HgCdTe thin films were deposited on Si (1 1 1) substrates at different target-substrate separations by pulsed laser deposition (PLD). The results show that the kinetic energy of the incident particles, and the thickness, crystallinity, elemental composition and surface morphology of the HgCdTe thin films are affected by the change of the target-substrate separation. The HgCdTe films prepared using Nd:YAG laser show cubic phase. The films prepared by PLO on the undoped Si substrates can form SiTe4 between the HgCdTe film and the Si substrate at small target-substrate separation distance. The formation of interfacial Si-Te may affect the quality of PLD HgCdTe thin films on Si substrates. (C) 2009 Elsevier B.V. All rights reserved.