In a process for manufacturing a semiconductor wafer, defect distribution state analysis is performed so as to facilitate identification of the defect cause including a device cause and a process cause by classifying the defect distribution state according to the defect position coordinates detected by the inspection device, into one of the distribution characteristic categories: repeated defects, clustered defects, arc-shaped regional defects, radial regional defects, line type regional defects, ring and blob type regional defects, and random defects.