Electrical properties of Ag/Ta and Ag/TaN thin-films

Abstract

a b s t r a c tAlthough wide band gap devices (WBG, e.g. GaN and SiC) are eminently suitable for high temperatures and harsh environments, these properties cannot be fully taken advantage of without an appropriate interconnect metallization. In this context, silver shows promise for interconnections at high temperatures. In this work, the thermal stability of Ag with two barrier metals -Ta and TaN -was therefore investigated. Metal stacks, consisting of 100 nm of silver on 45 nm of either Ta or TaN were sputterdeposited on the substrate. Each metal system was annealed in vacuum for one hour at temperatures up to 800°C. Both systems showed stable performance up to 600°C. The system with Ta as a barrier metal was found to be more stable than the TaN system. Above 700°C, silver agglomeration led to degradation of electrical performance.

Understanding the Preferred Crystal Orientation of Sputtered Silver in Ar/N2 Atmosphere: A Microstructure Investigation

“…For example, Ag/GaN multilayer films are used as the conductor electrodes of lightemitting diodes (LEDs), the coatings of laser safety glasses, and display window materials which block microwave radiation [4,5]. Ag/TiN or Ag/TaN multilayer films are potential materials to be used as interconnects on integrated circuits [6][7][8]. Beyond that, Ag/TiN multilayer films are also used in the photocatalytic field [9].…”

Bipolar integrated circuits in SiC for extreme environment operation

“…It was found that Pt has better electromigration properties than Al at high temperatures, but instead suffered from poor step coverage since it was evaporated [10]. Ag and Cu were tested separately as interconnect material, but not in the integrated circuit process [46][47][48].…”

“…Some separate tests have been made on Ag and Cu metallization for SiC integrated circuits. However, the proper use of capping layers of Ta or TaN is critical for both metal systems for use above 600 °C [46][47][48].…”

Cristalización y morfología superficial de películas delgadas de Ag/SiO2 tratadas térmicamente

“…Se ha reportado que el tratamiento térmico mejora la cristalización de las películas metálicas de Ni, Au y Cu cambiando la morfología superficial de estas [6][7][8]. Además se han reportado cambios en la morfología superficial de las películas delgadas de Ag con la adición de impurezas de Cu [9] y después de un recocido térmico [10]. Con el tratamiento térmico se puede conseguir mejorar la cristalización de películas delgadas y mejorar sus propiedades físicas, tales como la adhesión, la conductividad eléctrica, incrementando de esta forma sus potenciales aplicaciones.…”