Zero Net Stress Coating Method for X-Ray Mirrors

X-ray mirrors formed with zero net stress are sought for next generation space optical systems. Existing thin film deposition methods such as sputtering or atomic layer deposition each have inherent difficulties in repeatedly achieving a zero stress state at reasonable cost and throughput. Skyhaven Systems proposes to develop a deposition method to produce the desired mirror. The method is fundamentally easy to apply, economical, and readily scaled. The process is performed at ambient pressure and is expected to provide a uniform, smooth, and adherent coating. The Phase I effort will lead to demonstrating the deposition method by producing an iridium mirror with negligible stress. The coating will be evaluated for stress level, thickness, uniformity, surface roughness and adhesion. The Phase II effort is envisioned to: further improve and characterize the coating's properties in terms of process capability and environmental stability, to scale the fabrication process, and to supply full-scale coated substrates to NASA for evaluation. More »