JPH0225235Y2 - - Google Patents

Description

[Detailed description of the invention] Industrial application field This invention is an electrical property testing device for electronic components, etc.
In particular, the present invention relates to an apparatus for inspecting electrical characteristics of small objects to be measured such as semiconductor devices.

Prior Art In the semiconductor manufacturing process, a specific one or a small number of semiconductor elements formed in large numbers on a semiconductor wafer are sampled, their characteristics are measured, and based on the measurement results, it is determined whether the characteristics of the entire semiconductor wafer are good or bad. There is a process to do this. This characteristic test involves contacting the probe with the electrode of the sampled semiconductor element.
This is done by passing a current and measuring the characteristics. In addition, although this type of characteristic inspection can be fully automated, the semiconductor wafers sent to automatic inspection equipment vary in size, and the sizes and electrode patterns of the semiconductor elements also vary, and inspection can only be done in one step. This process is usually performed only on a small number of sampled semiconductor elements on a single semiconductor wafer, or only on a small number of sampled semiconductor wafers, and is performed in small quantities of a wide variety of products. It is extremely disadvantageous in terms of capital investment to fully automate the inspection of Therefore, most of these inspections are performed manually as follows.

For example, a probe is visually observed and accurately brought into contact with the electrodes of sampled semiconductor elements on a single semiconductor wafer to measure their characteristics, and the results are transferred to a CRT.
The characteristic curve image is projected onto the screen of a cathode ray tube (CRT), and the characteristic curve of this CRT image is visually observed to determine whether the characteristics are good or bad. Visual observation of the state of contact between the electrodes of the semiconductor device and the probe during inspection is difficult when the electrode pattern of the semiconductor device is minute, such as an IC, by direct visual inspection, so it is necessary to use a microscope. It is done using That is, while looking at a magnified image of the semiconductor element using a microscope, a probe is brought into contact with the electrode, and then the characteristics are measured.
Inspection is performed by reading the characteristic curve of a CRT screen.

Problems that the invention aims to solve Characteristic inspections using visual observation using a microscope and CRT are performed by one worker, who first looks into the microscope and then takes his eyes off the microscope. Looking at the CRT screen required a lot of work, and the work efficiency was poor. Additionally, for workers, there is a big difference between the focus of the eyes when looking into the field of view of the microscope and the focus of the eyes when looking at the CRT screen, and the line of sight moves from the microscope to the CRT, which can cause eye fatigue. It was intense and I couldn't work for long hours.

As a solution to such problems, for example,
Publication No. 53-93488 describes that an image of the object to be measured magnified by a microscope is projected onto a CRT screen, a probe is applied to an electrode by looking at the image of the object to be measured on the CRT screen, measurement is started, and then It has been disclosed that the same CRT screen can be switched from a field image of a microscope to an image of a characteristic curve, or an image of the characteristic curve can be projected over an enlarged image of the object to be measured for visual observation. In this way, workers only need to look at the CRT screen, increasing work efficiency and reducing eye fatigue. However, there remained an inconvenient problem in that it was extremely difficult to observe the state of contact between electrodes and contacts by looking at a CRT screen.

Means for solving the problems This invention was made in view of the above problems.
A microscope for observing the contact state between the electrode of the object to be measured and a probe for testing characteristics, a characteristic measuring device for measuring the electrical characteristics of the object to be measured through the probe, and a display means for displaying an image of the measured electrical characteristics. and an image transfer means for transferring the image displayed by the display means within the field of view of the microscope.

Characteristic inspection based on this invention involves visual observation using a microscope, where a probe is brought into contact with the electrode of the object to be measured to begin measuring the characteristics, and then the measurement results are displayed as an image on a display means, and the image is displayed on the microscope. This is done by visually observing the metastatic image that has been transferred to the visual field.

Effect: According to the above means, an enlarged image of the object to be measured and an image of its characteristic curve are projected in the field of view of the microscope, so the operator only has to look through the microscope, and there is no sudden change in focus. There is less eye fatigue and work efficiency is further improved.

Embodiment An embodiment of the present invention applied to, for example, an apparatus for testing the characteristics of sampled semiconductor elements on a semiconductor wafer will be described below with reference to the drawings.

In the drawings, reference numeral 1 denotes a semiconductor wafer, which has a large number of semiconductor elements 2. Reference numeral 3 denotes a characteristic measuring device that measures the characteristics by applying a probe 5 to the electrode 4 of the sampled element 2 on the semiconductor wafer 1, and 6 a microscope that magnifies and visually observes the peripheral area including the semiconductor element 2 whose characteristics are to be measured. , 7 is a display means for displaying the characteristics of the semiconductor element 2 whose characteristics have been measured, for example.
The CRT display device 8 is an image transfer means for transferring the characteristic waveform displayed on the screen of the CRT 9 of the CRT display device 7 to the field of view of the microscope 6, and is, for example, an optical fiber.

