JPH11352345A - Plane optical waveguide device, manufacture thereof, optical transmitter-receiver and manufacture thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make a grating provided with a larger refraction index change amount formable, to provide a wide reflection band and improved wavelength interruption characteristics and make a plane optical waveguide device superior in workability and suitable for integration. SOLUTION: This plane optical waveguide device is provided with first and second couplers 5a and 5b formed by bringing prescribed two parts of two optical waveguides 3a and 3b close to each other. In this case, chirp gratings 4a and 4b for reflecting the optical signals of a prescribed first wavelength made incident by irradiating ultraviolet rays through a chirp grating mask and transmitting the optical signals of a prescribed second wavelength are formed respectively on the two optical waveguides 3a and 3b positioned between the first and second couplers 5a and 5b.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a planar optical waveguide device used in a subscriber wavelength division multiplexing optical transmission system and a method of manufacturing the same, and an optical transmitting / receiving device provided with the above planar optical waveguide device and a method of manufacturing the same. .

[0002]

2. Description of the Related Art There is a wavelength division multiplexing technology as a system for efficiently transmitting a plurality of information through a single optical fiber cable. Wavelength division multiplexing technology is a new multiplexing method in the optical domain, in which a plurality of signals are respectively assigned to optical signals having different wavelengths, a plurality of optical signals are subjected to wavelength division multiplexing (WDM), and one optical fiber cable is used. Is transmitted in both directions. In a wavelength division multiplexing transmission system using this wavelength division multiplexing technology, the transmitter side multiplexes and transmits a plurality of optical signals from light sources having different wavelengths by an optical multiplexer, while the receiver side transmits The light is split into optical signals of the respective wavelengths by the demultiplexer, and is converted into an electric signal by the light receiving element.

[0003] This wavelength division multiplexing transmission system includes:
It has the advantages of (1) transmission of large-capacity information, (2) simultaneous transmission of heterogeneous signals such as digital and analog, and (3) bidirectional transmission over a single optical fiber cable. It is expected as a capacity communication technology. Using this wavelength division multiplexing technology, an optical subscriber cable is laid to each subscriber's home, and an optical subscriber system for bidirectionally communicating large-capacity information such as a video signal is being studied.

[0004] A key technology in this optical subscriber system is called an optical subscriber unit (hereinafter referred to as ONU).
An inexpensive optical transceiver installed at each subscriber's home. O
The NU converts an optical signal transmitted from the station side via the optical fiber cable into an electric signal, converts an electric signal from the subscriber side into an optical signal, and transmits the same to the station side via the optical fiber cable. It is an optical module with functions.

[0005] The ON technology which has been studied so far in the NTT Technical Journal (April 1997, pp. 30-35)
There is a description about an optical module for U. According to this, the optical module has a bidirectional transmission / reception function using an optical signal having a wavelength of 1.3 μm and 1.3 μm and 1.55 μm wavelengths.
Wavelength division multiplexing (WD)
M: Wavelength Division Multiplexing).

In order to achieve these functions, a semiconductor laser diode (hereinafter, referred to as LD) module and a photodiode (Ph) are required.
otoDiode; hereinafter, referred to as PD. 2.) Discrete type optical modules, in which individual components such as modules and optical multiplexers / demultiplexers are connected by optical fiber cables, were initially studied. However, such a method has a problem that it is difficult to reduce the cost because the number of parts is large, the assembly adjustment and inspection steps are many, and the method is complicated. This example is Conventional Example 1 described later.

As an improved technique of the above method, LD
LD and PD sub-modules are mounted on the end face of an optical transceiver with a micro-optics structure in which a PD and a PD are incorporated in one module, and a planar lightwave circuit (PLC) made of quartz (end face mounting). ) Also exist. Here, the micro optics structure refers to a structure of an optical module in which an LD, a PD, a lens, and the like are incorporated in a small case. However, even in these conventional examples, the optical output is monitored using a lens, a spherical lens, or the like, and the method of precisely assembling the optical axis and assembling the optical module (active alignment) requires time and light for adjusting the optical axis. Costly,
It is difficult to reduce costs in terms of mass productivity. An example of the micro-optics structure is Conventional Example 2 described later,
An example in which LD and PD sub-modules are end-mounted on C is Conventional Example 3 described later.

Further, when mounting an LD and a PD on a PLC, there is an optical transceiver for reducing costs by adopting a passive alignment mounting method in which positioning is performed only by using alignment marks without monitoring optical output. I do. In this method, a slit having a thickness of 50 to 100 μm is formed in a quartz PLC, and a dielectric film type WDM filter having a thickness of several tens of μm inserted therein is mounted as an optical multiplexer / demultiplexer. I have. Therefore, to reduce the cost of the optical module of the optical subscriber system, it is not enough to reduce the mounting cost by passive alignment alone, and it is required to reduce the component cost and the mounting cost of the optical multiplexer / demultiplexer. One example of this is Conventional Example 4 described later. For the above reasons,
In optical subscriber transceivers, there is a need for the development of an optical multiplexer / demultiplexer which has a small number of parts, is easy to mount, and has excellent mass productivity.

Further, in recent years, it has been discovered that when an optical fiber cable is irradiated with an excimer laser beam, the refractive index of the core increases when the refractive index of the core is increased. There is also a report that a rate modulation type Bragg grating is formed to produce a narrow band reflection filter. An example of this is Conventional Example 5 described later. However, a WDM filter for an optical transceiver requires a reflection wavelength band of about 10 nm, but a conventional simple Bragg grating can only obtain a reflection wavelength band of about 1 nm. A wide grating characteristic is required. Hereinafter, some more specific conventional examples will be described.

Conventional Example 1. FIG. 24 is a perspective view of an optical transceiver 101 which is a discrete type optical module of Conventional Example 1. In FIG. 24, the optical transceiver 101 includes:
On a printed circuit board 33, a WDM module 30, a multiplexer / demultiplexer 31, an LD module 32, and a PD module 3
And the individual components are connected by optical fiber cables 9da to 9de. An optical signal obtained by wavelength division multiplexing an optical signal of 1.3 μm and an optical signal of 1.5 μm is transmitted from the station side via the optical fiber cable 9db.
The optical signal arriving via the optical fiber cable 9da is
The WDM module 30 separates the optical signal into a 1.3 μm optical signal and a 1.5 μm optical signal. The 1.5 μm optical signal is reflected by the WDM filter 30 and transmitted via the optical fiber cable 9db. Also, 1.
The 3 μm optical signal is transmitted to the demultiplexer 31 via the optical fiber cable 9dc, and is further split into two in the demultiplexer 31, and one optical signal is transmitted to the LD module 32 via the optical fiber cable 9dd. The other optical signal is transmitted to the PD module 34 via the optical fiber cable 9de.
Is transmitted to 1.3 transmitted to PD module 34
The μm optical signal is converted to an electric signal. On the other hand, the electric signal from the subscriber side is transmitted to the LD module 32 at 1.3.
The optical signal is converted to an optical signal of μm, and transmitted to the station via the multiplexer / demultiplexer 31 and the optical fiber cable 9da.

