Single crystal grain low-temperature polycrystalline thin-film transistors (LTPS-TFTs) fabricated on a glass substrate have been the key target for developing transparent electronics such as monolithic three-dimensional integrated circuits (3DICs) and glass sheet computers because of their ultrahigh-performance. This study proposes a simple method to pre-define single-crystal grains with hole-patterned polycrystalline silicon (poly-Si) thin film. The crystal growth and the temperature distribution were clarified by observing the characterization of a hole-patterned poly-Si thin film. The relationship between the temperature gradient, crystal growth, and void formation in the poly-Si thin film is discussed. The location of voids is controllable in the hole-patterned poly-Si thin film. These pre-defined single-crystal grains are promising to fabricate ultrahigh-performance LTPS-TFTs.