| 摘要 |
A wafer back grinding apparatus is provided to produce thickness precisely without affecting the rear side of a wafer as a first measuring unit and second measuring unit are separated from the surface of an axis of rotation in which the rear side and wafer are placed and measure distance. A wafer back grinding apparatus(1000) comprises a spin chuck(100), a grinding part(200), a first measuring unit(300), second measuring unit(400) and a thickness output unit(500). The spin chuck has a same central axis as the central axis of a wafer(10) which is placed so that the rear side is exposed. The spin chuck rotates the wafer. The grinding part grinds the rear side of the wafer placed in the spin chuck. The first measuring unit is positioned to be isolated with the rear side of the wafer in which grinding is made with the grinding part. The first measuring unit measures a first distance of the wafer backside in which grinding is made. The second measuring unit is positioned to be isolated with the spin chuck. The second measuring unit measures a second distance separated from the surface of the spin chuck. The first distance measured by the first measuring unit and the second distance measured by the second measuring unit are input to the thickness output unit. The thickness output unit produces the thickness of the wafer in which grinding is made by using the first distance and the second distance. |
