This Small Business Innovation Research (SBIR) Phase I project aims to develop commercially viable processes to fabricate low-cost large-area transparent conducting films (TCFs) using solution phase synthesis and self-assembly on both rigid and flexible substrates. Material synthesis, nanomaterial dispersion formulation and deposition techniques will be studied to improve both the transparency and conductivity of the TCFs to be competitive with commonly used transparent conductors such as Indium-Tin-Oxide (ITO).
The broader/commercial impact of this project will be the potential to provide low-cost, highly-conductive and transparent films as a replacement of ITO. Such TCFs can be used in a broad range of commercial applications including liquid crystal displays (LCD), plasma displays, touch screens, organic light emitting diodes (OLEDs), antistatic coatings, electromagnetic interference (EMI) shielding and photovoltaics. The processes and methods to be developed would also improve the understanding of the material interactions at the nanoscale and impact other technical areas such as printing electronics.
The feasibility of our approaches and methods for fabricating TCFs by printing nanoparticle ink has been demonstrated by the Phase 1/1B work. We have successfully achieved the major Phase I/IB research objectives. The major conclusions include: 1) the environmental friendly and cost-effective synthesis process of metal nanoparticles have been successfully scaled up to >1kg/batch; 2) Various approaches to improving the conductivity of TCFs using metal nanoparticle printing have been explored; these combined approaches have been used to fabricate TCFs with desired resistivity especially on flexible substrates; 3) TCFs with ~85% transmittance and <10 W/sq sheet resistance have been manufactured on glass substrates; 4) Additives to improve the stability of the ink and to improve adhesion to substrates have been identified and successfully applied; 5) Large size of TCFs on 18*12 in2 flexible substrates (PET) have been successfully demonstrated. 6) Stability and reliability of the TCFs have been studied. 7) Established strategic partnerships; identified potential investors. 8) The performance of Tecona’s TCF has been tested by a touch screen manufacturer. These conclusions will support our Phase II work because the work in Phase I/IB has laid the foundation for carrying out scale-up manufacturing of the commercially-viable TCFs for touch screen and photovoltaic applications. Such TCFs will be engineered and tailored for the specific requirements of different applications. Further refinements in technical details will be continued and finalized in Phase II. The proof of concept effort gave us confidence that a cost effective and high volume production process for manufacturing TCFs can be developed allowing reducing the total cost of fabrication to be below $10/m2 as compared to ~ $100/m2 for ITO.
