Method and apparatus for aligning the position of die on a wafer table

摘要

A method for determining the position of a die on a wafer table after a wafer (20) has been cut includes stepping the wafer table (22) a series of one die lengths diagonally and after each step compare the die pattern to a reference die to determine street widths between dies. The widths are then averaged. This averaged street width is added to the die length to at the computer (26) to determine the jump distance between good dies. The distance from the reference die is continuously updated and this is used with the average street width to compute the next die position to jump. If the jump to the next die is unsuccessful, jump back to mid-point and if that is unsuccessful, reiterate mid-point jumps until successful.