A device for trapping nano-particles formed in processing plasmas for reduction of nano-waste

Removal of nano-particles is important from the viewpoint that nano-materials may be hazardous to health when they deposit within the respiratory system. We have developed a method for measuring a sticking probability of nano-particles to a wall. The probability of nano-particles above 2 nm in size to a stainless-steel wall is close to 100% at a low ambient pressure below about 160 Pa. Based on this result, we have developed a device for trapping nano-particles formed in low pressure processing plasmas in order to reduce nano-waste, that is, waste of nm in size. The device traps nano-particles by collision and attachment of nano-particles to its surface. The trapping efficiency of the device for nano-particles above 2 nm in size is more than 99.8% at a low ambient pressure below about 160 Pa.