Displacement damage dose analysis of the output characteristics of In0.5Ga0.5P and Cu(In,Ga)(S,Se)2 solar cells irradiated with alpha ray simulated helium ions

To investigate applicability of radiation-hard indium–gallium–phosphide (InGaP) and copper–indium–gallium–sulfide–selenide (CIGS) solar cells to dosimeter devices without any modification, we irradiated high-energy He+ ions, which were simulated α-ray particles, to an InGaP and a CIGS solar cell. We found that both types of solar cells have sufficient resistance to He+ ions. By using displacement damage dose (DDD) analysis, the obtained He+ ion-induced degradation trends were compared with those induced by high-energy electrons, and we found that the degradation trends due to He+-ions, electrons, and protons aligned on the same curve when we plotted the data as a function of a modified DDD conversion equation, which originally was applied to space solar cells. The obtained DDD formulas enable us to predict the device lifetime or correction of an output signal for degradation when such solar cells are employed as a dosimeter.

The synergies between displacement damage creation and hydrogen presence: the effect of D ion energy and flux

In this work the synergism between displacement damage creation and presence of hydrogen isotopes was studied. Tungsten samples were irradiated by 10.8 MeV W ions with or without the presence of D ions with two different energies of 300 eV/D and 1000 eV/D and different temperatures. In order to compare the results obtained with different exposure parameters the samples were afterwards additionally exposed to D ions at 450 K to populate the created defects. By increasing the W irradiation time, ion flux and energy, the increase of D concentration and D retention was observed as measured by nuclear reaction analysis and thermal desorption spectroscopy. By fitting the D depth profiles and D desorption spectra by the rate equation code MHIMS-R we could see that additional fill-levels were populated with higher flux and ion energy which ends up in higher final D concentration and retention as compared to experiments with lower D flux and energy.

Displacement damage effects in proton irradiated vertical-cavity surface-emitting lasers

The displacement damage effects of vertical-cavity surface-emitting lasers (VCSELs) irradiated by 3 and 10 MeV protons in the range of Ф = 6.7×1012 p/cm2 to Ф = 1.6×1014 p/cm2 were investigated. The threshold current exhibited consistent degradation at the same displacement damage dose, as did the series resistance. Additionally, the external quantum efficiencies of 850 and 680 nm VCSELs were degraded by 2% and 21%, respectively. Further, the threshold current of the 850 nm VCSEL was restored by 14% after annealing at 20 mA, which is remarkably higher than that achieved by annealing only at high temperatures. These results support the applicability of VCSELs to both data communication and instrumentation applications in harsh radiation environments.

Molecular dynamics study on single particle displacement damage of ZB InN

To evaluate single-particle initial displacement damage of InN, the MD method is used to simulate the cascades, where the energy of PKA (E PKA) ranges from 1 to 5 keV. From these results, we can find that high EPKA will increase Np and Ns of defects, and aggravate the damage of InN, which is more obvious in Frenkel pairs. The formation efficiency of vacancy and interstitial is influenced by antisite defects, thereby causing the difference between vacancies and interstitials for the same atomic type. About the distribution of InN defects, it is mainly caused by vacancy defects, indicating that vacancy damage occupies the main position in displacement damage.