| 摘要 |
<P>PROBLEM TO BE SOLVED: To dope with high precision impurities such as carbon when a silicon/ germanium mixed crystal film is grown to effectively suppress diffusion of impurities such as boron. <P>SOLUTION: When a silicon material gas, a germanium material gas, a boron material gas, and a carbon material gas are introduced into a reaction chamber 1 to grow a silicon/germanium mixed crystal film on a substrate 2, under a condition that carbon is added to the silicon/germanium mixed crystal film at about 0.5%, a flow rate of the carbon material gas is set to 5 sccm or more, and further a supply concentration of the carbon material gas is lowered down to about 1.0%. Thus, carbon of a concentration required for suppressing a diffusion of boron is added to a film, and further a concentration of carbon is equal to or higher than a concentration of boron in any depth area, so that an offset is not caused in entrapping of carbon and boron into the silicon/germanium mixed crystal film. <P>COPYRIGHT: (C)2003,JPO |
