| 摘要 |
PROBLEM TO BE SOLVED: To provide a method capable of producing a single crystal having a desired resistivity without decreasing process capability. SOLUTION: An evaporation rate formula for calculating a dopant evaporation rate is drawn by considering the influence of segregation in producing a single crystal 6 by utilizing a single crystal raising apparatus 1, the evaporation area of a volatile dopant, and the influence of raising speed. In a predetermined timing at the time of raising, the gas flow quantity and furnace internal pressure of a chamber 30 are controlled so that the dopant evaporation cumulative amount calculated by an evaporation rate formula is a specified amount. Thus, the difference between the anticipated resistivity profile of a single crystal 6 based on the evaporation rate formula and the actual resistivity profile can be reduced. Since the volatile dopant is not added afterward, the increase in operator's burden, the protraction of production time, the increase of amorphous attaching to the inside of a chamber 30, the impediment of single crystallization, and the increase in burden at the time of cleaning in chamber 30 can be controlled. COPYRIGHT: (C)2009,JPO&INPIT |
