Simultaneous Thin‐Film Stress and Mass‐Change Measurements Using Quartz Resonators

摘要: It is shown theoretically and experimentally that stresses in a thin film on quartz resonator surface can set up sufficient static mechanical bias the to cause measurable shifts resonant frequency through finite strain effects. In particular, it found if 5‐MHz AT‐cut fundamental mode 6.19‐MHz BT‐cut are subjected same combination of thin‐film stress mass/cm2 changes their surfaces, sum observed proportional change alone, difference integral thickness alone. This ``double‐resonator'' technique demonstrated with implantation studies 220‐keV 84Kr implants into Si films deposited flat electrodes planoconvex resonators. The double‐resonator results were verified quantitatively by implanting ions one cantilever beam monitoring movement free end capacitance between fixed electrode. sensitivity 125 dyn/cm 6 × 1014 amu/cm2 for 0.1‐Hz shift. suited best small mass changes.