JPH0442914Y2 - - Google Patents

Description

[Detailed description of the invention] [Industrial application field] The present invention is suitable as an illumination device for a device that uses automatic image measurement processing to identify defective products such as chips in the polishing process of silicon wafers, for example. .

[Prior art]

Conventionally, when inspecting defective products such as chips in silicon wafers after wrapping, illumination is applied from below the silicon wafer, but the lapping liquid that adheres to the silicon wafer in the form of droplets falls onto the illuminator, staining the illuminator and reducing the illuminance. Furthermore, since the workpiece mounting table is located in the center of the illuminator, it takes time to wipe it off. In addition, when image processing is performed using an automatic image measuring device, dirt is detected as noise, so the dirt must be wiped off each time, resulting in poor work efficiency and difficulty in automation.

[Purpose of invention]

SUMMARY OF THE INVENTION In view of the above drawbacks, the present invention proposes a lighting device that has a simple structure and can be automated by preventing the lighting device from being contaminated with dirty liquid such as wrapping liquid.

[Structure of the idea]

The present invention includes a liquid reservoir that stores liquid in a case body, a liquid circulation mechanism that circulates the liquid, and a liquid reservoir that protrudes upward from the upper surface of the liquid in the liquid reservoir and is formed to have a diameter smaller than the outer diameter of the workpiece. The present invention includes a workpiece mounting table on which a workpiece is placed, and a light source that irradiates light through the liquid.

〔Example〕

The present invention will be described above with reference to one embodiment shown in the drawings. In the lighting device, as shown in FIGS. 1 and 2, a liquid reservoir 3 for storing liquid 2 is fixed to the upper part of a case body 1, and a supply side boat 4 and a discharge side port 5 of a liquid circulation mechanism are connected to the liquid reservoir 3. A liquid 2 is circulated and supplied through a plurality of pipes 6 and 7. In FIG. 1, four injection ports 6a and three discharge ports 7a are provided. A workpiece mounting table 8 is closely fixed to the upper surface of the liquid reservoir 3, and an illuminator 9, which is a light source that emits light upward, is provided on the lower side of the liquid reservoir 3. The workpiece 10 is illuminated by the light source of the illuminator 9 that passes through the bottom plate 3a of the liquid reservoir 3 and the liquid 2.

The liquid 2 may be any liquid, but for example, fluorocarbon, alcohol, etc. are used.

It is preferable that a material having a diffusion effect be used for the bottom part 3a of the liquid reservoir 3 so that the light transmitted through the bottom plate 3a becomes uniform light.

The workpiece mounting table 8 has a height that protrudes above the upper surface of the liquid 2, and has an outer diameter of 8 cm, which is smaller than the outer diameter of the workpiece 10 of, for example, 10 cm x 10 cm or 10 cm in diameter, which is placed on the workpiece mounting table 8. ing.

When automatic image processing of the workpiece 10 is carried out using the above-mentioned illumination device, an automatic image measurement device (not shown) is installed above the workpiece 10, and the workpiece 10 is, for example, a silicon wafer to which wrapping liquid after wrapping has adhered in the form of droplets. The workpiece is placed on a workpiece mounting table 8 by a robot (not shown) with the wrapping surface facing downward, and is irradiated with light from an illuminator 9 serving as a light source.

At this time, even if the wrapping liquid adhering in the form of droplets separates from the silicon wafer and falls on the shock placed on the workpiece mounting table 8, the liquid 2 circulating below flows from the inlet 6a toward the outlet 7a. Since the wrapping liquid is diluted and does not accumulate in one place, it is irradiated with light of uniform illuminance. The workpiece 10 on which the image measurement process for defects such as chips due to wrapping has been completed is sent to the next process by the robot.

When the illumination device is configured as described above, the illuminator 9 is prevented from being soiled by the wrapping liquid, so there is no need to wipe it off, and the measurement process is automated because the illuminant is always irradiated with light with uniform illuminance. As a result, work efficiency is significantly improved, and erroneous judgments due to noise caused by dirt do not occur in automatic image measurement processing.

In the structure described above, the liquid 2 does not flow inside the workpiece mounting table 8, but it may be configured so that it flows.

Further, the height of the liquid reservoir 3 may be increased to allow the liquid 2 to flow therein, and a waterproof illuminator 9 may be placed in the liquid 2 to illuminate the workpiece 10.

The flow rate of the liquid 2 is adjusted at the supply side port 4 and the discharge side port 5 of the liquid circulation mechanism, and the liquid 2 flows in the opposite direction.
It may be configured to flow.

[Effect of idea]

Since the present invention is constructed as described above, even if the dirty liquid adhering to the workpiece falls, it is diluted by the flowing liquid and is flowed away without accumulating in one place, so that the illuminance of the illumination can be uniformly applied to the workpiece. It is possible to provide an illumination device that has excellent practical effects, such as being able to automate image measurement processing and significantly improving work efficiency, since the work of wiping off dirt is not required.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention, and FIG. 1 is a plan view of the lighting device, and FIG. 2 is a cross-sectional side view of the main part of the lighting device. DESCRIPTION OF SYMBOLS 1...Case body, 2...Liquid, 3...Liquid reservoir, 4, 5, 6, 7...Liquid circulation mechanism, 8...Workpiece mounting table, 9...Light source illuminator, 10...Workpiece .

Claims (1)

[Scope of utility model registration request] A liquid reservoir for storing liquid in a case body, a liquid circulation mechanism for circulating the liquid, and a workpiece protruding upward from the upper surface of the liquid in the liquid reservoir and having a smaller diameter than the outer diameter of the workpiece. An illumination device comprising: a workpiece mounting table that emits light through the liquid; and a light source that emits light through the liquid.