Since the 1970’s, the most well-established and mature type of metallization on commercially available solar cells has been screen-printed silver. The simplicity and low cost of screen printing make it the metallization method of choice for the established industry. The screen-printed solar cells are also cost-effective to produce on large scale. A vital step in the screen-printing process is to maintain cross-sectional profiles of the printed metal gridlines on each individual solar cell. The ideal profile is generally rectangular with a high aspect ratio (height-to-width ratio), although a triangular profile can be advantageous for light trapping. While many commercially available options exist today for screen-printable silver pate, a precise, consistent method for controlling the printed profile is needed to further increase the cell efficiency.
Researchers at the University of New Mexico have developed the capability to precisely control the sheer-thinning behavior of silver pastes, enabling ease of screen printing solar cells and the ability to maintain any desired cross-sectional profile. This capability is achieved by adding carbon nanotubes into a commercial silver paste product. Improved mechanical strength of printed and fired metal gridlines from enhanced sintering of silver particles in the paste is an added benefit. The addition of carbon nanotubes offers additional rheological control over printability and cross-sectional shape control while making the printed gridlines fracture tolerant for increased reliability. The researchers have also formulated a new silver paste that shows much-improved contact resistance, compared to an existing commercial silver paste product.
- Easier screen printing process
- Provides an accurate and consistent cross-sectional profile
- Exhibits enhanced mechanical strength of printed gridlines
- Offers a new silver paste with improved contact resistance
- Large-scale screen-printed solar cells
- Silver paste
- Conductive ink
UNM Rainforest Innovations has filed intellectual property on this exciting new technology and is currently exploring commercialization options. If you are interested in information about this or other technologies, please contact Arlene Young at firstname.lastname@example.org or 505-272-7886.
About UNM Rainforest Innovations
As the technology-transfer and economic-development organization for the University of New Mexico, UNM Rainforest Innovations protects and commercializes technologies developed at the University of New Mexico (UNM) by filing patents and copyrights and transferring the technologies to the marketplace. We connect the business community (companies, entrepreneurs, and investors) to these UNM technologies for licensing opportunities and the creation of startup companies. Visit http://innovations.unm.edu/
Name: Andrew Roerick