In the configuration of the first conventional example, the cost of each component is high, and since the modules need to be connected using the optical fiber cables 9da to 9de, the mounting cost is high. In order to put the subscriber optical module into practical use, it is necessary to reduce the price of the optical module, and in the first conventional example, it is impossible to reduce the price.

Conventional Example 2. FIG. 25 is a plan view of an optical transceiver 102 having a micro-optics structure according to a second conventional example.
In FIG. 25, the optical transceiver 102 of the second conventional example includes optical fiber cables 9ea to 9ec, a WDM module 35, a half mirror 36, an LD and monitor PD module 37, a reception PD 38, and lenses 56a to 56
c. An optical signal obtained by wavelength division multiplexing a 1.3 μm optical signal and a 1.5 μm optical signal transmitted from the station via the optical fiber cable 9ea is combined with the 1.3 μm optical signal and the 1 μm optical signal in the WDM module 35. It is split into a 0.5 μm optical signal. The demultiplexed 1.5 μm optical signal is transmitted via the optical fiber cable 9eb. On the other hand, the separated 1.3 μm optical signal is transmitted to the optical fiber cable 9.
ec, a half of the light is reflected by the half mirror 36 via the lens 56a, and is received via the lens 56b.
The light is incident on D38, converted into an electric signal, and the other half of the light is transmitted to the LD and monitor PD module 37 via the lens 56c.

The electric signal from the subscriber is converted into an optical signal in the LD and monitor PD module 37,
The optical signal that enters the half mirror 36 via the lens 56c and transmits through the half mirror 36 passes through the lens 56a and the WDM module 35 via the optical fiber cable 9ec.
And transmitted from the WDM module 35 to the station via the optical fiber cable 9ea. In Conventional Example 2, since the lenses 56a to 56c and the half mirror 36 are used, optical axis adjustment is difficult, and mass production is impossible.

Conventional Example 3. FIG. 26 shows the PLC 3 of the conventional example 3.
FIG. 9 shows a plan view of an optical transceiver 103 on which the LD and PD modules 40 are mounted on the end faces. 26, the optical transceiver 103 includes a quartz-based PLC 39 provided with a Mach-Zehnder WDM filter 41 and a Y-branch unit 42, a reception PD 38, and an LD and PD module 40. The PLC 39 has the receiving PD 38 and the LD and PD module 40 mounted on the end faces (that is, end face mounting). The 1.3 μm optical signal and the 1.5 μm optical signal, which are transmitted through the optical fiber cable 9fa from the station side, are subjected to wavelength division multiplexing. It is split into a signal and an optical signal of 1.5 μm. The 1.5 μm optical signal is transmitted via the optical fiber cable 9fc.
The 1.3 μm optical signal is further divided by the Y branch 42 into two.
The signal is transmitted to the receiving PD 38 and converted into an electric signal. The electric signal from the subscriber is converted into an optical signal by the LD and PD module 40, transmitted through the Y branch section 42 via the optical fiber cable 9fb, and further transmitted to the office via the optical fiber cable 9fa.

However, the Mach-Zehnder WDM filter 41 does not sufficiently separate the 1.3 μm optical signal and the 1.5 μm optical signal, and the crosstalk is 10 dB to 2 dB.
Only about 0 dB can be obtained. Since a WDM filter of a subscriber optical module needs a crosstalk of 30 dB or more, it is insufficient as a WDM filter.

Conventional Example 4. FIG. 27 is a perspective view of an optical transceiver 104 using the passive alignment mounting method of Conventional Example 4. The optical transceiver 104 includes optical waveguides 3ca and 3cb on a Si substrate 48 and a dielectric multilayer WDM filter 44, and an LD 45 with spot size conversion, and a waveguide PD 46 on a Si platform 43 of the Si substrate 48. And a monitor PD 47. The LD 45 with spot size conversion, the waveguide type PD 46 and the monitor PD 47 are combined with a quartz P-type by a passive alignment method.
Dielectric multilayer film type WDM filter 4 mounted on LC39
4 is inserted into a groove formed in the PLC 39. A 1.3 μm optical signal and a 1.5 μm wavelength-division multiplexed optical signal transmitted from the station side are converted to 1.3 μm by the dielectric multilayer type WDM filter 44 via the optical waveguide 3ca.
It is split into an optical signal of m and an optical signal of 1.5 μm. 1.3
The optical signal of μm is branched into two by the Y branch part 42 of the optical waveguide 3cb, one of which is a waveguide type P which is a receiving PD.
The light enters D46 and is converted into an electric signal. Further, the electric signal from the subscriber is converted into an optical signal by the LD 45 with spot size conversion, and is converted into a Y-branch portion 4 of the optical waveguide 3cb.
2. Dielectric multilayer WDM filter 44 and optical waveguide 3
It is transmitted to the station side via ca. The dielectric multi-layer film type WDM filter 44 was capable of crosstalk of an optical signal of 1.3 μm and an optical signal of 1.5 μm by 30 dB or more, and was sufficient as a WDM filter.

However, the Si substrate 48 of the PLC 39
A groove for the dielectric multilayer type WDM filter 44 is formed at a constant angle with respect to the optical waveguide 3ca in each of the above, and a dielectric multilayer type WDM filter 44 having a thickness of several tens μm is formed in each of the grooves. Must be inserted and fixed. The mounting method of these dielectric multilayer type WDM filters 44 is complicated, and it is difficult to further reduce the component cost and the mounting cost.

Conventional Example 5 A grating-type optical multiplexer / demultiplexer using light-induced refractive index change is described in the prior art document "OPTNIC
S, Vol. 1, p. 135, 1995, and FIG. 28 is a view showing an optical waveguide device showing a typical grating forming process of the conventional example 5 and its periphery, and FIG. It is sectional drawing which shows a waveguide apparatus and its periphery, (b) is an expanded sectional view of the area | region X of (a),
(C) is an enlarged plan view of a region Y of (a). The optical filter used here is a silica-based optical waveguide type optical filter having a wavelength selectivity by forming an equivalent grating between two couplers of the Mach-Zehnder interferometer.

Referring to FIG. 28 (a), in the grating forming process, a phase mask 50 made of quartz glass is placed on the optical waveguide 51, and a mask 49 made of a material that does not transmit light and having holes in the processed portion is formed. Of the excimer laser beam 2 through the holes 49a of the
Irradiate 9. Referring to FIG. 28B, the phase mask 50 has a relief-shaped diffraction grating formed on the surface thereof.
The relief groove is placed on the optical waveguide 51 so as to be perpendicular to the optical waveguide 51. The excimer laser beam 29 is diffracted by the phase mask 50 and
A −1 order, 0 order, and 1 st order diffraction pattern is formed on 1.
The core 53 of the optical waveguide 51 on which the diffraction pattern is formed
Has an increased refractive index. The irradiation condition of the excimer laser beam 29 was an energy density of 200 mJ / cm ² / pulse, the frequency was 60 Hz, and the irradiation time was 30 minutes. The excimer laser beam 29 is diffracted by the phase grating of the phase mask 50 and is transmitted to the core 53 of the optical waveguide 51 by a −1 order, 0 order.
Next, + 1st order diffraction occurs. The refractive index of the portion where this diffraction occurs changes. FIG. 28C shows that the grating 55 is formed on the core 53.

