Patent ID: 7219676
Filing Date: 2007-05-22
Classification: B08B,G01N,H01L,Y10S

Abstract:
1. A combination of a process vessel having a bottom wall and a sidewall and defining a process space therein dedicated for use in accommodating substrates during their processing, a substrate guide disposed at the bottom of said process vessel and configured to support at least one substrate upright within the process vessel as oriented vertically within the vessel as spaced above the bottom wall of the process vessel, and a substrate detecting apparatus, wherein the substrate detecting apparatus comprises: a first sensing unit having first sensor elements disposed on the sidewall of said process vessel, the first sensor elements being oriented and cooperative to detect for the presence of substrates that are supported upright by said substrate guide; and a second sensing unit having second sensor elements disposed on the sidewall and on the bottom wall of said process vessel, said second sensor elements being oriented and cooperative to detect for the presence of objects lying on the bottom wall of said process vessel, whereby substrates or remnants thereof which have fallen from the substrate guide and have come to rest on the bottom wall of the process vessel can be detected.