A METHOD AND APPARATUS FOR FORMING A UNIFORM FILM LAYER ON A DISK SURFACE

• Main Authors: ZHANG, JUN, JI, RONG, LIEW, YUN FOOK, TAY, TIAM HOCK
• Format: Patent
• Language: English
• Published: 28.04.2008

A METHOD AND APPARATUS FOR FORMING A UNIFORM FILM LAYER ON A DISK SURFACE An apparatus for forming a uniform film layer on a disk surface by applying a coating liquid disposed in a container to the disk surface, wherein exposure of the disk surface to the coating liquid is adapted to form a film layer on the disk surface, wherein the apparatus includes: a means of determining a position of a first region of the disk surface having a film thickness which is non-uniform with a film thickness of a second region of the disk surface, the film thickness of the first region being formed as a result of exposure of the first region to a surface wave of the coating liquid during movement of the disk surface relatively with the coating liquid disposed in the container; and a means automatically adjusting a withdrawal speed of the disk surface when a liquid level of the coating liquid is detected as being in proximity to the first region of the disk surface during withdrawal of the disk surface from the coating liquid, whereby the adjustment of the speed of withdrawal of the disk surface from the coating liquid results in the film thickness of the first region of the disk surface becoming substantially uniform with the film thickness of the second region of the disk surface.