3-9. Comet Tails
Comet tails have a discrete head and trailing tail. These features are aligned parallel to the major at. Usually, all comet tails tend to be of the same length. Count once per occurrence. Two comet tails within 200 microns count as one.
5-4-4-1 SiC Epitaxial Growth Processes An interesting variety of SiC epitaxial growth methodologies, ranging from liquid-phase epitaxy, molecular beam epitaxy, and chemical vapor deposition(CVD) have been investigated . The CVD growth technique is generally accepted as the most promising method for attaining epilayer reproducibility, quality, [...]
2-13.Hex Plate Hexagonal shaped platelets on the surface of the wafer which appear silver in color to the unaided eye, under diffuse illumination.
1-5.Thermal Expansion Coefficient Thermal expansion is the tendency of matter to change in volume in response to a change in temperature. When a substance is heated, its particles begin moving more and thus usually maintain a greater average separation. Materials which contract with increasing temperature are [...]
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 [...]
2-7.Primary Flat Orientation The at of the longest length on the wafer, oriented such that the chord is parallel with a specied low index crystal plane. Measured on one wafer per ingot using Laue back-reection technique with manual angle measurement.
2-26.TTV Total Thickness Variation (TTV): The maximum variation in the wafer thickness. Total Thickness Variation is generally determined by measuring the wafer in 5 locations of a cross pattern (not too close to the wafer edge) and calculating the maximum measured difference in thickness.
