Superconducing YBa2Cu3O7−xfilms were prepared by pulsed CO2laser deposition. Correlations between target composition and microstructure, and film composition, morphology, and uniformity were made in order to understand the process by which film growth occurs. Auger spectroscopy of the molten globules produced by laser deposition showed the globules to be compositionally nonuniform with Y depletion at the surface, and enrichment inside the globule. Evaporated Cu and Ba were detected in the films. After annealing the films, both Cu rich and Ba rich surface areas were detected, but the overall composition of the film was YBa2Cu3O7−x.