Green and low-cost preparation of CIGSe thin film by a nanocrystals ink based spin-coating method

• Published in: The Korean journal of chemical engineering Vol. 36; no. 12; pp. 2110 - 2117
• Main Authors: Le, Trang Thi Thuy, Le, Nam, Pallavolu, Mohan Reddy, Jeon, Yoonchang, Jeong, Dong-seob, Pejjai, Babu, Reddy, Vasudeva Reddy Minnam, Truong, Nguyen Tam Nguyen, Park, Chinho
• Format: Journal Article
• Language: English
• Published: New York Springer US 01-12-2019; 한국화학공학회
• Subjects: Biotechnology; Catalysis; Chemistry; Chemistry and Materials Science; Electronic; Industrial Chemistry/Chemical Engineering; Inorganic; Materials (Organic; Materials Science; Thin Films; 화학공학; Spin-coating Method; CIGSe Compound; CIGSe Thin Film Solar Cell; Solution Based Process
• ISSN: 0256-1115; 1975-7220
• DOI: 10.1007/s11814-019-0386-8

An “ink” solution based process, using spin-coating technique, followed by annealing in selenium environment with different temperature programs was utilized to prepare CIGSe thin films. Herein, the CuIn
0.7
Ga
0.3
Se
2
nanocrystals were synthesized using ethanol — a “green” solvent. Three different solvents: 2-propanol, 2-methoxyethanol, and their 2: 1 mixture (v/v ratio), were investigated as a dispersion medium for the as-synthesized CIGSe nanocrystals to form a stable ink solution. The last one- a mixture of 2-propanol: 2-methoxyethanol=2: 1 (v/v), was found to be the most suitable. Furthermore, the influences of various annealing modes on the CIGSe grain size and density in the resulting film were also studied. The as-prepared CIGSe thin film was around 1 µm thick and possessed a tetragonal structure. A newly developed cheaper and “greener” non-vacuum process was applied successfully from the synthesis of nanocrystals to the formation of ink solution, and produced high quality thin films; this opens a new route to the cost-competitive commercialization of CIGSe thin film solar cells.