INFLUENCE OF HEATING RATE ON THE STRUCTURAL AND OPTICAL PROPERTIES OF SILVER AND GERMANIUM CO-DOPED CZTS THIN FILM

Year 2023, Volume: 4 Issue: 1, 10 - 15, 15.06.2023

Yavuz Atasoy , Ali Çiriş , Mehmet Ali Olğar

https://doi.org/10.55696/ejset.1295349

Abstract

The effect of heating rate on the structural and optical properties of Ag+Ge co-doped CZTS thin film were investigated and compared with the undoped CZTS sample. The undoped and Ag+Ge co-doped CZTS samples obtained by two-stage technique consisting of the sequential deposition of the precursor stacks by sputtering systemand sulfurization of these layers at elevated temperature in the RTP system by employing heating rate of 1°C/s, 2°C/s and 3°C/s. Ag and Ge co-doped precursor stack as well as undoped stack demonstrated Cu-poor, Zn-rich composition. In addition, the dopant ratio of the Ag+Ge co-doped stack was close to the targeted content considering to EDS measurement. Regardless of the employed heating rate or the doping process, all of the samples crystallized in a kesterite structure. However, it was confirmed by XRD measurements that high heating rates caused phase separation in kesterite phase formation. On the other hand, The Raman peaks assigned to Cu-vacancy and CuZn antisite defects formation inhibited with incorporating Ag and Ge into the CZTS structure. Ag and Ge co-doped CZTS sample produced with a heating ramp rate of 1°C/s showed better structural and optical results among them.

Keywords

Ag and Ge co-doping, CZTS Thin Film, Sputtering, Rapid Thermal Processing, Heating Rate

Supporting Institution

Scientific Research Projects Unit of Niğde Ömer Halisdemir University

Project Number

FMT 2022/6-BAGEP

Thanks

This work was supported by grants from Scientific Research Projects Unit of Niğde Ömer Halisdemir University (FMT 2022/6-BAGEP). The authors also thanks to Prof. Dr. RECEP ZAN for his valuable support.

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