The silica-based optical waveguide type optical filter comprises a core 53 having a high refractive index for confining light on a silicon substrate.
And an upper clad 5 surrounding the core 53 and having a low refractive index.
2 and a lower cladding 54. Since the silica-based optical waveguide is manufactured using semiconductor technology, it can be miniaturized and integrated, and is suitable for mass-produced products and for manufacturing complex optical filters having a large number of wavelength division multiplexing. FIG. 28B shows a conventional single-mode optical fiber cable.
When an excimer laser beam (wavelength: 248 nm) is irradiated through a phase mask 50 having irregularities at a specific pitch as shown in FIG. 28, a grading 55, which is a Bragg grating corresponding to the pitch of the phase mask 50, becomes a core as shown in FIG. 53 are formed. This was discovered by KO Hill in Canada as a change in light-induced refractive index, and the refractive index of the part irradiated by an excimer laser beam in a color center made by strong light energy was increased. Utilize the phenomenon.

FIG. 29 shows a reflection spectrum by a typical grating of the prior art. The horizontal axis represents the wavelength (nm) of the reflected light, and the vertical axis represents the reflectance (%) of the reflected light.
As is clear from FIG. 29, the grating length is 10 m.
The reflection characteristics of the grating obtained at m were that the Bragg center wavelength was 1530.8 nm and the reflectivity was 8%.
Met. Here, the Bragg center wavelength refers to the wavelength of light when the reflectance of the diffraction grating is maximized.

The Bragg grating formed in the optical fiber cable has excellent characteristics of wavelength blocking characteristics having steep rising and falling, but 0.01 n
It has a very large temperature dependence of m / ° C and a temperature of 50 ° C
, The Bragg center wavelength shifts by about 0.5 nm to the longer wavelength side. The cause of this temperature dependence is that the pitch of the grating of the core changes due to the thermal expansion of the SiO ₂ contained in the cladding and the core of the fiber. In high-density wavelength division multiplexing, the center wavelength interval for each wavelength to be multiplexed is several nm, and cannot be used if a wavelength fluctuation of about 0.5 nm occurs. Therefore, the temperature dependency as it is can be used only for an optical signal having a low multiplexing density.

Also, in the case of the grating type WDM filter, it is difficult to widen the reflection wavelength band, and usually 1n
It is a band from m to 2 nm. However, a bandwidth of 10 nm to 60 nm is desired for a subscriber optical transceiver.

[0024]

As described in the above-mentioned prior art, the prior art WDM multiplexer / demultiplexer having a wavelength-selective reflection function for an optical transceiver is constituted by a dielectric filter. ing. However, there is a drawback that the passage loss is large and many optical components are used, so that it is difficult to assemble and adjust and is not suitable for mass production. Furthermore, the number of components is large, and it is difficult to significantly reduce mounting cost and mass-produce. Further, the fiber grating filter and the optical waveguide grating filter have a narrow reflection band,
There is a problem that it cannot be used as it is for a WDM filter for a subscriber system.

An object of the present invention is to solve the above-mentioned problems, and to provide a planar optical waveguide device having a wavelength-selective reflection function of reflecting only an optical signal of a predetermined wavelength, having a larger refractive index change than the conventional example. A planar optical waveguide device capable of forming a grating having a large amount, having a wide reflection band and improved wavelength blocking characteristics, and suitable for processability and integration, a method of manufacturing the same, and the planar optical waveguide device And a method of manufacturing the same.

[0026]

According to a first aspect of the present invention, there is provided a planar optical waveguide device having a first and a second coupler formed by bringing predetermined two locations of two optical waveguides close to each other. In the optical waveguide device, each of the two optical waveguides located between the first and second couplers is formed by irradiating an ultraviolet ray through a chirp grating mask, and has a predetermined first wavelength that is incident thereon. A chirp grating that reflects an optical signal and transmits an optical signal of a predetermined second wavelength is provided.

The planar optical waveguide device according to the second aspect of the present invention
In a planar optical waveguide device having first and second couplers formed by bringing predetermined two portions of the optical waveguide close to each other, the optical waveguide is added at a germanium addition amount of 20% to 30%. UV light is applied to each of the two optical waveguides formed by subjecting the quartz optical waveguide to high-pressure hydrogen treatment or high-pressure deuterium treatment and positioned between the first and second couplers through a single grating mask. And a single grating that reflects an incident optical signal of a predetermined first wavelength and transmits an optical signal of a predetermined second wavelength.

A planar optical waveguide device according to a third aspect of the present invention
In a planar optical waveguide device having first and second couplers formed by bringing predetermined two locations of two optical waveguides close to each other, two optical waveguides located between the first and second couplers are provided. The wave path is formed in a curved shape, and the two optical waveguides having the curved shape are formed by irradiating ultraviolet rays or X-rays through a single grating mask, respectively, and the incident light of a predetermined first wavelength is formed. A single grating for reflecting a signal and transmitting an optical signal of a predetermined second wavelength is provided.

In the above planar optical waveguide device, the first
By setting the branching ratio when the optical signal having the first wavelength is branched into two in the coupler of the above (1), the coupling length between the two optical waveguides in the second coupler is changed. The branch ratio of the second coupler when the optical signal of the second wavelength is branched into two is set to a predetermined value.

[0030] In the above planar optical waveguide device, ultraviolet rays or X-rays are radiated to the first or second optical waveguide in a straight portion where the grating is not formed between the first and second couplers. Accordingly, the branching ratio of the second coupler when the optical signal of the second wavelength is branched into two is set to a predetermined value.

Further, in the above planar optical waveguide device,
By irradiating the grating with ultraviolet light, a reflection bandwidth and a center wavelength of an optical signal of a first wavelength reflected by the grating are changed and set.

In the planar optical waveguide device, when an optical power meter is connected to one output port of the second coupler and an optical signal is input to one input port of the first coupler. The light intensity of the output port is adjusted to a predetermined value.

Further, in the above planar optical waveguide device,
A port on the first side and two ports on the second side;
One port on the second side is connected to one port of the second coupler, and further includes a Y-branch formed by an optical waveguide, and a part of the optical waveguide of the Y-branch is irradiated with ultraviolet light. Alternatively, the branch ratio of the Y branch portion is changed to a predetermined value by irradiating X-rays.

