Method of epitaxially growing a substrate for highly bright led

Abstract

Abstract A substrate for a highly bright LED and a method of epitaxially growing the same employ an AuZn alloy as an oh­mic electrode for a p-type Al x Ga 1-x As layer (2), and are based upon the fact that the contact resistance decreases with an increase in the carrier concentration in the above layer and accordingly the voltage (V F ) required for a forward current of 20 mA decreases. When a vapor phase growth method and a liquid phase growth method are used in combination, an ep­itaxial layer grown by the vapor phase growth method (MOCVD method, MBE method etc.) has a carrier concentration which is 3 to 5 times as great as that of the epitaxial layer formed by the liquid phase growth method (LPE method) and the reproducibility is good. The p-type Al x Ga 1-x As layer (2) is used as a contact layer for the electrode to decrease the con tact resistance while suppressing variance. ABSTRACT A substrate for a high-intensity LED and the method of epitaxially growing the substrate according to the invention are based on the fact that, in using an AuZn alloy or the like as the ohmic electrode of the p-type Al x Ga 1-x As layer (2), the higher the carrier concentration of this layer, the smaller the contact resistance and the lower the applied voltage (V F ) necessary for passing a forward current of 10 mA. Joint use is made of gas-phase epitaxy and liquid-phase epitaxy. A layer having a carrier concentration three to five times that of an epitaxial layer formed by liquid-phase epitaxy (LPE) can be realized with excellent reproducibility by gas-phase epitaxy (MOCVD process, MBE process, etc.). By utilizing this p-type Al x Ga 1-x As layer (2) as an electrode contact layer, contact resistance can be reduced and variance diminished.

Inventors

• 👤 Masahiro Mitsubishi Monsanto Chem.Comp. Noguchi

Bibliographic Details