JP2022146021A - Optical circuit manufacturing method - Google Patents

Abstract

To solve a problem, in manufacturing an optical circuit having a waveguide formed therein, with regard to adverse effects, etc., on environment of a sharp rise of manufacturing cost, an extended lead time period and a chip disposal, without discarding the optical circuit due to acquisition of desired characteristics, even when there is inclusion of foreign matter in the waveguide path.SOLUTION: The present disclosure is an optical circuit manufacturing method characterized by comprising, in order: an image photographing step S1 for capturing an image of an optical circuit having a waveguide formed therein; a foreign matter detection step S2 for detecting foreign matter in a path of the waveguide from the captured image of the optical circuit; and a detour path drawing step S7 for drawing, by a laser, a detour path to bypass foreign matter in the vicinity of the foreign matter.SELECTED DRAWING: Figure 2

Description

TECHNICAL FIELD The present disclosure relates to techniques for manufacturing waveguide-formed optical circuits.

Japanese Unexamined Patent Application Publication No. 2002-200002 discloses a technique for manufacturing an optical circuit having a waveguide. Here, in the prior art of Patent Document 1, an optical circuit with a waveguide formed therein is manufactured in the order of undercladding film deposition, core film deposition, waveguide formation, and overcladding film deposition. On the other hand, the solution of Patent Document 1 uses a femtosecond laser to fabricate an optical circuit with a waveguide.

JP-A-9-311237

However, in the prior art of Patent Document 1, the waveguide is not formed or is damaged when foreign matter enters the path of the waveguide. There are problems such as long lead times and adverse effects on the environment due to chip disposal. On the other hand, in the solution of Patent Document 1, since the laser focal point moves relatively, each waveguide can be flexibly drawn by laser, but many waveguides cannot be efficiently drawn by laser. is difficult, and there are problems in terms of mass production.

Therefore, in order to solve the above-described problems, the present disclosure provides a method for manufacturing an optical circuit having a waveguide formed thereon, so that even when foreign matter is mixed in the path of the waveguide, the optical circuit can be discarded with desired characteristics. First, the object is to solve problems such as a rise in manufacturing cost, a long lead time, and an adverse effect on the environment due to chip disposal.

In order to achieve the above object, after detecting a foreign substance on the path of the waveguide from the photographed image of the optical circuit, a bypass path for bypassing the foreign substance is drawn in the vicinity of the foreign substance by laser drawing.

Specifically, the present disclosure includes an image capturing step of capturing an image of an optical circuit in which a waveguide is formed, a foreign matter detecting step of detecting a foreign substance on the path of the waveguide from the captured image of the optical circuit, and and a detour drawing step of laser-drawing a detour bypassing the foreign matter in the vicinity of the foreign matter.

According to this configuration, even when foreign matter is mixed in the path of the waveguide, the desired characteristics are obtained and the optical circuit is not discarded. It is possible to solve the problem in terms of

Further, in the present disclosure, the foreign matter detection step detects the foreign matter using at least one of a non-defective product image, a defective product image, and a defective portion of the defective product image as teacher data. An optical circuit manufacturing method characterized by:

According to this configuration, it is possible to detect a foreign object on the path of the waveguide based on any of the above teaching data (learning processing by artificial intelligence may be used).

Further, according to the present disclosure, the foreign matter detection step includes: a size of a high-brightness portion of the captured image; a position of the high-brightness portion of the captured image; and a difference in brightness between the low-brightness portion and a low-brightness portion.

According to this configuration, it is possible to detect a foreign object on the path of the waveguide based on any one of the above size, position, and luminance difference (learning processing by artificial intelligence may be used).

Further, according to the present disclosure, based on the position of the waveguide in the vicinity of the foreign matter, it is determined whether there is a space for laser-drawing the detour in the vicinity of the foreign matter, and when it is determined that there is the space, and a detour determination step of determining a position where the detour is drawn by laser near the foreign matter, between the foreign matter detection step and the detour drawing step.

According to this configuration, it is possible to determine the laser drawing position of the detour after determining whether or not the detour can be laser drawn based on the position of the waveguide near the foreign object.

In this way, in manufacturing an optical circuit in which a waveguide is formed, even if foreign matter is mixed in the path of the waveguide, the present disclosure can obtain the desired characteristics without discarding the optical circuit, thereby increasing the manufacturing cost. , long lead times, and adverse effects on the environment due to chip disposal can be solved.

