QUARTZ GLASS JIG FOR HEAT TREATMENT OF SILICON WAFER AND ITS USE METHOD

摘要

PURPOSE: To form a quartz glass jig which is heat-treatable without contaminating silicon wafers by forming a wafer supporting member of a quartz glass jig for heat treatment of silicon wafers by high-purity quartz glass regulated in the content of specific elements. CONSTITUTION: This quartz glass jig 1 is formed by integrally welding a wafer placing circular member 2 and the supporting member 3 and heat-treats the silicon wafers 5 at a high temp of about 1000 deg.C after placing the silicon wafers in grooves 4 for placing the wafer. The supporting member 3 is formed of the quartz glass having 5 to 20ppm aluminum element content, 0.1 to 1ppm lithium element content and <=0.1ppm sodium element content and having preferably 120 to 230ppm OH group concn. The supporting member 3 is so formed that the weight thereof attains >=30% of the total weight of the quartz glass jig 1. The wafer placing member is formed of the quartz glass having <=3ppm aluminum element content and <=0.05ppm lithium element content. The life of the jig is decided by the concn. of the sodium element contained therein by providing the supporting member 3 with projections for analysis.