ALUMINUM ALLOY PLATE AND PROCESS FOR PRODUCING THE SAME

摘要

An aluminum alloy plate is provided which is suitable for use as members for apparatuses relating to semiconductors. The alloy plate is satisfactory in plate thickness precision and flatness and can be inhibited from having surface defects. Also provided is a process for producing the plate. An aluminum alloy comprising given components is melted (melting step), and hydrogen gas and inclusions are removed therefrom (dehydrogenation step and filtration step). This melt is cast into an ingot (casting step). According to need, the ingot is homogenized by a heat treatment (soaking step). This ingot is hot-rolled to a given thickness (hot-rolling step), cut (cutting step), and finished by smoothening the surfaces (smoothening step). According to need, the plate may be subjected to straightening (straightening step) and a heat treatment, e.g., annealing (annealing step). The aluminum alloy plate obtained has a surface flatness of 0.2 mm or less per m of rolling-direction length and has fluctuations in plate thickness within ±0.5% of a desired plate thickness.