NSF Award
1248886
This Small Business Innovation Research Phase I project will develop high speed laser crystallization (HSLC) of solution deposited aluminum-doped zinc oxide (AZO) nanoparticle layers in order to reduce the manufacturing cost of thin film solar cells. AZO is a promising transparent conductive oxide (TCO). Deposition of TCO layers is one of the most expensive steps during the manufacturing process of thin film solar cells. Initial studies has already shown that HSLC crystallization of AZO layers yielded resistivity less than 3 x 10-4 ohms-cm and a maximum mobility of 380 cm2/vs (1-2 orders higher than the other deposition techniques such as sputtering). The proposed work will investigate high speed laser crystallization of AZO nanoparticles inks to prove the viability of high volume production of high performance TCO layers by HSLC of solution deposited nanoparticles. Technical milestones include: TCO deposition process speeds up to 2 orders faster over current techniques, transmission over 90% in 400-1500 nm range, and sheet resistance under 10 ohm/square. Scaling and optimization of the high-speed processes will be demonstrated on multiple large-area cells with a goal of a relative efficiency improvement of > 5% over baseline cells using a sputtered AZO layer.<br/><br/>The broader/ commercial potential of this project will be achieved through new equipment for integration into manufacturing to produce high-efficiency CIGS solar modules. Nearly half of the world?s CIGS solar manufacturing capacity has been established in the U.S. This SBIR development has the potential to improve manufactured CIGS solar cell efficiency by over 5% (relative) and reduce cost per watt by more than 10%. This would aid in moving flexible CIGS solar products into a market lead position, grow U.S. manufacturing, and enable large-scale adoption of solar. Integrating this technology into other PV device stack layers (such as the CIGS absorber layer) as well as the TCO layer, which is the subject of this proposal, could create over $4 billion in economic value annually by 2020. This process also has the potential to improve other commodity thin-film materials such as those used in lightweight paper batteries, organic solid state lighting, flexible displays, and RFID tags.
