In-situ RHEED studies of YBCO-film growth during pulsed laser deposition

In-situ reflection high-energy electron diffraction (RHEED) measurements during laser ablation of YBa/sub 2/Cu/sub 3/O/sub 7-x/ (YBCO) on SrTiO/sub 3/[100], [305] and on SrTiO/sub 3/[100] misoriented 2 degrees and 3 degrees towards [110] were performed. The specularly reflected electron intensity oscillation is modulated by the laser pulse deposition frequency. The crystallization of the deposited material is directly monitored by an exponential intensity rise of the specular intensity. From the time constant the critical laser repetition frequency can be estimated. Oscillations were not observed during the growth on 3 degrees vicinal SrTiO/sub 3/[100] and on SrTiO/sub 3/[305] substrates. For these substrates well-aligned steps parallel to the [100] direction exist due to growth by step movement. From this a mean diffusion length between 7.5 nm and 11 nm at 720 degrees C was determined.<>