1. Field of the Invention
The present invention generally relates to a method or associated apparatus for performing defect analysis in a semiconductor wafer processing system. More particularly, the invention relates to a database that stores images and other information relating to defects on semiconductor wafers.
2. Description of the Related Art
Semiconductor wafers are prone to defects that occur during processing. Defects may occur at any stage of the processing of the wafers as integrated circuits are formed thereupon. Generally each fabricator of integrated circuits maintains a database of the causes of defects that occur on a regular basis. If the defect occurs frequently and a solution is apparent, the database may contain a description of the defect, the defect""s cause, and the solution to the defect. For example, certain defects may occur when a particular chamber becomes dirty. When these defects occur, the database would indicate the solution to be to execute a cleaning cycle for the particular chamber.
The various integrated circuit fabricators develop their own proprietary databases of defect information. As such, substantial funds are expended to produce the databases that include a complete listing of possible defects and solutions over time.
Therefore, there is a need in the art for a method for pooling the confidential defect information of multiple integrated circuit fabricators. This defect information could be accessed by various fabricators in a manner that would not reveal any confidential processing information. The combined defect information could be organized so that the analysis of the source or cause of a wafer defect can be correlated with the proper solution to the defect.
The present invention is a method and apparatus for creating a database comprising images and other semiconductor wafer defect information. The database is stored in a server having a plurality of clients connected thereto. The images and other information are supplied to the database from the clients. The clients collect the information and images from local metrology cells, then transmit the information and images via a network to the server. The information and images are organized in the database with associated causes and solutions for the defects to form a case study for each defect. The defect case studies may be pooled from a plurality of clients to form a comprehensive defect knowledge library. Any of the clients, if authorized, may remotely access the database to find the cause and solution for specific defects.