Conformal Metal Grid Patterning for Green Spinel Domes

Soft lithography is an inexpensive and fast method for applying micropatterned structures to both flat and nonplanar substrates. TA&T leverages multiple soft lithographic processing steps to pattern co-fireable refractory metal grid on spinel dome windows for electromagnetic interference (EMI) filtering purposes. In addition to the overall curvature of a green ceramic dome, the surface roughness poses difficulties that preclude many other techniques for applying high fidelity features to a surface. The proposed approach overcomes the technical issues by forming the conductive material grid pattern on a transfer film that can be integrated into the ceramic production process. A micromolding technique which infiltrates a photocurable resin formulated with metal loading into channels which define the grid dimensions is developed to pattern on the film. The complete system of inorganics and organics necessary for the gridding and transparent ceramic production is considered for compatibility. The resulting grid is expected to have low sheet resistance for high EMI shielding performance.