| 摘要 |
PURPOSE:To incorporate an impurity in a donor or acceptor easily with a high accuracy and reduce the cost of a single crystal, by passing a gas containing the impurity through a pulling up furnace, and pulling up a semiconductor silicon single crystal by the Czochralski method. CONSTITUTION:An electric current is passed through a heating heater 2 in a pulling up furnace 1, and a crushed silicon 5 is melted in a quartz crucible 4 placed in a graphite crucible 3. On the other hand, a gas containing an impurity is fed from a feed port 6, and passed through a flowmeter 7 and a timer 8, and the quantity of the gas passed therethrough is accurately measured and regulated. A base gas is passed from a feed port 9 through a flowmeter 10 in a constant flow rate to dilute the gas containing the impurity and pass the gas through the pulling up furnace 1. A vapor of a phosphorus compound, e.g. PH3 or POCl3, is used as the gas containing the impurity to be used in pulling up the N type single crystal, and a vapor of a boron compound, e.g. B2H6, BCl3 or BBr3, is used as the gas containing the impurity to be used in pulling up the P type single crystal. |
