Microstructural analysis and modeling of RuO₂ thin film resistors

The microstructural properties of RuO₂ thin film resistors with different temperature coefficients of resistance (TCRs) were analyzed using X-ray diffraction, scanning electron microscopu and Auger electron spectroscopy. A model based on microstructure of the films was developed to explain the experimental results, such as the negative, positive and near-zero TCRs of the resistors. The grain size controlled the resistivity of the resistors. However, the chemical composition of the film was more likely to control the TCR of the resistors. A layer-like structyre was required to fabricate near-zero-TCR resistors. The modeling based on the electrical measurement of the resistors provided valuable guidance in designing and fabricating near-zero-TCR resistors.