Abstract: CVD diamond with high electrical, optical and thermal quality has been used in many applications. However,
its inert chemical nature and high temperature stability make it difficult to be processed. A highly available etching technique compatible with
existing diamond processing is desirable. In this paper, CVD diamond thick films were etched with rare-earth compound ink prepared by the authors. The etching
process is taken in the atmosphere at a temperature below the oxidation temperature of diamond. The technique uses inexpensive and safe rare-earth compound ink and the experimental results show that the processing is simple
and efficient for polishing the CVD diamond thick films rapidly. The results were studied by SEM.

Key words: CVD diamond thick film, etching, rare-earth compound ink