In the present work, alumina gel was developed for passivating silicon wafers. The alumina gel was prepared by sol–gel method with aluminum sec-butoxide as precursor. After coating, rapid thermal process (RTP) was conducted to activate the passivation effect. X-ray photoelectron spectroscopy and C–V curve were executed to evaluate film properties. The peak at 74.35 eV confirmed the formation of Al₂O₃. Meanwhile, a small peak at low binding energy decreased with the growth of annealing temperature, which was ascribed to the escape of hydrogen, leading to the decline of effective lifetime after 700 °C. The highest fixed charge (Q_f) of − 1.16e12 cm⁻² and superior interface defect density at mid gap (D_it) of 1.98e12 cm⁻²eV⁻¹ were obtained at the annealing temperature of 700 °C, contributing to the highest effective minority carrier lifetime of 292 µs. The present work will be helpful to provide a more cost-effective technique for Al₂O₃ passivation.

中文翻译：

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通过旋涂法沉积的氧化铝膜用于硅晶片表面钝化

在本工作中，开发了用于钝化硅晶片的氧化铝凝胶。氧化铝凝胶是通过溶胶-凝胶法以仲丁醇铝为前体制备的。涂覆后，进行快速热处理（RTP）以激活钝化效果。用X射线光电子能谱和C–V曲线评估膜的性能。74.35 eV处的峰证实了Al ₂ O ₃的形成。同时，随着退火温度的升高，低结合能下的一个小峰减小，这归因于氢的逸出，导致700℃后的有效寿命下降。最高固定电荷（Q _f）为-1.16e12 cm ^-2，中间隙处的界面缺陷密度更高（D _it在700℃的退火温度下获得1.98e12 cm ^-2 eV ^-1），从而有助于使最高有效少数载流子寿命达到292 µs。目前的工作将有助于为Al ₂ O ₃钝化提供更具成本效益的技术。