The thermal management of integrated sensor has not received much attention so far. The importance of temperature uniformity and the ability to sense accurately the operating temperature of the thin-film sensor have been overlooked. While integrated sensor aims at precision measurement of concentration, the operating temperature of the thin film sensor should be uniform. Highly non uniform temperature profile gives rise to ambiguity of the operating temperature. It will also degrade selectivity and sensitivity. Hence it becomes essential to optimize the microheater resistor geometry in order to achieve a uniform temperature in the active area. © IAEME Publication.