Method of producing a substrate for an information recording medium and method of producing an information recording medium

摘要

In a method of producing a substrate for an information recording medium, the method including a washing/drying step of washing and drying said substrate subjected to precision polishing, a correlation is preliminarily obtained between a contact angle of water on a surface of the substrate before the washing/drying step and a size (height) of protrusions attached to the surface of the substrate during the washing/drying step. The contact angle of water on the surface of the substrate before the washing/drying step is controlled so that the protrusions have the size so as not to cause a hit when at least a recording layer is formed on the surface of the substrate to produce the information recording medium and when a slider provided with a recording device and/or a reproducing device is made to run on a surface of the information recording medium. The contact angle of water on the surface of the substrate before the washing/drying step may be controlled so that the protrusions have the size so as not to cause the hit and so as not to cause an error upon recording and/or reproducing the information recording medium which is produced by forming at least the recording layer on the surface of the substrate.