Effect of Annealing Temperature on Spatial Atomic Layer Deposited Titanium Oxide and Its Application in Perovskite Solar Cells
Chia-Hsun Hsu,
Ka-Te Chen,
Pao-Hsun Huang,
Wan-Yu Wu,
Xiao-Ying Zhang,
Chen Wang,
Lu-Sheng Liang,
Peng Gao,
Yu Qiu,
Shui-Yang Lien,
Zhan-Bo Su,
Zi-Rong Chen,
Wen-Zhang Zhu
Affiliations
Chia-Hsun Hsu
School of Opto-electronic and Communication Engineering, Xiamen University of Technology, Xiamen 361024, China
Ka-Te Chen
School of Opto-electronic and Communication Engineering, Xiamen University of Technology, Xiamen 361024, China
Pao-Hsun Huang
School of Information Engineering, Jimei University, Xiamen 361021, China
Wan-Yu Wu
Department of Materials Science and Engineering, Da-Yeh University, Changhua 51591, Taiwan
Xiao-Ying Zhang
School of Opto-electronic and Communication Engineering, Xiamen University of Technology, Xiamen 361024, China
Chen Wang
School of Opto-electronic and Communication Engineering, Xiamen University of Technology, Xiamen 361024, China
Lu-Sheng Liang
CAS Key Laboratory of Design a Assembly of Functional Nanostructures, and Fujian Provincial Key Laboratory of Nanomaterials, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou 350002, China
Peng Gao
CAS Key Laboratory of Design a Assembly of Functional Nanostructures, and Fujian Provincial Key Laboratory of Nanomaterials, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou 350002, China
Yu Qiu
Key Laboratory of Green Perovskites Application of Fujian Province Universities, Fujian Jiangxia University, Fuzhou 350108, China
Shui-Yang Lien
School of Opto-electronic and Communication Engineering, Xiamen University of Technology, Xiamen 361024, China
Zhan-Bo Su
School of Opto-electronic and Communication Engineering, Xiamen University of Technology, Xiamen 361024, China
Zi-Rong Chen
School of Opto-electronic and Communication Engineering, Xiamen University of Technology, Xiamen 361024, China
Wen-Zhang Zhu
School of Opto-electronic and Communication Engineering, Xiamen University of Technology, Xiamen 361024, China
In this study, spatial atomic layer deposition (sALD) is employed to prepare titanium dioxide (TiO2) thin films by using titanium tetraisopropoxide and water as metal and water precursors, respectively. The post-annealing temperature is varied to investigate its effect on the properties of the TiO2 films. The experimental results show that the sALD TiO2 has a similar deposition rate per cycle to other ALD processes using oxygen plasma or ozone oxidant, implying that the growth is limited by titanium tetraisopropoxide steric hindrance. The structure of the as-deposited sALD TiO2 films is amorphous and changes to polycrystalline anatase at the annealing temperature of 450 °C. All the sALD TiO2 films have a low absorption coefficient at the level of 10−3 cm−1 at wavelengths greater than 500 nm. The annealing temperatures of 550 °C are expected to have a high compactness, evaluated by the refractive index and x-ray photoelectron spectrometer measurements. Finally, the 550 °C-annealed sALD TiO2 film with a thickness of ~8 nm is applied to perovskite solar cells as a compact electron transport layer. The significantly enhanced open-circuit voltage and conversion efficiency demonstrate the great potential of the sALD TiO2 compact layer in perovskite solar cell applications.
