Increased lifetime of aluminum-free LEDs on Si substrates grown by MOCVD

An InGaP layer on a Si substrate grown by metalorganic chemical vapor deposition exhibits a mirror-like surface morphology, dark spot density of 1/spl times/10/sup 7/ cm/sup -2/ and 77 K photoluminescence peak wavelength of 645.5 nm. In comparison with a conventional Al-contained AlGaAs/GaAs light-emitting diode (LED) on a Si substrate, an Al-free LED on a Si substrate has no significant growth of dark-line defects. As a result, an increased lifetime has been achieved in an Al-free LED on a Si substrate.