Apparatus and method for holding and planarizing thin workpieces
摘要
An apparatus and method for holding a thin workpiece such as a semiconductor wafer for operations which require the workpiece to have a high degree of planarity such as photolithographic printing includes positioning the workpiece onto a planar holding face comprising the points of a multiplicity of regularly spaced-apart substantially parallel pins with a thin rim encompassing all pins to contain a vacuum in the region adjacent to the workpiece. The small abutting area of each pinpoint abutment reduces the probability of dirt particles collecting on the holding face and provides a high thrust pressure to dislodge dirt particles interposed between the abutment and the workpiece. A small amount of lateral motion is imparted to the workpiece when it first contacts the holding face to brush off any dirt particles on the abutments.
申请公布号
US4213698(A)
申请公布日期
1980.07.22
申请号
US19780965304
申请日期
1978.12.01
申请人
BELL TELEPHONE LABORATORIES INC
发明人
FIRTION, VICTOR A;HERRIOTT, DONALD R;POULSEN, MARTIN E;RONGVED, LEIF;SAUNDERS, THOMAS E