Mitsubishi Denki Kabushiki Kaisha

Ryoden Semiconductor System Engineering Corporation

Masaaki Furuta

Toshikazu Tsutsui

Tohru Koyama

Yasukazu Mukogawa

Fumihito Ohta

Yohji Mashiko

A method comprises steps of: forming a FBM (step S1); generating a second failure map by compressing data of the FBM (step S2); recognizing a failure mode from the second failure map (step S3); selecting a specific failure mode (step S4); and analyzing the specific failure mode by using a part of the corresponding FBM (step S5). This makes a detail analysis possible while suppressing the number of processing data, and thereby achieves a failure analysis method and device improving accuracy and reliability in comparison result.

Failure analysis method and device

Data containing defect position coordinates obtained based on the result of physical inspection of foreign material, a defect or the like at the surface of a semiconductor wafer by a defect inspecting apparatus is stored. Also stored is data of physical coordinates obtained based on fail bit data from a tester. Data indicating an additional failure region is produced by an additional failure region estimating apparatus based on the fail bit data, and is stored. Collation produces data of corrected physical position coordinates by adding the stored data of limitation by failure mode to the stored data of physical position coordinates, and collates the data of corrected physical position coordinates with stored data of defect position coordinates. Accordingly, accuracy in collation is improved, and failure can be analyzed even if caused not by a defect located at an address of the failure obtained by the fail bit data but by a defect relating to the defect located at the address of a failure.

System for analyzing a failure in a semiconductor wafer by calculating

Failures detected by a tester are collated with defects detected by a defect checking device (Step S6). The collation is performed by retrieving defects coincident with each failure within a tolerance R0. Based on a mean value of displacements between the failures and the defects which are coincident with each other, coordinate values of the defects are corrected (Step S10). The coordinate values are corrected only when a collating ratio S that is a ratio of failures with which defects are coincident to whole failures exceeds a constant value S0 (Step S7). As a result, a coordinate value of a defect having high precision is obtained.

Failure analyzer

Data containing defect position coordinates obtained based on the result of physical inspection of a foreign material, a defect and the like at a surface of a semiconductor wafer by a defect inspecting apparatus is stored in storage means. Data of physical position coordinates obtained based on fail bit data from a tester is stored in storage means. Data indicating an additional failure region is produced by additional failure region estimating means based on the fail bit data, and is stored in storage means. Collating means produces data of corrected physical position coordinates by adding the data of limitation by failure mode stored in storage means to the data of physical position coordinates stored in storage means, and collates the data of corrected physical position coordinates with data of defect position coordinates stored in storage means. Accordingly, accuracy in collation is improved, and therefore, a failure can be analyzed even if the failure is not caused by a defect located at an address of the failure obtained by the fail bit data but by a defect relating to the defect located at the address of a failure. As a result, accuracy in estimation is improved.

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Hyogo, Japan

Masaaki Furuta