Metallic nanoparticle implant while thermal processing has been widely reported and brilliantly applied in surface modification. However, arguments remain on the basics of etching mechanism in terms of the main drive force. In this work, nanohole (NH) formation is investigated on quartz by assistant of Cu nanoparticles. With confocal morphological and chemical characterizations by photo-induced force microscopy, the evidence of Cu-Si alloy formation is found thus strongly suggests the substrate decomposition can play an important role in NH fabrication. Based on the results obtained with temperature gradient, the two-regime evolution process is observed.