits of edge dislocations. The dissolved thickness S of the matrix surface was first measured by two-beam interferometry. The two quantities H and D correlating with the dissolution of the copper (111) surface in lateral and normal directions at the dislocation sites were determined from S and the width h and depth d of the edge dislocation etch pit which were measured by replica electron microscopy.As the concentration of (NH4)2S2O8 and NH4OH in the etchants was increased, the following features were confirmed: (a) the lateral dissolution at the edge dislocation sites, H, increased gradually, (b) the normal dissolution at the edge dislocation site, D, showed a maximum at a certain concentration and (c) the matrix dissolution, S, increased slightly.These results were discussed on the basis of the two-dimensional nucleation theory of crystal dissolution.