1 is a diagram showing the configuration of an optical circuit manufacturing system of the present disclosure; FIG. FIG. 4 illustrates the steps of the optical circuit manufacturing process of the present disclosure; FIG. 4 is a diagram showing a specific example of a foreign object detection process of the present disclosure; FIG. 4 is a diagram showing a specific example of a foreign object detection process of the present disclosure; FIG. 4 is a diagram showing a specific example of a detour drawing process of the present disclosure;

Embodiments of the present disclosure will be described with reference to the accompanying drawings. The embodiments described below are examples of implementing the present disclosure, and the present disclosure is not limited to the following embodiments.

FIG. 1 shows the configuration of the optical circuit manufacturing system of the present disclosure. The steps of the optical circuit fabrication process of the present disclosure are illustrated in FIG. An optical circuit manufacturing system L includes an image capturing device 1 , a foreign object detection device 2 and a laser drawing device 3 . The foreign matter detection device 2 includes a foreign matter detection unit 21 and a detour determination unit 22, and can be implemented by installing a foreign matter detection program for steps S2 to S6 in a computer.

First, a waveguide-formed optical circuit is fabricated. Here, as in the prior art of Patent Document 1, an optical circuit having a waveguide formed therein may be manufactured in the order of undercladding film deposition, core film deposition, waveguide formation, and overcladding film deposition. On the other hand, similarly to the solution of Patent Document 1, femtosecond laser may be used to manufacture an optical circuit having a waveguide.

The image capturing device 1 captures an image of the optical circuit in which the waveguide is formed (step S1). Here, when the image capturing device 1 is an optical microscope, it has a narrow viewing angle and takes time to capture an image of an optical circuit, but can capture an image of minute foreign matter. On the other hand, when the imaging apparatus 1 is a multi-spectral illumination linked camera, it has a wide viewing angle and can take an image of a minute foreign matter without taking time to take an image of an optical circuit.

The foreign matter detector 21 detects foreign matter on the path of the waveguide from the photographed image of the optical circuit (step S2). Then, when the foreign matter detector 21 detects a foreign matter on the path of the waveguide (YES in step S3), the processes from step S4 onward are executed. On the other hand, when the foreign object detection unit 21 does not detect any foreign object on the waveguide path (NO in step S3), the processes from step S4 onward are stopped.

Here, the foreign matter detection unit 21 detects a foreign matter using at least one of a non-defective product image, a defective product image, and a defective portion of the defective product image as teaching data (step S2). Then, the foreign object detection unit 21 determines the size of the high-brightness portion of the captured image, the position of the high-brightness portion of the captured image, and the high-brightness and low-brightness portions of the captured image. A foreign object is detected based on at least one of the luminance difference between the two (step S2).

A specific example of the foreign matter detection process of the present disclosure is shown in FIG. In FIG. 3, the foreign matter detection unit 21 simply compares a non-defective product image prepared in advance with a newly captured image.

In the first row of FIG. 3, a good image PC of the optical circuit is shown. In the second row of FIG. 3, a photographed image PL of the optical circuit is shown. In the image shown in FIG. 3, the whiter portions have higher brightness, the blacker portions have lower brightness, and the contrast between the white and black portions is emphasized compared to the actual image.

Here, in the photographed image PL of the optical circuit, the waveguides, dicing lines D, and polishing markers G formed in the optical circuit are photographed in the same manner as the non-defective product image PC of the optical circuit. A waveguide formed in an optical circuit has a narrow shape, is located within the chip of the optical circuit, and has a low brightness. The dicing line D has a thick shape, is positioned at the chip edge of the optical circuit, and has high brightness. The polishing marker G has a large shape, is located at the chip edge of the optical circuit, and has high brightness.

On the other hand, in the photographed image PL of the optical circuit, unlike the non-defective product image PC of the optical circuit, the foreign matter C on the path of the waveguide is photographed. A foreign object C on the waveguide path has a small shape, is located on the waveguide path, and has a high brightness. Therefore, it is possible to distinguish between the foreign matter C on the path of the waveguide and the waveguide, dicing line D and polishing marker G formed in the optical circuit.

As an object to be compared with the newly captured image, one good product image prepared in advance may be used, an average image of two or more good product images prepared in advance may be used, or other newly taken images may be used. It's okay. Also, the image shown in FIG. 3 may be smoothed.

