Performance improvement of square microhotplate with insulation layer and heater geometry

In this paper, we investigate four different heater geometries viz. Meander, S-shape, Double-Meander and Double-Spiral for their inherent thermal uniformity. Microheater with optimum dimensions of insulation layer is employed to decrease the layer deposition time and to improve the thermal uniformity. Simulation studies are carried out to find the optimum dimension of insulation layer, required for a targeted uniformity of 0.22 K/mu m, a value comparable to the reported literature. Meander heater with 8 mu m nitride layer has resulted in an uniformity value of 0.174 K/mu m, whereas, a S-shape heater with 4 mu m nitride layer has resulted in an uniformity value of 0.161 K/mu m. With silicon carbide (SiC) layer, only a 0.8 mu m thick layer is required to obtain an uniformity of 0.166 K/mu m. The combination of two methods i.e, the choice of suitable heater geometry plus optimization of insulation layer dimensions, has served the purpose of electrical insulation while improving the thermal uniformity and reducing the insulation layer thickness, all at a nominal increment (7.1%) in power consumption.