The effect of stress on the resistivity of submicron aluminum lines

Abstract

The stress coefficient of resistivity (piezoresistance coefficient) of passivated submicron Al-Cu lines was determined using a wafer-bending technique. This coefficient is significant for the interpretation of early resistance changes in reliability lifetime measurements. At room temperature the effect of stress on the resistivity of the lines is negligible. From 110 to 200 °C the piezoresistance coefficient is roughly constant at (Δρ/ρ)/Δσ∼1.2×10−5 MPa−1. Resistance changes associated with stress relaxation in the vicinity of a stress-induced void will be discussed.