Non-monotonic effect of growth temperature on carrier collection in SnS solar cells

• Main Authors: Yang, C. (Author), Gordon, R. G. (Author), Chakraborty, Rupak (Contributor), Steinmann, Vera (Contributor), Mangan, Niall Mari (Contributor), Brandt, Riley E (Contributor), Poindexter, Jeremy Roger (Contributor), Jaramillo, Rafael (Contributor), Mailoa, Jonathan P (Contributor), Hartman, Katherine (Contributor), Polizzotti, James Alexander (Contributor), Buonassisi, Anthony (Contributor)
• Other Authors: Massachusetts Institute of Technology. Department of Mechanical Engineering (Contributor)
• Format: Article
• Language: English
• Published: AIP Publishing, 2018-10-01T15:11:19Z.
• Subjects: Article
• Online Access: Get fulltext

 We quantify the effects of growth temperature on material and device properties of thermally evaporated SnS thin-films and test structures. Grain size, Hall mobility, and majority-carrier concentration monotonically increase with growth temperature. However, the charge collection as measured by the long-wavelength contribution to short-circuit current exhibits a non-monotonic behavior: the collection decreases with increased growth temperature from 150 °C to 240 °C and then recovers at 285 °C. Fits to the experimental internal quantum efficiency using an opto-electronic model indicate that the non-monotonic behavior of charge-carrier collection can be explained by a transition from drift- to diffusion-assisted components of carrier collection. The results show a promising increase in the extracted minority-carrier diffusion length at the highest growth temperature of 285 °C. These findings illustrate how coupled mechanisms can affect early stage device development, highlighting the critical role of direct materials property measurements and simulation.