Liquid Chemical Identification by an on-line suitable parameter measurement
Publication Date: 2003-Jul-25
The IP.com Prior Art Database
Liquid chemical identification by an on-line suitable parameter measurement
Problem to be solved : to identify with success a chemical : - during the connection of a new mobile tank to a chemical distribution system
- all over the distribution system
Background : The semiconductor industry uses many chemicals for silicon wafer processes. Liquid chemicals are distributed from chemical distribution systems. Each system is dedicated
to a chemical, to a grade or to a concentration. During a chemical distribution system refilling, the operator has to be sure to connect the right mobile drum to the right system. Identification mistakes could have serious consequences such as : reaction between chemicals (e.g. acid and base), line contamination... The result is always an interruption of the chemical distribution and
sometime a part of the distribution components have to be replaced. Some devices exist to reduce the risk of fault during connection : key-coded dispense heads are used to avoid chemical mixing, identification system using color codes or bar codes. Nevertheless, these systems are not perfect. Some of them could be forced or generate some defaults.
Due to complex networks and interconnection piping, the composition of a chemical could changed through the distribution : unlikable or drifted concentration, unexpected dilution, solid sedimentation...
The chemical identification close the point of use gives an additional information about the chemical qua...