▎ 摘　　要

NOVELTY - The method involves etching stop layer is prepared on a front surface of a sapphire substrate, and the etching stop material used in the etching stop layer does not absorb laser light with a preset wavelength. A laser with a preset wavelength is used to open the sapphire substrate at a preset position on a back of the sapphire substrate to prepare a through hole. A front surface process is completed on the etching stop layer of the sapphire substrate after the through hole is prepared to obtain a MMIC chip, and the etching stop layer corresponding to the through hole on the MMIC chip is removed to obtain the through hole. USE - Method for preparing through holes on a graphene-on-sapphire radio frequency MMIC chip. ADVANTAGE - The method of preparing a through hole will not cause damage to a dielectric layer or a device prepared by a front process, and a preparation process is simple. DESCRIPTION OF DRAWING(S) - The drawing shows a flow diagram illustrating a method for preparing through holes on a graphene-on-sapphire radio frequency MMIC chip. (Drawing includes non-English language text).