| 摘要 |
<p>PROBLEM TO BE SOLVED: To prevent foreign matters from entering a wafer by locating holder sections to hold the wafer at a place away from a disc face. SOLUTION: On the periphery of a disc 7 of an ion implanter, many holder sections 8 for holding a wafer are placed. The holder sections 8 are projecting from the face of the disc 7 and each of the holder sections 8 has a clamp ring 9 for holding the wafer. When the ion beam is cast on the wafer from the direction at right angles with the wafer held by the holder sections 8, the ion beam hits a part of the surface of the disc 7 near the outside of the wafer. Therefore, even if foreign matters such as ions of different kinds are sputtered, they do not reach the wafer located at a high position and fall below the holder sections 8. Therefore, the foreign matters never enter the wafer and the characteristics of the products after ion implantation can be kept good. Furthermore, the dust which floats on the surface of the wafer, can be reduced.</p> |