Still further, in the above-mentioned planar optical waveguide device, the optical waveguide may be made of Si, Ge, P, B, Sn, Ti.
By reacting at least one or more source vapors of the organic alkoxide with ozone gas at a temperature of 600 to 1000 ° C., and forming a film containing the oxide as a main component on a substrate by a CVD method. It is characterized by having.

According to a fourth aspect of the present invention, there is provided a method of manufacturing a planar optical waveguide device, comprising a first optical waveguide and a second optical coupler formed by bringing predetermined two locations of two optical waveguides close to each other. In the manufacturing method, the two optical waveguides located between the first and second couplers are respectively irradiated with ultraviolet rays through a chirp grating mask, so that an optical signal having a predetermined first wavelength is incident. Forming a chirped grating that reflects light and transmits an optical signal of a predetermined second wavelength.

According to a fifth aspect of the present invention, there is provided a method for manufacturing a planar optical waveguide device, comprising a first optical waveguide and a second optical waveguide formed by bringing two predetermined optical waveguides close to each other. In the manufacturing method, the optical waveguide is
Forming a high-pressure hydrogen treatment or a high-pressure deuterium treatment on a quartz optical waveguide doped with germanium in an amount of about 30%, and two optical waveguides located between the first and second couplers. By irradiating each of the wave paths with ultraviolet light through a single grating mask,
Forming a single grating that reflects an incoming optical signal of a predetermined first wavelength and transmits an optical signal of a predetermined second wavelength.

A method of manufacturing a planar optical waveguide device according to a sixth aspect of the present invention is a planar optical waveguide device having first and second couplers formed by bringing predetermined two locations of two optical waveguides close to each other. Forming the two optical waveguides located between the first and second couplers in a curved shape, and applying ultraviolet rays or X-rays to the two optical waveguides having the curved shapes, respectively. Irradiating through a single grating mask to form a single grating that reflects an incoming predetermined first wavelength optical signal and transmits a predetermined second wavelength optical signal. It is characterized by.

Further, in the method for manufacturing a planar optical waveguide device, the step of setting the branching ratio of the first coupler when the optical signal of the first wavelength is branched into two substantially to 1: 1; Changing the coupling length between the two optical waveguides in the second coupler to set the branching ratio of the second coupler when splitting the optical signal of the second wavelength into two, to a predetermined value; Is further included.

Further, in the above-mentioned method for manufacturing a planar optical waveguide device, the first or second optical waveguide in the straight portion where the grating is not formed between the first and second couplers may be irradiated with ultraviolet light or X-ray. The method further includes the step of setting a branching ratio when the optical signal of the second wavelength in the second coupler is bifurcated by irradiating the line with a predetermined value.

Furthermore, in the method of manufacturing a planar optical waveguide device, the grating may be irradiated with ultraviolet light to reduce a reflection bandwidth and a center wavelength of an optical signal of a first wavelength reflected by the grating. The method further includes a step of changing and setting each of them.

In the method of manufacturing a planar optical waveguide device, a step of connecting an optical power meter to one output port of the second coupler, and a step of connecting an optical signal to one input port of the first coupler. And adjusting the light intensity of the output side port to a predetermined value when the light is incident.

Further, in the above-described method for manufacturing a planar optical waveguide device, there is provided a port on the first side and two ports on the second side, and one port on the second side is the second port. Forming a Y-branch formed by an optical waveguide connected to one port of the coupler; and irradiating a part of the optical waveguide of the Y-branch with ultraviolet light or X-rays. And setting the branching ratio to a predetermined value.

Still further, in the above method for manufacturing a planar optical waveguide device, at least one kind of raw material vapor of organic alkoxides of Si, Ge, P, B, Sn and Ti is reacted with ozone gas at a temperature of 600 to 1000 degrees. And CV
The method further comprises forming the optical waveguide by forming a film containing the oxide as a main component on the substrate by using Method D.

The optical transmitting and receiving apparatus according to the seventh invention is characterized in that
A planar optical waveguide device having a branch portion, a light emitting element connected to one terminal on the second side of the Y branch portion, and a light receiving element connected to the other terminal on the second side of the Y branch portion And an element.

According to an eighth aspect of the present invention, there is provided a method for manufacturing a transmitting / receiving device, comprising: The method includes connecting a light emitting element and connecting a light receiving element to the other terminal on the second side of the Y branch.

A method of manufacturing a planar optical waveguide device according to a ninth aspect of the present invention is a method for manufacturing a planar optical waveguide device, comprising the steps of: converting at least one source vapor of organic alkoxides of Si, Ge, P, B, Sn, and Ti and ozone gas at a temperature of 600 to 1000 degrees. Reacting and forming an optical waveguide by forming a film containing the oxide as a main component on the substrate by using a CVD method.

[0047]

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

Embodiment 1 FIG. 1 is a perspective view illustrating a grating-type optical transceiver 1 using an optical waveguide device 2 according to a first embodiment of the present invention. The grating type optical transceiver 1 according to the present embodiment has a cable connection guide groove 10a for connecting the optical fiber cable 9a for transmitting the optical signal from the station side to the subscriber side to the optical waveguide 3a of the optical waveguide device 2. A connection guide groove 10b for connecting an optical fiber cable 9b for transmitting an optical signal from the subscriber side to the station side to the optical waveguide 3b of the optical waveguide device 2, and demultiplexing the wavelength division multiplexed optical signal. , An optical waveguide device 2 for wavelength division multiplexing a plurality of optical signals, a PD 11 for receiving an optical signal from the station side and converting it to an electric signal, And an LD 12 for transmitting to the side.

In the present embodiment, the size of the grating type optical transceiver 1 is preferably 30 to 40 mm in the vertical direction and 5 mm in the horizontal direction. Also,
The optical waveguide device 2 composed of PLC includes two optical waveguides 3a and 3b, chirped gratings 4a and 4b that are refractive index modulation type gratings formed in the two optical waveguides 3a and 3b, and Book optical waveguides 3a, 3b
, Two couplers (or directional couplers) 5a,
5b and the Y branch portion 7 function as an optical waveguide WDM filter.

FIG. 2 is a plan view of the optical waveguide device 2 of FIG. Referring to FIG. 2, the optical waveguide device 2 includes two optical waveguides 3a formed on a substrate 8 mainly composed of quartz, and the two optical waveguides 3a and 3b are both waveguides 3a,
Two couplers 5a and 5b are formed in a portion where 3b is close. The optical waveguide 3a has a linear portion between the two couplers 5a and 5b, and a chirp grating 4a is formed in the linear portion. The starting point of the optical waveguide 3a is port P
1, and its end point is port P3. Further, a portion between the coupler 5a and the chirp grating 4a is defined as a port P11, and the chirp grating 4a and the coupler 5b
The portion between is designated as port P13. The reflectionless terminator 6 is connected to the port P3. Similarly, the optical waveguide 4b is 2
A straight portion is provided between the two couplers 5a and 5b, and a chirped grating 4b is formed in the straight portion.
The starting point of the optical waveguide 3b is defined as a port P2, the two ending points of the optical waveguide 3b branched into two by a Y-branch unit 7 are defined as a port P5 and a port P6, respectively. The portion between the chirped grating 4b and the coupler 5b is referred to as port P12. Further, the optical waveguide 3 in the direction of the port P5 branched by the Y branch portion 7
b is an optical waveguide 3ba, and the optical waveguide 3b in the direction of the port P6 is an optical waveguide 3bb. Further, a portion of the optical waveguide 3b between the coupler 5b and the Y branch 7 is defined as a port P4. The details of the chirp gratings 4a and 4b will be described later.

