Artificial control for nucleation and growth rate of YBa2Cu3O7-δ coated conductors prepared by low fluorine chemical solution deposition.

The influence of various gas flow conditions on the nucleation and growth rate of YBa 2 Cu 3 O 7-δ (YBCO) coated conductors in the high-temperature heat treatment stage of low fluorine chemical solution deposition (LF–MOD) process have been investigated, including the gas flow rate and gas flow direction. The results indicated that film-growth rate is faster while a -axis oriented phase coexisted with c -axis in the films at the higher gas flow rate. And YBCO ( 00 l) grains grew slowly while a -axis oriented phase also nucleated easily on the end of the long films along gas flow direction. It could be caused by large quantities of HF gas accumulating from the chemical reaction for converting YBCO phase. Hence, the crystal mechanism of various LF–MOD methods can be supposed as still “BaF 2 ” process as the TFA-MOD method, and orientation nucleation and growth rate of YBCO films can be artificial control by adjusting the gas flow conditions. [ABSTRACT FROM AUTHOR]