SBIR Phase I: Nanoparticle Te Inks for Spray Deposition of Submicron Te Contact Layers in CdTe Solar Cells

This Small Business Innovation Research (SBIR) Phase I project addresses the need for a non-vacuum deposition approach for contact layers in CdTe solar cells. While sputtering is at present successfully employed, the objective of this project is the development of a nanoparticle ink that could be used to print submicron thick Te thin films. To date, Te inks produce non-uniform coatings owing to particle agglomeration. The research objective of this project is the formulation of a Te ink composed of dispersed, nonagglomerated Te particles with diameter less than 50 nm. The efficacy of this ink will be demonstrated by fabrication of CdTe solar cells as follows. First, the Te ink will be sprayed onto the CdTe layer of a solar cell heterostructure. Then, this green body will be subjected to a thermal treatment. Finally, the solar cell will be finished by deposition of an opaque electrode. Characterization will be performed on the ink, the sprayed layers, and the finished CdTe devices. If successfully developed, it is anticipated that this research would be translated to a production-sized (i.e., 100 megawatt) CdTe solar cell facility through the industrial subcontractor of this project