Electrical contact performance of MEMS acceleration switch fabricated by UV-LIGA technology

This paper expanded a micro-contact resistance model to investigate the contact performance for a acceleration switch fabricated by UV-LIGA (Ultra-violet Lithographie, Galvanoformung and Abformung) technology. Based on the relationship between the contact radius a and electron mean free path λ, three different contact resistance models have been analyzed. The material properties (elastic modulus E, hardness H and Poisson’s ratio v) and surface topographic parameters (asperity summit radius r, standard deviation of height distribution σ, and surface density of asperity) have been studied to evaluate the contact resistance-load characteristics. The results show that the theoretical prediction of contact resistance-load characteristics correlates well with the experimental results except there exists experimental discrepancy. The discrepancy between theoretical predictions and experimental results mainly is due to the contaminations, errors from assumptions, surface oxidation and external environmental conditions.