JPH08285783A - Macro image inspection equipment - Google Patents

Abstract

PURPOSE: To suppress fluctuation in the inspection results due to change of the installation environment. CONSTITUTION: Since a semiconductor wafer 1 is irradiated with the illumination light from an illuminator 2 through a background plate 6, an invariant background image is reflected on the illuminated surface of the semiconductor wafer 1. Consequently, even if the installing position of stage 3 or the like, other than a monitor 5, is changed it has no effect on the image and a good image is obtained constantly. Furthermore, since the illumination light from the illuminator 2 is diffused by the background plate 6, the illuminated surface of the semiconductor wafer 1 is illuminate uniformly with the illumination light. Consequently, the illumination range is widened to enlarge the observable region thus enabling observation of the entire semiconductor wafer 1.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a macro image inspection apparatus, and more particularly to a macro image inspection apparatus for macro inspection of semiconductor wafers and the like.

[0002]

2. Description of the Related Art In conventional macro inspection of semiconductor wafers,
While inclining the semiconductor wafer on the stage, the semiconductor wafer is irradiated with illumination light from above, and the specularly reflected light from the semiconductor wafer is observed with the naked eye, resulting in uneven resist (coating failure), exposure failure, defocusing, etc. Was inspected for defects. For example, the presence or absence of resist unevenness is determined by observing the color discontinuity of the interference light from the semiconductor wafer.

[0003]

However, in general, an illuminating device such as a halogen lamp is used to irradiate a semiconductor wafer with illuminating light. However, since the brightness is strong but the irradiation range is narrow, the observable area is considerably large. However, there is a problem that the semiconductor wafer must be moved in order to observe the whole, observation requires skill, and working time becomes long.

Further, although it is desired to observe only the surface state (for example, pattern) of the semiconductor wafer, if the place where the inspection apparatus is installed changes, the background image reflected on the irradiation surface of the semiconductor wafer in a mirror state also changes. However, there is a problem that it becomes difficult to observe the specular reflection light of the semiconductor wafer, and the inspection results vary.

The present invention has been made in view of the above circumstances, and its problem is to eliminate the variation of the inspection result due to the change of the installation environment of the inspection apparatus and to shorten the inspection time. Is to provide.

[0006]

In order to solve the above-mentioned problems, a macro image inspection apparatus of the present invention comprises an illuminating means for irradiating a sample with illumination light, an inclining means for inclining the sample,
In a macro image inspection apparatus including an image pickup unit that images the sample and outputs sample image data, and a display unit that displays the sample image data from the image pickup unit, diffuse illumination light from the illumination unit. The sample is provided with an illumination light transmissive member for uniformly irradiating the sample and constantly making the background image on the irradiation surface of the sample the same.

[0007]

Since the illuminating light from the illuminating means is applied to the sample through the illuminating light transmitting member, the background image reflected on the illuminated surface of the sample is always the same, and as a result, the main body of the inspection apparatus excluding the displaying means. Even if the installation location of is changed, the image is not affected by it, and a good image is always obtained. In addition, since the illumination light from the illumination means is diffused by the illumination light transmitting member, the illumination light is evenly applied to the irradiation surface of the sample, and the irradiation range is widened to expand the observable area. Can be observed.

[0008]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is an overall configuration diagram showing a macro image inspection apparatus according to an embodiment of the present invention.

In this macro image inspection apparatus, an illuminating device (illuminating means) 2 for irradiating the surface of a semiconductor wafer (sample) 1 with illuminating light and a semiconductor wafer 1 are tilted as shown by arrows a and b in FIG. Stage (tilting means) 3 and stage 3
A TV camera (imaging unit) 4 that captures an image of the upper semiconductor wafer 1 and outputs image data (sample image data), and a monitor (display unit) that displays the image data from the TV camera 4.
5 and a background plate (illumination light transmitting member) 6 described later.

The illumination device 2 and the TV camera 4 are arranged above the stage 3, respectively. The output end of the TV camera 4 is connected to the input end of the monitor 5 via the cable 7, and the monitor 5 is arranged at a place apart from the TV camera 4, the stage 3, etc. (for example, outside the clean room).

