METHOD FOR RECYCLING WAFER
A method for recycling a wafer is provided. The method removes residues remaining on the wafer separated from a semiconductor layer, using HCl and Cl 2 gases under high temperature and low pressure conditions. According to the method, damage of a surface of the wafer is minimized. In addition, since reduction in thickness and an outer diameter of the wafer is minimized, a number of attempts at reprocessing the wafer may be increased.
1 . A method for recycling a wafer, comprising:
removing residues remaining on a wafer separated from a semiconductor layer, using HCl and Cl 2 gases under high temperature and low pressure conditions;
polishing the residue-removed wafer physically and chemically; and
cleaning the polished wafer.
2 . The method of claim 1 , wherein the removing of the residues is performed at temperature from about 400° C. to about 2000° C., at a pressure from about 1 to about 10 −9 torr.
3 . The method of claim 1 , wherein the semiconductor layer is a nitride semiconductor layer.
4 . The method of claim 3 , wherein the nitride semiconductor layer comprises any one selected from a group consisting of GaN, AlGaN, InGaN and AlInGaN.
5 . The method of claim 4 , wherein the HCl and Cl 2 gases separate GaN remaining on the wafer into GaCl and N.
6 . The method of claim 1 , wherein the cleaning is performed using a solution containing NH 4 OH.