Recovery of LED Emission Power under the Exposure to γ-n-Pulse

Abstract

The article presents results of the study of the effect of LED power modes based on AlGaAs heterostructures (short-circuit, open circuit, and active mode with the passage of operating current during irradiation) on the resistance to γ-n-pulse exposure. Reduction of LED emission power under the influence of γ-n-pulse occurs in two stages irrespective of irradiation power mode, with each stage characterized by its own regularity and its own factor. Built-in electric field of p-n-junction does not contribute significantly to the degradation of LED power when exposed to γ-n-pulse. At irradiation of LED in active power mode after exposure to γ-n-pulse (Fn ≤ 1.5·1012n/cm2, Dγ ≤ 20 Gy (Si)) a recovery of LED power by the value of ΔP is observed. Recovery of ΔP power leads to reduction of the damage factor at the first stage, to increase of the LED resistance, and to shift of the boundary between the stages to the area of higher neutron fluences. It is supposed, that the observed jump-like increase of ΔP radiation power under the influence of γ-n-pulse is caused by radiation-stimulated annealing of local mechanical stresses that is generated under the condition of passing of operating current through LED.