Next, the optical waveguide device 2 using the flame deposition method
A method of manufacturing the device will be described. FIG. 3 is a block diagram of a film forming apparatus 19 using the flame deposition method used in the method of manufacturing the optical waveguide device 2 of FIG. The film forming apparatus 19 has a film thickness of 1
This is an apparatus for forming a quartz-based optical waveguide film on a substrate made of quartz or the like having a diameter of about 3 mm by a flame deposition method. The film forming apparatus 19 includes (a) a raw material container 13a of silicon tetrachloride, a raw material container 13b of boron trichloride, a raw material container 13c of phosphorus tetrachloride, and a raw material container 13d of germanium tetrachloride; Mass flow controllers 14a to 14d connected to the substrate 13d, and (c) substrates 18a and 18
Rotating turntable 19 on which b and 18c are placed
And a chamber 20 having a torch 16.

As shown in FIG. 3, the source gases used for manufacturing the optical waveguide device 2 are silicon tetrachloride, boron trichloride, phosphorus tetrachloride, and germanium tetrachloride. 13a, a raw material container 13b of boron trichloride, a raw material container 13c of phosphorus tetrachloride, and a raw material container 13d of germanium tetrachloride. Flow controllers 14a to 14d for each of the raw material containers 13a to 13d
Are connected, and the respective gas flow rates can be controlled independently. Therefore, it is possible to transport the four kinds of source gases onto the substrates 8a to 8c at an arbitrary ratio. Each raw material gas is oxidized by an oxyhydrogen flame 17 with an oxyhydrogen mixed gas 15 via a torch 16 to be powdered, and the powder is deposited on the substrates 8a to 8c. The substrates 8a to 8c are mounted on a turntable 18, and the turntable 19 is rotated to make the film thickness uniform.

When manufacturing the optical waveguides 3a and 3b of FIG.
As described above, first, on a quartz substrate 8, silicon tetrachloride,
Boron trichloride, phosphorus tetrachloride, and germanium tetrachloride are supplied to form a quartz film for the cores of the optical waveguides 3a and 3b. The film forming speed is set to about 2 μm / hour and 10 μm
The glass is melted by heat treatment at a temperature of 1100 ° C. so that the glass is melted and a clearing process is performed. As a result, the final thickness of the core film is about 6 μm.

Next, metal chromium is deposited on the core film by sputtering at a film thickness of 5000 °, and a chrome pattern of the Mach-Zehnder type optical waveguide of the optical waveguides 3a and 3b shown in FIG. 1 is formed by photolithography. Then, reactive ion etching (Reactive Ion Etching; hereafter,
This is called the RIE method. 2), the core film on which the metal chromium is not formed is etched to form an optical waveguide core pattern, and the chromium pattern of the Mach-Zehnder type optical waveguides 3a and 3b is completely removed with an acid.

Next, as shown in FIG. 3, silicon tetrachloride, boron trichloride and phosphorus tetrachloride are simultaneously supplied onto the substrate 8 of the optical waveguides 3a and 3b to form cladding portions of the optical waveguides 3a and 3b. A quartz-based film (hereinafter referred to as a cladding film) having a film thickness of 2
Formed at 0 μm. The refractive index of this cladding film was 1.4585, which is close to the refractive index of the quartz substrate. Adjustment of the refractive index of the clad film is performed by adding boron and phosphorus to the quartz film. Here, the addition of boron lowers the refractive index of the cladding film, and the phosphorus increases the refractive index of the cladding film. Further, similarly to the core film, the clad film is subjected to a heat treatment at a high temperature to perform a transparency treatment. The thickness of the clad film after heat treatment is about 20μ
m.

Next, a chip is cut out from the substrate 8 and kept in high-pressure hydrogen or high-pressure deuterium at a temperature of room temperature and 200 atm for about 2 weeks.
Chirp gratings 4a and 4b are formed in the linear portions of the optical waveguides 3a and 3b, respectively. The formation of the chirped gratings 4a and 4b is performed at a wavelength of 2
This is performed by irradiating a 48 nm excimer laser beam to the cores of the optical waveguides 3a and 3b via a chirp grating mask. Irradiation of the excimer laser beam to the cores of the optical waveguides 3a and 3b to which germanium is added increases the refractive index, and chirped gratings 4a and 4b, which are refractive index modulation type gratings, are formed in the cores of the optical waveguides 3a and 3b. .

Here, the chirp grating is one grating in which a plurality of gratings having different pitch intervals are continuously connected, and is referred to as a conventional grating having a single pitch interval (hereinafter, referred to as a simple grating). ), It is possible to broaden the reflection band. The chirp grating mask used in the first embodiment is configured by connecting 24 types of single grating masks having different intervals without gaps. The pitch interval of the single grating mask is increased from 1078 nm by 1 nm to 1101n.
The length of one single grating was 0.5 mm, and the length of one chirped grating was 0.5 mm × 24 = 12 mm, and the amount of change in the refractive index was 0.0017. Using this chirp grating mask, chirp gratings 4a and 4b are formed in the optical waveguides 3a and 3b, respectively.

Next, the flow of processing of an optical signal by the optical waveguide device 2 of the grating type optical transceiver 1 will be described with reference to FIG. The wavelength division multiplexed optical signal obtained by wavelength division multiplexing the 1.3 μm optical signal and the 1.55 μm light transmitted from the station enters the port P1. Port P1
Is split into two linear optical waveguides 3a and 3b by the coupler 5a.
Each of the branched optical signals is converted by the chirp gratings 4a and 4b, for example, into wavelengths 1555-1566.
Only the optical signal of nm is reflected and output from the port P2 again via the coupler 5a. Here, the coupler 5a is optimized so that an optical signal of 1.5 μm is branched at a ratio of Po11: Po12 = 1: 1.
b is optimized so that an optical signal of 1.5 μm is branched at a ratio of Po3: Po4 = 1: 1. here,
Po11 represents the light intensity (or optical power) of the optical signal incident on the port P11 among the optical signals branched from the port P1 by the coupler 5a, and Po12 represents the port P12.
Represents the light intensity (or optical power) of the optical signal incident on the optical signal. Po3 is connected to the coupler 5b from the port P13 or P14.
Represents the optical intensity (or optical power) of the optical signal incident on the port P3 among the optical signals branched into two, and Po4 represents the optical intensity (or optical power) of the optical signal incident on the port P4. In the present embodiment, the coupling length of couplers 5a and 5b is set to 625 μm.

