JP2650974B2 - Inspection method for semiconductor integrated circuit - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an inspection method for inspecting static characteristics of a semiconductor integrated circuit and displaying a waveform of an inspection result.

2. Description of the Related Art FIG. 5 shows a process flow chart of a conventional semiconductor integrated circuit inspection method. In FIG. 5, the flow of the solid line arrow is an example of the procedure of the static characteristic inspection performed by the static characteristic tester, and the flow of the dotted arrow is the procedure for taking the waveform data of the inspection result into the waveform display device. After the inspection of one inspection item is completed, before the inspection condition is applied to the semiconductor integrated circuit to be measured before the inspection condition is applied to the next inspection item, the inspection result generated in the inspection of the immediately previous inspection item A process for capturing a waveform is performed, and subsequently, a process for preparing an inspection for the next inspection item n (a process for decoding inspection conditions for the inspection item n and a waveform reading preparation) is performed.

Problems to be Solved by the Invention However, in such a conventional method, a process shown by a dotted line in FIG. 5 is performed between the static characteristic inspection device and the waveform display device. It takes a long time between the inspection item and the inspection item, and the length of the required time depends on the complexity of the inspection content. The voltage of the semiconductor integrated circuit under test, to which voltage is applied even during the transition to the next inspection item, depends on the amount of time required, and the amount of heat generated depends on the length of the required time. However, there is a disadvantage that the characteristics after heat generation are displayed, but desired static characteristics cannot be displayed or the waveform display becomes unstable.

The present invention eliminates such inconveniences, and provides a semiconductor integrated circuit inspection method capable of reducing the time required for the inspection and stably displaying the inspection result waveform of the static characteristic of the semiconductor integrated circuit to be measured. The purpose is to:

Means for Solving the Problems In order to solve the above problems, a method for inspecting a semiconductor integrated circuit according to the present invention uses an item number for each inspection item sent from an inspector and the item number corresponding to the item number. A first step of storing inspection conditions and preparing for measurement, and applying the inspection conditions generated by the inspection device to the semiconductor integrated circuit while the item numbers corresponding to the inspection conditions are being stored;
A second step of comparing the item numbers stored in the step (a) with each other and selecting an output signal of the semiconductor integrated circuit corresponding to the matched item number; and measuring data obtained by A / D converting the selected output signal. A third step of storing a plurality of inspection items in association with the stored item numbers;
After performing the third step in parallel and completing all inspections,
A fourth step of performing a calling waveform display process by associating the stored inspection conditions and measurement data with the stored item numbers.

According to the present invention having the above configuration, the item number of each inspection item and the inspection condition corresponding to the inspection item are stored in the first step in advance, and subsequently, the inspection condition generated by the inspection device simultaneously,
Since the inspection result data is stored by associating the item numbers with the stored item numbers, after all the inspections are completed, the stored inspection conditions and the measurement data corresponding to the already-existing item numbers are called. In addition, inspection conditions and measurement data corresponding to inspection items can be displayed without confusion. Further, the step of decoding inspection conditions in advance for each inspection item, which has been conventionally performed, is eliminated, so that the time required for inspection can be reduced, and stable waveform observation can be performed.

Hereinafter, an embodiment of a method for testing a semiconductor integrated circuit according to the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram of an inspection apparatus according to this embodiment. In FIG. 1, reference numeral 9 denotes an inspection result waveform display device, 10 denotes a static characteristic inspection device, and 11 denotes a semiconductor integrated circuit to be measured. The static characteristic inspection apparatus 10 includes measuring instruments (1) to (n) individually connected to the respective terminals of the semiconductor integrated circuit to be measured, and a measuring instrument control circuit 7, and the measuring instrument control circuit 7. 7 by the control signal from the measuring device (1)
The necessary number of measuring devices up to (n) are selected, and the operation of applying a DC voltage or DC current to the semiconductor integrated circuit 11 to be measured and the operation of measuring the terminal voltage or terminal current are performed.

Next, the inspection result waveform display device 9 includes an inspection condition storage / comparison circuit 1, a switch 3 for selecting an output signal of each of the measuring devices (1) to (n), and an output signal of the inspection condition storage circuit 1. A control circuit 2 for controlling the selection operation of the switch 3 by an A / D converter 4 for A / D converting the signal selected by the switch 3; and a memory 5 for storing item numbers and digital data of test result waveforms. And a waveform display 6 for receiving the waveform data stored in the memory 5 and the test condition data of the test condition storage / comparison circuit 1 and displaying a waveform on a display surface.

This inspection device is a device for continuously inspecting a large number of identical products one by one while replacing them one by one. However, as a measurement preparation, a static characteristic test of a product to be incorporated into an inspection result waveform display device is performed in advance. Then, the inspection conditions for each inspection item are fetched from the static characteristic inspection device 10, and the decoded inspection conditions are written in the inspection condition storage / comparison circuit 1. Then, mass production inspection is started by replacing with a new semiconductor integrated circuit of the same type.

