Fabrication and electrical properties of YBa2Cu3O7-x thin film prepared by Sol-gel method for uncooled infrared detectors

Abstract

In this study, we fabricated the semiconducting YBCO thin film by sol-gel method. Precursor solution had been fabricated using Y acetate, Ba hydroxide and Cu acetate as starting materials, and propionic acid (PPA) and propylamine (PA) as solvent. The YBCO precursor solution was passed through a syringe filter and spin-coated on the SiO2-coated Si substrate using a spinner operated at 3,000 rpm for 20 sec. YBCO thin films were dried at 500 degrees C for 2 h and annealed at 750 degrees C for 1 h. Then, the structural and electrical characteristics of YBCO thin films were measured with a variation of solvent ratios. The films PPA/PA at 8 : 1 showed the more obvious YBa2Cu3O7-x phase and tetragonal phase. The thickness of all the films was approximately 250 similar to 330 nm and the average grain size of the YBCO thin films PPA/PA at 8 : 1 was about 60 nm. Temperature resistance coefficient (TCR), responsivity and detectivity of the YBCO thin films PPA/PA at 8 : 1 were -3.3%/K at room temperature, 15.94 V/W and 2.44 x 10(6) cmHz1/2/W, respectively.