| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 1666231 | Thin Solid Films | 2013 | 4 Pages |
In order to investigate alternative absorber materials for inorganic solar cells, thin films of bismuth trisulfide (Bi2S3) were deposited under high vacuum conditions by the thermal evaporation method from compound material. The effects of the substrate temperature during deposition on the structural, stoichiometric, optical and electrical properties were investigated. Polycrystalline thin films close to an ideal stoichiometry could be deposited for temperatures TSub = 80–290 °C; thereby a transition from rough needle-shaped particles with (hk0)-orientation parallel to the surface of the substrate towards block shaped grains with a preferred direction out of the surface could be observed. Confocal photoluminescence measurements revealed an optical pseudo band-gap of 1.32–1.36 eV and additionally a homogeneous lateral dependence in the optical properties of the thin films. By in-plane transport measurements, an increase of the conductivity was observed from 2 ⋅ 10− 7Ω− 1 cm− 1 for amorphous/microcrystalline films up to 2.5–8.5 ⋅ 10− 3Ω− 1 cm− 1 for polycrystalline films deposited above 250 °C.
► Polycrystalline Bi2S3 thin films were grown by physical vapor deposition. ► The films were close to stoichiometry even for elevated substrate temperatures. ► Two growth regimes of Bi2S3 could be identified. ► Photoluminescence spectra show increase of yield with rising substrate temperature. ► Our findings suggest solar cell preparation at temperatures of at least 240 °C.
