The causes of emitting-power instability in GaP:N LED

Abstract A complex study of injection-enhanced processes in GaP:N light emitting diodes under forward bias ( I = 5–30 mA) during the first 2–5 min has been carried out. The electrical, electroluminescent methods, DLTS technique and the method of secondary emission mass spectroscopy have been used. It has been shown that the instability of luminous power of GaP:N LEDs is associated with recombination-enhanced annealing defects in the active region of devices, rather than processes at the contacts. It has been found, that stable LEDs have a significantly higher concentration of O, C and their compounds. A reliable physical model of the processes involved is proposed.