Patent ID: 8435380

Claim:
A substrate chucking unit comprising: a substrate supporting member including, a rotatable supporting plate configured to load a substrate thereon, and a plurality of chucking pins disposed at the supporting plate configured to space a substrate loaded on the supporting plate off a top surface of the supporting plate by supporting an edge part of the substrate from a side of the substrate, each of the chucking pins including magnetism at its lower end and configured to rotate the substrate; and a rotation adjustment unit disposed under the supporting plate for adjusting rotation of the chucking pins, the rotation adjustment unit including, at least one magnetic unit surrounding the supporting plate and adjacent to the magnetism, the at least one magnetic unit configured to adjust rotation of the pin rotation part by magnetic interaction with the magnetism; and a vertical actuation part configured to move the magnetic unit vertically, wherein the at least one magnetic unit includes a first magnetic unit having first polarity and a second magnetic unit having second polarity under the first magnetic unit, and the second magnetic unit is inserted into the first magnetic unit when the second magnetic unit is raised to the first magnetic unit by the vertical actuation part.