Laser assisted magnetron sputter deposition with ultrashort pulses

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The fabrication of thin films and nanostructures can be realized through various techniques. This enables the tailoring of materials including their optical, electrical, and magnetic properties. Among the various approaches, sputtering is a physical vapour deposition technique which is based on ions colliding with a target from which material is detached and deposited on a substrate. In magnetron sputtering (MS), an electromagnetic field confined near the surface of the target is used to ionize the inert gas and to create a**plasma, from which ions are produced and accelerated to bombard the target materials from which high quality uniform thin films are obtained. While the rate of deposition scales with the number of ions, it is tempting of using a high pressure of inert gas, but this comes at the costs of low quality films in terms of structure and density. Therefore, the limiting factor for MS is a low rate of deposition thus limiting the industrial applications of this technique.****Over the recent years, our industrial partner Plasmionique Inc. has developed, in collaboration with INRS-EMT researchers, a hybrid technique called MS/PLD (Pulsed Laser Deposition). They have demonstrated that combining MS with a 20 Hz nanosecond UV laser interacting with the target allows the retention of a high rate of deposition while keeping the pressure sufficiently low enough to enable high quality films. As the fluence needed to reach the ablation threshold is reduced at lower pulse duration, with the inverse of the square root of the pulse duration (down to 1 picosecond - ps - pulse duration), we hypothesize that MS/PLD will benefit from**the use of ultrashort pulses for triggering and maintaining the magnetron discharge. Using ultrafast laser systems, we will study MS/PLD with ultrashort pulses from 0.04 to 10 ps. Furthermore, ultrashort pulsed laser are operated at much high repetition rate, thus offering the possibility of studying the scaling of MS/PLD to higher laser repetition rate for increasing the rate of deposition (e.g. 5 kHz vs 20 Hz represents a factor of 125).