JPH1123873A - Method for slitting optical waveguide component - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide the slitting method for an optical waveguide component which facilitates the formation of a slit, prolongs the life of a blade, and hardly cracks the slit. SOLUTION: The slit 27 for inserting an optical component into an optical waveguide core 22 is formed by etching and mechanical cutting in an optical waveguide component having an optical waveguide formed of an inside clad 21, the optical waveguide core 22, and an outside clad 23 on an Si substrate 10. Consequently, The cutting quantity of the hard optical waveguide part becomes small and damage to the blade 20 at the time of the formation of the slit 27 is reduced. The etched slit 27 hardly cracks.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a slit for inserting an optical component (such as a dielectric multilayer filter or a reflection mirror) at a predetermined position in an optical waveguide core formed on a Si substrate. The present invention relates to a method for efficiently forming the same.

[0002]

2. Description of the Related Art As shown in FIG.
An optical waveguide 20 is provided on an i-substrate 10.
20 is an inner cladding 21, an optical waveguide core 22, an outer cladding
Consists of 23 and others. This optical waveguide component is, for example,
An inner cladding layer 21 mainly made of quartz is formed on a Si substrate 10, an optical waveguide core 22 layer is formed thereon, and portions of the optical waveguide core 22 other than the optical waveguide core 22 are etched by etching. It is manufactured by removing and then forming the outer cladding layer 23. By the way, the optical waveguide core
13, a slit 27 for inserting an optical component is often formed in a direction crossing the optical waveguide core 22, as shown in FIG. Slit 27 is several tens of μm to suppress light loss
It needs to be formed to a width w of the order of magnitude, and an etching method or a mechanical cutting method using a dicing saw is used for the formation. As the blade (blade) of the dicing saw, a blade bonded with a metal material suitable for narrow cutting is usually used.

[0003]

However, an optical waveguide core is required.
The reason why the slit 27 is formed in the optical waveguide 22 is that the optical waveguide is made of quartz and hard, so that the blade is easily damaged, and as shown in FIG. However, there is a problem that the number increases. An object of the present invention is to lengthen the life of a blade in slit formation,
Moreover, it is an object of the present invention to provide a method for forming a slit in an optical waveguide component in which the slit is unlikely to be chipped.

[0004]

According to the first aspect of the present invention,
A slit for inserting an optical component into the core by etching and mechanical cutting is formed in an optical waveguide component provided with an optical waveguide comprising an inner clad, an optical waveguide core, and an outer clad on a Si substrate. This is a method for forming a slit in an optical waveguide component.

According to a second aspect of the present invention, there is provided a method of forming a slit for inserting an optical component into the core of an optical waveguide component provided with an optical waveguide comprising an inner cladding, an optical waveguide core and an outer cladding on a Si substrate. Forming a groove of a predetermined depth in the outer cladding at a position where the slit is to be formed by etching, and forming a slit by mechanical cutting along the groove to form a slit in the optical waveguide component. is there.

According to a third aspect of the present invention, there is provided a method of forming a slit for inserting an optical component into a core of an optical waveguide component, the slit being formed on a Si substrate having a projection at a position where the slit is formed. An inner clad, an optical waveguide core, and an outer clad are sequentially provided, and are formed by mechanically cutting along a projection provided on the Si substrate.

According to a fourth aspect of the present invention, there is provided a method of forming a slit for inserting an optical component into a core of an optical waveguide component, the slit being formed on a Si substrate having a projection at a position where the slit is formed. An inner clad, an optical waveguide core, and an outer clad are sequentially provided, an etching groove is formed at a predetermined depth from the outer clad surface along the projection provided on the Si substrate, and the groove is mechanically cut along the groove. This is a method for forming a slit in an optical waveguide component.

According to a fifth aspect of the present invention, there is provided a method for forming a slit in an optical waveguide component, wherein the protrusion provided on the Si substrate according to the third aspect penetrates the inner cladding.

