Patent ID: 7276118

Claim:
Spin-coating apparatus comprising: a spin-chuck; a baffle plate disposed under the spin chuck and extending radially outwardly thereof to collect and discharge a residue dispersed outwardly when a substrate held by the spin chuck is spin-coated, said baffle plate having a peripheral surface; and a clamping plate having a peripheral surface, the baffle plate being seated on the clamping plate with the peripheral surfaces of the plates facing each other, and wherein one of said baffle and clamping plates has a plurality of first bosses protruding radially from the peripheral surface thereof, and the other of said baffle and clamping plates has a plurality of first locking grooves extending therein and open at the peripheral surface thereof, each of the first bosses being received in a respective one of the first locking grooves, and each of the first locking grooves having an upper portion that is open at a top of the peripheral surface in which the locking groove extends, and a lower portion that is wider than the upper portion in a circumferential direction of the baffle and clamping plates, whereby the bosses can be inserted into the locking grooves through the upper portions of the locking grooves, respectively, as the baffle plate is being seated on the clamping plate, and whereby the baffle plate can be rotated relative to the clamping plate when seated thereon to lock the bosses within the grooves and thereby prevent the baffle plate from moving upwardly relative to the clamping plate.