The background plate 6 is a translucent or milky white plate having a strong light diffusing property, and comprises the illuminating device 2 and the stage 3.
Is disposed between the semiconductor wafer 1 and the semiconductor wafer 1 on the stage 3 so as to diffuse the illumination light from the illumination device 2 and uniformly illuminate the semiconductor wafer 1. .

Illumination light from the illumination device 2 passes through the background plate 6 and is applied to the irradiation surface of the semiconductor wafer 1. Lighting device 2
Since the illuminating light from the device is diffused by passing through the background plate 6, the illuminating light is evenly applied to the irradiation surface of the semiconductor wafer 1.

Illumination light transmitted through the background plate 6 is substantially specularly reflected on the irradiation surface of the semiconductor wafer 1, and the specularly reflected light (image) is T.
The light enters the V camera 4 and is converted into image data.

Image data from the TV camera 4 is displayed on a monitor 5 installed outside the clean room.

The worker performs the inspection work while looking at the screen of the monitor 5 (for example, color discontinuity due to the interference light from the semiconductor wafer 1). At this time, the image displayed on the monitor 5 is
Compared to the monitor image (see Fig. 3) that does not use the background board 6,
As shown in FIG. 2, the entire semiconductor wafer 1 is clear. In addition, the entire pattern of the semiconductor wafer 1 is clearly visible, and the illumination device 2 does not appear as a background image. On the other hand, the monitor image without using the background plate 6 is shown in FIG.
As shown in FIG. 3, since the illumination light from the illumination device 2 is not diffused, the irradiation range is considerably limited, only the part 10 of the pattern can be seen, and the illumination device 2 appears as a background image.

According to the macro image inspection apparatus of this embodiment, the illumination light from the illumination device 2 is irradiated onto the irradiation surface of the semiconductor wafer 1 through the background plate 6, so that the irradiation surface of the semiconductor wafer 1 is irradiated. The background image is always the same. As a result, even if the installation location of the stage 3 and the like other than the monitor 5 changes, the image is not affected by it, so that a good image is always obtained and it is possible to prevent variations in inspection results. Further, since the illumination light from the illumination device 2 is diffused by the background plate 6, the illumination light is evenly applied to the irradiation surface of the semiconductor wafer 1 and the irradiation range is expanded to enlarge the observable area. As a result, the semiconductor wafer 1
It is possible to observe the entire semiconductor wafer 1 without frequently moving the wafer, waste of work is reduced, and inspection work time can be shortened. .

Further, since the semiconductor wafer 1 is converted into image data and displayed on the monitor 5, the semiconductor wafer 1 can be observed at a place far from the stage 3. Therefore, the dust source can be moved away from the periphery of the semiconductor wafer 1, and the environment around the semiconductor wafer 1 can be better maintained in terms of suppressing dust generation.

[0019]

As described above, according to the macro image inspection apparatus of the present invention, the background image on the irradiation surface of the sample is always the same, so that even if the inspection apparatus except the display means is installed at a different place. As a result, the image is not affected, a good image is always obtained, and variations in inspection results can be prevented. Further, since the illumination light from the illumination means is diffused by the illumination light transmitting member, the illumination light is evenly applied to the irradiation surface of the sample, the irradiation range is expanded, and the observable region is expanded. As a result, it is possible to observe a wide range of the sample without frequently moving the sample as in the conventional case, waste of work is reduced, and inspection work time can be shortened.

[Brief description of drawings]

FIG. 1 is an overall configuration diagram showing a macro image inspection apparatus according to an embodiment of the present invention.

FIG. 2 is a diagram showing a monitor image obtained by using a background plate.

FIG. 3 is a diagram showing a monitor image obtained without using a background plate.

[Explanation of symbols]

 1 semiconductor wafer 2 illumination device 3 stage 4 TV camera 5 monitor 6 background plate 7 cable

Claims (1)

[Claims] 1. Illuminating means for irradiating a sample with illumination light, tilting means for tilting the sample, imaging means for imaging the sample and outputting sample image data, and the sample image data from the imaging means. In a macro image inspection apparatus having a display means for displaying, in order to uniformly illuminate the sample by diffusing the illumination light from the illuminating means, the background image reflected on the illuminated surface of the sample is always the same. 1. A macro image inspection apparatus comprising the illumination light transmitting member of 1.