Selective MOVPE growth of GaAs on Si and its applications to LEDs

Abstract

The two main problems still encountered during the growth of GaAs on Si are the lattice mismatch and the difference in thermal expansion coefficient. In this paper we will concentrate on the use of selective MOVPE growth of GaAs on Si and its applications to LED fabrication. The two reported techniques - small area selective growth and spatial control of microcrack formation through selective growth - resulted in higher yield and higher output power of IR-DH LEDs. By the implementations of thermal cycling procedures and the growth of an InGaAs/GaAs strained layer superlattice in the LED buffer layer we succeeded in increasing the output power over a factor of 5. For 3 μm GaAs on Si layers, we obtained X-ray FWHM values of 125 arc sec and etch pit density values of (1.0 ± 0.5)×106 cm-2.