Laser ablation deposition as a preparation method for sensor materials

Abstract

Abstract In the development of new materials for sensors, laser ablation deposition (LAD) offers a relatively easy technique to realise complicated material compositions and multilayer structures. In this paper, LAD of three different thin films for sensor and actuator materials was carried out using a Q-switched ND:YAG laser and an XeCl excimer laser. CuInSe 2 (CIS) and Cu(In, Ga)Se 2 (CIGS) are well-established as exceptionally efficient semiconductors with potential applications in the fields of solar cells, infrared radiation monitors and fibre optic infrared detectors. CIS and CIGS thin films were deposited by an in situ process on fused silica and single crystal silicon substrates. The composition of the target material was largely maintained in the thin films. Lead zirconium titanate (PZT) materials are widely used in sensor and actuator applications. Laser ablation has been used to produce piezoelectric thin films for use in a low voltage cantilever bimorph actuator structure. Nd-doped PZT films were deposited on to Ag-coated oxidised silicon substrates. Displacements in the order of microns were obtained from a 15 mm long element. Diamond-like carbon thin films also have potential in sensor applications. By varying the peak power density of the laser beam and the deposition temperature, it was found to be possible to tailor the electrical and optical properties of the deposited films between the extremes of diamond-like and graphite-like carbon.