Study of interfacial reactions in ionized metal plasma (IMP) deposited Al-0.5%wt Cu/Ti/SiO₂Si structure

Interfacial reactions in Al-0.5%wtCu/Ti/SiO₂Si structure have been investigated up to the annealing temperature of 600°C for 30 min in Argon ambient. Annealing temperature at above 500°C, Al alloy and Ti start to react and produce Al₃Ti, which was already reported. Annealing at higher temperatures (550°C, and 600°C) made Al₃ Ti transformed into Al₅Ti₂, which is thermodynamically more stable than Al₃Ti. The unreacted 52 nm thick Ti which existed underneath of Al₅Ti₂ might lead to retardation of the reaction between Al₅Ti₂ and the underlying SiO₂. Hence, the formation of ternary compound (Al_xTi_ySi_z) which is believed to be detrimental to the contact metallization layers was protected.