Radiation Hardness Evaluation of LEDs Based on InGaN, GaN and AlInGaP Heterostructures

Effects of Co-60 gamma radiation on the characteristics of red, green, and blue LEDs

“…It was observed that the LED casing was darkened after the maximum dose of 172.8 kGy. This is also reported by some authors (1). The degradation in the optical output is the result of combination of all above factors; however, it seems that the degradation of the casing is a dominant factor, as, while the Intensity-Power characteristics showed a significant degradation, the I-V characteristics were almost intact.…”

“…LEDs have now almost replaced gas discharge emitters or light bulbs, and they are frequently used in various applications involving light emission and displays (1). LEDs offer some notable advantages such as simple fabrication, low cost, good linearity, and thermal stability (2,3).…”

“…This necessitates investigations on the durability, reliability of LEDs under low, medium, and harsh radiation environments (4)(5)(6). The radiation induced modifications in the performance of LEDs must be within specified limits (1). It is necessary to identify LEDs that are insensitive to high energy irradiation (4).…”

“…Effects of verity of radiations including gamma rays, electrons, neutrons, and protons are reported in the literature (1)(2)(3)(4)(5)(6)(7)(8). However, we see no report displaying the effects of gamma radiation particularly on I-V and Intensity-Power characteristics of RGB LEDs in the dose range 1.8 kGy to 172.8 kGy.…”

Epitaxial growth of semiconductor alloys by computational modeling

“…One of the fundamental characteristics of InGaN is its direct band gap (Eg), which can be adjusted from values of 0.65 eV (infrared) to 3.42 eV (ultraviolet), passing through the violet-blue, green, and yellow spectral region, depending on the molar fraction of indium (indicated by the subscript x in the stoichiometric formula) in compound [4]. Other important characteristics are the high mobility of the n-type carrier, resistance to radiation, and the optical absorption of the order of 10 5 cm À1 near the edge of the band [5,6]. Figure 1 shows the bandgap versus the lattice constant of the compound, as well as the regions of the visible light spectrum, where solid lines represent the ternary values.…”