Chamber assembly, air inlet device and substrate processing equipment

The invention provides a cavity assembly. The cavity assembly comprises an annular lining assembly and an air inlet inserting piece. The bushing assembly comprises an upper bushing and a lower bushing; a plurality of layers of first air inlet structures are arranged on one side of the lower bush, each layer of first air inlet structure is divided into a plurality of first air inlet areas in the circumferential direction of the lower bush, and each first air inlet area comprises a plurality of first air inlet channels distributed in the circumferential direction of the lower bush; the air inlet plug-in is coupled to the lining assembly, multiple layers of second air inlet structures corresponding to the multiple layers of first air inlet structures are arranged in the air inlet plug-in, each layer of second air inlet structure is divided into multiple second air inlet areas in the horizontal direction, each second air inlet area comprises at least one second air inlet channel, and one second air inlet channel