Structural and optical properties of phosphorous doped nanocrystalline silicon deposited using a VHF PECVD process for silicon heterojunction solar cells and optimization of a simple p-n junction cell using SCAP-1D tool.

Initially hydrogenated silicon (Si:H) thin films have been deposited using a plasma-enhanced chemical vapor deposition technique (PECVD) using silane (SiH) as a precursor gas diluted in an inert gas argon (Ar) environment. Subsequently phosphine gas (PH) was used as the n-type dopant and the deposition was carried out at a fixed substrate temperature of 200 °C. The PH flow rate was varied in the range of 0-1 sccm.

Excited state and charge transfer dynamics in gas phase molecule of CHNHPbI: first-principles study.

In this work, to probe the charge transfer mechanism of methylammonium lead triiodide (CHNHPbI), we have used density functional theory (DFT) and time-dependent density functional theory (TDDFT). We investigate ground and excited states optimized geometry, UV-vis spectrum and vibrational frequencies of CHNHPbI molecule. It is observed that in an excited state, the structural change is mostly localized in PbI part of the molecule.