| 摘要 |
PURPOSE:To contrive to make uniform the growing speed by a method wherein, when a substrate is circularly shaped, the end part of a susceptor, exposed on the upstream side of the gas stream on a substrate, is formed into semicircular structure. CONSTITUTION:A susceptor 4 is formed with thick tabular graphite or carbon excluding one end face. One end face of the susceptor 4 on the upstream of a flow of gas is formed into the shape having the same radius as the substrate with the center point shifted to the upstream side in the amount of (d), or having a concentrical circle part with the radius larger than the substrate radius in the amount of (d) in the same concentric circle as the substrate. As a result, the distance (l) of the exposed susceptor from the end part of the susceptor 4 along the direction (Z-axis direction) of gas stream to the substrate 6 becomes approximately equal on the greater part of the circular section. When raw gas reached the edge part of the substrate in this kind of susceptor structure, the gas stream has the deposition region of graphite surface of the same distance at any position in the direction at right angle (X-axis) with the gas stream and therefore, the concentration of gas on the edge part of the substrate becomes uniform. As a result, the growing speed in vertical direction can be made uniform.
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