Abstract
Abstract Biomachining has provided a new vision of the property of micromachining. Presently, copper processing is the main stream in semiconductor industry. The main purpose of this research is the application of microorganism in micromachining of copper workpiece. Optical tweezers and microfluidic channel are used for manipulating microorganism. Thiobacillus ferrooxidans and thiobacillus thiooxidans have proved their potential for etching metal. In this study, two bacteria mentioned above are evaluated for material removal. There are three parts in this study, including the measurement of the tweezing efficiency, the investigation of the possible damage to thiobacillus thiooxidans under Nd：YAG laser and biomachining copper by microbers under optical tweezers. It is noted that thiobacillus thiooxidans and thiobacillus ferrooxidans were moved at and by optical tweezers with 450 mw of laser power. The activity of thiobacillus ferrooxidans has not been weakened at 900 mw of laser power lasting for 3 hours. The depth of the metal removal is measured. From the results of the experiment, thiobacillus thiooxidans show a machining depth of 80 nm in copper under the laser of tweezers. The accumulation of copper by thiobacillus ferrooxidans and the extracellular polymeric substances irradiated by Nd：YAG laser was firstly observed. The alphabet was successfully written on the copper sheet by their method in the study.