Spin-coated kesterite CZTS thin films for photovoltaic applications

Abstract

Copper zinc tin-sulfide (CZTS) films have been widely studied over recent years due to the inherent advantages of low cost, high absorption coefficient (≥ 10 4 cm −1 ), suitable band gap (∼1.5 eV) and nontoxicity. In this work, spin coating was used to obtain CZTS films of various compositions and degrees of crystallization on glass substrates, which were then annealed at 500 • C in a N2 atmosphere by using a rapid thermal processing (RTP) furnace in order to optimize their structure. Non-stoichiometric precursors and low spinning speeds resulted in a lower sheet resistance, which is considered to be a result of lower degree of crystallization. Furthermore, the non-stoichiometric films had a high optical band gap (> 1.66 eV) whereas the band gap of the stoichiometric films (1.4 to 1.6 eV) was close to the optimal value (1.5 eV) for solar-cell applications.

Advancement of stannite Cu2CoSnS4 thin films deposited by sol gel dip-coating route

“…The high electrical sheet resistance observed in films can be due to a few voids and cracks in the surface morphology. These values are comparable to those cited by other research groups[45][46][47]. The values of electrical conductivity are ranging from 0.11 to 0.21 W…”

Current Status of the Open-Circuit Voltage of Kesterite CZTS Absorber Layers for Photovoltaic Applications—Part I, a Review

“…The CZTS precursor solution is synthetized by dissolving the elements raw precursors in 2-methoxyethanol (C 3 H 8 O 2 ), i.e., a salt of copper (for Cu), a salt of zinc (for Zn), a salt of tin (for Sn), and thiourea (NH 2 ) 2 CS (for S). The 2-methoxyethanol solvent removes the necessity to perform prolonged low-temperature processing of the deposited solution on the substrate after spin-coating (110 °C ÷ 120 °C temperature annealing for 80 ÷ 120 min), which not only significantly increases the fabrication time of the CZTS film at the optimal thickness (around 1 µm) but also favors the formation of undesirable oxide compounds in CZTS films, and thus results in the low reproducibility of the electrical and optical parameters [ 64 , 65 , 66 , 67 ]. Dimethyl sulfoxide (DMSO) has been successfully used for the synthesis of the precursor solution and spin-coating of CZTS films.…”

Properties of ITO thin films rapid thermally annealed in different exposures of nitrogen gas

“…Demands for energy materials that are readily available, low cost, and easy to process have led to the development of novel optoelectronics and solar cells materials [1][2][3][4][5][6]. Application of such materials on the commonly used electrodes for optoelectronic devices needs further research to achieve such devices best performance.…”