摘要 |
In a method of forming a video disc or a digital sound recording disc for example, a uniform layer of a predetermined thickness has to be applied to a substrate, and according to the invention, the layer material is applied in the form of a liquid with a known viscosity and the disc is rotated at a first velocity to spread the liquid and then the disc is rotated at a higher velocity to dry the liquid at least partly, to be in the form of a coating having a thickness which is dependent upon the viscosity of the liquid and the higher velocity at which the substrate is rotated. The method may be used is preparing a glass or other substrate for the application of a photoresist layer, or it may be used in the application of the photoresist layer, or in the application of a developer for developing an exposed photoresist layer. |