The present application provides a kind of gas deposition device and substrate
processing method.The gas deposition device includes: reaction cavity, for carrying out gas
deposition process;Substrate support
assembly for carrying substrate, it is arranged below the reaction cavity;Gas
shower head is oppositely arranged with the substrate support
assembly, it is located above the reaction cavity, the substrate support
assembly and the gas
shower head between form a gas-filled space, the gas-filled space can be switched in
high pressure state and low pressure state;The upper surface of the substrate support assembly has the center area of carrying substrate and the edge area around the center area, the edge area and the lower surface of the gas
shower head opposite between during the gas
deposition process, there is
variable interval value, the interval value in the
high pressure state is less than the interval value in the low pressure state.The present application can guarantee step coverage and improve
processing efficiency.