The characteristic measuring device 3 includes, for example, a movable table 10 on which one semiconductor wafer 1 is positioned and mounted, a measurement plate 11 called a probe card that supports a probe 5 above the movable table 10, and a probe 5 via the measurement plate 11. 5 and a characteristic measuring circuit (not shown) electrically connected to the circuit. The measuring plate 11 has an opening 12 in the center, and a probe 5 is inserted into the opening 12.
extends. When the semiconductor wafer 1 is supplied onto the movable table 10, the movable table 10 is operated so as to bring the tip of the probe 5 into contact with the electrode 4 of the sampled semiconductor element 2.

The microscope 6 is for visually observing the semiconductor wafer 1 through the opening 12 by disposing an objective lens 13 near the upper part of the opening 12 of the measurement plate 11.
The visual field image seen through the eyepiece lens 14 of the microscope 6 before the characteristic test is an enlarged image a of the semiconductor element 2 and the probe 5, as shown in FIG. 3A. The operator visually observes this enlarged image a to determine whether the contact state between the electrode 4 and the probe 5 is good, and if the contact state is good, characteristic measurement is started. The data of the characteristic measurement results are sent to the CRT display device 7 in the form of electrical signals, and displayed on the screen of the CRT 9 as a characteristic curve as shown in image b shown in FIG.

Further, a semi-transparent mirror 15 is installed in a part of the optical path of the microscope 6, and a lens 1 is installed in a part of the side wall where the semi-transparent mirror 15 is located.
One end of the optical fiber 8 is connected via an attachment 17, and the other end of the optical fiber 8 is connected via an attachment 17.
Connected to CRT9 screen. The semi-transparent mirror 15 passes the light incident from the objective lens 13 and reflects the light incident from the optical fiber 8 via the lens 16 to the eyepiece 14.

In the above embodiment, the characteristic test of the semiconductor element 2 is performed as follows. First, the operator observes the visual field image a of the microscope 6, brings the probe 5 into contact with the electrode 4 of the semiconductor element 2, and starts measuring the characteristics. When the characteristics are measured, the results are displayed on the screen of the CRT 9, and this displayed image b passes through the optical fiber 8, becomes the desired size with the lens 16, is reflected by the semi-transparent mirror 15, and enters the optical path of the microscope 6. Enter, eyepiece 14
It enters the worker's eyes. At this time, the visual field image of the microscope 6 is a composite image c of the semiconductor element enlarged image a and the characteristic display image b, as shown in FIG. The characteristic curve d is visually observed to judge whether the characteristic is good or bad.

As explained in the above embodiment, instead of observing the composite image c of the enlarged semiconductor element image a and the characteristic display image b, for example, a shutter may be provided in a part of the optical path of the enlarged semiconductor element image a. When the characteristic display image b is displayed on the characteristic display means, the shutter is automatically closed by this image signal, and the semiconductor element enlarged image a and the characteristic display image b are alternately displayed within the same field of view. You may also try observing.

The present invention is not limited to the above embodiments, and for example, a liquid crystal display device other than CRT or an EL display device may be used as the characteristic display means. Further, this display means may be integrated into the characteristic measuring device.
Further, the display means may be placed directly on a part of the side wall where the semi-transparent mirror 15 is located. Furthermore, the present invention is not limited to testing the characteristics of semiconductor elements, but can be fully applied to any device that tests the characteristics using a microscope and a characteristic display means.

Effects of the invention According to the invention, a worker can observe the contact state of the electrode and probe of the object to be measured by simply looking through a microscope.
Since characteristic curves can be observed, work efficiency is further improved and eye fatigue is reduced.

[Brief explanation of drawings]

FIG. 1 is an overall perspective view showing an embodiment of the present invention, FIG. 2 is a schematic diagram of the operating principle of the device shown in FIG. 1, and FIG. 3 is an image diagram at each point in FIG. 2. 2...Object to be measured (semiconductor element), 3...Characteristics measuring device, 4...Electrode, 5...Sensor, 6...Microscope, 7...Display means (CRT display device), 8...Image transfer means (optical fiber).

Claims (1)

[Claims for Utility Model Registration] A microscope for observing the state of contact between an electrode of an object to be measured and a probe for testing characteristics, a characteristic measuring device for measuring the electrical characteristics of an object to be measured through the probe, An electrical property testing device comprising: a display unit that displays an image of electrical properties; and an image transfer unit that transfers the image displayed by the display unit within the field of view of the microscope.