| 摘要 |
PURPOSE:To obtain uniform film on a great number of substrate in a single time, by mounting a plural number of gas feed hole to a reactive tube and introducing feed tubes having a plural number of holes to both sides of the reactive tube. CONSTITUTION:Inside a reactive tube 1 a gas feed tube 4' having small holes 8 with fixed intervals is fixed. The SiO2 is formed on the Si substrate 8 placed on a boat 7 by the usual vacuum CVD method. In this construction, the scattering of the film thickness on the whole surface of the substrate 8 becomes below + or -3%, a remarkable decrease in comparision with the existing method. At the same time the film properties with less scattering in both the density and the refractive index can be obtained. |
