Magnesium Chloride as flux and binder in the sedimentation deposition of YBa2Cu3O7-δ films
In suspension-based film fabrication techniques, the material synthesis undergo a series of physical and chemical transformation - from suspension deposition until particle sintering. To further improve the process, additives are used to control suspension dynamics during deposition and to enhance particle mobility during heat treatment. A divalent metal chloride salt, magnesium chloride (MgCl2), was used as an additive for fabrication of YBa2Cu3O7−δ (Y123) films to act both as a flux and a binder. The as-deposited Y123 film with 0.05 wt% MgCl2 featured closely-packed particles while the resulting post-annealed film showed large grain formation. The increased particle mobility brought by an increased amount of liquid phase in Y123 films with MgCl2 improved the microstructure formation and enhanced the particle growth in the Y123 films.