| 摘要 |
PURPOSE:To improve the electric characteristics of a semiconductor substrate by heat treating silicon single crystal at the prescribed high temperature, sequentially heat treating from the prescribed low temperature to high temperature in multiple stages in dry atmosphere and generating internal defect in high density in the substrate, thereby increasing the gettering effect. CONSTITUTION:A silicon substrate heat treated at high temperature higher that 1,200 deg.C in advance is sequentially heat treated from 500 deg.C, is raised by 50-100 deg.C sequentially, and is eventually raised to 800 deg.C in multiple heat treating stages. Since the internal defects occurred in the substrate at the respective temperature stages have critical size, the defects are produced in high density more than the critical size at every heat treating stages, are absorbed by the gettering effect to suppress the infinitesimal defects, and the electric characteristics of the device can be improvecd. |
