Continuous deposition and rapid fabrication of self-epitaxial CeO2 cap layers by PLD method on IBAD buffers

We have fabricated long buffered substrate tapes by a reel-to-reel process. The architecture is a self-epitaxial PLD-CeO₂ cap layer on an IBAD-Gd₂Zr₂O₇ buffered Hastelloy-C 276 tape. At the same time, we have investigated the effect of the deposition temperature for self-epitaxial growth of the PLD-CeO₂ cap layer. We found that a deposition temperature of 500°C for the self-epitaxial PLD-CeO₂ cap layer is the best in the range of 200°C and 800°C for O₂ pressure of 10-30 mTorr in terms of the in-plane grain alignment. At the deposition temperature of 500°C in the reel-to-reel process, we obtained a PLD-CeO₂ cap layer with Δφ values of about 5 degrees at a tape transfer speed of 6 m/h for IBAD-GZO tapes with Δφ values of about 15 degrees in 100 m class long tapes. Furthermore, we also obtained a PLD-CeO₂ cap layer with better Δφ values of 3.7-4.4 degrees at a tape transfer speed of 2 m/h for a 55 m long tape.