Semiconductor wafer alignment apparatus

An apparatus for dicing a wafer of semiconductor material opaque to visible light, having first and second major surfaces and first and second reference marks on said first surface thereof comprising,

• a wafer being transparent to visible light and having first and second surfaces and first and second reference marks on said first surface corresponding to said first and second reference mark on said semiconductor wafer,
• means for establishing said marks on said transparent wafer in a known fixed position,
• dicing means disposed adjacent said second surface,
• means for directing a beam of visible light along a given axis at the second surface of said transparent wafer to indicate the position of said dicing means with respect to said reference marks,
• means for aligning said dicing means with respect to said first and second marks and said transparent wafer by positioning said dicing means with respect to said first and second marks on said first surface in said known fixed position,
• means for replacing said transparent wafer with said semiconductor wafer so that said first and second marks on said first surface of said semiconductor wafer are disposed in corresponding position with said first and second marks on said transparent wafer in said known fixed position, and
• means for traversing said dicing means along said semiconductor wafer surface in a known direction relative to said first and second marks on said semiconductor wafer.

An apparatus for dicing a semiconductor wafer, opaque to visible light, having first and second major surfaces and first and second reference marks on said first surface thereof comprising,

• optical means for viewing said marks with visible light reflecting from said first surface,
• means for aligning said marks with a reference position,
• dicing means contacting said second surface,
• means for establishing said dicing means in a known relationship with respect to said optical means and said reference position, and
• means for traversing said dicing means across said second surface of said wafer to dice said wafer into individual units.

An apparatus for dicing a wafer of semiconductor material, said wafer having a plurality of integrated circuits, separated by kerf areas, and a pair of reference marks formed on the front surface thereof comprising,

• an alignment station,
• a transfer station, and
• a dicing station,
• said alignment station including viewing means for viewing the front surface of a wafer on first and second optical axes and
• alignment means for aligning the reference marks on the front surface of said wafer to a fixed base line established relative to said optical axes,
• said transfer station including inverting means for inverting the aligned wafer to expose the back surface of the wafer while maintaining the wafer aligned with reference to said base line and
• transfer means for transferring said inverted, aligned wafer along a constrained path to said dicing station,
• said dicing station including,
• means for maintaining said inverted wafer in said aligned relationship,
• means for guiding said aligned, inverted wafer to a set position adjacent to and a fixed distance from said alignment station and
• means for dicing said wafer,
• said dicing means having a predetermined relationship with respect to said base line so that said inverted, aligned wafer is aligned for dicing on its back surface in said kerf areas, with respect to said base line.