| 摘要 |
PURPOSE:To heighten the efficiency and extend the life by setting the difference in the lattice constant between a chemical semiconductor crystal and an epitaxial layer made of a chemical semiconductor belonging to the same group on the periodic table formed thereon below a specified order. CONSTITUTION:For example, a crystalization apparatus is composed of a core pipe 7, a uartz ample 8, ports 9 and 19 and a temperature adjusting section 10. Here, a single crystal of GaAs is used for a chemical semiconductor substrate 18. In and GaP belonging to the same group on the periodic table are set on a melt 16 to adjust the temperature for each section whereby an epitaxial layer is formed on the substrate 18. The difference in the lattice constant between the GaAs substrate and the In0.5 Ga0.5P growth layer depends on the steam pressure of the P. With optimum control of pressure of P, it is reduced below 1 X 10<-5> deg.A and hence, a hetero junction with a extremely small difference of the lattice constant is made possible. Besides, the same results can be obtained in hetero junction devices made of various chemical semiconductors. |
