真空ピンチャックの吸着特性(第2報) : 裏面うねりの表面平坦度への影響の低減

概要

論文の詳細を見る
Fabrication of ULSI devices requires a 12-in. silicon wafer to have a site flatness better than 0.1μm/□30mm. Vacuum pin chucks have been developed for flattening processed wafers. This paper describes to reduce the influence of the back-surface waviness on wafer flatness resulting from vacuum clamping. It was found that the contact ratio between the back-surface and the pin tops decreases with an increase in pin pitch or waviness, which degrades wafer flatness. Reducing the vacuum pressure improves flatness only slightly, but polishing for a short time produced good results. It is also shown that flatness better than 0.05μm/30mm is obtained by reducing the waviness to better than 0.1μm/30mm in clamping a 775-μm-thick silicon wafer.
公益社団法人精密工学会の論文
1999-07-05