High-accuracy resist development process with wide margins by quick removal of reaction products

摘要

We have demonstrated that highly reliable resist patterning is achieved by effectively removing reaction products by means of ultrasonic development and the addition of surfactant to the developer. It has been found that the reaction products form a stagnant layer, resulting in preventing the resist-developer reaction. Thus, the existence of the stagnant layer leads to the fluctuation of the developing characteristics and the degradation of the resist contrast, resist sensitivity, and process margins. To quickly remove the stagnant layer from the resist-developer reaction interface, two techniques are employed: physical method of developing with ultrasonic agitation and chemical method of the addition of surfactant to developer. In addition, it has been found that the agitation of developer lowers the etch rate of (100) Si and prevents the appearance of pyramid-shaped etch pits on Si surface.