Patent ID: 6784445
Filing Date: 2004-08-31
Classification: B24B,C23C,G01B,H01J,H01L

Abstract:
An apparatus for monitoring layer depositions in a process chamber, comprising:a light source; a disk-shaped sensor element subjectable to deposition and growth of a deposition layer; a light detector disposed outside the process chamber; said sensor element having a first surface on one side of said sensor element, a second surface on an opposite side of said sensor element, and a region extending from said first surface to said second surface, said region being configured for light to pass through and to absorb light to a significantly lesser extent than a remaining part of said sensor element, an intensity of the light being measured in dependence on said region being grown over by a thickness of the deposition layer, the intensity of the light from said light source being measured through a window formed in the process chamber.