First, excellent products
1: The silicon surface is smooth and clean.
2: TV: 220±20 μm.
3: Geometry:
Side length 125 ± 0.5mm; diagonal 150 ± 0.5mm, 148 ± 0.5mm, 165 ± 0.5mm;
Side length 103 ± 0.5mm, diagonal 135 ± 0.5mm;
Side length 150±0.5mm, 156±0.5mm, diagonal 203±0.5mm, 200±0.5mm.
Concentricity: The difference between the chord lengths of any two arcs is ≤ 1 mm.
Verticality: The angle between any two sides: 90°±0.3.
Second, qualified products
First grade:
1: There is a little stain on the surface, slight line marks.
2:220±20 μm ≤TV≤220±30 μm.
3: Geometry:
Side length 125 ± 0.5mm; diagonal 150 ± 0.5mm, 148 ± 0.5mm, 165 ± 0.5mm;
Side length 103 ± 0.5mm, diagonal 135 ± 0.5mm;
Side length 150±0.5mm, 156±0.5mm, diagonal 203±0.5mm, 200±0.5mm.
Concentricity: The difference between the chord lengths of any two arcs is ≤1.2mm.
Verticality: The angle between any two sides: 90°±0.5.
Secondary product:
1: The surface has a few stains, line marks, dents, and slight collapse.
2: 220±30 μm ≤TV≤220±40 μm.
3: Dent: The sum of the dents on the surface of the silicon wafer is ≤ 30 μm.
4: collapse range: collapse port is not triangular shape, collapse port length ≤ 1mm, depth ≤ 0.5mm
5: Geometry:
Side length 125 ± 0.52mm; diagonal 150 ± 0.52mm, 148 ± 0.52mm, 165 ± 0.52mm;
Side length 103 ± 0.52mm, diagonal 135 ± 0.52mm;
Side length 150±0.52mm, 156±0.52mm, diagonal 203±0.52mm, 200±0.52mm.
Concentricity: The difference between the chord lengths of any two arcs is ≤ 1.5 mm.
Verticality: The angle between any two sides: 90° ± 0.8.
Three best products:
1: There is oil on the surface but the color of silicon wafer is not black, and the line marks and silicon fall off.
2:220±40 μm ≤TV≤220±60 μm.
3: Silicon falling: The entire silicon wafer is detached from the edge of the silicon crystal or part of the silicon crystal falls off.
Third, unqualified products
Severe line marks, thick flakes: TV>220±60 μm.
Flaps: Silicon wafers with defects that can be changed to Φ103.
Air hole piece: There are perforations in the middle of the silicon piece.
Profiles: Cut square round silicon wafers that have not been ground.
Chamfers (concentricity): The difference between the chord lengths of any two arcs is >1.5mm.
Diamond plate (perpendicularity): The angle between any two sides is >90°±0.8.
Indentation: The sum of the dents on both sides of the wafer is >30 μm.
Dirty film: The surface of the wafer is heavily stained and yellowish black.
Deviation of size: The geometric size exceeds the range of secondary products.
Note: The silicon thickness for the above standard is 220μm.
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