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Author: Ali Kosari Mehr
Firstly employed by Smith and Turner for thin-film deposition, pulsed laser deposition (PLD) is a technique developed from thermal processes, deployed for depositing alloy/compound thin films. In this regard, a high-power pulsed laser (e.g., the KrF excimer laser) and a quartz lens are two essential parts of the technique: the role of the laser is to cause the irradiation of a target, and the role of the quartz lens is to magnify the laser power over the surface of the target. In this technique, reaching a vapor phase by ablation or evaporation, atoms of the target are deposited on a close substrate; the picture shows a typical system. Moreover, not only is this process comprised of thermal processes but also it may consist of plasma processes. Mainly, the laser causes the local evaporation of the target in the vacuum. However, photo-emitted electrons may result from the high-power laser pulse, forming a plasma plume.
Among the advantages of this technique are its simple design and the compatibility with various forms of the target (e.g., single crystal, powder, sintered components, etc.). Nonetheless, for the time being, there are some limitations: the fairly small area in which the film is uniform and the possible deposition of particles or micro-sized globules. Circumventing the latter limitation, one can place the substrate in an off-axis position [1].
