Abstract: A method for preparing a diamond is disclosed. The method includes: processing a substrate material of a substrate holder to obtain a surface that is easily separated from diamond films, using a plasma chemical vapor deposition method to form a diamond film layer on the surface of the substrate holder, the plasma chemical vapor deposition method using multi-energy source coupled plasma and, post-processing the diamond film layer to remove impurity material on the diamond surface and a nucleation layer and/or stress layer with inconsistent properties of a main body of the diamond film. The method has the advantages of controllable thickness, controllable quality, controllable cost, etc., and lays the foundation for diamond in the fields of cutting tools and heat sinks.

Abstract: The invention discloses a multi-set clamping fixture for diamond machining, which is used for machining diamonds. The clamping fixture includes a base shell, a lip ring, and a sealing ring. The upper end of the base shell is opened, the lip ring is arranged at the inner ring position of the base shell, an embedding groove is arranged at the inner ring position of the lip ring, the sealing ring is arranged in the embedding groove, a vacuum cavity is formed in the base shell, and the base shell is externally connected with a vacuum pumping pipeline. After the pavilion portion of a diamond to be machined is inserted into the lip ring and supported by the sealing ring, a vacuum cavity is formed in the base shell, the vacuum cavity is vacuumized by the external pipeline, and then the diamond is limited at the position of the lip ring to complete the clamping process. The lip ring is connected with the base shell in a detachable structure.