Preparation of Cu2ZnSnSe4thin films by selenization of stacked metallic layers

Autor: Shang-En Liu, Hou-Ying Huang
Rok vydání: 2013
Předmět:
Zdroj: The European Physical Journal Applied Physics. 64:30302
ISSN: 1286-0050
1286-0042
DOI: 10.1051/epjap/2013130425
Popis: A Cu 2 ZnSnSe 4 (CZTSe) thin film fabricated by selenization of stacked pure metal precursors through e-beam evaporation on Mo-coated soda lime glass substrates worked as thin film solar cell absorber. The selenization was carried out under element Se vapor circumstance at 570 °C for 20 min. The absorber went through chemical bath CdS deposition, sputtered ZnO, ITO and Al electrodes to become a solar cell. Unlike previous works, only simple three-layer metal precursors without any compound were used as evaporation sources. The synthesized CZTSe absorber layer phase was identified by X-ray diffraction. The solar cells were measured by AAA class solar simulator. The absorber layer thickness was measured by scanning electron microscope (SEM). Energy dispersive spectrometer (EDS) was also used for checking metal ratios in the absorber layer. The best efficiency was 4.2%. In this work, we found that there were voids in absorber film bottom. The Cu-top precursors will lead to larger grains, flatter surfaces and larger voids than Sn-top precursors. The Cu-top precursor may also contribute to better selenization which may help prevent Zn loss but cause Sn loss. Finally, this work also showed Cu-poor and Zn-rich will improve conversion efficiency.
Databáze: OpenAIRE