JPH04286971A - Data inspection device - Google Patents

Abstract

PURPOSE:To obtain a positive inspection data in a short time by converting an inspection data for collating data to a data with a low accuracy and then collating it, inspecting it, and then repeating inspection only to a portion which is found to be defective. CONSTITUTION:A data at a portion for storing inspection data for data verification 1 is converted to a data with a lower accuracy by a data conversion circuit 8 and then the output data is applied to a first collating circuit 5. On the other hand, an inspection data is obtained at a product inspection portion 7 and is applied to the circuit 5. A low-accuracy inspection is performed at the inspection portion 7, both data are compared by the circuit 5, and then a defective data is stored at a storage portion 9 if there are defective products. A corresponding original data is extracted from the storage portion 1 by a data extraction portion 10 based on this data and the inspection is performed only for a portion corresponding to it at a second inspection portion 11, thus obtaining a normal- accuracy data. The original data of the storage portion 1 and the inspection data of the inspection portion 11 are compared by a second comparison circuit 12, thus achieving collating in the case of a pseudo defect and non-verification in the case of a formal defect for obtaining an inspection result data efficiently.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a data inspection device for effectively inspecting inspection data for data verification in a short period of time. When inspecting the status of a device, high accuracy and high speed are naturally required. Normally, it is difficult to satisfy both at the same time, but when the entire device does not have to be inspected with the same accuracy, there is a desire to satisfy both at the same time. There was a desire to develop technology that could deal with such cases.

0002

2. Description of the Related Art When inspecting the status of a certain device and obtaining data in one data format, only a single precision is set according to that data format. For example, as shown in FIG. 4, a reticle used in the process of manufacturing a semiconductor integrated circuit will be described. In FIG. 4, 1 is an inspection data storage unit for data comparison, 2 is a reticle, 3 is a light emitting unit, and 4
5 indicates a light receiving section, 5 indicates a verification circuit, and 6 indicates a test result data storage section. When designing a semiconductor integrated circuit using a CAD system, inspection data and exposure data regarding a reticle can be extracted based on basic design data. Inspection data storage section 1 for data comparison stores inspection data regarding the reticle. On the other hand, a reticle manufactured based on the exposure data for the reticle is inspected by light from one end to the other as shown in FIG. Then, the sequential data obtained from the light receiving section 4 is compared with the data comparison inspection data 1 in the comparison circuit 5. When the reticle 2 is manufactured normally, result data indicating that all the verification results of the verification circuit 5 are normal is also stored in the storage section 6.

[0003] Generally, the peripheral portion of the reticle is a plain plate-like portion, and does not require greater precision in size than the aperture portion in the central portion. However, in the conventional case, as shown in FIG. 4, both the central part and the peripheral part of the reticle 2 were inspected in exactly the same manner.

0004

Problems to be Solved by the Invention In order to improve the inspection accuracy of the parts of the device that should be thoroughly inspected, it is necessary to use highly accurate inspection equipment as hardware. However, with the same device, inspections were performed with the same high precision even in locations that did not require thorough inspection. As a result, although the test was highly accurate, it took a long time. Note that if dust adheres to a device, it must be determined that there is a defect if it is a location that requires high-precision inspection, but it is sufficient to determine that the same dust is a pseudo-defect in the surrounding area. . If a defect exists only in the peripheral part, it should be determined that the product is defective, but if the defect is determined in the same way as the central part, the product is determined to be defective.

The object of the present invention is to improve the above-mentioned drawbacks, and to provide an inspection system in which locations that require high precision inspection are inspected in that manner, and locations that do not necessarily require high precision are inspected with low precision. The goal is to provide equipment.

[0006]

[Means for Solving the Problems] FIG. 1 is a diagram showing the basic configuration of the present invention. In FIG. 1, 1 is inspection data for data matching, 5 is a first matching circuit, 7 is a product inspection section, 8 is a data conversion circuit, 9 is a matching result data storage section, 10 is a data extraction circuit, and 11 is a second inspection circuit. 12 indicates a second verification circuit. The present invention has the following configuration in a data inspection device that inspects inspection data 1 for data comparison by a comparison circuit 5 that compares data obtained by inspecting a product. That is, a data conversion circuit 8 converts the data verification test data 1 into less accurate data and applies it to the first verification circuit 5;
A data extraction circuit 10 that extracts new inspection data for data comparison by the comparison circuit 5, a second inspection section 11 that inspects the product at a location corresponding to data 9, and inspection data 1 and second inspection section for data comparison. and a second collation circuit that collates the test data of No. 11.

[0007]

[Operation] In FIG. 1, the structure above the one-dot chain line is the same as that of the conventional inspection apparatus, and therefore its basic operation is the same. The data in the test data storage section 1 for data matching is converted into data with lower accuracy in the data conversion circuit 8. The output data of the data conversion circuit 8 is applied to the first matching circuit 5. On the other hand, the product inspection section 7 obtains inspection data and applies it to the first verification circuit 5. At this time, the product inspection section 7 performs an inspection with low accuracy. The first matching circuit 5 matches both data, and if there is a defect in the product, the defect data is stored in the storage section 9. Next, based on the data in the storage section 9, the data extraction section 10 extracts the corresponding original data from the data matching test data storage section 1. Then, the second inspection section 11 inspects only the locations corresponding to the data in the storage section 9, and obtains data with normal accuracy regarding the defective locations, so to speak. Next, in the second verification circuit, the original data in the data verification test data storage section 1 and the test data in the second test section 11 are verified. As a result, if it is a pseudo defect, it can be matched, but if it is a formal defect, it cannot be matched, and inspection result data can be effectively obtained.

