QUARTZ MEMBER FOR SEMICONDUCTOR MANUFACTURING EQUIPMENT AND METHOD FOR METAL ANALYSIS IN QUARTZ MEMBER

摘要

Quartz member such as a quartz tube for semiconductor manufacturing equipment capable of heat treating a substrate to be treated without causing contamination, a manufacturing method of such quartz member, thermal treatment equipment furnished with such quartz member, and an analysis method of metal in quartz member are provided. A quartz specimen is immersed in hydrofluoric acid to expose a layer to be analyzed located at a prescribed depth. On an exposed surface, a decomposition liquid such as hydrofluoric acid or nitric acid is dripped to decompose only an extremely thin layer to be analyzed, followed by recovering of the decomposition liquid. The decomposition liquid is quantitatively analyzed by use of atomic absorption spectroscopy (AAS) or the like to measure an amount of metal contained in the decomposition liquid. From a difference of thicknesses before and after the decomposition and an area of dripped decomposition liquid, a volume of a decomposed layer to be analyzed is obtained. From this and the amount of metal contained in the decomposition liquid, a concentration of metal contained in the layer to be analyzed, in addition a diffusion coefficient of a layer to be analyzed is calculated. With thus obtained diffusion coefficient as an index, quartz material in which metal diffuses with difficulty is sorted out. With thus sorted quartz material, a quartz member used for semiconductor manufacturing equipment such as a quartz tube is manufactured.