2.Definition of Dimensional Properties,Terminology and Methods of Silicon Carbide Wafer

2-1.Wafer Diameter

2-1.Wafer Diameter The linear distance across the surface of a circular slice which contains the slice center and excludes any flats or other peripheral fiduciary areas. Standard silicon wafer diameters are: 25.4mm (1″), 50.4mm (2″), 76.2mm (3″), 100mm (4″), 125mm(5″), 150mm (6″), 200mm (8″), and 300mm (12″). The linear dimension across [...]

2-2.Wafer Thickness, Center Point

2-2.Wafer Thickness, Center Point Thin (thickness depends on wafer diameter, but is typically less than 1mm),circular slice of single-crystal semiconductor material cut from the ingot of single crystal semiconductor; used in manufacturing of semiconductor devices and integrated circuits; wafer diameters may range from 5mm to 300mm. Measured with ANSI certied non-contact [...]

2-3.Wafer Flat Length

2-3.Wafer Flat Length Linear dimension of the at measured with ANSI certied digital calipers on a sample of one wafer per ingot.

2-4.Wafer Surface Orientation

2-4.Wafer Surface Orientation Denotes the orientation of the surface of a wafer with respect to a crystallographic plane within the lattice structure. In wafers cut intentionally “off orientation”, the direction of cut is parallel to the primary  at, away from the secondary  at. Measured with x-ray goniometer on a sample [...]

2-5.Misorientation

2-5.Misorientation In wafers cut intentionally “off orientation”, the angle between the projection of the normal vector to the wafers surface onto a {0001} plane and the projection on that plane of the nearest <11-20> direction.  

2-6.Wafer Primary Flat

2-6.Wafer Primary Flat The flat of longest length on the wafer, oriented such that the chord is parallel with a specified low index crystal plane; major flat. The primary at is the {10-10} plane with the at face parallel to the <11-20> direction.  

2-7.Primary Flat Orientation

2-7.Primary Flat Orientation The at of the longest length on the wafer, oriented such that the chord is parallel with a specied low index crystal plane. Measured on one wafer per ingot using Laue back-reection technique with manual angle measurement.  

2-8.Secondary Flat Orientation

2-8.Secondary Flat Orientation A at of shorter length than the primary orientation at,whose position with respect to the primary  orientation at identies the face of the wafer.  

2-9.(Area) Wafer Contamination

2-9.(Area) Wafer Contamination Any foreign matter on the surface in localized areas which is revealed under high intensity (or diffuse) illumination as discolored, mottled, or cloudy appearance resulting from smudges, stains or water spots.  

2-10.Cracks

2-10.Cracks A fracture or cleavage of the wafer that extends from the frontside surface of the wafer to the back-side surface of the wafer. Cracks must exceed 0.010” in length under high intensity illumination in order to discriminate fracture lines from allowable crystalline striations. Fracture lines typically exhibit sharp, thin [...]