发明授权
US6152806A Concentric platens 失效
同心压板

Concentric platens
摘要:
A chemical mechanical polishing apparatus includes a plurality of concentric rotatable platens for polishing a substrate. A polishing pad is attached to each platen. Each platen may be rotated independently in either clockwise or counter-clockwise direction.
公开/授权文献
信息查询
0/0