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.
5-1 Introduction Silicon carbide (SiC)-based semiconductor electronic devices and circuits are presently being developed for use in high-temperature, high-power, and high-radiation conditions under which conventional semiconductors cannot adequately perform. Silicon carbide’s ability to function under such extreme conditions is expected to enable significant improvements to a far-ranging variety [...]
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, [...]
2-11.Edge Chips Any edge anomalies (including wafer saw exit marks) in excess of 1.0 mm in either radial depth or width. As viewed under diffuse illumination, edge chips are determined as unintentionally missing material from the edge of the wafer.
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 [...]
3-7. ID Correct and Major Wafer Flat Both should be readily discernible.
5-4-1 Historical Lack of SiC Wafers Reproducible wafers of reasonable consistency, size, quality, and availability are a prerequisite for commercial mass production of semiconductor electronics. Many semiconductor materials can be melted and reproducibly recrystallized into large single crystals with the aid of a seed crystal, such as [...]
