The SnO2 and In2O3 powder mixed with different ratio and heated at 9000C about 5 hrs and then this powder is used to
prepared thick films by a screen – printing technique on glass substrate. The NH3 gas sensing properties, particularly the rate of
response of SnO2-In2O3 sensors are studied at room temperature. SEM and EDAX analysis showed that crystallite size is small
(86.43 nm) for 65SnO2-45In2O3 composition. The Sensitivity increases drastically as the expose of NH3 gas for 65SnO2-45In2O3
sample. This sample is found to be better sensing material as regards to other in all respect.
