HIP焼結法による砒化ガリウムの緻密化

抄録

GaAs was thermally analyzed in air using a TG-DTA apparatus prior to the densification. Result showed that GaAs was oxidized at 550°C. Then, normal sintering at 800°C for 2h was conducted under N₂ atmosphere. The sintered body did not densify with a density of 3.93g/cm³ (relative density 74.0% T. D.). Therefore, green compacts of GaAs were encapsulated in glass containers under reduced pressure and densified by HIP treatment. Resultant densities increased with increasing temperature, pressure, and soaking time. The maximum density of 5.15g/cm³ (97.0% T. D.) was successfully achieved by the HIP treatment at 800°C and 150MPa for 2h. Microstructures of the fracture surfaces observed with a scanning electron microscope (SEM) showed little pores.