20-01-2012, 12:28 PM
VLSI TECHNOLOGY
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Wafer Lapping
• After the sawing processing the wafer edges are ground in a mechanical process to round the sharp edges created through the slicing process.
• The round edges prevent chipping of the wafers in later processes.
• After edge rounding the wafers are then rough polished to remove most of the damage caused by the wafer sawing process.
• This is known as lapping and is a double sided process performed under pressure using a glycerine slurry with alumina (Al2O3) particles suspended in it.
