SBIR Phase I: Advanced Laser Patterning of Large Area Thin-Film Electrochromic Devices

This Small Business Innovation Research (SBIR) Phase I project addresses laser ablation to precisely and selectively pattern multilayer thin-film electrochromic (EC) devices. Shadow masking (best method available today) is problematic for commercial manufacturing because it results in unacceptable edge definition of the coatings and is prohibitively expensive. The other patterning technique, photolithography, is also cost-intensive and can contaminate the films. The objective of this project is to determine if laser processing is capable of economically patterning a large area. The technical challenge is to determine the optimum pulse power density and number of pulses per ablation site to rapidly and cleanly remove only selected coatings without disturbing the electrical isolation of the separate films at patterned edges. This project will build prototypes, which will be used for durability testing. A laser process model to estimate trade-offs among process speed, laser costs, and fixed costs for a mix of window sizes will be constructed. The broader impacts (commercial significance) if successfully, would be a device and software that could significantly reduce manufacturing costs by eliminating the need for mechanical masks. Software driven laser tooling would increase manufacturing throughput by enabling lightning fast changeovers. Moreover, laser ablation will enable EC windows to meet customer requirements-larger glass sizes and greater vision area of the glass-which are critical to a viable marketplace product. These cost savings and product improvements are essential to even begin to reach the $13.8 billion market predicted for EC windows worldwide. A successful project will accelerate broad market penetration and as a consequence enable significant energy savings and other societal benefits to be realized.