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Organic electro-optic (EO) molecules have several advantages over incumbent inorganic EO materials, and are slated to be used in modulators for much faster next-generation fiber-op¬tic telecommunications networks if their performance can be further improved. Here we investigate increasing the efficiency of EO molecules and utilizing materials that are more suitable for modulator devices. Organic EO molecules in this application must first be aligned. Alignment is typically done by a process called electric field poling, where a thin film of organic EO material is placed between two electrodes and a strong electric field is applied, causing the molecules to reorient. We use chromophore molecules at high number density to produce higher EO coefficients (r33), which is the figure of merit for comparing EO molecules. However, because of their high degree of conjugation (delocalized electron sharing), these molecules can have significant leakage current during poling, reducing the electric field and thus the degree of molecular alignment. Although solvent-cast charge barrier layers have been successful in reducing current in parallel plate test devices, they cannot be applied as conformal (consistent in depth) coatings in the microscopic trenches in real world silicon modulators. We hypothesized that four new types of charge barrier layers could meet this requirement: phenylphosphonic acid self-assembled monolayer (SAM), 4-cyanobenzoic acid SAM, aminopropylphosphonic acid SAM, and layer-by-layer (LbL) films of poly(sodium styrene sulfonate)/poly(diallyldimethylammonium) chloride. We discuss fabrication methods as well as effects of barrier layers on r33, on conductance during poling, and on EO thickness and roughness.