[0008]

Embodiment FIG. 2 is a diagram illustrating a case where a 1-bit shift circuit is used as the data conversion circuit 8 and a reticle data inspection device similar to the conventional one is used in the product inspection section 7 as an embodiment of the present invention. In FIG. 2, 1 is an inspection data storage section for data comparison, 2 is a reticle, 3 is a light emitting section, 5 is a first comparison circuit, 7 is an overall product inspection section, and 9 is a storage section for comparison result data. , 13 is a 1-bit shift circuit as a data conversion circuit, 14 is a light receiving unit that obtains data with low precision,
Reference numeral 15 denotes a light receiving section that obtains data with normal precision, and is not used in FIG.

[0009] In FIG. 2, it is assumed that the data example shown in Table 1 is stored in the storage unit 1 for data verification test data. X, Y, H, and W shown as an address respectively indicate the X coordinate, Y coordinate, height data, and width data of a certain range of data of the reticle. Also, consider the decimal point between the 3rd and 4th digits counting from the LSB. The 1-bit shift circuit 3 removes 1 bit of the LSB from the data example in the test data storage section 1 and converts it into the data example shown in Table 2. As a result, the original test data is applied to the first verification circuit 5 with an accuracy of 1/8. Data with low accuracy is applied from the light receiving section 14 in the product inspection section 7 to the first verification circuit 5, and is verified against the applied data. As a result of matching,
Since matching/mismatching is determined, for the mismatched data, position data indicating the number of the data from the beginning in the inspection data 1 for data matching and defect data are stored in the matching result data storage section 9. .

0010

[Table 1]

[0011]

[Table 2]

Next, FIG. 3 is a diagram showing a specific example of the second inspection section and its vicinity, and is combined with FIG. 2 to form a data inspection device. In FIG. 3, 2, 3, 14, and 15 are the same as those in FIG. Reference numeral 11 shows the second inspection section as a whole, and in the case of FIG. 3, only the output data from the light receiving section 15 with normal accuracy is obtained. Reference numeral 12 indicates a second collation circuit, 16 a control unit for a stage that holds a reticle, 17 a storage unit for data required to be inspected, and 18 a data storage unit for final results.

In FIG. 3, the stage control section 16 knows the position of defect data from the data stored in the verification result data storage section 9, and controls the position of the stage so that the reticle 2 is inspected. In FIG. 3, the light receiving unit 15 is of normal precision, but since the target position of the reticle to receive light is small compared to that in FIG. 2, the total amount of data applied to the second matching circuit 12 is also Less than. The data extraction circuit 10 extracts original inspection data for data verification corresponding to the defect data from the data storage section 1 based on the data in the verification result data storage section 9 . The data is stored in the data storage section 17 as required and then applied to the second matching circuit 12. Since the second matching circuit 12 matches the mismatched data in the case of FIG. 2, it is only necessary to match a small amount of data with normal accuracy. Therefore, matching results can be obtained quickly and with normal accuracy.

[0014] The above description has been made regarding the case of a reticle as the inspection data, but the present invention can be applied not only to reticle inspection data but also to general data.

[0015]

As described above, according to the present invention, instead of inspecting all data with high accuracy, a low-accuracy inspection is first performed, and only the data determined to be defective is subjected to a normal inspection again. Therefore, reliable inspection data can be obtained in a short time. The higher the accuracy of the inspection mode, the more accurate data can be obtained, and the fewer places need to be inspected with high precision. In addition, unnecessary high-precision inspection is not performed, and since inspection is performed with varying precision, false defects are less likely to be picked up.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing the principle configuration of the present invention.

FIG. 2 is a diagram showing a part of the configuration of an embodiment of the present invention.

FIG. 3 is a diagram showing other parts of the configuration of the embodiment of the present invention.

FIG. 4 is a diagram illustrating a conventional data inspection device.

[Explanation of symbols]

1 Inspection data/storage section for data comparison 5 First comparison circuit 7 Product inspection section 8 Data conversion circuit 9 Verification result data/storage section 10 Data extraction circuit 11 Second inspection section 12 Second comparison circuit

Claims (1)

[Claims] Claim 1: A data inspection device that inspects data comparison inspection data (1) with a comparison circuit (5) that compares data obtained by inspecting a product, wherein the data comparison inspection data (1) is compared with data obtained by inspecting a product. Desired data is extracted from the data verification test data (1) by a data conversion circuit (8) that converts it into data and applies it to the verification circuit, and data (9) after verification by the verification circuit (5). a data extraction circuit (10) that extracts and obtains new inspection data for data comparison; a second inspection section (11) that inspects the product at locations corresponding to the data (9);
Inspection data for data comparison (1) and second inspection part (11)
A data inspection device comprising: a second collation circuit (12) that collates the inspection data of the data.