JPS6381408A - Production of optical waveguide - Google Patents

Abstract

PURPOSE:To obtain an optical waveguide which enables miniaturization, non- adjustment, easy mass production, and cost reduction, by forming a lower clad layer, where a binder is added to fine glass particles, on an insulating substrate and forming a core layer having a different fine glass particle composition on the lower clad layer and forming an upper clad layer on this core layer. CONSTITUTION:A photoconductive paste where a transparent binder is added to fine glass particles obtained by burning the same gaseous raw materials as an optical fiber is printed on an alumina substrate 1 with a prescribed pattern as a thick film, and this film is sintered in a sintering furnace to form a lower clad layer 3. Another photoconductive paste having a different fine glass particle composition is printed on said pattern with a pattern slightly smaller than that of the lower clad layer 3 as a thick film, and this film is sintered in the sintering furnace to form a core layer 4 through which the light passes. The same photoconductive paste as the lower clad layer 3 is printed over the core layer 4 and the lower clad layer 3 as a thick film, and this film is sintered in the sintering furnace to form an upper clad layer 5. Thus, optical parts are miniaturized and mass-produced.

Description

[Detailed description of the invention] (a) Industrial application field This invention has functions such as distributing and combining optical signals, which are basic components for configuring an optical communication system, and
Moreover, the present invention relates to a method of manufacturing an optical waveguide suitable for obtaining an optical hybrid (C) in which electronic circuit elements are directly incorporated and electrical coupling is easy.

(b) Conventional technology In general, in optical communication systems, when transmitting and receiving optical signals,
Light-emitting elements such as semiconductor laser diodes and light-emitting diodes to convert electrical signals into light, optical fibers that guide light,
The basic components are light-receiving elements such as photodiodes and phototransistors that convert light into electrical signals, and bulk components are used in combination with optical components such as prisms and lenses.

(c) Problems to be Solved by the Invention The above-mentioned bulk type optical components are expensive because they use lenses and prisms, which take time to assemble and adjust.
There is also the problem that miniaturization is difficult. In addition, as mentioned above, assembly and adjustment takes time, which leads to poor productivity.
, mass production was difficult.

In view of the above, this invention is compact, requires no adjustment, is easy to mass produce, and
It is an object of the present invention to provide a method for manufacturing an optical waveguide that is essential for constructing an optical vibrator ZC that can realize a low cost.

(d) Means and action for solving the problems The method for manufacturing an optical waveguide of the present invention is to print and bake a first optical waveguide paste made of fine glass particles and a transparent binder on an insulating substrate. A cladding layer is formed, and then a second light guide paste having a different glass particle composition is laminated on the lower clad layer and printed and fired to form a core layer, and the first light guide paste is laminated on the core layer. The upper cladding layer is formed by printing and baking.

In this manufacturing method, optical waveguide pastes for the lower cladding layer, core layer, and upper cladding layer are sequentially printed and fired on an insulating substrate, so optical waveguides of various shapes can be easily formed, and light-emitting elements and light-receiving elements can be formed. It is possible to easily incorporate the following electronic components, and it is also easy to combine with optical fibers, etc., so it is possible to easily realize an optical hybrid (IC) including these electronic components and optical fibers.

(E) Examples The present invention will be explained in more detail with reference to Examples below.

FIG. 2 is a perspective view of an optical waveguide in which the present invention is implemented.

This optical waveguide device includes a Y-branch type optical waveguide 2 formed on an alumina substrate (insulating substrate) 1.

A sectional view taken along line 1-I of this optical waveguide device is shown in the first section.
As shown in the figure.

This optical waveguide 2 is formed as follows.

First, on the alumina substrate 1, a thick film of a light guide paste, which is made by adding a transparent binder to fine glass particles obtained by burning the same gaseous raw material as the optical fiber, is printed in a predetermined pattern and fired in a firing furnace. The first layer, that is, the lower cladding layer 3
form. Furthermore, a thick film of light guiding paste with a different composition of glass particles is printed on the pattern in a pattern slightly smaller than that of the lower cladding layer 3, and is fired in a firing furnace to form the second layer, that is, the core layer 4 through which light passes. do. Subsequently, the core layer 4 and the lower cladding layer 3 are respectively covered, the same light guide paste as the lower cladding layer 3 is printed as a thick film, and the third N, that is, the upper cladding layer 5 is formed by firing in a firing furnace.

Lower craft layer 3 and core layer 4 formed as above
, an optical waveguide 2 is formed by the upper cladding layer 5. When transmitting light within such an optical waveguide 2, the light is confined between the lower cladding layer 3 and the upper cladding layer 5 and propagates within the core layer 4. This example optical waveguide 2
In this case, the thickness of the core layer 4 after firing is about 50 μm, and the thickness of the upper and lower craft layers 3.5 is each about 10 μm.

