JP2005331425A - Defective device analysis method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To acquire data with high analysis density for every defective category with large compaction of failure analysis time by classifying non-defective goods and defective goods in a same storage box. <P>SOLUTION: An automatic test device is equipped with a tray 20 for mounting devices to be tested, the devices in the tray 20 are tested with a plurality of items, and after the tests the devices are restored to the tray 20. When the defects are generated in the automatic test equipment, the defective devices are classified in the tray 20 for every defective item. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  According to the present invention, a defect is classified so that a defective device can be mounted on a tray on which a device (electronic component) such as an IC for testing is mounted so that the defective device can be easily mounted. The present invention relates to a device analysis method.

(1): Description of Conventional Automatic Test Apparatus (Handler) FIG. 3 is an explanatory view of a conventional automatic test apparatus (automatic machine). In FIG. 3, the automatic test apparatus includes an untested part 1, a test part 2, a socket part 3, a defective box 4, and a tested part 5.

  The untested portion 1 is a place where a tray on which an untested device that has not been tested is mounted is stored. The test unit 2 is a place where a tray loaded with a device to be tested is placed. The socket part 3 is a place where a socket for connecting to a device and performing a test is provided. The defective box 4 is a box that stores defective products as a result of device testing. The tested part 5 is a place for storing a tray on which non-defective products are mounted as a result of the device test.

(2): Description of Conventional Tray FIG. 4 is an explanatory diagram of a conventional tray. In FIG. 4, ICs as devices can be loaded from NO.1 to NO.100 (100 ICs) on the tray. Further, the storage units of the untested part 1 and the tested part 5 can store up to 10 trays. Therefore, the maximum number of ICs that can be tested at one time is 1000.

(3): Description of Operation of Conventional Automatic Machine (Handler) Hereinafter, the operation of the conventional automatic machine will be described with reference to FIGS.
(1) The automatic machine transports a tray with 100 ICs (with 100 ICs) from untested part 1 to test part 2.

  (2) The automatic machine moves only one IC from the tray in the test unit 2 to the socket unit 3 by hand.

  (3) The automatic machine performs an IC test at the socket part 3. If it is a non-defective product, the IC is returned to the original position of the tray in the test part 2 by hand, and if it is defective, the IC is put into the defective box 4 by hand. Put in.

  (4) The automatic machine repeats steps (2) to (3) until all the ICs mounted on the tray in the test section 2 have tested.

  (5) The automatic machine transports the tray to the tested part 5 when all the ICs mounted on the tray in the testing part 2 have been tested.

  In this way, the ICs mounted on the tray are tested in order from NO.1 to NO.100. After all the tests were completed, the engineer took out the IC contained in the defective box 4 and set it in the socket 3, and then acquired a FAIL (defective) data log or the like to perform a failure analysis.

(4): Explanation of classification of defective IC chip Conventionally, when a device is measured and a defect occurs, there is a defective device classification storing mechanism that automatically stores the defective device in the corresponding defective classification portion of the defective box. (See Patent Document 1).
Japanese Utility Model Publication No. 5-94780

  When performing the IC (memory etc.) test with the conventional automatic machine, there are the following problems.

  (1): When a defect occurs, it is put in a defect box, and after all the tests are completed, the automatic machine is stopped, and then the engineer performs manual defect analysis one by one. It took time. In addition, a specialized engineer who performs defect analysis is necessary.

  (2): The classification storage mechanism that stores a defective device in a corresponding defective classification portion of a defective box does not classify a good product and a defective product in the same storage box.

  The present invention solves the above-mentioned conventional problems, classifies non-defective products and defective products in the same storage box, and greatly shortens the failure analysis time and acquires data with high analysis density for each failure category. With the goal.

  FIG. 2 is an explanatory diagram of the tray of the present invention. In FIG. 2, 20 is a tray, 21 is a non-defective product storage site, 22 is a defective product storage site, 23 is a high-temperature defective storage site, and 24 is a low-temperature defective storage site.

  The present invention is configured as follows to solve the above problems.

  (1): The automatic test apparatus includes a tray 20 on which a device for performing a test is mounted, and an automatic test apparatus that tests a plurality of items of the devices in the tray 20 and returns to the same tray 20 after the test. When a defect occurs in the test, a device is classified in the tray 20 for each defective item. For this reason, it is possible to classify non-defective products and defective products using a tray that is the same storage box, and it is possible to greatly reduce the failure analysis time and obtain data with high analysis density for each failure category.

  (2): In the defective device analysis method of (1), a detailed test for failure analysis is performed when a failure occurs in the test by the automatic test apparatus. For this reason, detailed data for performing failure analysis can be automatically acquired.

  The present invention has the following effects.

  (1): Since a device is classified in the tray for each defective item when a defect occurs in a test with an automatic test equipment, it is possible to classify a non-defective product and a defective product in a tray that is the same storage box, and analyze the failure. Data with high analysis density can be acquired for each time category with a significant reduction in time.

  (2): Since a detailed test for failure analysis is performed when a failure occurs in a test using an automatic test apparatus, detailed data for performing failure analysis can be automatically acquired.

(1): Explanation of automatic machine (handler) The automatic test apparatus (automatic machine) of the present invention has the same configuration as the conventional apparatus (FIG. 3) (however, the defective box 4 is not required). Are provided with an untested part 1, a test part 2, a socket part 3, and a tested part 5.

  FIG. 1 is an explanatory diagram of the main part of the automatic test apparatus of the present invention. In FIG. 1, main parts of an automatic test apparatus that performs an automatic test of a memory that is an IC (integrated circuit) include a socket part 3, a tray part 11, a handler control part 12, a handler hand part 13, a socket presser plate part 14, A memory tester control unit 15, a memory tester driver unit 16, and a memory tester comparator unit 17 are provided.

