Abstract: An automatic supervision system using an ion beam map generated by an ion implantation machine during an ion implantation process a feature extraction circuit and a data converter. The feature extraction circuit receives a beam current signal and a display blanking signal from the ion implantation machine, and extract features of the ion beam map. The data converter is coupled to the feature extraction circuit and converts the features into indexes indicative of the alignment and symmetry of beam maps. The data converter also compares the indexes to index values or symptoms of known abnormal ion beam scanning, which allows the data converter to recognize abnormal ion beam scanning and indicate the proper corrective action to adjust the ion beam scanning. Thus, the two-dimensional beam map recognition analysis is reduced to a one-dimensional feature analysis, thereby simplifying the beam map recognition process.

Abstract: An intelligent supervision system on the ion beam map during ion implantation process includes an ion implanter for introducing ions into a wafer, a feature extractor for receiving a beam current signal and a display blanking signal from the ion implanter to extract features of the beam current signal; a fuzzification subsystem for justifying confidence level on the features; and an expert system for recognizing symptoms of abnormal scanning and providing an indication thereof to a human operator. The expert system also provides an indication of appropriate corrective action, which an operator then uses to adjust the implantation process. Alternatively, the expert system may be configured to provide control signals directly to the ion implanter to adjust the implantation process without the need for an operator.