Zinc oxide thin films with different boron doping levels (ZnO:B) are prepared by low pressure chemical vapor deposition (LPCVD) technique. All films here exhibit a pyramid-like surface texture. Stability of the ZnO:B films is systematically investigated through a post heat treatment at ambient temperatures of 300 degrees C and 250 degrees C for different durations. It is found that total transmission (TT) of these films at near infrared (NIR) wavelength range increases with the enhanced thermal treating intensity, which could be attributed to decrease of free carrier concentration inside the films. Moreover, light absorption in NIR wavelength range decreases profoundly with the increasing carrier concentration after a post thermal treatment in particular for highly doped ZnO:B films. However, morphology of these ZnO:B films does not vary after the thermal treatment and thus the corresponding light scattering properties do not change as well. Therefore, the thermally treated ZnO:B films may lead to an increase in light-generated current and resulting a higher cell efficiency due to the enhancement of TT when they work as front contact in silicon thin film solar cells. (C) 2012 Elsevier B.V. All rights reserved.