A specific example of the foreign matter detection process of the present disclosure is also shown in FIG. In FIG. 4, the foreign matter detection unit 21 AI-learns a non-defective product image prepared in advance and a defective product image prepared in advance.

In the first stage of FIG. 4, a good product image PC1 and a defective product image PD1 of the optical circuit are shown. The second stage of FIG. 4 shows a good product image PC2 and a defective product image PD2 of the optical circuit. The third stage of FIG. 4 shows a good product image PC3 and a defective product image PD3 of the optical circuit. The fourth stage of FIG. 4 shows a good product image PC4 and a defective product image PD4 of the optical circuit. In the images shown in the entire row of FIG. 4, the whiter portions are brighter, and the blacker portions are lower in brightness. Except for the image shown in the second row of FIG. It is emphasized compared to the actual image.

As the non-defective product image PC1 of the optical circuit, an image similar to the non-defective product image PC of the optical circuit shown in the first stage of FIG. 3 is AI-learned. As the defective product image PD1 of the optical circuit, an image similar to the photographed image PL of the optical circuit shown in the second row of FIG. 3 and the position of the foreign matter C on the path of the waveguide are AI-learned. As the non-defective product image PC2 of the optical circuit, an image obtained by changing the color tone of the non-defective product image PC1 of the optical circuit is AI-learned. As the defective optical circuit image PD2, an image obtained by changing the color tone of the defective optical circuit image PD1 and the position of the foreign matter C on the path of the waveguide are AI-learned.

As the non-defective product image PC3 of the optical circuit, AI learning is performed on an upside-down image of the non-defective product image PC1 of the optical circuit. As the optical circuit defective product image PD3, AI learning is performed on an upside down image of the optical circuit defective product image PD1 and the position of the foreign matter C on the path of the waveguide. As the non-defective product image PC4 of the optical circuit, an image obtained by cutting out a part of the non-defective product image PC1 of the optical circuit is AI-learned. As the defective optical circuit image PD4, an image obtained by cutting out a part of the defective optical circuit image PD1 and the position of the foreign matter C on the path of the waveguide are AI-learned.

Then, it is possible to extract the size of a high-brightness portion, the position of a high-brightness portion, and the brightness difference between a high-brightness portion and a low-brightness portion as feature amounts. Then, in the photographed image PL of the optical circuit shown in the second stage of FIG. 3, it is possible to identify whether it is a non-defective product image or a defective product image. Furthermore, in the photographed image PL of the optical circuit shown in the second stage of FIG. 3, the position of the foreign matter C on the path of the waveguide can be extracted.

In addition to the images shown in FIG. 4 as the non-defective product images and the defective product images to be AI-learned, instead of subjecting only similar images to AI learning, the learning images are padded by an appropriate number and type. The accuracy of foreign matter detection can be improved without detecting only foreign matter. Also, the image shown in FIG. 4 may be smoothed.

The laser lithography device 3 laser-draws a detour path that circumvents the foreign matter near the foreign matter (step S7). Here, the detour determination unit 22 executes steps S4 to S6 as follows.

A specific example of the detour drawing process of the present disclosure is shown in FIG. The first and second stages of FIG. 5 show captured images PL of the optical circuit. In the third stage of FIG. 5, an optical circuit chip LC is shown. In the images shown in the first and second stages of FIG. 5, the darker the area, the higher the brightness, and the whiter the area, the lower the brightness.

In the first stage of FIG. 5, the foreign matter detector 21 detects the waveguides W1 and W2, the dicing line D, the polishing marker G, and the foreign matter C on the path of the waveguide W1 (steps S2 and S3). ).

In the second stage of FIG. 5, the detour determination unit 22 determines whether there is a space for laser-drawing the detour B near the foreign object C based on the positions of the waveguides W1 and W2 near the foreign object C. (step S4). Then, when the detour determination unit 22 determines the presence of the above space (YES in step S5), the processes from step S6 onward are executed. On the other hand, when the detour determination unit 22 determines that the space does not exist (NO in step S5), the processes from step S6 onward are stopped.

In other words, the detour determining unit 22 determines that another waveguide W2 is not positioned above the waveguide W1 on which the foreign object C is positioned on the paper surface, and determines that the detour drawing space SB exists. (YES in step S4 and step S5). On the other hand, the detour determination unit 22 determines that another waveguide W2 is positioned below the waveguide W1 in which the foreign object C is positioned on the path, and determines that the detour non-drawing space SW exists. is determined (NO in steps S4 and S5).

