Diamond-like carbon (DLC) films are considered to be excellent materials due to their outstanding physical and chemical characteristics. In this study, unbalanced magnetron radio frequency sputtering system was employed to prepare DLC films at room temperature. The effects of working power on properties of the as-deposited films were discussed. The surface property of the DLC films were analyzed by field emission scanning electron microscopy (FE-SEM) and scanning probe microscopy (SPM). The microstructure of the films were studied using Raman spectroscopy and element spectroscopy for chemical analysis (ESCA). The working power were found to have significant effects on sp3/sp2 fraction ratio of the DLC films. Also, the films deposited under 150 W possessed uniform surface morphology, high sp3 content and low surface roughness of 0.542 nm. In order to investigate the effects of sp3 bonding on the photoconductivity of the DLC films, the as-prepared films with different sp3/sp2 ratio were employed as absorption layer for UV detector with various electrode materials (Au, Ag, and Ti). The UV photoresponse measurement results shown that the DLC/Ti had fast response to UV irradiation (rise time and fall time of 0.13 and 0.2 sec, respectively) with high photo-dark current ratio in air ambient of 2.6 order.