表面活性化接合における炭素パーティクル排出量計測の自動化

抄録

Surface activated bonding is a technology used in semiconductor manufacturing. This technology enables wafers to be bonded directly at room temperature by irradiating them with a fast atom beam. The fast atom beam removes oxides and contaminants from the wafer, thereby activating the surface. A device that emits a fast atom beam is called a fast atom beam source, which generates the beam using plasma from a carbon electrode. However, after several hundred uses, carbon particles are emitted from the electrode surface. These carbon particles cause voids at the wafer bonding interface. In a previous study, a method for in-process quantitative evaluation of carbon particle emissions was proposed. However, hundreds of experiments and measurements were performed manually in the previous study, resulting in widely varying data accuracy. Therefore, in this study, we developed the methods used in previous study and automated all experiments and measurements. The operation of the fast atom beam source and the measurement of particles were automated using “LabVIEW” software. Particle measurement includes photography with a camera and image processing. By automating these processes, the frequency and reliability of measurement improved compared to previous methods. As a result, it was confirmed that particles begin to be emitted after approximately 400 uses, and then continue to be emitted at a constant rate. This behavior is consistent with what has been empirically recorded in mass production sites, confirming the effectiveness of this study.