Capacitive And Inductive Effects In Resistors Induced By Diffusion

Resistive layers are often used as gas sensors. During the measurements the contaminating gas diffuses into the layer while changing its resistivity. If one measures the impedance of the resistors for various frequencies, one often obtains an impedance plot which can be modelled by an equivalent network involving capacitances and inductances. Although a resistive layer does not show any intrinsic capacitive or inductive properties, it will be shown theoretically here that a diffusion process can give rise to such phenomena