# Overview on Different Types of Solar Cells: An Update
## 5 Thin-Film Solar Cells
### Cu\({}_{2}\)ZnSnS\({}_{4}\) Film Solar Cells  
Copper-zinc-tin sulfide (Cu\({}_{2}\)ZnSnS\({}_{4}\)) films are becoming increasingly prominent for several reasons. These materials could replace indium and gallium in CIGS films, as their constituents are Earth-abundant and do not contain cadmium (toxic material). The experimental results showed that CZTS-based solar cells have an excellent absorption coefficients (more than 10\({}^{4}\) cm\({}^{-1}\)), tunable band gap values (1.45 eV to 1.6 eV), and greater stability in the kesterite phase (Figure 12) when compared with stannite and wurtzite. Researchers have reported that vacuum and non-vacuum deposition techniques have been used to produce CZTS films (Table 4). Further, they concluded that high-quality filmscould be synthesized using the vacuum-deposition method; however, this entails increased production costs.  
\begin{table}
\begin{tabular}{c c c c c c} \hline \multirow{2}{*}{**Deposition Technique**} & \multicolumn{5}{c}{**Photovoltaic Properties**} & \multirow{2}{*}{**Reference**} \\ \cline{2-2} \cline{4-5}  & **V\({}_{\text{oc}}\) (mV)** & **I\({}_{\text{sc}}\) (mA/cm\({}^{\text{2}}\))** & **PEC (\%)** & **FF (\%)** & \\ \hline Electro deposition & 723 & 18.7 & 8.6 & 64 & [175] \\ \hline Electro deposition & 700 & 18.1 & 6 & - & [176] \\ \hline Electro deposition & 250–290 & 4.12–6.35 & 0.28–0.92 & 25–52 & [177] \\ \hline Thermal-evaporation method & 519 & 18.19 & 6.4 & 45.6 & [178] \\ \hline Evaporation method & 863 & 27.1 & 18.7 & 80.5 & [179] \\ \hline Glancing angle-deposition method & 774 & 23 & 11 & 61.9 & [180] \\ \hline Vapor-transport deposition & 806–839 & 20.2–21.6 & 12.5–13.5 & 73.3–76.9 & [181] \\ \hline Vapor-transport deposition & 683–839 & 22.2–22.9 & 9.2–14.4 & 60.6–75 & [182] \\ \hline Sputtering method & - & - & 11.2 & - & [183] \\ \hline Radio-frequency sputtering & - & - & 14 & - & [184] \\ \hline Laser-ablation method & 600 & 13 & 3 & 40 & [185] \\ \hline Pulsed-laser deposition & - & - & 6.68 & - & [186] \\ \hline \end{tabular}
\end{table}
Table 2: The growth of CdTe films using various deposition methods and the photovoltaic properties.  
\begin{table}
\begin{tabular}{c c c c c c} \hline \multirow{2}{*}{**Deposition Technique**} & \multicolumn{5}{c}{**Photovoltaic Properties**} & \multirow{2}{*}{**Reference**} \\ \cline{2-2} \cline{4-5}  & **V\({}_{\text{oc}}\) (mV)** & **I\({}_{\text{sc}}\) (mA/cm\({}^{\text{2}}\))** & **PEC (\%)** & **FF (\%)** & \\ \hline Co-evaporation method & - & - & 6.46–9.78 & - & [187] \\ \hline chemical bath deposition method & 760 & 0.059 & 0.011 & 25.1 & [188] \\ \hline Co-sputtering method & 551–553 & 22.7–29.5 & 9.1–11.1 & 68.4–72.3 & [189] \\ \hline Vacuum evaporation method & 712 & 34.8 & 18.7 & 75.7 & [190] \\ \hline Chemical vapor deposition & - & - & 9.91 & 64.75 & [191] \\ \hline Spin-coating method & - & - & 10 & - & [192] \\ \hline Sputtering and evaporation method & - & - & 20.4 & - & [193] \\ \hline Vacuum evaporation & - & - & 17.1 & - & [194] \\ \hline Co-precipitation method & 168.2 & 8.11 & 0.4 & 27.6 & [195] \\ \hline Inkjet printing method & 386 & 29.78 & 5.04 & 44 & [196] \\ \hline Evaporation method & - & - & 10.6 & - & [197] \\ \hline Electro-deposition method & - & - & 9.4 & - & [198] \\ \hline Electro-deposition method & 666 & 30.5 & 15.4 & 75.6 & [199] \\ \hline Electro-deposition method & 413 & 32.5 & 6.6 & 49 & [200] \\ \hline Electro-deposition method & 741 & 23.2 & 10.2 & 59.6 & [201] \\ \hline Electro-deposition method & - & - & 4 & - & [202] \\ \hline Electro-deposition method & - & - & 4.5 & - & [203] \\ \hline Electro-deposition method & - & - & 1.63 & - & [204] \\ \hline Electro-deposition method & - & 0.143–0.376 & 0.079–0.403 & 0.384–0.526 & [205] \\ \hline DC-magnetron sputtering method & 553 & 30.18 & 11.28 & 68 & [206] \\ \hline \end{tabular}
\end{table}
Table 3: The growth of CIGS films using various deposition methods and the photovoltaic properties.