IC testing method and IC testing device using the same

Abstract

In an IC testing apparatus which executes a function test and a d.c. test, a resistor having a high resistance is connected to the output side of a d.c. tester such that the connection of the resistor allows a function test to operate normally if the d.c. tester is left connected to the function tester, thus allowing the d.c. test to be interrupted into the execution of the function test to enable a concurrent execution of the function test and the d.c. test, whereby a control which takes time such as changing switches in the d.c. tester is executed during the function test, thus preventing the changing time interval of the switches from being added to a time interval required for the test to thereby reduce the testing time interval.

Description

[0001] 1. Technical Field[0002] The present invention relates to an IC testing method which enables a function test and a leak test for entries of a d.c. test to be performed in a brief time interval when conducting a function test and a d.c. test for a semiconductor device such as a memory formed by a semiconductor integrated circuit, and to an IC testing apparatus which employs the method.[0003] 2. Background Art[0004] Heretofore, an IC testing apparatus which tests a semiconductor device such as a memory performs a function test which determines whether or not the function of the semiconductor device is normally operating and a d.c. test which determines whether or not respective terminals of the semiconductor device exhibit predetermined d.c. characteristics, and determines an IC which proved to be normal in the both tests to be an acceptable product.[0005] FIG. 3 shows a schematic arrangement of an IC testing apparatus. In this Figure, character TES designates the entire IC tes...

AI Technical Summary

Benefits of technology

[0030] The invention is characterized by an arrangement which allows the d.c. tester to be maintained connected to a terminal on an IC under test even during the function test, which is enabled by connecting d.c. tester to a terminal on the IC under test through a resistor, the sophistication being such that the connection of the resistor prevents the d.c. tester from presenting a significant load as viewed from the function tester.

[0031] With this arrangement, there is proposed an IC testing method which permits the d.c. test to be executed by controlling the output terminal of a driver of the function tester in a high impedance mode even during the function test, thus dispensing with the need for a switch control to disconnect the function tester during the time the d.c. test is being executed and thus allowing an execution of a leak test among a d.c. test item during the interval for the functions test.

[0032] Thus, with the IC testing method according to the invention, the leak test for a d.c. test item is completed at the same time with the end of the function test, thus eliminating the need for a special time interval to conduct the leak test. Consequently, there is obtained an advantage that the length of time required for the test can be significantly reduced.

[0041] As a consequence, if the d.c. test is executed during the execution of the function test, the d.c. test is dispersed in a compound form in the function test, and there is obtained an advantage that a length of time for the compounded test cannot be significantly longer than the length of time required for the inherent function test, thus allowing the function test and a leak test to be completed within a brief interval.

Problems solved by technology

Accordingly, if a switching control of the switches S.sub.11-S.sub.1n and the change-over switches S.sub.21-S.sub.2n is executed for every terminal, there results an inconvenience that the d.c. test requires an increased length of time.

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