SBIR Phase I:Potassium Lithium Niobate grown by Modified Laser Heated Pedestal Growth technique for blue and UV laser applications

This Small Business Innovation Research (SBIR) Phase I project will demonstrate the technical feasibility of growing potassium lithium niobate (KLN) frequency doubling crystals for blue and ultraviolet (UV) laser applications. The incorporation of frequency-doubling crystals composed of KLN, a non-linear optical material with desirable properties, has the potential to improve the performance and reduce the cost of blue and UV lasers. However, potassium lithium niobate (KLN) crystals have not entered the commercial mainstream because it is impossible to grow them reproducibly, and with the required performance and cost, by conventional techniques such as the Czochralski method. We have developed a proprietary process based on the laser heated pedestal growth (LHPG) technique that will eliminate the technical barriers to commercializing KLN crystals. In this project, we will determine the precise composition of KLN required for non-critical phase matching at 795 nanometers, optimize the quality of KLN crystals with the required composition, and then maximize the conversion efficiency of KLN crystals by precise doping to increase their transparency. The Phase I technical goal is to create KLN crystals capable of receiving 16 watts of infrared laser power at 795 nm and generating 2 watts of laser power at 397.5 nm.
The broader impact/commercial potential of this project will be the availability of frequency doubling crystals which will improve the performance of UV lasers for inspecting photomasks, and patterned and unpatterned wafers in the semiconductor industry. The market for inspection systems for these applications has grown to 200 systems per year and is valued at $500 million. The KLN crystals to be developed will enable laser manufacturers to commercialize higher-power, more robust, lower-cost UV lasers, in turn enabling semiconductor equipment manufacturers to develop improved inspection and metrology systems. These inspection systems will enable chip makers to commercialize future generations of higher-performance integrated circuits, and to increase their yields. This project will be undertaken in close collaboration with Spectra-Physics, a leading laser manufacturer, which will assist in testing the resulting crystals, allowing us to accelerate market acceptance.