For thermal resistance measuring applications, State of the Art (SOTA) Inc. is offering a line of microwave self-heating sensor chips that use platinum on alumina and oxidized silicon. The heater/sensors are suitable for use in applications from microelectronics to biomedical engineering, including determination of thermal resistance of integrated circuit chips, variable optical attenuation of arrayed waveguide gratings, and thermal management in miniature chambers (minicell arrays). The TM365 model has two thermal sensors near the heater for stringent temperature control, and the TM364 single-sensor design provides moderate temperature control. Both operate at up to 250 °C. Self-heating is below 4 mW/°C. Custom designs can be developed based on customer drawings.