According to a sixth aspect of the present invention, there is provided a method for forming a slit in an optical waveguide component, wherein the projection provided on the Si substrate according to the fourth aspect penetrates the inner cladding.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A method for forming a slit in an optical waveguide component according to the present invention will be specifically described below with reference to the drawings.
FIG. 1 is a longitudinal sectional view showing a first example of the slit forming method according to the first aspect. According to this method, an etching portion 24 penetrating through the inner cladding 21 from an optical waveguide core (hereinafter abbreviated as core) 22 is formed in advance, and the etching portion 24 is formed.
Cut the substrate 10 with the blade 30 so that
Is formed and manufactured. FIG. 2 is a view during the formation of the slit. The width of the etched portion 24 is slightly wider than the thickness of the blade 30, so that the blade 30 is a hard optical waveguide.
No contact with 20 parts at all. Therefore, the blade 30 hardly deteriorates. Further, since the etched portion 24 is formed in advance, the slit is unlikely to be chipped during cutting.

FIG. 3 is a longitudinal sectional view showing a second example of the slit forming method according to the first aspect. The etched portion 24 of the optical waveguide component shown in FIG. 3 is formed to a position slightly beyond the core 22. FIG. 4 is a vertical sectional view showing an example of the slit forming method according to the second aspect. The etched portion 24 of the optical waveguide component is formed up to just before the core 22. Also in this embodiment, since the etching portion 24 is formed in advance, the slit 27 is not easily chipped during cutting. In addition, the amount of cutting of the hard optical waveguide 20 is reduced only in the etched portion 24, and damage to the blade 30 is reduced. In addition to reducing damage to the blade and suppressing chipping of the slit portion, there is an advantage that the etching time is short and the productivity is high. In the example shown in FIG. 4, since the slit serves as a blade cutting surface, the slit width of the core 22 becomes uniform.

The etching portion 24 can be easily formed by selectively etching the surface of the optical waveguide component shown in FIG. 12 except for the etching portion 24 by photolithography. The location where the etched portion 24 is formed may or may not include the core 22 portion. The etching depth may be the entire optical waveguide, a part thereof, or a depth penetrating the Si substrate. For the etching, a dry etching method, a reactive ion etching method, a wet etching method, or the like can be applied.

FIGS. 5 and 6 are a longitudinal sectional view and a plan view, respectively, showing a fourth example of the slit forming method according to the present invention.
This is a portion obtained by linearly etching a portion of the portion forming the slit that is outside the core 22 portion, and mechanically cutting along the etching line to form the slit. When the slit is formed in this way, the slit always becomes a blade cutting surface, and the slit width becomes uniform. Further, the amount of cutting of the hard optical waveguide portion is reduced only in the etched portion 24, and damage to the blade is reduced. The method shown in FIGS.
It is difficult to form the etched surface perpendicular to the length direction of the core 22 due to limitations such as the etching method.If the etched portion is formed in the core 22 portion, the slit width of the core portion is increased, and the slit width is increased. This is suitable for the case where is uneven.

FIGS. 7 and 8 are a longitudinal sectional view and a plan view showing a first example of the slit forming method according to the third aspect. This is one in which the optical waveguide 20 is provided on the Si substrate 10 in which the projection 25 is formed in a portion excluding the core 22 among the slit forming portions, and is mechanically cut along the projection 25. Form a slit. In this case, the core portion becomes a cutting surface and its width becomes uniform. Further, the amount of cutting of the hard optical waveguide portion is reduced by the protrusion 25 of the Si substrate, but since the height of the protrusion 25 is equal to the thickness of the optical waveguide 20, damage to the blade is significantly reduced. The reason for forming the protruding portion 25 except for the core 22 portion is that, when the protruding portion 25 is formed by etching, the protruding portion 25 is often formed in a trapezoidal cross section, so that the slit width of the core 22 portion cannot be formed narrower. It is. FIG. 9 is a longitudinal sectional view and a plan view showing a second example of the slit forming method according to the third aspect. In this case, the protrusion 25 occupies half of the thickness of the optical waveguide 20.

