Project Name: High Lifetime and Mobility Cadmium Telluride Alloys by Co-Sublimation
Funding Opportunity: PVRD2
SETO Subprogram: Photovoltaics
Location: Fort Collins, CO
SETO Award Amount: $162,702
Awardee Cost Share: $18,094
Principal Investigator: Walajabad Sampath

This project is investigating the composition and grading of cadmium telluride (CdTe) materials to understand the effects of novel, early-stage fabrication techniques on carrier lifetime, doping levels, and device performance. Materials and device characterization will provide insight into the unique properties of these materials. The project aims to produce improved carrier lifetimes and device performance for CdTe-based devices.

Approach

The research team is focused on the use of advanced fabrication equipment to produce controlled bandgap profiles and improved doping of CdTe films using nitrogen and arsenic, performed using metal organic precursors. Advanced characterization will be used to measure doping levels and dopant incorporation in the films. Microscopic images using transmission electron microscopy will be collected to identify any changes to the microstructure or morphology. The goal is to reach efficiencies of 20.4 percent using the university’s fabrication capabilities and processes, which will be tested with existing and new passivating schemes to achieve maximum cell performance.

Innovation

By further increasing the efficiency of CdTe thin-film photovoltaics without a substantial increase in manufacturing costs, this project will play a key role in reducing the cost of commercial electricity generation. Increases in efficiency will have a wide impact on energy cost, as higher-efficiency commercial modules would produce more energy without the need for more modules. This would result in lower land utilization, lower maintenance costs, fewer hardware requirements, and reduction of all balance of system costs, leading to a substantial reduction in the levelized cost of electricity.