| abstract |
The alumina sintered body of the present invention has a c-plane orientation degree of 90 determined by the Lotgering method using an X-ray diffraction profile in the range of 2θ = 20 ° to 70 ° when the plate surface is irradiated with X-rays. The number of pores is zero when the cross section cut in the direction perpendicular to the plate surface is polished with an Ar + ion beam and a shielding plate and then examined with a scanning electron microscope at a magnification of 5000 times. , The total mass ratio of impurity elements other than Mg and C is 100 ppm or less. Since this alumina sintered body has high orientation, high density, and high purity, it has higher translucency than conventional. |