Miniaturization of thick–film resistors by laser–shaping

This paper presents manufacturing process of laser-shaped thick-film resistors as well as their chosen electrical, geometrical, microstructural and stability properties. Test structures were based on commercially available conductive and resistive pastes deposited on Al2O3 substrates. Resistors made in standard screen printing process after firing were patterned using laser beam in order to minimize their planar dimensions to tenths of millimeter and below. Prepared samples were subjected to number of electrical tests and some characteristic parameters like temperature coefficient of resistance (TCR) were calculated based on these measurements. Test samples were also exposed to long-term thermal ageing. Moreover the laser profilometer was used for three-dimensional characterization of components. Scanning electron microscope (SEM) was used for the microstructural analysis and the EDS (Energy Dispersive X-ray Spectroscopy) of samples is given.