Image processing plume fluence for superconducting thin-film depositions

Process control is a crucial element in all deposition techniques. It is es pecially elusive in the versatile and efficient deposition technique known as pulsed-laser-deposition (PLD). PLD produces a plume of highly energetic components which is directed onto a suitable substrate for growing required films. Image processed plume emissions from a YBa2Cu3O7-x target are in si tu monitored at 553.5 nm to determine two-dimensional spatial information a bout the plume. Simultaneously, time-of-flight (TOF) information also at 55 3.5 nm is gathered from two positions along the plume path. Manual and fuzz y-logic based regulation of laser beam energy based on this TOF feedback ha s resulted in improved film quality and reproducibility. Imaging of the plu me under various deposition conditions, both with and without process contr ol; will help to improve the understanding of changing environmental condit ions on the plume characteristics growth and quality. Published by Elsevier Science Ltd.