| 摘要 |
PURPOSE:To improve the degrees of integration of semiconductor elements by a method wherein O ions and As ions are twice injected to a semiconductor region on the surface of a GaAs substrate and stable high resistance layers are obtained. CONSTITUTION:An N-epitaxial layer 5 on a semi-insulating GaAs substrate 4 is coated with a mask 6, and O ions are irradiated, and let reach to the substrate 4. O ions are distrubuted into GaAs, function as traps, prevent the movement of carriers, and form high resistance layers 7 at the both sides of an active layer 8. However, As on the surface of the N-layer 5 disperses outside the substrare during heat treatment after injecting O ions, O2 enters portions where As escapes and serves as donars, and a conductive layer is easy to be formed on the surface of an insulating layer after heat treatment. As ions are further injected, and the quantity of injection is optimized in response to heat treatment time. When injection is excessive, Ga cavities are formed, and electric characteristics are remarkably deteriorated. The normal quantity of injection may be 10<13>-15<15>cm<-2>. After ions are injected twice, the whole is annealed in H2 or Ar. This constitution can accurately decide a region of the active layer, can contract the separating distance of elements, and improves yield and the degree of integration. |
