Automation of pulsed laser deposition

Abstract

The Pulsed Laser Deposition (PLD) growth process uses a target of a given material and a substrate located within a vacuum chamber. A UV laser beam scans the target to produce a plasma which coats the substrate. Sensors for the vacuum chamber, with a data acquisition channel, are coupled to a process control computer. The bus is also coupled to a mirror gimbal control for directing the laser beam on the target. The process control provides for initializing a PLD instrumentation system, opening a data file, controlling deposit of a PLD film, determining when a desired deposition time or thickness is completed and then shutting down the laser, and closing the data file. Automation of PLD provides automatic instrumentation setup and real time automatic collection of the process variables, total vacuum quality, mass spectroscopy vacuum partial pressure, molybdenum I ionized species and bulk thickness deposition rate, as well as providing a methodology of ensuring uniform process health prior to making a deposition. Sensors are used to remotely monitor the status of the process, thus avoiding operator exposure to harmful UV rays produced by the pulsed high energy eximer laser. Automation of PLD also provides a uniform method of setting up the PLD process, to ensure similar process initial conditions prior to deposition.