Experimental Investigation of Pulsed Laser Deposition Based on a Compressible Flow Framework
Pulsed laser deposition (PLD) is a popular technique for creating thin films. The film characteristics are directly related to the kinetic energy of the laser-induced plume. According to the theory of transient shock wave expansion during laser ablation, laser-induced plume properties are strongly affected by laser intensity as well as ambient temperature, pressure, and gas species. This theory leads to the development of PLD strategies to properly optimize the PLD parameters. The experiments were carried out to deposit diamond-like carbon (DLC) thin films under different ambient temperature, pressure and gas species. The deposited DLC thin films were characterized by Raman spectroscopy. Experimental results showed that the thin film quality can be improved by decreasing the ambient temperature, increasing the ambient pressure and using ambient gases with low molecular weight. Experimental results agree well with the theoretical prediction.