The chirp gratings 4a and 4a
The optical signal in the 1.3 μm band not reflected by b is
The light is directly transmitted through the linear optical waveguides 3a and 3b of the chirped gratings 4a and 4b and transmitted to the ports P3 and P4 via the coupler 5b. The optical signal transmitted to the port P3 is prevented from being reflected by the reflectionless terminator 6. On the other hand, the 1.3 μm optical signal transmitted to the port P4 is split by the Y splitting unit 7 into two optical signals of 50% light intensity or optical power, respectively.
Respectively.

Next, in the grating type optical transmitting / receiving device 1 provided with the optical waveguide device 2, referring to FIG.
The port P1 of the optical waveguide 3a is a cable connection guide groove 10
a connected to the optical fiber cable 9a and the optical waveguide 3
The port P2 of b is connected to the optical fiber cable 9b on the cable connection guide groove 10b. The port P5 is connected to the PD 11, and the port P6 is connected to the LD12. Here, 1.3 μm from the station from port P5
Is output and converted into an electric signal by the PD 11 and passes through an integrated circuit including a frequency conversion and demodulation circuit.
Used by telephone, facsimile and computer. On the other hand, the electric signal from the subscriber is 1.3 by the LD 12.
The optical signal is converted into an optical signal in the μm band and transmitted to the office via the optical waveguide device 2 along the optical fiber cable 9a.

FIG. 4 is a graph showing the relationship between the wavelength of the reflected light and the light intensity, which is the reflection wavelength characteristic of the chirped gratings 4a and 4b of the optical waveguide device 2 of FIG.
A white light source was connected to the port P1 in FIG. 1, white light was made incident from the port P1, and reflected light was measured and evaluated at the port P2. Here, the horizontal axis represents the wavelength (nm) of the reflected light, and the vertical axis represents the relative light intensity (%) of the reflected light. As is clear from FIG. 4, the reflection wavelength band where the light intensity is 95% or more is 1
It was 2.5 nm, which was wider than the conventional example, and satisfied the wavelength band used in the 1.55 μm band of the optical subscriber system.

Therefore, if the grating type optical transmitting / receiving device 1 or the optical waveguide device 2 of the first embodiment is used, the 1.3 μm optical signal transmitted from the station to the subscriber in the optical subscriber system and the 1.5 μm optical signal are transmitted. Wavelength division multiplexed light of an optical signal can be split. The optical waveguide device 2 including the chirped gratings 4a and 4b functioning as an optical waveguide grating type WDM filter can be manufactured by a wafer process.
Therefore, compared to the optical transceiver 104 of the fourth conventional example in which the dielectric multilayer type WDM filter 44 is inserted, the workability is good and suitable for mass production. Further, the grating type optical transceiver 1 including the optical waveguide device 2 can also reduce the number of components, so that the price of the optical transceiver can be significantly reduced.

Although a quartz substrate is used as the substrate 8 in the present embodiment, a silicon substrate may be used as a modification of the first embodiment. However, in that case, it is necessary to form a lower cladding film below the core film. Further, the PD 11 and the LD 12 of the grating type optical transceiver 1 may be discrete components or integrated components. The same applies to the following embodiments.

Embodiment 2 FIG. 5 is a plan view of an optical waveguide device 2A according to a second embodiment of the present invention. In the present embodiment, an optical waveguide device 2 functioning as an optical waveguide WDM filter is manufactured by the same manufacturing method as in the first embodiment.
A is manufactured, and PD11 and LD12 are added to the optical waveguide device 2A.
Grating type optical transceiver 1
A is prepared. Here, the optical waveguide device 2A is different from the optical waveguide device 2 of the first embodiment in that a single grating 4a is used instead of the chirped gratings 4a and 4b.
A and 4bA are formed in the linear portions of the optical waveguides 3a and 3b. Here, a single grating 4
The pitch interval of the single grating mask used when forming the aA and 4bA is 1070 nm, and the single grating 4a formed on the optical waveguides 3a and 3b.
The grating spacing for A and 4bA is 535 nm. The grating length of the single gratings 4aA and 4bA is 10 nm.

In general, the amount of change in the refractive index of a grating is related to the reflection band of the grating. In the conventional technology, a high-pressure hydrogen treatment or a high-pressure deuterium treatment is performed on a quartz-based optical waveguide to which 8% of germanium is added by 500 m.
When the single gratings 4aA and 4bA are manufactured by irradiating an excimer laser beam of J / pulse / cm ² for 60 minutes, the change in the refractive index is about 0.002. The resulting reflection band is about 2 nm.

The amount of change in the refractive index of the core of the optical waveguide is:
It depends on the amount of germanium added in the core, the pressure and time of high-pressure hydrogen treatment or high-pressure deuterium treatment, and the irradiation time and intensity of the excimer laser beam. The reflection band of the formed grating increases as the amount of change in the refractive index increases and the grating length increases, so that a large change in the refractive index and a long grating length are required to obtain broadband reflection characteristics. However, in the case of an optical waveguide created by a wafer process, the grating length is limited,
It is necessary to increase the refractive index change.

Therefore, in the second embodiment, in order to increase the amount of change in the refractive index, the amount of germanium added to the cores of the optical waveguides 3a and 3b is increased to 20 to 30% as compared with 8 to 10% in the prior art. Further, high-pressure hydrogen treatment or high-pressure deuterium treatment is performed at a pressure of 250 to 500 atm with respect to 100 to 200 atm of the prior art, and the treatment period is performed for 3 weeks or more as compared with 1 to 2 weeks of the prior art.

FIG. 6 shows the reflection wavelength characteristics of the single gratings 4aA and 4bA in the optical waveguide device 2A of FIG. 5, and shows the relationship between the wavelength (nm) of the reflected light and the light intensity (%). The formation conditions were as follows: the amount of germanium added to the core was set to 30%, and high-pressure hydrogen treatment or high-pressure deuterium treatment was performed for 2 hours.
The test was performed at 50 atm and a treatment period of 3 weeks. As is apparent from FIG. 6, the reflection band is 12 nm, which satisfies the wavelength band used in the 1.55 μm band of the optical subscriber system. In this case, the amount of change in the refractive index of the single gratings 4aA and 4bA is 0.02, which is 10 times larger than the amount of change in the refractive index of the related art described above. Therefore, Embodiment 2
The optical waveguide device 2A has excellent broadband reflection characteristics.

The method of manufacturing the optical waveguide device 2A is the same as that of the flame deposition method of the first embodiment but also the fifth embodiment described later.
The same effect can be obtained by the above CVD method. However,
In the case of the optical waveguide film formed by the CVD method, since the film has many oxygen defects, the change in the refractive index is further increased as compared with the case where the film is formed by the flame deposition method.

