In recent years

micro-hotplate（ MHP） is widely used to make thermal sensors

heating compo-nents

infrared emitters

and power generators. In MHP application

its own thermal characteristics is one of the important factors that affect device performance and as well as the heat transfer characteristics of gas gap between heating electrode and substrate is a key factor affecting thermal characteristics of MHP. Using standard CMOS technology and simple post-CMOS process

a MHP with sectional area of 35 μm × 35 μm and thickness of 550 nm air gap is designed. Using self-heating effect of MHP

thermal conductance of gas gap is measured in thermal steady state.The results show that gas gap conductance is 6. 74 × 10- 5W / Km and the overall conductance is 7. 51 × 10- 5W /Km

which indicates that gas gap conductance dominates the heat loss of MHP.