GaP Red Light Emitting Diodes Produced by a Rotating Boat System of Liquid Phase Epitaxial Growth

Abstract

An improved rotating boat system for liquid phase epitaxial growth has been developed. With this system red light emitting diodes can be mass produced. Its features are that substrates can be fixed by the remarkably simple method of attaching a small volume of melted gallium to the substrate holding plate and pressing the substrate closely against it. It is also suitable for mass production in that the construction of the boat for liquid phase epitaxial growth simplifies the operation for crystal growth; large quantities of substrates of large diameter (30–50 mm) can be treated in one processing batch; the consumption of the Ga melt is small. The growing surface is mirrorlike. A double step process, in which n‐ and p‐type layers are grown in two separate steps is used in the diode fabrication. Another feature is that the same Ga melt is used ten times for the growth of n‐ and p‐type layers, respectively. Encapsulated mesa diodes with efficiencies of 6% are routinely obtained from the sequential use up to ten times of the Ga melt and also, the average electroluminescence time decay is 500 nsec. The maximum efficiency is 10% .