Crack-Free,Thick Ceramic Coating Films via Non-Repetitive Dip-Coating using Polyvinylpyrrolidone as Stress-Relaxing Agent

摘要

BaTiO_3 and PZT films were prepared from alkoxide-acetate solutions containing polyvinylpyrrolidone (PVP) by non-repetitive dip-coating. it was demonstrated that PVP incorporated in gel films suppresses crack formation during heating and increases the critical thickness, the maximum thickness achievable without crack formation via single-step deposition. Using PVP crack-free BaTiO_3 and PZT films 1.2 and 0.5 #mu#m in thickness could be prepared, respectively, via single-step dip-coating. The films were fairly transparent and dense in microstructure. The tensile stress in heat-treated BaTiO_3 films was also demonstrated to decrease significantly by incorporating PVP in gel films.