METHOD FOR CHEMICALLY ETCHING MN-ZN FERRITE

摘要

PURPOSE:To provide high dimensional accuracy and superior surface roughness to the mirror-polished single crystal face of Mn-Zn ferrite by chemical etching by bringing a phosphoric acid-base aqueous soln. having a relatively low concn. into contact with the single crystal face. CONSTITUTION:The (100) single crystal face of Mn-Zn ferrite is mirror polished with diamond abrasive grains, and the ferrite is annealed at >=700 deg.C in an atmosphere contg. oxygen at the equilibrium concn. of oxygen in the ferrite or below. A phosphoric acid-base aqueous soln. contg. at least 20wt%, preferably <=about 95% water is then brought into contact with the mirror-polished single crystal face preferably by immersing the ferrite in the soln. and allowing it to stand. The single crystal face is chemically etched to obtain an etched face having high deimensional accuracy and superior surface roughness.