Control system for the synthesis of thin films by pulsed laser deposition

CONDE GARRIDO JM; KUO, CRISTINA; SILVEYRA JM

IEEE LATIN AMERICA TRANSACTIONS

IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC

Lugar: New York; Año: 2020 p. 438 - 445

1548-0992

The pulsed laser ablationprocess is a widely used technique for thin films deposition. In this method, apulsed laser beam focuses onto a target ablating the impact site, called spot. Sincepreparing the target is a highly time consuming and expensive task, the spot isgenerally scanned across the target?s surface. A typical pulsed laserdeposition configuration has a moving mirror that scans the laser beam across arotating target. We propose ablating the target with a spiral pattern to ensurea uniform ablation and maximizing the target?s efficiency. This requires movingthe mirror and target in sync with variable speeds. To this end, we designedand built robust electromechanical actuators driven by stepper motors, whichare electronically controlled by an Arduino-based system. The core of thefirmware is a precalculated lookup table with the time intervals between themotors? steps. Thus, motor control following computationally expensive positioningfunctions -as the spiral pattern- are not a problem. Users may operate thecontrol system through a user-friendly interface. The modular firmware architecturefacilitates future extensions as, for example, adding other motor positioning functionsto enable different ablation patterns for research purposes. This development aimsto be a valuable tool for the synthesis of thin films by pulsed laserdeposition.