WAFER HAVING THIN FILM OF MULTIPLE THICKNESS

摘要

PURPOSE: A wafer having a thin film of multiple thickness is provided to perform a function of the wafer for WRM(Working Reference Material) by forming the thin film having various thickness on one wafer. CONSTITUTION: A thin film is formed on a wafer. The thin film is formed by performing a CVD(Chemical Vapor Deposition) process and a diffusion process. The wafer having the thin film of multiple thickness can be formed by dipping vertically the erected wafer into an etching solution. The wafer is dipped as much as predetermined width(Tn) into the etching solution. The wafer is dipped as much as the predetermined width(Tn to T1) into the etching solution after a predetermined time. Each thickness(Ln to L1) of widths(Tn to T1) of the wafer is determined by the dipping time(D1 to Dn) of each width(Tn to T1) of the wafer dipped into the etching solution. The width(T0) is not etched since the width(T0) is not dipped into the etching solution.