Study on controlling the adsorption state of particle on the polished silicon wafer

With the feature size of ULSI becoming smaller and smaller, the surface quality of the polished silicon wafer becomes more and more important. In this paper, the adsorption state of a particle on the polished silicon wafer and the preferential adsorption model are studied, on the basis of which the non-ion surfactant is chosen as the second kind of adsorbate, which is preferentially adsorbed onto the polished silicon wafer and is easily washed out. Experiment results show that the application of the surfactant makes the adsorbate keep in physical adsorption that is easy to wash out for 120 h, but it may be kept in physical adsorption for 2 h by using the common washing method. The method in this paper has many advantages such as lower cost, higher efficiency and easily operation and so on. What's more, it is also apt to produce large scale circuits.