SEMICONDUCTOR WAFER AND ITS MANUFACTURING METHOD

摘要

It is an object of the invention to provide a semiconductor wafer obtained by forming a semiconductor thin film with uniform resistivity on a main surface of a semiconductor single crystal substrate of 300 mm or more in diameter. When a process gas is supplied to over a main surface of a silicon single crystal substrate 12 in rotation in almost parallel to the main surface thereof in one direction in a reaction chamber 10 through six inlet ports 18a to 18f disposed in width direction of the reaction chamber 10, H2 gas, a semiconductor raw material gas and a dopant gas are supplied onto an area in the vicinity of the center of the main surface of the silicon single crystal substrate 12 and an intermediate area thereof through the inner inlet ports 18a and 18b and the middle inlet ports 18c and 18d, and only H2 gas and the semiconductor raw material gas without the dopant gas are supplied onto an area in the vicinity of the outer periphery thereof from the outer inlet ports 18e and 18f. In such arrangement, a dopant gas produced by the auto-doping phenomenon is supplied onto the area in the vicinity of the outer periphery of the main surface of the silicon single crystal substrate 12. For this reason, the dopant gases from both sources are combined, thereby a concentration of the dopant gas supplied over all the main surface of the silicon single crystal substrate12 is almost uniform.