Abstract Aluminum-gallium oxide (AGO) films on c-plane sapphire substrates by pulsed laser deposition are described. Both nitrogen and oxygen annealing effects on the structural and optical properties of AGO films are investigated. The AGO film shows an amorphous structure when deposited at low temperatures (≤400 °C) while a crystalline structure at 800 °C. After post annealing at 900 °C, an amorphous-to-crystalline phase transformation for the 400°C-deposited film occurs and shows the preferred β phase. The corresponding optical bandgap also increases from 5.14 eV to 5.41–5.46 eV depending on the annealing ambience. From Raman measurements, the 800°C-deposited AGO sample possesses a more stable O–Ga–O bonding compared to that of the 400°C-deposited one after annealing. Unusually, an evident increase in the nitrogen content is observed for the samples after post annealing at 900 °C in nitrogen atmosphere. The rapid dissociation of oxygen atoms may accelerate the disintegration of crystals and rearrangement, which makes the AGO film adsorb nitrogen atoms and cause the grain size to be significantly reduced. However, the extent of the nitrogen incorporation seems to have no apparent effect on the optical properties. All the AGO films show the optical transmittance over 80% in the ultraviolet–visible region with the calculated bandgaps more than 5.4 eV. Details of the mechanism about the nitrogen incorporation into the annealed AGO films via the oxygen vacancies or micro-pores will be discussed.

中文翻译：

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氮氧退火对脉冲激光沉积法生长的铝镓氧化物薄膜性能的影响

摘要 描述了通过脉冲激光沉积在 c 面蓝宝石衬底上形成的铝镓氧化物 (AGO) 薄膜。研究了氮和氧退火对 AGO 薄膜结构和光学性能的影响。AGO 薄膜在低温 (≤400 °C) 下沉积时显示出非晶结构，而在 800 °C 下沉积时显示出晶体结构。在 900°C 后退火后，400°C 沉积膜发生非晶到结晶的相变，并显示出优选的 β 相。根据退火环境，相应的光学带隙也从 5.14 eV 增加到 5.41-5.46 eV。根据拉曼测量，与退火后 400°C 沉积的样品相比，800°C 沉积的 AGO 样品具有更稳定的 O-Ga-O 键合。不同寻常的是，在氮气氛中在 900 °C 后退火后，观察到样品的氮含量明显增加。氧原子的快速解离可能会加速晶体的解体和重排，使AGO薄膜吸附氮原子并导致晶粒尺寸显着减小。然而，氮掺入的程度似乎对光学性质没有明显影响。所有 AGO 薄膜在紫外-可见光区域均显示出超过 80% 的透光率，计算出的带隙超过 5.4 eV。将讨论关于氮通过氧空位或微孔掺入退火 AGO 薄膜的机制的细节。氧原子的快速解离可能会加速晶体的解体和重排，使AGO薄膜吸附氮原子并导致晶粒尺寸显着减小。然而，氮掺入的程度似乎对光学性质没有明显影响。所有 AGO 薄膜在紫外-可见光区域均显示出超过 80% 的透光率，计算出的带隙超过 5.4 eV。将讨论关于氮通过氧空位或微孔掺入退火 AGO 薄膜的机制的细节。氧原子的快速解离可能会加速晶体的解体和重排，使AGO薄膜吸附氮原子并导致晶粒尺寸显着减小。然而，氮掺入的程度似乎对光学性质没有明显影响。所有 AGO 薄膜在紫外-可见光区域均显示出超过 80% 的光学透射率，计算出的带隙超过 5.4 eV。将讨论关于氮通过氧空位或微孔掺入退火 AGO 薄膜的机制的细节。所有 AGO 薄膜在紫外-可见光区域均显示出超过 80% 的透光率，计算出的带隙超过 5.4 eV。将讨论关于氮通过氧空位或微孔掺入退火 AGO 薄膜的机制的细节。所有 AGO 薄膜在紫外-可见光区域均显示出超过 80% 的光学透射率，计算出的带隙超过 5.4 eV。将讨论关于氮通过氧空位或微孔掺入退火 AGO 薄膜的机制的细节。