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Isotropic etching of Si substrate
Results of selective isotropic etching of the Si substrate by xenon fluoride (XeF₂) etching apparatus while leaving a circular silica film on top.
Photo courtesy of Keio University
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Results of selective isotropic etching of the Si substrate by xenon fluoride (XeF₂) etching apparatus while leaving a circular silica film on top.
Photo courtesy of Keio University