Pulsed laser deposition of high purity TiN thin films

摘要

TiN thin films were deposited on glass substrates by KrF excimer laser ablation of Ti in very broad N{sub}2 pressure range with different target-substrate distance at room temperature. The as-deposited TIN thin films were analyzed by x-raydiffraction and transmission electron microscopy. It is found that normally the as-deposited thin films are the mixture of TiN and Ti and the ratio of TiN to Ti of the as-deposited thin film depends on both the N{sub}2 pressure and the target-substratedistance. The high purity TiN thin films can be obtained only in a very narrow deposition parameter range. A compound parameter (the product of the N{sub}2 pressure and the target-substrate distance) is proposed to optimize deposition for high purity TiNthin films and the possible mechanism is also discussed. It is also revealed that the as-deposited TiN thin films were polycrystalline with an average grain size about 20nm.