| 摘要 |
PROBLEM TO BE SOLVED: To provide a hydrogen ion implantation method to a semiconductor base board for limiting generating ion species of hydrogen to one kind by extracting a hydrogen anion beam from plasma by an extraction electrode system composed of plural porous electrode plates, and implanting a hydrogen anion in the semiconductor base board up to the prescribed depth. SOLUTION: An accelerating electrode 36, a decelerating electrode 37 and an earth electrode 38 composed of three porous plates are arranged as an extraction electrode system. When a second switch 44 and a third switch 45 are closed, an anion beam is extracted from main discharge plasma 57 by the action of a Vacc 42. When a first switch 40 is closed, an electron and an anion are pulled in a main discharge chamber 30 from an MP cathode 28 to generate an anion abundant main discharge plasma 57. The whole switches 40, 44, 45 are closed, an anion is continuously extracted, and a hydrogen anion is implanted in an Si wafer 58 on a susceptor 47. Only anion and electron are implanted in the Si wafer 58 due to a positive bias of the decelerating electrode 37. |
