Proceedings of International Conference Asia-Pacific Hybrid and Organic Photovoltaics (AP-HOPV17)
Publication date: 7th November 2016
Organic-inorganic lead halide perovskite compounds have attracted much attention as a material for solar cells due to their strong light absorption coefficient, high carrier mobility, low binding energy of excitons, and tunable band gap. Additionally, the perovskite compounds can be synthesized using inexpensive sources, suggesting that high performance and inexpensive solar cells are achievable. However, perovskite solar cells, which are usually fabricated by a solution process, have poor stability against moisture because the perovskite compounds are ionic crystals, and sensitive to moisture incorporation from the solvent. As a consequence solution processes face big challenges to become a suitable process for the fabrication of perovskite solar cells on large areas in mass production scale. There have been a few reports on the fabrication of perovskite solar cells using dry processes such as vapor phase deposition or pulsed laser deposition. In this work, we propose fabrication of perovskite solar cells by sputtering, which is more suitable for large scale fabrication. We present results on the fabrication of perovskite films by sputtering and their characterization.
PbI2 target was fabricated from PbI2 powder using a pressing machine under 10 MPa. Then, PbI2 films were fabricated on glass substrates by RF sputtering using the PbI2 target. To obtain perovskite films, sputtered PbI2 films were annealed at 100oC in CH3NH3I gas filled petri dish. XRD measurement and SEM observation were carried out to characterize the fabricated perovskite films.
From the XRD measurement, clear diffraction patterns of CH3NH3PbI3 perovskite were confirmed in the films. SEM observations show that the substrates are entirely covered with perovskite grains. We applied these films for perovskite solar cells and successfully obtained photovoltaics performance from sputter processed perovskite films.