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Multi-layered stacked dielectric devices provide the mechanism of using resonance cavities, based on Fabry-Perot interferometer theory, for spectral shaping for filtering or beam emission purposes. This thesis describes the completion of two projects to demonstrate the capabilities of such structures. The first focused on the design and fabrication of a stacked dielectric structure to achieve a broadband filtering response at millimeter-wave (mm-wave) frequencies. The measured structure consists of a periodic arrangement of different dielectric materials (aperiodic designs demonstrated in simulation) to exhibit a bandpass (BP) response. These structures are designed using a transmission line (t-line) model and confirmed with full-wave simulations. Compared to standard printed circuit board (PCB) fabrication, stacked dielectric structures are expected to exhibit better loss performance, due to absence of metallic patterns, and are easier to fabricate at mm-waves because of the absence of constraints from PCB line-width/gap dimension tolerances. An example structure was designed, fabricated, and measured with a center frequency 57 GHz consisting of three dielectric slabs and two air gaps. ANSYS FEM-HFSS simulations of this structure show well-matched BP performance, insertion loss of less than 1 dB, and a 3-dB bandwidth of 4.5 GHz. Measurement of the fabricated structure shows excellent performance and correlation with simulation. The second project focused on the design, fabrication, and direct thermal testing of a multi-layer aperiodic all-dielectric thermal emitter, with its high quality factor (Q-factor) and emissivity properties being experimentally demonstrated for carbon dioxide gas sensing applications. Using a 7-layer dielectric stack consisting of alternating layers of silicon and silicon dioxide, backed by a metallic ground plane, an emittance of 0.7 and Q-factor of 113 is achieved at 70°C. This is the first time a direct thermal testing of such a structure is reported, thereby showing narrowband emission properties of such structures when heated above room temperatures. An all-dielectric stack is thus found to be a simple, deposition-based, structure that does not require any lateral mask preparation as the frequency selectivity is achieved using an aperiodic arrangement of alternating dielectrics with contrasting permittivities. For both projects, superior performance of the aperiodic stacked dielectric structures over their periodically stacked counterparts is demonstrated using numerical examples.

Multi-Layer Aperiodic Dielectric Stack Structures for High Performance Electromagnetic Spectral Shaping from mm-Wave to mid-IR Frequencies