A trench isolation structure in a semiconductor device is provided. Compressed gas within the spray paint canister serves as the propellant which expels the liquid paint out of the canister when the nozzle is actuated. When the reciprocating rotating shaft reciprocatingly rotates, a plurality of brush bristles of the brush portion reciprocatingly oscillates in a circumferential direction of the reciprocating rotating shaft. Each of the memory modules includes several memory devices coupled to a memory hub.