Then, when the detour determination unit 22 determines that there is the space (YES in step S5), the detour determination unit 22 determines the position where the detour B is laser-drawn near the foreign object C (step S6). On the other hand, when the detour determination unit 22 determines that there is no space (NO in step S5), the detour determination unit 22 stops the process of determining the position where the detour B is laser-drawn in the vicinity of the foreign object C. FIG.

That is, the detour determination unit 22 determines the positions of the detour/waveguide contacts P1 and P2 on both sides of the location where the foreign matter C is located in the waveguide W1 on which the foreign matter C is located. Then, the detour decision unit 22 decides the positions of the directional couplers B1 and B2 in the vicinity of the detour/waveguide contacts P1 and P2. Further, the detour determination unit 22 determines the position of the foreign matter detour point B3 in the middle of the detour/waveguide contacts P1 and P2 (step S6).

Here, the directional couplers B1, B2 are 100% directional couplers, and the coupling length of the directional couplers B1, B2 is based on the refractive index, width and height of the waveguide W1 and the detour B. determined by The foreign matter detour point B3 is a point that is not coupled to the waveguide W1, and the distance from the waveguide W1 is determined based on the refractive index, width and height of the waveguide W1 and the detour B. .

In the third stage of FIG. 5, the laser drawing device 3 laser-writes the detour B in the vicinity of the foreign object C (at the position of step S6) (step S7). Here, the laser drawing device 3 uses a femtosecond laser. Then, the laser drawing device 3 draws the detour B by laser-drawing the directional couplers B1 and B2 and the foreign matter detour B3 (step S7).

In this way, even when foreign matter C is mixed in the path of the waveguide, the desired characteristics are obtained and the optical circuit is not discarded. You can solve the problem on the surface.

Here, based on any of the teacher data shown in FIGS. 3 and 4 (learning processing by artificial intelligence may be used), foreign matter C on the path of the waveguide can be detected.

Then, based on any of the size, position and luminance difference shown in FIGS. 3 and 4 (learning processing by artificial intelligence may be used), the foreign matter C on the path of the waveguide can be detected. can.

Furthermore, based on the position of the waveguide in the vicinity of the foreign object C, it is possible to determine the laser drawing position of the detour B after determining whether or not the detour B can be laser drawn.

The method for manufacturing an optical circuit according to the present disclosure achieves desired characteristics and does not discard the optical circuit even when foreign matter is mixed in the path of the waveguide when manufacturing an optical circuit in which a waveguide is formed, thereby reducing the manufacturing cost. It is possible to solve problems in terms of adverse effects on the environment due to soaring prices, lengthening of lead time, and disposal of chips.

L: optical circuit manufacturing system 1: imaging device 2: foreign matter detection device 3: laser drawing device 21: foreign matter detection unit 22: detour determination unit PC: non-defective product image PL: photographed image D: dicing line G: polishing marker C: Foreign matter PC1, PC2, PC3, PC4: Non-defective product images PD1, PD2, PD3, PD4: Defective product images W1, W2: Waveguide SB: Detour drawing space SW: Detour non-drawing space P1, P2: Detour/waveguide Contact LC: Optical circuit chip B: Detours B1, B2: Directional coupler B3: Foreign matter detour location

Claims (4)

an image capturing step of capturing an image of the optical circuit in which the waveguide is formed;
a foreign matter detection step of detecting a foreign matter on the path of the waveguide from the photographed image of the optical circuit;
a detour drawing step of laser-drawing a detour that bypasses the foreign matter in the vicinity of the foreign matter;
A method for manufacturing an optical circuit, comprising: In the foreign matter detection step, at least one of a non-defective product image, a defective product image, and a defective part in the defective product image is used as teacher data to detect the foreign substance. The optical circuit manufacturing method according to claim 1 . The foreign object detection step includes detecting the size of a high-brightness portion of the captured image, the position of the high-brightness portion of the captured image, and the high-brightness and low-brightness portions of the captured image. 3. The optical circuit manufacturing method according to claim 1, wherein the foreign matter is detected based on at least one of a luminance difference between and. Based on the position of the waveguide in the vicinity of the foreign matter, it is determined whether there is a space for laser drawing the detour in the vicinity of the foreign matter, and when it is determined that there is the space, the detour is written as the above. a detour determination step of determining a position to be laser-drawn near the foreign object;
is provided between the foreign matter detection step and the detour drawing step.

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