Resistivity, adhesive strength, and residual stress measurements of thin film metallizations on single crystal quartz

A study of resistivity, adhesive strength, and residual stress measurements which were made on 450 Å Cr/1800 Å Au and 450 Å Mo/1800 Å Au thin films deposited on optically polished, z-plate single crystal quartz surfaces is discussed. The films were analyzed after deposition and following annealing at 380°C or 450°C for 30 min in either air or vacuum. The resistivity of the Cr/Au film increased by 1090% and 1780% after vacuum annealing at 390°C and 450°C, respectively. These increases were reduced when 1000 Å of Ni or Mo were introduced as barrier layers between the Cr and Au to prevent interdiffusion of the two layers. The resistivity of the Mo/Au films remained unchanged after all annealing exposures. The Cr/Au, Cr/Mo/Au, and Cr/Ni/Au films had adhesion strengths of 41 to 70 MPa in both the as-deposited and annealed conditions. The adhesive strength of the Mo/Au metallization was 23 to 31 MPa except after the 450°C air anneal, where the value dropped to zero. The residual stress of the as-deposited Cr/Au films was 170 MPa (tensile) but became compressive at -120 to -250 MPa after annealing. The Mo/Au metallization was deposited with a zero stress value that also became compressive at -140 to -180 MPa