Method of forming a thin film on the surface of a substrate using a roll coater

摘要

A method of forming a thin film on the surface of a substrate using a roll coater without forming a projection of the thin film near the rear edge of the substrate includes the steps of: loading a substrate on a stage, moving the stage in a predetermined direction up to a certain position where at least a portion of the surface of the substrate comes into contact with the applicator roll while controlling the operation of the roll coating apparatus so that the amount of coating fluid transferred per unit area from the applicator roll to the substrate surface is a predetermined value, and further moving the stage in the predetermined direction to cancel the contact between the surface of the substrate and the applicator roll while controlling the operation of the roll coating apparatus so that the amount of coating fluid transferred per unit area from the applicator roll to the substrate surface is relatively reduced. Until the stage reaches the certain position, a predetermined amount of coating liquid is supplied, and thereafter, a smaller amount of coating liquid is supplied to the surface of the substrate. For example, the transfer speed of the stage is increased while maintaining the rotation speed of the applicator roll at a constant level, or the rotating speed of the applicator roll is decreased while maintaining the transfer speed of the stage at a constant level.