公开(公告)号：DE1943822A1

公开(公告)日：1970-03-05

申请号：DE1943822

申请日：1969-08-28

Applicant: IBM

Inventor： MORGAN MARK ,  RALPH ROTTMAN HANS

IPC: H01L21/66 ,  G06K7/10 ,  G06V30/224 ,  H01L21/02 ,  H01L23/544 ,  G01N21/30

Abstract: 1,262,393. Semi-conductor devices. INTERNATIONAL BUSINESS MACHINES CORP. 22 Aug., 1969 [30 Aug., 1968], No. 41980/69. Heading H1K. [Also in Division G4] Identifying code marks are etched on pieces of semi-conductor material during an early manufacturing stage of a device to be constructed on the material. The code marks may comprise concentric rings which are scanned by a row of photodetectors transverse to the direction of movement of the material, an annular code track which is scanned by a rotating mask and a single detector, or a series of marks having selected spacing to produce different frequency outputs from a detector, the marks being etched in the kerf area between individual wafer areas. In the latter case a clock is gated on by a first detected frequency f3 and each occurrence of a detected code frequency f1 or f2 in coincidence with a clock pulse shifts the corresponding code bit into a shift register. A further frequency f4 at one end of the code indicates the direction of feed and controls the order in which the shift register contents are gated out.