Thinning technology of MgO substrate for diamond growth by laser slicing

Abstract

We tried laser slicing of (100) MgO wafer used as a substrate for heteroepitaxial growth of single crystal diamond. The laser slicing was successful by irradiating the inside of the material with an ultrashort pulse laser and generating a {100} cleavage. However, it was clarified that the cleavage of {100} was excessively extended and deviated from the slicing surface, so that steps of 20 μm were formed on the peeled surface. In order to reduce the kerf-loss, it was necessary to control the cleavage of {100}. Therefore, we proposed a scanning method to control cleavage and its extension. As a result, we succeeded in slicing a 2-inch MgO wafer with a kerf-loss of 30 μm.

Keywords

• laser slicing
• mgo
• diamond
• semiconductor
• ultrashort pulse laser