An electronic device, such as a thin-film transistor, includes a substrate and a dielectric layer formed from a dielectric composition. The dielectric composition includes a dielectric material, a crosslinking agent, and an infrared absorbing agent. In particular embodiments, the dielectric material comprises a lower-k dielectric material and a higher-k dielectric polymer. When deposited, the lower-k dielectric material and the higher-k dielectric material form separate phases. The infrared absorbing agent allows the dielectric composition to attain a temperature that is significantly greater than the temperature attained by the substrate during curing. This difference in temperature allows the dielectric layer to be cured at relatively high temperatures and/or shorter time periods, permitting the selection of lower-cost substrate materials that would otherwise be deformed by the curing of the dielectric layer.