In Process Characterization of Gallium Arsenide Crystals by X-Ray Digital Radiography and Computed Tomography
Gallium arsenide has promised to revolutionize the semiconductor industry for many years. However, numerous practical difficulties have prevented this potential from becoming reality. As part of a DARPA funded effort to enhance the manufacturability of gallium arsenide crystals, we have designed and implemented an x-ray inspection system for imaging these crystals during growth. The objective of the work is to measure melt height, crystal diameter, meniscus shape, and liquid-solid interface shape of a 3 in. diameter crystal grown using the liquid encapsulated Czochralski process. The shape of these structures is a critical factor in determining whether the growth process results in a single crystal with good electrical properties, or whether twinning or polycrystalline growth is present.
KeywordsCompute Tomography Image Gallium Arsenide Liquid Region Coordinate Measuring Machine Digital Radiography
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