| 摘要 |
PURPOSE:To obtain the vapor-grown epitaxial film in a short time and with the uniform quality irrespective of the shape and size of the GaAs substrate by giving some contrivance to the support board of the substrate. CONSTITUTION:Screen 17 of the same material as substrate support board 16 is provided closer to the low temperature side than the self-standing groove of GaAs substrate 18. Height h' and width w' of screen 17 are set identical to or larger than height h and width w of the substrate. Using such device, the epitaxial growing is carried out. Conventionally, the epitaxial growing speed is said to be decided by the mol ratio of AsCl3 and the substrate temperature, and now it is found that the growing speed increases in proportion to the width and height of the substrate crystal. In this connection, the size and shape of the substrate must be kept constant to secure a constant speed for the epitaxial growth. With this device, the resistance to the flow of the reaction gas is decided by the screen but by the substrate crystal. Therefore, the growing speed is always decided by the area of the screen to a constant rate. |
