In this study, annealing of deep level (EL2) defect in gallium arsenide (GaAs) nanostructures by argon ion beam irradiation has been reported. GaAs nanodots of diameter ranging from 15 to 22 nm were deposited on silicon substrates using the ions of GaAs generated by hot, dense and extremely non-equilibrium argon plasma in a modified dense plasma focus device. GaAs nanodots thus obtained were irradiated by $$\hbox {Ar}^{2+}$$ Ar 2 + ion beam of energy 200 keV with varying ion fluences from $$1 \times 10^{13 }$$ 1 × 10 13 to $$5 \times 10^{15}$$ 5 × 10 15 ions $$\hbox {cm}^{-2}$$ cm - 2 in the low energy ion-beam facility. The ion-beam irradiation transformed the as-deposited GaAs nanodots into uniform GaAs nanostructured films of thickness $$\sim $$ ∼ 30 nm. The obtained nanostructured films are polycrystalline with paucity of arsenic antisite (EL2) deep level defect. The excess arsenic present in the as-deposited GaAs nanodots is the main cause of EL2 defect. Raman and photoluminescence measurements of GaAs nanostructured films indicates removal of excess arsenic, which was present in as-deposited GaAs nanodots, thereby suggesting annealing of EL2 defect from the ion-irradiated GaAs nanostructured films. The change in conductivity type from n- to p-type obtained from Hall measurement further confirms annealing of EL2 defects. The ion-irradiated GaAs nanostructured films have low leakage current due to removal of defects as obtained in current–voltage study, which corroborate the annealing of EL2 defect. The defect-free GaAs nanostructured films thus obtained have potential applications in fabrication of highly efficient optoelectronic and electronic devices.

中文翻译：

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离子束辐照GaAs纳米结构缺陷退火研究

在这项研究中，已经报道了通过氩离子束辐照对砷化镓 (GaAs) 纳米结构中的深能级 (EL2) 缺陷进行退火。直径范围为 15 至 22 nm 的 GaAs 纳米点被沉积在硅衬底上，使用由热、致密和极不平衡的氩等离子体在改进的致密等离子体聚焦装置中产生的 GaAs 离子。由此获得的 GaAs 纳米点被 $$\hbox {Ar}^{2+}$$ Ar 2 + 能量为 200 keV 的离子束照射，离子通量从 $$1 \times 10^{13 }$$ 1 × 10 13到 $$5 \times 10^{15}$$ 5 × 10 15 个离子 $$\hbox {cm}^{-2}$$ cm - 2 在低能离子束设施中。离子束辐照将沉积的 GaAs 纳米点转化为厚度为 $$\sim $$ ~ 30 nm 的均匀 GaAs 纳米结构薄膜。获得的纳米结构薄膜是多晶的，缺乏砷反位 (EL2) 深能级缺陷。沉积的 GaAs 纳米点中存在的过量砷是 EL2 缺陷的主要原因。GaAs 纳米结构薄膜的拉曼和光致发光测量表明去除了沉积的 GaAs 纳米点中存在的过量砷，从而表明离子辐照 GaAs 纳米结构薄膜的 EL2 缺陷已被退火。从霍尔测量获得的导电类型从 n 型到 p 型的变化进一步证实了 EL2 缺陷的退火。由于去除了电流-电压研究中获得的缺陷，离子照射的 GaAs 纳米结构薄膜具有低漏电流，这证实了 EL2 缺陷的退火。