Discrete and Monolithic Phase-Change Material (PCM) Radio Frequency (RF) Switches with Sheet of Thermally Conductive and Electrically Insulating Material

A radio frequency (RF) device includes a phase-change material (PCM) situated over a sheet of thermally conductive and electrically insulating material, a heating element situated under the sheet of thermally conductive and electrically insulating material, and an input/output terminal situated over the PCM. The heating element is situated in a dielectric. A heat spreader is situated under the dielectric and over a substrate. Metal interconnect layers can be situated under and/or over the PCM, with the substrate situated below the metal interconnect layers.