MULTILAYER FILMS OF TIC, TI AND CU FOR THE GRAVITY-PROBE-B RELATIVITYMISSION GYROSCOPES

Single-component and multilayer films of TiC, Ti and Cu have been prod uced by sputtering on fused quarts substrates and have been investigat ed for suitability as electrodes for the electrostatically suspended g yroscopes of Gravity Probe B. The main requirements for these films ar e low electron field emission in fields of 3 x 10(7) V m(-1), low film stress, and good thermal and electrical conductivity in the temperatu re range 2 K-400 K. The films have been studied using X-roy diffractio n, scanning electron microscopy (SEM), Auger electron spectroscopy, Ru therford backscattering spectrometry, and four-point resistivity techn iques. SEM measurements indicate that the TiC films have very smooth s urfaces and that multilayer films of TIG. Ti and Cu have reduced rough ness as compared with the Ti-Cu multilayer films. Seven-layer 2.5 mu m thick Ti-Cu films have been successfully used in the Gravity Probe B gyroscopes, meeting all requirements. Multilayer films of TiC, Ti and Cu are at present being tested with the expectation that they will fur ther improve gyroscope performance.