An integrated alcohol microgas sensor was designed and fabricated based on TiO₂/SnO₂ nanocomposites acting as a sensing layer and microheater providing working temperature. The stacked TiO₂/SnO₂ nanocomposites were prepared by magnetron sputtering. A unique suspended membrane consisting of Si₃N₄/SiO₂/Si₃N₄/SiO₂ four layers was prepared by different methods, respectively, and applied in microheater to support the electrodes and sensing layer for reducing power consumption. The fabrication process tackled the difficulty that the sensing layer preparation is incompatible with microelectromechanical systems micromachining technology and realised the mass production of the wafer-level sensor chips with good consistency. The microalcohol sensors showed excellent response characteristics for alcohol (50–600 ppm) detection at low power consumption (39 mW).