Embodiment 3 FIG. 7 is a plan view of an optical waveguide device 2B according to a third embodiment of the present invention. In the present embodiment, an optical waveguide device 2B functioning as an optical waveguide WDM filter is manufactured by the same manufacturing method as in the first embodiment, and PD11 and L are added to the optical waveguide device 2B.
D12 is further combined to produce the grating type optical transceiver 1B. Optical waveguide device 2B of the present embodiment
Is characterized in that a coupler 5bB is used instead of the coupler 5b of the coupler 5b of the first embodiment. Here, the coupler 5b of the first embodiment transmits a 1.5 μm optical signal to the Po.
Although the coupler 5bB of the present embodiment splits the 1.3 μm optical signal into the Po: 3: Po4 = 1: 1 ratio.
It branches at a ratio of 3: Po4 = 1: 4.

In the first embodiment, the left and right couplers 5
a and 5b both have a bond length of 625 μm,
The branching ratio is Po11: Po12 = 1: 1 for the m optical signal, and is optimized for the reflected light of the 1.5 μm optical signal. The 1.5 μm optical signal incident from the port P1 is reflected by the chirp gratings 4a and 4b, branched again by the coupler 5a, and output from the port P2. FIG. 8 is a comparative example of the third embodiment,
In the case of the first embodiment, when the input optical signal is input from the port P1 with the coupling length of the couplers 5a and 5bB being 625 μm, the chirped grating 4a
And P2 reflected by ports P1 and P2
5 is a graph showing the reflection wavelength characteristics of the reflected light in the 1.55 μm band output from the optical system. As is clear from FIG. 8, the extinction ratio is 26 dB or more in the wavelength band of 1555 to 1565 nm. At this time, the optical signal in the 1.3 μm band incident from the port P1 passes through the chirped gratings 4a and 4b, passes through the coupler 5b, and passes through the port P1.
3 is output. However, the coupler 5b has:
Since the wavelength is different for the transmitted light in the 1.3 μm band, the branching ratio deviates from 1: 1 because of the optimization for the 5 μm optical signal, and the extinction at the port P3 and the port P4. The ratio was as low as 10 dB. The above is the description of the first embodiment.

Also, in the optical waveguide device 2A of the second embodiment, similarly to the optical waveguide device 2 of the first embodiment,
The branching ratio for the 1.3 μm optical signal is Po1 due to the coupler 5a optimized for the 1.5 μm optical signal.
1: Po12 = 1 is shifted from 1: 1.

Therefore, in the present embodiment, this 1.3 μm
The shift of the branching ratio with respect to the optical signal of m is corrected by the coupler 5bB so that the optical signal of 1.3 μm is output almost 100% to the port P4. That is, the coupling length of the coupler 5bB is changed when the optical waveguides 3a and 3b are formed so that an optical signal of 1.3 μm is output almost 100% to the port P4.

FIG. 9 shows the configuration of the coupler 5 according to the third embodiment.
A graph showing the insertion loss of output light output from ports P3 and P4 when a 1.3 μm optical signal is input from port P1 when the coupling length of coupler 5bB is changed with the coupling length of a being 625 μm. It is. As is clear from FIG. 9, when the coupling length of the coupler 5bB is 1825 μm, an extinction ratio of 50 dB or more can be obtained for a 1.3 μm optical signal. That is, an optical signal of 1.3 μm can be output (maximized) to almost 100% at the port P4. The coupling length of the coupler 5bB is 1825 μm.
The optical signal from the port P3 becomes larger regardless of whether it is shorter or longer than m, and the extinction ratio becomes smaller than 20 dB.

FIG. 10 shows that the coupling length of coupler 5a is 625 μm and that of 5bB is 1825 in the third embodiment.
7 is a graph showing transmission wavelength characteristics of 1.3 μm band transmitted light that is transmitted through chirped gratings 4a and 4b and output from ports P3 and P4, respectively, when an input optical signal is input from port P1 and input ports are input from port P1. As is clear from FIG. 10, the transmitted light in the 1.3 μm band
4 and output at port P3 from 1280 to 1335
An extinction ratio of 20 dB is obtained in the wavelength range of
It can be seen that an extinction ratio of 50 dB or more was obtained in the wavelength range of 307 nm. At that time, 1.3 μm at the coupler 5bB
Of the optical signal is Po3: Po4 = 4: 6 to
The branching ratio was about 1: 9. Here, when the port P3 is used as a leak port, it can be leaked by about 10% and monitored.

Therefore, in the third embodiment, when the coupling length of the coupler 5a is 625 μm and the coupling length of the coupler 5bB is 1825 μm, an optical signal of 1.5 μm and 1.
It can be optimized for an optical signal of 3 μm.

As described above, according to the optical waveguide device 2B of the present embodiment, the coupling length of the coupler 5a is changed by 1.5 times reflected by the chirp gratings 4a and 4b.
by optimizing the coupling length of the coupler 5bB to the 1.3 μm optical signal of the transmitted light,
The 1.5 μm optical signal is reflected by the chirp gratings 4 a and 4 b formed between the coupler 5 a and the coupler 5 bB with an improved amount of crosstalk without substantially leaking, and the 1.3 μm optical signal is The 1.3 μm optical signal from the LD 12 can be transmitted without substantially leaking to the PD 11 with the improved crosstalk amount, and can be transmitted to the station side with the improved crosstalk amount without substantially leaking. Can be transmitted.

In the third embodiment, chirped gratings 4a and 4b are used, but the present invention is not limited to this, and a single grating may be used.

Embodiment 4 FIG. 11 is a plan view showing an optical waveguide device 2C according to Embodiment 4 of the present invention. In the present embodiment, an optical waveguide device 2C functioning as an optical waveguide WDM filter is manufactured by the same manufacturing method as in the first embodiment, and PD11 and L are added to the optical waveguide device 2C.
D11 is further combined to produce a grating type optical transceiver 1C. Optical waveguide device 2C of the fourth embodiment
, The port P of the optical waveguide device 2 of the first embodiment
3 is connected to the optical power meter 23 via the optical fiber cable 9c and uses the two couplers 5a and 5b of the optical waveguide device 2;
For a 1.3 μm optical signal, the branching ratio of the coupler 5a deviates from 1: 1. Therefore, in the present embodiment, the deviation of the branching ratio is improved by a method different from that of the third embodiment.

First, an optical signal of 1.3 μm is input from the port P 1 and the optical power meter 23 connected to the port P 3
To monitor the light intensity (or light power) of the optical signal, and to reduce the light intensity from the port P3 to a minimum, the straight line on which either the chirp grating 4a or 4b of the optical waveguide 3a or 3b is not formed. An excimer laser beam having a wavelength of 248 nm (Krf laser light) or a wavelength of 193 nm (Arf laser light) having a diameter of 20 μm is applied to the core portion of the portion of the optical waveguide while changing its position along the longitudinal direction of the optical waveguide of the linear portion. .

