Comparison of positive lithography and negative lithography 1) Bottom film formed by gas phase After the silicon wafer is cleaned and baked, the base filmJoint shaft harmonic motor FHA-25C-160-E250-C is formed by dipping, spraying or chemical vapor deposition (CVD). The base film makes the surface of the silicon wafer separate from water molecules and enhances the photoresist Binding force. The nature of the base film Joint shaft harmonic motor FHA-25C-160-E250-Cis to act as a connecting agent between silicon wafers and photoresist, and is chemically compatible with these materials. 2) Spin coating Spin coating steps After the base film is formed, the surface of the silicon wafer should Joint shaft harmonic motor FHA-25C-160-E250-Cbe evenly covered with photoresist. At this time, the silicon wafer is placed on the vacuum chuck, and the bottom of the chuck is connected to the rotating motor.