A novel gas sensor based on micro-machined ceramic hot-plate and wire-free bonding is presented to overcome the shortcomings of high power consumption and packaging difficulty existing in the current commercial ceramic gas sensors.The Pt heater and contact electrodes were sputtered on alumina substrate by controlled lift-off processing.The devices with different parameters were fabricated using the laser micro-machining technique.The performance of the hot-plate was tested and evaluated from the...