| 摘要 |
PURPOSE:To increase the light emission efficiency, by reducing the donor concentration of n type GaP on the n type GaP substrate toward growing direction, and by taking high concentration at the pn junction for the concentration of the center of illumination (N). CONSTITUTION:When Ga is molten with temperature risen under H2 atomosphere in the quartz made reaction furnace, the surface of the furnace is reduced with H, Si is mixed with high concentration in Ga molten liquid, and the epitaxial layer added by high concentration Si on the n type GaP substrate is grown until the atomosphere is selected to Ar. Since SO2 absorbed on the boat is exhausted with reduction by H2, the donor is mainly Si. The growing at the latter half is made under Ar atomosphere including NH3, a lot of N2 is filled to Ga molten liquid, Si is decreased by making stable compound with the Si partly molten, and the donor concentration is decreased by S starting to solve from the n type GaP substrate. The N concentration of impurity at the center of light emission is increased since N is easily entered because of low donor concentration, and it is not flown from the Ga molten liquid because of Ar atomosphere. Thus, the light emission efficiency can be increased. |
