| 摘要 |
PURPOSE:To prevent any crack and break from generating in the peripheral edge of a wafer by a method where in an annular groove is formed in advance in the outer peripheral surface of the wafer in the state of an ingot, grinding is performed from the back surface of the wafer and the outer peripheral edge of the wafer is formed into the chamfered configuration thereof. CONSTITUTION:Annular grooves 7 are formed in the outer peripheral surface of a cylindrical ingot 5 at the prescribed pitch using a grindstone 6. The sectional configuration of the grooves is formed into a U shape and the bottom thereof is formed into a curved-surface V shape. Then, an etching is performed on the outer peripheral surface to remove the strains due to processing and to respectively finish the groove surfaces into a curved surface. After that, the ingot is sliced in a thicknes of T at positions holding a groove 7 between the positions and wafers 8 are made. The wafer 8 and a grindstone 10 are made to mutually rotate using the grindstone 10 having the annular V-shaped grooves 9 in the outer periphery thereof, a chamfering is performed on the outer peripheral edges of the surface and back surface of the wafer and the outer peripheral edges are both finished into a curved-surface form. After the region for a device is formed on the surface of the wafer 8, grinding is performed from the back surface and when the wafer is made to the prescribed thickness (t), the outer peripheral edge 11 of the back surface appears in the chamfered form thereof. By this way, the starting points of cracks in the peripheral edge of the wafer are removed. As a result, a crack and a break are hardly generated. |
