Heat treatment effect upon etch-channel formation in synthetic quartz crystals

A simple and low-cost technique has been developed to reduce the etch-channel density in synthetic quartz crystals. Synthetic quartz specimens were heat-treated under a variety of conditions. The etch-channel density in synthetic quartz crystals was decreased by the heat treatment. The specimens were also evaluated by the infrared absorption method and impurity analysis. The reduction ratio of etch-channel density was low in specimens with higher infrared absorption coefficient and higher impurity content. An atomic diffusion phenomenon is inferred as a possible mechanism to account for the effect of heat treatment on the reduction of etch-channel density.