| 摘要 |
PURPOSE:To make the precise control of C doping quantity possible by using CO gas as an impurity source to mix H2 gas and reactive gas over a reduction temperature when As ags or N2 gas is used as carrier gas to grow epitaxially a P-type V-III group compound semiconductor layer in a vapour phase. CONSTITUTION:GaAs substrate 5 is provided in reaction tube 1, and Ga source 4 is provided in inside cylinder 4 provided inside reaction tube 1. Next, carrier gas of N2 or Ar which does not include CO is fed into circular space 1b of reaction tube 1 from entrance 1d, and CO gas is flowed from entrance 1e. After that, AsCl3 gas and H2 gas are flowed from entrances 2b and 2e of inside tube 2 respectively, and at this time, the addition quantity of H2 is defined as 0.01 to 30%. Thus, a temperature near upper stream part 1a of reaction tube 1 is set below 400 deg.C, and reduction is not performed there. Then, AsCl3 reactive gas and H2 gas are mixed in crystal growing region 1c where a temperature is set over 600 deg.C, and a crystal layer is generated on substrate 5. |
