Effect of Silver Addition on the Sodium Amount and the Grain Size of the Chalcopyrite Thin Films Deposited on Different Back Contact Materials

---

Ağca S.

International Conference on Engineering Technologies (ICENTE'23), Konya, Türkiye, 23 - 25 Kasım 2023, ss.1, (Özet Bildiri)

• Yayın Türü: Bildiri / Özet Bildiri
• Basıldığı Şehir: Konya
• Basıldığı Ülke: Türkiye
• Sayfa Sayıları: ss.1
• Ankara Yıldırım Beyazıt Üniversitesi Adresli: Evet

Özet

In this study, the effect of silver addition on the sodium amount and the grain size of chalcopyrite thin films was investigated. Soda lime glass was used as substrate which was the source of sodium. The sodium was diffused from soda lime glass to chalcopyrite thin film through the back contact material. Different back contact materials were used to understand the effect of back contact material on the diffusion mechanism of the sodium. Molybdenum and ITO back contact layers around 500 nm were deposited on the soda lime glass by RF magnetron sputtering. Cu(In_0.7Ga_0.3)Se₂ and (Ag_0.5Cu_0.5)(In_0.7Ga_0.3)Se₂ chalcopyrite thin films were deposited by physical vapor deposition both on molybdenum and ITO back contacts at actual temperatures of 420℃ and 560℃ to understand the effect of silver addition and the temperature difference.

The chemical composition of chalcopyrite thin films were obtained by energy dispersive X-ray spectroscopy. The microstructure photoes were taken by scanning electron microscope. The amount of sodium through the thickness of the samples was investigated by glow discharge optical emission spectroscopy. The results showed that the addition of silver increased the average grain size for both low and high process temperatures. However, it has been observed that the silver effect is more effective at higher temperatures. The average grain sizes of Cu(In_0.7Ga_0.3)Se₂ and (Ag_0.5Cu_0.5)(In_0.7Ga_0.3)Se₂ chalcopyrite thin films produced at 420℃ were 500 nm and 950 nm, respectively. On the other hand, the addition of silver has increased the average grain size of the thin film from 750 nm to 2 μm. These results also showed that the temperature increase has a positive effect on the average grain size. Although there are partial differences, it has been determined that the amount of sodium generally increases after silver addition. At low temperature, the amount of sodium in Cu(In_0.7Ga_0.3)Se₂ thin film deposited on molybdenum were higher than the one deposited on ITO back contact. After the addition of silver, the amount of sodium in the (Ag_0.5Cu_0.5)(In_0.7Ga_0.3)Se₂ sample with ITO back contact became higher than that of with molybdenum back contact. Furthermore, at high temperature, the amount of sodium in the samples with molybdenum back contact were higher than that of ITO back contact for both Cu(In_0.7Ga_0.3)Se₂ and (Ag_0.5Cu_0.5)(In_0.7Ga_0.3)Se₂ chalcopyrite thin films. At the same time, the effect of silver on the sodium amount were more pronounced in the sample with molybdenum back contact. As a coclusion, it is found that the temperature, back contact material, average grain size, and the silver addition had an effect on the amount of the sodium in the chalcopyrite thin films. All these parameters should be optimized to be able to get the appropriate amount of sodium.