The damage of sawn, lapped, etched and polished wafers was evaluated by the angle lapping method and a biaxial fracture strength test. The Si wafers for analysis were fabricated by the commercial wafering process. As the wafering process proceeded, the depth of damage (DOD) measured by the angle lapping method decreased but the fracture strength measured by the ring-on-ring test increased. As a result, a correlation between DOD and fracture strength was verified using an equation for the fracture toughness, KIC. The fracture strength obtained from the ring-on-ring test was found to be one of the representative values for the mechanical properties of a wafer as it passed through the wafering process.

Keywords: depth of damage, angle lapping method, silicon wafer, fracture strength, ring-on-ring test