METHOD FOR GROWING CRYSTAL OF GA1-XALXAS

摘要

PURPOSE:To obtain a light emitting diode having high brightness and efficiency with excellent reproducibility, by selecting the total period of a growth time for an n-layer after growing a p-layer and the time for holding the layer at a high temperature in the same growth atmosphere after growing the n-layer so as to satisfy a specific relationship in liquid epitaxial growth by a temperature gradient method. CONSTITUTION:A temperature difference is provided between a p-melt containing Zn as a p-type impurity and Al and GaAs as growth materials melted therein and an n-melt containing a metal to be an n-type impurity and Al and GaAs as growth materials melted therein to bring as substrate crystal into contact with the low temperature side of the melts. The substrate crystal is then held for a prescribed time to grow a p-Ga1-xAlxAs layer and n- Ga1-xAlxAs layer on the substrate. In the process, the following relationships is satisfied. That is the total period [t (min)] of the growth time for the n-layer after growing the afore-mentioned p-layer and the time for holding the layer at a high temperature in the same growth atmosphere after growing the n-layer is determined from the weight ratio of the Al to the GaAs [Al]/[GaAs]=y and t=alpha.exp(-beta.y)+ or -33% (alpha=193, beta=3.6).