| 摘要 |
PURPOSE:To enable the heating treatment with highly pure hydrogen while preventing deterioration in degree of vacuum within a growth chamber due to introduction of the hydrogen, by providing a hydrogen supply pipe which can directly apply the hydrogen only to a molecular beam source and further providing a shielding plate at the inlet port thereof. CONSTITUTION:A hydrogen valve 3 is opened to a molecular beam source 1 whose temperature has been previously increased, so that hydrogen is introduced via a bellows 14 into the source 1 through a hydrogen supply pipe 10. The hydrogen is applied to the molecular beam source 1, as indicated by the arrows, after it once impinges on the bottom face 11a of a shielding plate 11. All molecules of the beams from the source 1 are adhered on the bottom face 11a of the shielding plate 11 but not on a hydrogen inlet port 12. Thus the cleaning operation of the molecular beam source 1 is not adversely effected in any way. The hydrogen is introduced to such an extent that the degree of vacuum within a growth chamber 2 becomes in the order of 10<-3>torr. This means that the molecular beam source 1 can be cleaned with one-thousandth of hydrogen in comparison with prior arts. |