FIG. 2 is a diagram for explaining the function of the inspection result waveform display device 9. The data a (expressed in analog form) stored in the memory 5 and the inspection stored in the inspection condition storage / comparison circuit 1 are shown. Call condition b in association with the inspection item,
The waveform c is displayed on the display surface.

Next, the inspection method will be described with reference to the process flow charts of FIGS. First, as a measurement preparation operation, a process flow chart of FIG. 3 will be described. A bias (inspection condition) such as a necessary voltage or current is applied to each terminal of the semiconductor integrated circuit under test 11 under the control of the measurement device control circuit 7 in the static characteristic inspection device 10 to confirm that a predetermined characteristic can be measured. . At the same time, the measurement control circuit 7 sends the information of the inspection condition and the information of the item number of the corresponding inspection item to the inspection condition storage / comparison circuit 1 in the inspection result waveform display device 9 via the signal line 101. It is sent out and stored in the inspection condition storage / comparison circuit 1. In this operation, for each of the inspection items from inspection item 1 to inspection item n, the item numbers and the inspection conditions are stored in association with each other, and the preparation of the inspection environment for mass production is completed.

Next, mass production inspection is performed by the inspection method shown in the process flow chart of FIG. 4, replacing the semiconductor integrated circuit 11 to be measured with a new semiconductor integrated circuit of the same product type.

First, in the inspection item 1, the measuring device control circuit 7 sets the measuring device (1).
(N), a required measuring device is selected, an inspection condition is given to the semiconductor integrated circuit, and information of the item number is sent to the inspection condition storage / comparison circuit 1. The information of this item number is used as a synchronization signal for designating the inspection item, and is compared with the item number already stored.
To control the switching unit 3 via the control unit to select the measuring devices (1) to (n) to be used for the inspection item. Then, the output signal of the selected measuring instrument is A / D-converted, and the converted measurement data is taken in the memory 5 together with the item number and stored.

The above operation is performed for each of the inspection items from inspection item 1 to inspection item n. After all inspections of each inspection item are completed, an item number is designated, an inspection condition and measurement data corresponding to the item number are called, a waveform display process is performed, and an inspection result waveform is displayed on the display of the waveform display 6. Is displayed.

In this way, the inspection conditions and measurement data corresponding to the inspection items can be displayed without confusion, and the conventional process of decoding the inspection conditions for each inspection item in advance is eliminated, and the time required for the inspection is reduced. The waveform can be shortened, and stable waveform observation becomes possible.

As described above, according to the semiconductor integrated circuit inspection method of the present invention, the item number and the inspection condition for each inspection item are stored in advance,
Since the inspection result data is stored by associating the inspection conditions and item numbers with the stored item numbers, after all inspections are completed, the stored inspection conditions and measurement data are stored in association with the stored item numbers. By calling, the inspection conditions and measurement data corresponding to the inspection items can be displayed without confusion. Further, the conventional process of decoding the inspection conditions in advance for each inspection item is eliminated, so that the time required for the inspection can be shortened and a stable waveform observation can be achieved.

[Brief description of the drawings]

FIG. 1 is a block diagram of an inspection apparatus according to an embodiment of the present invention, FIG. 2 is a diagram for explaining a display means of an inspection result waveform, and FIG. FIG. 4 is a flowchart for explaining one embodiment, FIG. 4 is a flowchart for explaining one embodiment relating to a method of testing a semiconductor integrated circuit of the present invention, and FIG. 5 is a diagram illustrating a conventional method of testing a semiconductor integrated circuit. FIG. 1 ... inspection condition storage, comparison circuit, 2 ... control circuit, 3 ...
... Switching circuit, 4 ... A / D converter, 5 ... Memory, 6 ...
Waveform display device, 7 Measurement device control circuit, 8 Measurement device 1
... N, 9... Test result waveform display device, 10... Static characteristic tester, 11.

Claims (1)

(57) [Claims] A first step of preliminarily storing an item number of each inspection item sent from the inspection device and an inspection condition corresponding to the item number to prepare for measurement; and generating the inspection device. While applying the inspection condition to the semiconductor integrated circuit, the item number corresponding to the inspection condition is compared with the item number stored in the first step, and the semiconductor integrated circuit corresponding to the matched item number is compared. A second step of selecting an output signal; a third step of storing measurement data obtained by A / D converting the selected output signal in association with the stored item number; The second and third steps are performed in parallel, and after all inspections are completed, the stored inspection conditions and measurement data are subjected to a calling waveform display process in association with the stored item numbers. Semi-conductor including four steps Inspection method for an integrated circuit.