SBIR-STTR Award

Reflective optics for short-wavelength applications are required having ultrasmooth finishes, with rms roughness in the range below 10 angstroms. Typically this is achieved by extensive figuring and superpolishing of bulk samples or deposited thin films, an expensive and time-consuming process. SKION proposes to employ its unique negative metal ion beam deposition (NMIBD) technique to fabricate high quality reflective optics with a super smooth finish without the need for a final polishing step. The need for polishing is eliminated because NMIBD films actually become smoother during deposition, unlike conventional film deposition processes. This innovation will make possible the fabrication of mirrors which not only avoid the above-mentioned problems, but which also can be deposited at lower temperatures than many techniques such as CVD, thus reducing cracking and distortion, and enabling deposition on less expensive low temperature substrates. SKION's unique ion beam deposition process can achieve a breakthrough in the fabrication of high-energy short wavelength reflective optics with better performance at lowered cost. SKION has recently developed the only commercially available large area ion beam source, which will be adapted and utilized for this program.

Benefits:
Successful completion of this program will provide new technology applicable to many military and commercial optical needs for space-based and synchrotron radiation optics as well as optical components for laser welding, drilling, and other high-power uses

In the Phase I program, SKION demonstrated the capability of Negative Sputter Ion Deposition to deposit optical thin films with state-of-the-art properties, specifically ultrasmooth surfaces, high packing density, refractive index close to bulk values, and stability to environmental exposure. In Phase II, we propose to utilize these films to fabricate high-quality, economical optical devices for high energy laser applications. Prototype dielectric mirrors will be delivered which have higher reflectivity, lower loss, and higher laser damage threshold than currently available technology, with lower projected costs per unit. SKION will accomplish these goals with a threefold program: technology demonstrations in collaboration with two well-renowned laboratories, design and construction of a flexible multilayer deposition system, and fabrication and testing of state-of-the-art devices. Dielectric mirrors will be fabricated using tantalum oxide and silicon oxide, two of the optical thin film materials demonstrated in Phase I. The target application will be a high reflectance mirror at the YAG wavelength (1.06 microns) with high laser damage threshold. SKION will meet with the Army to discuss the most desirable configurations and alternate or additional devices to be delivered. The devices developed in the Phase II program will be scaled up for commercial production.

Keywords:
ION BEAM DEPOSITION, THIN FILMS, MIRROR, HIGH ENERGY LASER, LASER DAMAGE THRESHOLD, MULTILAYERS, ULTRASMOOTH FILMS