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Workmanship rejection criteria:
Any ink dot cracking/peeling on peripheral or interior die which may inhibit use of ink dot recognition system at Pick and Plate or Die Attach operations.
Peeling or "halo" ink dots such as those on the right might not be detected by ink dot recognition systems.
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Any lifting metal left in the scribe street which is large enough to bridge the narrowest spacing between unglassivated operating material (see foreign material criteria for clarification).
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Any material in which the ink dots are not nominally centered on reject die.
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Any wafer backside which exhibits the following: lifting/peeling of backside metal, non-uniform backside finish, or contamination/foreign material which cannot be completely removed by gentle cleaning using a clean room wipe dampened with Isopropyl.
Fusible links and laser trim areas on the die are often mistaken as rejects by those unfamiliar with them. When present they should be accepted as "by design". This includes instances where the pattern of open and closed links varies from die to die within a wafer unless the die datasheet specifically designates as open or closed as part of product definition.
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Photograph above shows laser trim area opened by design on left trim pad and left closed on right.
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This photograph shows fusible link area left open at left and closed on right by design.
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