| 摘要 |
PURPOSE:To obtain a high-connectration III-V-group-compound epitaxial layer by supplying a specified amount of S at or above 720 deg.C, and changing the carrier from H2+N2 or a mixed system of inactive gas to N2 or an inactive-gas system. CONSTITUTION:A GaAs substrate 12 is kept at or above 720 deg.C, and N2 and H2 are supplied 15, 16 separately or in a mixed state. A specified amount of S 13, which is heated to a specified temperature of 90 deg.C or less, and AsCl3 gas 14 are supplied 18 and 19 by carrier gas. In the case of an N2 system carrier, the growing speed of GaAs decreases in inverse proportion to the temperature, and the impurity concentration which is accepted into GaAs from the reactive system becomes relatively high. In the case of an H2-system carrier, the carrier concentration does not increase remarkably even though the growing temperature is raised. In the N2 system, the non-added carrier level 1 is lower than that of the H2 system at or below 700 deg.C, but is reversed above 700 deg.C. Then, with relationship betweem the carrier concentration and the growing temperature being considered, epitaxial growth is performed within the temperature range above 720 deg.C in which the growing speed of GaAs is low, thereby high concentration can be obtained. |
