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

Abstract

A study of resistivity, adhesive strength, and residual stress measurements which were made on 450 AA Cr/1800 AA Au and 450 AA Mo/1800 AA 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 degrees C or 450 degrees 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 degrees C and 450 degrees C, respectively. These increases were reduced when 1000 AA 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 degrees 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. >