Direct Electrospray Printing of Gradient Refractive Index Chalcogenide Glass Films

TitleDirect Electrospray Printing of Gradient Refractive Index Chalcogenide Glass Films
Publication TypeJournal Article
Year of Publication2017
AuthorsNovak, S, Lin, PTai, Li, C, Lumdee, C, Hu, J, Agarwal, A, Kik, PG, Deng, W, Richardson, K
JournalAcs Applied Materials & Interfaces
Pagination26990 - 26995
Date Published2017/08/16/
ISBN Number1944-8244
Keywordsannealing conditions, chalcogenide glass, electrospray, gradient refractive index, microphotonics, structural-properties, Thin Films, thin-films

A spatially varying effective refractive index gradient using chalcogenide glass layers is printed on a silicon wafer using an optimized electrospray (ES) deposition process. Using solution-derived glass precursors, IR-transparent Ge23Sb7S70 and As40S60 glass films of programmed thickness are fabricated to yield a bilayer structure, resulting in an effective gradient refractive index (GRIN) film. Optical and compositional analysis tools confirm the optical and physical nature of the gradient in the resulting high-optical-quality films, demonstrating the power of direct printing of multi material structures compatible with planar photonic fabrication protocols. The potential application of such tailorable materials and structures as they relate to the enhancement of sensitivity in chalcogenide glass based planar chemical sensor device design is presented. This method, applicable to a broad cross section of glass compositions, shows promise in directly depositing GRIN films with tunable refractive index profiles for bulk and planar optical components and devices.

Short TitleACS Appl. Mater. Interfaces