Patent ID: 6203625
Filing Date: 2001-03-20
Classification: B08B,H01L

Abstract:
A method of cleaning a semiconductor wafer covered with silicon oxide, topped with an aluminum layer in which patterns are formed by plasma etching of the aluminum, said etching causing the formation of a polymer on the substantially vertical walls of the patterns, including rotating the wafer in its plane around its axis, in an enclosure under a controlled atmosphere, at ambient temperature, including the following steps:rotating the wafer at a speed between 500 and 2000 rpm in an enclosure filled with nitrogen;sprinkling the wafer with water in a liquid state directed substantially at the center of the wafer while performing the rotating step;introducing gaseous hydrofluoric acid during a pre-determined cleaning time, while maintaining the sprinkling and the rotating; andrinsing the wafer by continuing the sprinkling to remove hydrofluoric acid from the wafer, after the pre-determined cleaning time.