화학공학소재연구정보센터
Materials Science Forum, Vol.338-3, 1503-1506, 2000
Pulsed laser deposition: A novel growth technique for wide-bandgap semiconductor research
The present work describes a novel, relatively simple and efficient technique of pursed laser deposition (PLD) for rapid prototyping of thin films and multilayer heterostructures of wide-bandgap semiconductors and related materials. In this method, a KrF-pulsed excimer laser is used for ablation of polycrystalline, stoichiometric targets of wide-bandgap materials. Upon laser absorption by the target surface, a strong plasma plume is produced, which then condenses onto the substrate, which is kept at a suitable distance from the target surface. We have optimized the processing parameters, such as laser fluence, substrate temperature, background gas pressure, target to substrate distance, and pulse repetition rate, for the growth of high-quality thin films and heterostructures of AlN, GaN, and their alloys. Application of this technique in the fabrication of high-quality AlN thin films for SiC encapsulation, low-leakage AlN dielectric layers, and epitaxial TSI ohmic contacts for high-temperature SiC-based thyristors is discussed.