Improving the Photovoltaic (PV) efficiency of Solar Grade Silicon

Abstract

The minority carrier lifetime (MCL) is one of the main deciding factors for the efficiency of Si solar cells. Grown-in micro-defects (GMD) are responsible for limiting the MCL by acting as recombination centers. Si solar cell doped with Boron (B) has low MCL and hence low efficiency.Whereas gallium (Ga)-doped Si has high MCL. When a third element, say tetravalent Ge is co-doped in B doped or Ga doped Si, interesting properties are observed. The formation mechanism of GMD , the effect of Ge on GMD and hence on MCL and efficiency in Si is not fully understood. In this project we propose to investigate theoretically, using Density Functional Theory (DFT), the band structure, the charge distribution, the formation mechanism of GMDs and the mechanism by which the Ge-concentration suppresses GMD and influences the trapping and MCL in B/Ga doped Si crystal. We investigate the percentage of Ge that is sufficient for controlling the GMD and enhancing the PV characteristics of Si. We also explore the other dopants and co-dopants similar to B, Ga and Ge.

Document Details

Document Type
DoD Grant Award
Publication Date
Feb 07, 2017
Source ID
N629091512035

Entities

People

  • Kombiah Iyakutti

Organizations

  • Office of Naval Research
  • SRM Institute of Science and Technology
  • United States Navy

Tags

Fields of Study

  • Materials science

Readers

  • Groundwater Contamination Remediation.
  • Semiconductor Device Technology
  • Solar Photovoltaics and Thermoelectric Devices.

Technology Areas

  • Microelectronics