In this article, metal (palladium, Pd)-induced lateral crystallization (MILC) of amorphous-germanium (alpha-Ge) films prepared by room-temperature sputtering on an insulating material (SiO2) is observed and investigated using micro-Raman microscopy and transmission electron microscopy. The planar alpha-Ge thin films were annealed at 300, 350, and 400 degrees C in a N-2 ambient. The MILC phenomenon is not observed for the samples annealed at 300 degrees C for 2 h, while the MILC phenomenon is observed for alpha-Ge films annealed at 350 and 400 degrees C for 2 h with a lateral growth rate of similar to 1.1 and 1.3 mu m/h, respectively. A poly-Ge film with a 400 degrees C annealing temperature exhibits a smaller full width at half-maximum and a higher intensity of the sharp c-Ge peak than that annealed at 350 degrees C, which can be the promising material candidate for Si-based three-dimensional integrated circuit applications.