3514 The planarization measuring method for langasite single crystal

摘要

PURPOSE: A method for measuring flatness of a langasite(La3Ga5SiO14) single crystal is provided to measure accurately an MRR(Material Removal Rate) of a single crystal and reduce a cost for measuring the MRR by using a simple pattern process used in a semiconductor manufacturing process. CONSTITUTION: SiO2 of thickness of 1000 angstrom is deposited as a protective layer in order to measure flatness. A photo-resist is coated on the deposited SiO2 protective layer. The photo-resist is patterned. An etching process is performed by using a mixed material of HCl: 10H2O. An MRR is obtained by dividing a removed material of a polishing process into a predetermined time. Namely, the flatness of the etched langasite single crystal is measured by performing the etching process using the mixed material of HCl: 10H2O.