Marking semiconductor wafers by converting identification numbers into binary coded pattern which is projected bit by bit onto resist layer, followed by etching

摘要

A resist (4) is applied to the surface of the semiconductor wafer (2), which includes a substrate (1). The projector (3) shades (6) limit the field of illumination during photolithographic projection. The wafer is laid on a moveable substrate holder in the projection apparatus. From a prepared identification label, a binary number is formed and converted to a representative, planar, binary-coded pattern (5). For each bit of the binary number, the holder is moved and the cited photolithographic projection takes place. The resist layer is then etched to form structural elements (10) of the binary coded pattern.