| 摘要 |
In etching chambers, as used, for example, in the semiconductor industry, deposits accumulate on the etching chamber wall. Due to the fact that these deposits are non-uniform, field strength peaks occurring at the tips of deposits can lead to sparkovers, which detach particles from the etching chamber wall and enable them to accumulate on a wafer that is to be processed. This can lead to functional failures of affected integrated switching circuits. The prior art prophylactic cleaning of the etching chamber is not suited for the actual degree of contamination of the etching chamber wall thus increasing method costs. The invention provides a monitoring device for an etching chamber comprising an etching chamber wall and at least one electrode, which is equipped with at least one signal tap on the etching chamber wall and one signal tap on the at least one electrode, with a conversion unit for converting the tapped signals into a form suited for evaluation, and with an evaluation unit which serves to identify patterns in the temporal progression of the signals and for deciding whether it is necessary to clean and/or service the etching chamber. The device enables the inventive method to be carried out. Said method comprises the following steps: A. tapping an electric signal between the etching chamber wall and at least one electrode of the etching chamber; B. measuring a temporal progression of the electric signal; C. identifying patterns in the temporal progression of the electric signal which deviate from the normal patterns in a flawless etching chamber, and; D. making a decision, which is based on the identified pattern in the temporal progression of the signal, whether it is necessary to service and/or clean the etching chamber.
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