Krajewski Maciej, Tokarczyk Mateusz, Świętochowski Piotr, Wróbel Piotr, Kamińska Maria, Drabińska Aneta
Faculty of Physics, University of Warsaw, 02-093 Warsaw, Poland.
ACS Omega. 2023 Aug 9;8(33):30621-30629. doi: 10.1021/acsomega.3c04256. eCollection 2023 Aug 22.
ZnO is a widely studied material that exhibits versatile doping possibilities. Most research presents singly doped ZnO, leaving the potential of codoping unexplored. Within this study, hafnium-aluminum codoped zinc oxide (HAZO) thin films were grown on a glass substrate using the atomic layer deposition technique at 200 °C. A comprehensive analysis of the surface morphology and electrical and optical properties of the samples was conducted for varying the Al/Hf doping ratio. X-ray diffraction studies showed that the obtained films are polycrystalline, exhibiting a preferential growth direction along the (1 0 0) plane without any detectable precipitates. Moreover, the electrical measurements of HAZO films revealed that they exhibit lower resistivity (∼9.5 × 10 Ωcm) than the commonly used aluminum zinc oxide films (AZO). This improvement can be primarily attributed to the promotion of the n-type carrier concentration to 4.45 × 10 cm while maintaining a mobility value equal to 14.7 cm/Vs. The doping also influences the optical properties of the material by widening the band gap and changing the refractive index, as observed by spectroscopy and ellipsometry studies. These findings highlight the potential of proposed HAZO thin films for future applications in electronic devices utilizing transparent conducting oxides.
氧化锌是一种被广泛研究的材料，具有多种掺杂可能性。大多数研究展示的是单掺杂氧化锌，而共掺杂的潜力尚未得到探索。在本研究中，采用原子层沉积技术在200℃的玻璃基板上生长了铪铝共掺杂氧化锌（HAZO）薄膜。针对不同的铝/铪掺杂比例，对样品的表面形态、电学和光学性质进行了全面分析。X射线衍射研究表明，所获得的薄膜是多晶的，沿（1 0 0）平面呈现出择优生长方向，且没有任何可检测到的沉淀物。此外，HAZO薄膜的电学测量结果显示，它们的电阻率（约9.5×10Ω·cm）低于常用的铝锌氧化物薄膜（AZO）。这种改善主要归因于n型载流子浓度提高到4.45×10cm，同时保持迁移率值为14.7cm²/V·s。如光谱和椭偏测量研究所观察到的，掺杂还通过拓宽带隙和改变折射率来影响材料的光学性质。这些发现突出了所提出的HAZO薄膜在利用透明导电氧化物的电子器件未来应用中的潜力。