By this method of this embodiment, that is, by the method of forming the optical waveguide 2 by sequentially laminating the lower cladding layer 3, the core layer 4, and the upper cladding layer 5 on the alumina substrate 1 and printing and firing, optical waveguides of various shapes can be formed. can be manufactured.

FIG. 3 shows an optical waveguide formed using the method of the above embodiment,
FIG. 2 is a perspective view showing an example of an optical hybrid IC incorporating electronic components and the like.

This optical hybrid IC has an IC on an alumina substrate 10.
A chip 13 is bonded to the IC chip 13, and an optical waveguide 11 is also formed on the alumina substrate 10 with the IC chip 13 sandwiched therebetween.
．． 11 is coupled, and a bonding pad 14.14 is formed perpendicular to the optical waveguide 11.11, and the bonding pad 14.14 and the IC chip 13 are connected by bonding wires 15.15, respectively. has been done.

In the optical hybrid IC configured in this way, I
When the light emitting element included in the C chip 13 emits light, an optical signal is transmitted through the optical waveguide 11. Alternatively, if the IC chip 13 includes a light receiving element, the light transmitted through the optical waveguide 11 will be received.

FIG. 4 is a perspective view showing the coupling of the optical waveguide and optical fiber formed by the above manufacturing method, in which an optical waveguide 21 having a branch point is formed on an alumina substrate 20, At this time, at each tip of the optical waveguide 21,
A U-shaped optical fiber guide 22 is formed with the tip end sandwiched therebetween. Then, by inserting the optical fiber 23 into the recessed portion of the optical fiber guide 22 and fixing the optical fiber 23, the optical fiber guide 22, and the optical waveguide 21 with adhesive, the optical waveguide 21 and the optical fiber are connected to each other in advance. Join. Thereby, light can be freely transmitted between each optical fiber through the optical waveguide 21.

FIG. 5 is a perspective view in which three four-wavelength optical waveguides are first formed on an alumina substrate 30, and then an optical waveguide 32 is formed to intersect with the optical waveguide 31.

In this way, by forming the first and second optical waveguides in a cross-layered manner, a high-density optical waveguide circuit can be realized.

6 and 7 show an example of an optical switch constructed using an optical waveguide formed by the above manufacturing method, in which a pair of optical fibers 4 are placed on an alumina substrate 40.
2.43 are arranged at a distance from each other, a hole 44 is provided at the separated point through the alumina substrate 41, and the shielding plate 45 is moved up and down with respect to the hole 44, thereby allowing the optical waveguides 42 to 43 to be separated from each other.
, or vice versa. In this way, the light propagating through the optical waveguide can be changed analogously or digitally by the shielding plate 45, so using this switch,
It becomes possible to manufacture minute displacement gauges, pressure gauges, etc.

(f) Effects of the Invention According to the present invention, an optical waveguide is formed by printing and firing optical guide pastes forming a lower cladding layer, a core layer, and an upper cladding layer, respectively, on an insulating substrate. Optical waveguides of various shapes can be easily constructed on a substrate, and therefore, coupling with excellent connectivity with optical fibers and chips containing electronic components such as light emitting elements and light receiving elements can be freely incorporated. Optical hybrid ICs can be easily manufactured, making it possible to downsize and mass-produce optical components.

In addition, in addition to the optical waveguide, it is possible to directly incorporate electronic circuits such as optical fibers, light-emitting elements, and light-receiving elements to realize the above-mentioned optical hybrid IC, making it possible to obtain optical components with expanded functionality. There are advantages.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view of an optical waveguide manufactured by the manufacturing method of the present invention, FIG. 2 is a perspective view of the optical waveguide, and FIG. 3 is an optical waveguide and an IC formed by the manufacturing method of the present invention. FIG. 4 is a perspective view showing an example of coupling of chips, FIG. 4 is a perspective view showing an example of coupling an optical waveguide and an optical fiber formed by the manufacturing method of the present invention, and FIG. FIG. 6 is a perspective view showing an example of a laminated structure of optical fibers, FIG. 6 is a sectional view showing an example of an optical switch component constructed using an optical waveguide formed by the manufacturing method of the present invention, and FIG. It is a schematic perspective view. 1: Alumina substrate, 2: Optical waveguide, 3: Lower cladding layer, 4: Core layer, 5: Upper cladding layer. Patent applicant: Shimadzu Corporation Agent
Patent Attorney Shigeru Nakamura Figure 1 Figure 2 Figure 4 Figure 5 Figure 6

Claims (1)

[Claims] (1) A first light guide paste made of fine glass particles and a transparent binder is printed and fired on an insulating substrate to form a lower cladding layer, and then laminated on the lower cladding layer to form glass particles with different compositions. A method for manufacturing an optical waveguide, comprising printing and baking a second light guide paste to form a core layer, laminating the core layer on the core layer, and printing and baking the first light guide paste to form an upper cladding layer.