Efficient electroluminescence from GaAs diodes at 300 ° K

Light emitting GaAs diodes will be described which differ from standard ones insofar as the p-n junction is completely solution regrown and amphoterically doped. The amphoteric dopant Si is the dominant impurity on both sides of the junction giving rise to a highly compensated p region. The light emitting region is extremely wide up to 50 microns. The energy of the emitted light is less than the band gap of GaAs at 300°K. The most important feature of these diodes is that their external quantum efficiencies are much higher than those of the standard type diodes having comparable optical geometries. Values as high as 6% have been measured at 300°K when an anti-reflecting coat was applied to the 4 cleaved sides of a diode shaped to the form of a parallelepiped. Without the coating, the external quantum efficiency was 3.7% for this particular diode. Values, close to 3% for uncoated end faces are quite commonly found. Comparable values for standard Zn doped diodes of similar structures are approximately 1%.