The Si removal property achieved by a localized microwave hydrogen plasma was investigated. relationship between generation parameters (input power, H2 gas flow rate, and initial surface roughness) the (etching rate revealed. Stress relief of affected layer etching were also demonstrated. Moreover, this technique presents no etching-rate dependence on crystal plane orientation. Therefore, even ...

When constructing subway tunnels in coastal cities, boulders with high strength and large volume are often encountered. A number of engineering practices have shown that the existence will destroy unity homogeneity stratum. If tunnel is not properly handled during crossing construction, it lead to collapse surrounding rock; serious cases, may induce ground collapse, damage buildings, endanger s...