Semiconductor wafer and vapor phase growth apparatus

A vapor phase growth apparatus comprising a reaction chamber and a plurality of gas inlet ports disposed in a width direction of the reaction chamber, wherein a semiconductor raw material gas is supplied from the plurality of gas inlet ports onto a main surface of a semiconductor single crystal substrate rotating in the reaction chamber in one direction in almost parallel to the main surface thereof to grow a semiconductor thin film on the main surface thereof in vapor phase, characterized by that the vapor growth apparatus further comprises:

• a main dopant gas pipe supplying a dopant gas to all of the plurality of gas inlet ports;
• first auxiliary dopant gas pipe and second auxiliary dopant gas pipe supplying the dopant gas to a specific gas inlet ports selected from the plurality of gas inlet ports;
• a main dopant gas flow rate regulator disposed at the main dopant gas pipe for regulating supply of the dopant gas;
• a first auxiliary dopant gas flow rate regulator disposed at the first auxiliary dopant gas pipe for regulating supply of the dopant gas;
• and
• a second auxiliary dopant gas flow rate regulator disposed at the second auxiliary dopant gas pipe for regulating supply of the dopant gas, and wherein
• the main dopant gas pipe comprises a common gas pipe which is connected with all of the plurality of gas inlet ports,
• the plurality of gas inlet ports are grouped into three kinds of inlet ports including inner inlet ports disposed at the innermost side in a width direction of the reaction chamber, outer inlet ports disposed at the outermost side in the width direction of the reaction chamber and middle inlet ports each between the inner inlet ports and the outer inlet ports, and the first auiliary dopant gas pipe is connected to the inner inlet ports, and the second auxiliary dopant gas pipe is connected to the middle inlet ports, and
• the dopant gas from the first auxiliary dopant gas pipe to the inner inlet ports is regulated by the first auxiliary dopant gas flow rate regulator, and the dopant gas from the second. auxiliary dopant gas pipe to the middle inlet ports is regulated by the second auxiliary dopant gas flow rate regulator.