We investigated the synthesis of kesterite Cu2ZnSnS4 (CZTS) thin films using thermal evaporation from copper (Cu), zinc (Zn) and tin (Sn) pellets and post-annealing in a sulfur atmosphere. Two different metal precursor stacking orders (Cu/Sn/Zn/Cu and Cu/Sn/Cu/Zn) have been tested and experimental results prove that a layer of Cu on the top provides higher compositional uniformity and fewer secondary phases. CZTS thin films produced by a Cu/Sn/Zn/Cu precursor stacking order was used to study post rapid thermal annealing (RTA) influence on solar cell performance. The best performing solar cell using the CZTS thin film mentioned above with composition ratio Cu/(Zn+Sn) = 0.82, and Zn/Sn = 1.35 exhibited an open-circuit voltage of 433 mV, a short-circuit current of 7.78 mA/cm2, a fill factor of 46.23 % and a conversion efficiency of 1.56 %. Post RTA was conducted and an increase of device performance was observed. The solar cell which shows 1.56 % at room temperature shows 2.72 % efficiency after RTA at 350 °C for 30 seconds. The cell performance improvement mechanism was studied.
|Original language||English (US)|
|Title of host publication||2015 IEEE 42nd Photovoltaic Specialist Conference, PVSC 2015|
|Publisher||Institute of Electrical and Electronics Engineers Inc.|
|State||Published - Dec 14 2015|
|Event||42nd IEEE Photovoltaic Specialist Conference, PVSC 2015 - New Orleans, United States|
Duration: Jun 14 2015 → Jun 19 2015
|Name||2015 IEEE 42nd Photovoltaic Specialist Conference, PVSC 2015|
|Other||42nd IEEE Photovoltaic Specialist Conference, PVSC 2015|
|Period||6/14/15 → 6/19/15|
Bibliographical notePublisher Copyright:
© 2015 IEEE.
- interfacial defect concentration
- photovoltaic cells
- rapid thermal annealing