| 摘要 |
PURPOSE:To obtain a high carrier concentration by a method wherein the first solid-state layers having a thickness of an electron wavelength or less and the second solid-state layers having a smaller electron affinity and a thickness through which the electrons of the first ones can pass through are alternately laminated. CONSTITUTION:The first semiconductor layers 4 containing impurities 2 and having the thickness of the electron wavelength or less are laminated on a semiconductor substrate 1. On the other hand, the second layers 5 have the electron affinity smaller than the first ones 4 and the thickness through which the electrons in the first ones 4 can pass through. The first and second semiconductor layers 4 and 5 are alternately laminated and thus form a laminated structure. |
