Electrical technique for monitoring crack growth in thin-film fracture mechanics specimens

An accurate and reliable electrical technique for continuous monitoring of crack growth in fracture specimens containing technologically relevant thin-film device structures has been developed. Both adhesive and cohesive crack growth measurements are reported using a SiO₂passivation layer and a conducting titanium film deposited on the side face of fracture specimens. Crack velocity measurements approaching 10⁻¹²m/s were achieved, representing nearly an order of magnitude improvement over commonly used compliance-based techniques. The technique may be particularly useful for elucidating near threshold crack velocity behavior, which is important for thin-film reliability.