FIGS. 10 and 11 are longitudinal sectional views showing an example of the slit forming method according to the fourth aspect. This is one in which an optical waveguide 20 is provided on a Si substrate 10 in which a protrusion 25 is formed in a portion excluding a core portion among slit forming portions, and is linearly etched along the protrusion 25. A slit is formed by mechanically cutting along the etching line. In this case, the core portion becomes a cutting surface, the width of which becomes uniform, and the chipping of the slit hardly occurs. In addition, the amount of cutting of the hard optical waveguide portion is reduced only in the etched portion 24 and the protruding portion 25, and damage to the blade is reduced. The one shown in FIGS. 10 and 11 has a lower projection,
The etching can be made shallower, so that the etching time can be shortened as compared with the case where only the protrusions or the etched portions are formed. The protrusions may be formed intermittently, and the etching portions may be formed continuously. In FIG. 11, the hard optical waveguide portion to be cut is extremely small, and the damage to the blade is significantly reduced.

[0016]

As described above, according to the slit forming method of the present invention, the amount of cutting of the hard optical waveguide portion is reduced only in the etched portion and / or the protruding portion of the Si substrate. Damage is reduced. When the core portion is cut, the core portion becomes a cut surface and its width becomes uniform. In the case where the etching portion is provided, the slit is less likely to be chipped. Therefore, an industrially remarkable effect is achieved.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing a first example of the slit forming method of the first embodiment.

FIG. 2 is a longitudinal sectional view showing a state where a slit of FIG. 1 is inserted.

FIG. 3 is a longitudinal sectional view showing a second example of the slit forming method according to the first embodiment.

FIG. 4 is a longitudinal sectional view showing a third example of the slit forming method according to claim 2;

FIG. 5 is a longitudinal sectional view showing a fourth example of the slit forming method according to the first embodiment.

FIG. 6 is a plan view of FIG. 5;

FIG. 7 is a longitudinal sectional view showing a second example of the slit forming method according to claim 3;

FIG. 8 is a plan view of FIG. 7;

FIG. 9 is a longitudinal sectional view showing a third example of the slit forming method according to the third embodiment.

FIG. 10 is a longitudinal sectional view showing a second example of the slit forming method according to claim 4.

FIG. 11 is a longitudinal sectional view showing a third example of the slit forming method according to claim 4.

FIG. 12 is a longitudinal sectional view of the optical waveguide component.

FIG. 13 is a longitudinal sectional view of an optical waveguide component having slits.

FIG. 14 is a longitudinal sectional view of an optical waveguide component in which a slit has been broken.

[Explanation of symbols]

 10 Si substrate 20 Optical waveguide 21 Inner cladding 22 Optical waveguide core 23 Outer cladding 24 Etching part 25 Projection part 26 Chipping 27 Slit 30 Blade

Claims (6)

[Claims] 1. A slit for inserting an optical component into said core by etching and mechanical cutting in an optical waveguide component having an optical waveguide comprising an inner cladding, an optical waveguide core, and an outer cladding provided on a Si substrate. A method for forming a slit in an optical waveguide component. 2. A method for forming a slit for inserting an optical component into the core of an optical waveguide component provided with an optical waveguide comprising an inner cladding, an optical waveguide core, and an outer cladding on a Si substrate. A method for forming a slit in an optical waveguide component, comprising: forming a groove of a predetermined depth in the outer cladding at a position by etching; and forming a slit by mechanical cutting following the groove. 3. A method for forming a slit for inserting an optical component into a core of an optical waveguide component, comprising: forming a slit on a Si substrate having a projection at a position where the slit is formed; Forming a slit on the optical waveguide component by sequentially providing an outer cladding and mechanically cutting the protrusion along the protrusion provided on the Si substrate. 4. A method of forming a slit for inserting an optical component into a core of an optical waveguide component, comprising: forming a slit on a Si substrate provided with a projection at a position where the slit is formed; An outer cladding is sequentially provided, an etching groove is formed at a predetermined depth from the outer cladding surface along the protrusion provided on the Si substrate, and the groove is formed by mechanically cutting along the groove. Forming a slit in the optical waveguide component. 5. A method for forming a slit in an optical waveguide component, wherein the projection provided on the Si substrate according to claim 3 penetrates the inner cladding. 6. A method for forming a slit in an optical waveguide component, wherein the projection provided on the Si substrate according to claim 4 penetrates the inner cladding.