Investigation of AlGaInP heterostructures under gamma‐irradiation in the field of restructuring defect structure

Abstract

AbstractThe given paper presents the results of studying the resistance of AlGaInP heterostructures with multiple quantum wells to 60Co gamma‐quantum irradiation. The research was completed for light emitting diodes (λ = 630 nm). The irradiation was completed under the passive powering mode without the imposition of the electric field while the level of exposure was characterized by the absorbed dose. It has been established that the emission power reduction has three stages. At the first stage the radiation power reduces due to radiation‐induced transformation of the initial structure defects, at the second stage – due to the introduction of radiation defects, in the extreme case the second stage transforms into the third stage (low electron injection mode). On the boundary between the first and the second stages transient processes are observed – restoration of emission power against its general reduction. The authors identify the heterostructures for which a pronounced effect of small doses is observed – restoration of emission power due to radiation‐induced relaxation of mechanical stresses without formation additional structural defects. The given process precedes the first stage of emission power reduction under gamma quantum irradiation. Besides, the authors identify the heterostructures which demonstrate two additional transient processes at the first stage. The researchers also establish the relations allowing describing the emission power change at the given stages. (© 2015 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)