METHOD OF POLISHING OPPOSITE SURFACES OF SEMICONDUCTOR WAFER AND DEVICE THEREFOR

• Main Author: IWANO EIICHIRO
• Format: Patent
• Language: English
• Published: 29.06.1999
• Edition: 6
• Subjects: BASIC ELECTRIC ELEMENTS; DRESSING OR CONDITIONING OF ABRADING SURFACES; ELECTRIC SOLID STATE DEVICES NOT OTHERWISE PROVIDED FOR; ELECTRICITY; FEEDING OF GRINDING, POLISHING, OR LAPPING AGENTS; GRINDING; MACHINES, DEVICES, OR PROCESSES FOR GRINDING OR POLISHING; PERFORMING OPERATIONS; POLISHING; SEMICONDUCTOR DEVICES; TRANSPORTING

PROBLEM TO BE SOLVED: To provide a method of and a device for polishing opposite surfaces of a semiconductor wafer, which can prevent the occurrence of craw-track during lapping. SOLUTION: Since craw-track occurs at the initial stage of lapping, in order to restrain the occurrence thereof at this initial stage, an upper level block is lowered at a slight speed before the starting of a normal process (in which a wafer is actually polished), that is, from a position above a position where the upper level block is made into contact with a wafer, by 2 to 5 cm, and upper and lower level blocks including internal gears and a sun gear are rotated at a low speed at this stage, and substantially at the same time or before the upper level block makes contact with the wafer, lapping slurry is dripped on and sprayed over the wafer. Thereafter, the upper level block is lowered while being rotated, and accordingly, the upper level block makes contact with the wafer so that a normal process can be carried out, similar to a conventional method.