| 摘要 |
PURPOSE:To attain satisfactory effects simply with high productivity by a method wherein gettering is conducted in such a state that impairment is inflicted on part of the main surface of a semiconductor by injecting Kr ions. CONSTITUTION:Kr<+> are injected into part of the main surface of an Si wafer at an acceleration voltage of 35-300kV with a dosing quantity equal to 10<13>-10<6>/cm<2> while a suitable peak range is selected. Then, it is heat-oxidized, annealed and so processed that an Al electrode is formed. As a result, the crystallization of the wafer and the carrier life are improved and lengthened. Since Kr<+> according to this method is inert, the furnace is unpolluted, making unnecessary the coating of the back. The gettering region with the desired impairing density in the wafer can be readily formed, while the sufficient impairing region can be formed with a small dosing quantity since Kr has large mass. |
