▎ 摘　　要

NOVELTY - Manufacturing a microfluidic inertial switch based on graphene-coated gallium-based alloy droplets involves using graphene with high lubricity and high conductivity to perform the gallium-based alloy droplets, where coating effectively avoid the adhesion of the gallium-based alloy oxide layer to the surface of the microchannel in the switch, while maintains the good conductivity of the droplet. The manufacturing method involves making graphene-coated gallium-based alloy droplets, then using a micro-injector to drop the gallium-based alloy into a petri dish covered with graphene powder, and shaking the petri dish to make the gallium-based alloy droplet roll fully in the graphene powder, and coating gallium-based alloy droplet on the surface of the gallium-based alloy droplet with a dense and uniform graphene. USE - Method for manufacturing a microfluidic inertial switch based on graphene-coated gallium-based alloy droplets. ADVANTAGE - The method enables to manufacture a microfluidic inertial switch based on graphene-coated gallium-based alloy droplets, which has high lubricity and high conductivity to coat gallium-based alloy droplets, which effectively avoid the adhesion of the oxide layer of the gallium-based alloy to the surface of the microchannel in the switch, and has good conductive properties of the droplets. DETAILED DESCRIPTION - The cover glass is made with fixed electrodes, and magnetron sputtering a layer of chromium film and a layer of gold film are applied on the glass sheet in sequence, where the chromium film is used as an adhesion layer to improve the bonding strength between the gold film and the glass sheet, then a layer of positive photoresist is spin-coated on the gold film using a homogenizer, and after the spin coating is completed, pre-baking, exposure, development and post-baking are performed in sequence. The wet etching is performed on the gold film and the chromium film in sequence, then removing the remaining photoresist on the surface of the gold film and making Poly(dimethylsiloxane) (PDMS) substrates containing microchannels, and using photolithography process to fabricate the SU-8 negative photoresist structure on the surface of the silicon wafer to obtain the SU-8 mold. The microchannel structure on the SU-8 mold is copied to the surface of the PDMS substrate using the casting process, then, due to the certain viscosity of the PDMS surface, in order to prevent the graphene coated on the surface o tfhe gallium-based alloy droplets from being stuck to On the surface of the PDMS microchannel, cover the area outside the microchannel structure on the PDMS surface with a polyimide (PI) film, and deposit a layer of parylene (Parylene) film on the sidewall and bottom of the microchannel by chemical vapor deposition as a protective film. The cover glass and PDMS substrate are bonded and the surface of the glass cover sheet and the PDMS substrate are treated with oxygen plasma, and then, the graphene-coated gallium-based alloy droplets are put into the microchannel. A microscope is used to align and paste the cover glass and PDMS substrate together to complete the bonding of the two.