This paper describes fabrication and properties of polycrystalline 3C-SiC micro heaters built on AlN(0.1 μm)/3C-SiC(1.0 μm) suspended membranes using surface micromachining technology. 3C-SiC and AlN semiconductors which have a large energy band gap and very low lattice mismatch were used as sensors in harsh environment micro electromechanical system (MEMS) applications in this work. The 3C-SiC thin film was simultaneously used as a resistance of temperature detector (RTD) and micro heater for detecting heated temperature correctly. The thermal coefficient of resistance (TCR) of the implemented 3C-SiC RTD is about -5200 ppm/°C in the temperature range from 25°C to 50°C and -1040 ppm/°C at 500°C. The 3C-SiC micro heater generates about 500°C of heat at 10.3 mW. Moreover, 3C-SiC micro heaters stand at higher applied voltages than case of Pt micro heaters.