IN-LINE UV SPECTROSCOPY OF YBA2CU3O7 MOCVD PRECURSORS

Real-time UV absorbance of YBCO MOCVD precursors was monitored in-line at the bubbler effluent using a remote fiber-optic based dual-wavelen gth detection scheme. A S/N of 50:1 was obtained by signal averaging d etector response over a one second interval. This technique provided a chemical specific measurement of extremely dilute concentrations of M OCVD source materials. In addition, several concentration transients w ere observed. Multi-wavelength detection (PDA/spectrograph) provided f ull spectral information. Bubbler efficiency of Y(thd)(3) was shown to improve as system pressure was increased.