  The socket section 3 is a place where a socket for performing a test by connecting to an IC (here, a memory) that is a device for performing the test is provided. The tray unit 11 is a place (test unit 2) where a tray 20 on which an IC to be tested is mounted is placed. The handler control unit 12 controls the handler hand unit 13. The handler hand unit 13 moves the IC of the tray unit 11 to the socket unit 3 by hand under the control of the handler control unit 12, and returns a normal (non-defective) IC for which testing has been completed to the tray unit 11 by hand. The socket pressing plate portion 14 is for electrically connecting an IC for testing by moving the socket pressing plate up and down. The memory tester control unit 15 controls the memory tester. The memory tester driver unit 16 drives the memory in order to test the memory that is an IC under the control of the memory tester control unit 15. The memory tester comparator unit 17 compares the result of the memory (IC) test with a set value and determines whether it is a defective product or a non-defective product.

(2): Explanation of tray FIG. 2 is an explanatory view of the tray of the present invention. In FIG. 2, the tray 20 is provided with an IC mounting portion 21 (a non-defective product place after the test) and an inferior product place 22 at the bottom (the upper half is placed on the IC). In the case of the mounting part 21, the lower half is an empty area before the test). The upper IC mounting part 21 becomes a non-defective place after the test. The defective product storage 22 is provided with a high temperature defective storage 23 and a low temperature defective storage 24. The high temperature defect storage 23 is provided with high temperature and category 1 (CAT1H) to high temperature and category 3 (CAT3H). The low temperature defective storage 24 is provided with a low temperature category 1 (CAT1L) to a low temperature category 3 (CAT3L). In each category, up to three defective products can be placed (for example, there are three IC locations CAT11H to CAT13H in high temperature and category 1).

  In this way, if a tray (for example, divided into categories for each functional test) is viewed, non-defective products, high-temperature defective products, low-temperature defective products, defective categories, and the like can be easily understood. In addition, by color-coding the tray for each non-defective product, high-temperature defective product, and low-temperature defective product place (for each category), the state after the IC test can be understood at a glance. In addition, the number of categories and the number of defective product storage areas can be increased or decreased appropriately (depending on the expected defect rate, etc.). Furthermore, since a part of the tray (half in this example) is used as a defective item storage place, it can be handled without changing the size of the conventional tray.

(3): Description of Operation of Automatic Machine Hereinafter, the operation of the automatic machine will be described with reference to FIGS.

  (1) The automatic machine conveys the tray on which the IC is mounted from the untested part 1 to the test part 2.

  (2) The automatic machine moves only one IC from the tray in the test unit 2 to the socket unit 3 by hand.

  (3) The automatic machine performs an IC test at the socket part 3. If it is a non-defective product, the IC is returned to the original position of the tray in the test part 2 by a hand. (In the case of a high-temperature test, it is put into a high-temperature defective place 23, and in the case of a low-temperature test, it is put into a low-temperature defective place 24, respectively, into defective categories).

  (4) The automatic machine repeats steps (2) to (3) until all the ICs mounted on the tray in the test section 2 have tested.

  (5) When all the ICs mounted on the tray in the test section 2 have completed the test (high temperature and low temperature tests), the automatic machine will perform further detailed failure analysis as necessary.

(4): Detailed explanation of defect analysis The lower part of the tray is used as a defect place. The defective place is classified into high temperature and low temperature defects, and further classified for each defect test item (category classification). As described above, the defect analysis is performed as described above, but in order to perform a more detailed analysis, a test program for defect analysis is used.

  As an example, a case of failure analysis of a high-temperature category 1 (CAT11H) sample will be described.

  (1) When the test of the IC mounted on the tray of the test section is completed, the defective sample in the CAT 11H of the high temperature defective place is moved to the socket section 3.

  (2) Blow hot air to the IC.

  (3) Call a test program for failure analysis of high temperature and category 1 (CAT1H) (eg, access time test when the power supply voltage is changed).

  (4) Obtain defect analysis data and save it.

  (5) From the socket part 3, place the IC in the original defective place (CAT11H).

  (6) If there is another defective sample of CAT1H, repeat the above items (1) to (5).

  In this way, it is possible to automatically perform all the detailed defect analysis other than the device test of the sample in the defective place.

  As described above, according to the present invention, since defective devices are placed for each category, for example, when analyzing a sample of category 1 of high-temperature defects, specialization of defects (low temperature or the like that seems unnecessary) By omitting the analysis of other categories) and performing failure analysis automatically, the time required for failure analysis is greatly reduced (essentially, engineers do not need to perform analysis work). Data with high analysis density can be acquired.

  In the example described above, the detailed analysis is performed by moving from the defective place of the tray to the socket unit 3 and calling the test program for defect analysis. However, when the socket unit 3 first determines that the product is defective ( It is also possible to call up a test program for failure analysis (without returning to the defective storage area of the tray) for detailed analysis.

It is explanatory drawing of the principal part of the automatic test apparatus of this invention. It is explanatory drawing of the tray of this invention. It is explanatory drawing of the conventional automatic test apparatus. It is explanatory drawing of the conventional tray.

Explanation of symbols

20 Tray 21 Good product place 22 Defective product place 23 High temperature defective place 24 Low temperature defective place

Claims (2)

A tray with devices for testing,
An automatic test apparatus that performs a plurality of tests on devices in the tray and returns the same tray after the test,
A defective device analysis method comprising: classifying devices in the tray for each defective item when a defect occurs in a test by the automatic test apparatus.   2. The defective device analysis method according to claim 1, wherein a detailed test for failure analysis is performed when a failure occurs in the test by the automatic test apparatus.

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