When one linear portion of the optical waveguide 3a or 3b is irradiated with an excimer laser beam, the refractive index of the irradiated core portion changes, and the path becomes longer apparently, so that the position between the linear portion and the other optical waveguide is reduced. A phase difference is generated, and the output light intensity of the 1.3 μm optical signal to the port P3 is minimized by laser trimming the output light intensity of the ports P3 and P4, and the output of the 1.3 μm optical signal to the port P4 is reduced. Optimization can be performed to maximize the output, and as a result, the output to the PD 11 can be optimized.

As a modification of the fourth embodiment, instead of excimer laser beam irradiation with ultraviolet light, the wavelength is set to 0.1Å to
X-rays, which are electromagnetic waves of 20 to 30 °, may be irradiated.
In the fourth embodiment, chirped gratings 4a and 4b are used, but the present invention is not limited to this, and a single grating may be used.

Embodiment 5 FIG. 12 is a plan view of an optical waveguide device 2D according to Embodiment 5 of the present invention. In the fifth embodiment, a manufacturing method similar to that of the first embodiment is used.
An optical waveguide device 2D functioning as an optical waveguide type WDM filter is manufactured, and PD11 and LD1 are added to the optical waveguide device 2D.
2 are further combined to produce a grating type optical transceiver 1D. In the optical waveguide device 2D of the present embodiment, the type of the grating is different from that of the optical waveguide device 2B of the third embodiment.
On the other hand, in the optical waveguide device 2D of the present embodiment, the single gratings 4aA and 4bA
Is formed.

In the fifth embodiment, the single grating 4
A part of a or 4b is irradiated with an excimer laser beam having a diameter of 20 μm. Thereby, the single grating 4
The refractive index of aA or 4bB is changed to change the characteristics of the single grating 4aA or 4bB.

First, the reflection wavelength characteristic of the conventional single grating is examined. FIG. 14 shows the reflection wavelength characteristics of a single grating having a length of 20 mm formed using a conventional single-grating mask (pitch interval 1068 nm), and shows the wavelength (nm) of reflected light and the light intensity (%). 7) is a graph showing the relationship of the present embodiment, and is shown as a comparative example with the present embodiment. FIG. 15 is a graph showing the relationship between the amount of change in the refractive index of the conventional single grating and the distance along the longitudinal direction of the single grating. As is clear from FIG. 15, the amount of change in the refractive index at this time is 0.00125.

Next, the reflection wavelength characteristics of the single gratings 4aA and 4bA of the present embodiment will be examined. The single gratings 4aA and 4bA of the optical waveguide device 2D are irradiated with an excimer laser beam at a spot having a diameter of 20 μm. Thereby, the refractive index of the portion where the grating is not originally written also increases. FIG. 13 is a graph showing the reflection wavelength characteristics of the single gratings 4aA and 4bA at this time, showing the relationship between the wavelength (nm) of the reflected light and the light intensity (%). FIG. 16 is a graph showing the relationship between the refractive index variation of the single gratings 4aA and 4bA and the distance along the longitudinal direction of the single gratings 4aA and 4bA at this time.

When FIG. 13 (this embodiment) is compared with FIG. 14 (comparative example), the band is narrower in this embodiment than in the comparative example, and the center wavelength is also shifted to the shorter wavelength side.
However, comparing the out-of-band attenuation, FIG. 13 shows that at a wavelength 1 nm away from the center wavelength
%, And the center wavelength is 1550.
The transmission amount was about 60% at a wavelength 1 nm away from 8 nm. The out-of-band attenuation is a factor that determines the interference between adjacent wavelengths when performing wavelength division multiplexing, and it is preferable that the attenuation be large when the wavelength is 0.5 to 1 nm away from the center wavelength. In other words, several percent is preferable for the amount of passage, and ninety percent for the amount of attenuation. Therefore, it is understood that the optical waveguide device 2D of the present embodiment is effective when performing wavelength division multiplexing.

In the above embodiment, the single gratings 4aA and 4bA are used, but the present invention is not limited to this, and a chirped grating may be used.

Embodiment 6 FIG. FIG. 17 is a block diagram of a film forming apparatus 19a using the CVD method used in the method of manufacturing the optical waveguide device 2 according to the sixth embodiment. The present embodiment is a method of manufacturing the optical waveguide device 2 using a CVD method different from the flame deposition method used in the first embodiment. Here, the film forming apparatus 19a is an apparatus for forming a silica-based optical waveguide film containing SiO ₂ as a main component by a CVD method using ozone oxidation on a silicon substrate having a thickness of about 1 mm. , Flow rate controllers 21a to 21e, raw material containers 22a to 22d, a reaction tube 24 on which a substrate 8d is mounted and provided with an exhaust port 27, and an ozonizer 25 provided with an oxygen gas inlet 26. In this film forming apparatus 19a, four types of CVD material vapors can be simultaneously supplied onto the substrate 8d. The raw materials used are four kinds of alkoxide raw materials, silicon tetraethoxide (Silicon
tetra-ethoxide (Si (OC ₂ H ₅ ) ₄ )), boron tri-propoxide (B (i-OC ₃ H ₇ ) ₃ ), germanium tetra-ethoxide (G
e (OC ₂ H ₅ ) ₄ )) and titanium tripropoxide (Titanium
It is a tri-propoxide (Ti (i- OC 3 H 7) 4)). The carrier gas is a high-purity Ar gas, and flow rate controllers 21a to 21d are connected to the raw material containers 22a to 22d, respectively, so that the flow rates of the respective vapors can be controlled independently. Therefore, the four types of alkoxide raw materials can be mixed in the reaction tube 2 at an arbitrary ratio.
4 can be transported onto the substrate 8d. The reaction tube 24 uses oxygen gas containing 8% ozone introduced through the oxygen gas inlet 26 and partially ozonized by the ozonizer 25 to a temperature of 600 to 1000 degrees, preferably 700 to 800 degrees. The film is formed on the substrate 8d set at 780 degrees by promoting decomposition and reaction of the raw material. As the substrate 8d, a 3-inch diameter silicon substrate is used. The degree of vacuum is 50 Torr, and the film forming speed is about 10 μm / hour.

In manufacturing an optical waveguide, first, only Si (OC ₂ H ₅ ) ₄ and B (i-OC ₃ H ₇ ) ₃ vapors are supplied onto a silicon substrate 8 d to form a quartz film for a lower clad. To form The quartz film for the lower cladding has a temperature of 70 ° C. for the raw material container 22 of Si (OC ₂ H ₅ ) _{4 and} the raw material container 22 b of B (i-OC ₃ H ₇ ) ₃ respectively.
C. and 30.degree. C., and the carrier gas flow rate of each raw material was adjusted to 0.75 l by the flow controllers 21a and 21b.
/ Min and 0.15 l / min while adjusting the substrate 8
A film is formed by decomposing and reacting the raw material transported on d at the above-mentioned substrate temperature. The film formation time is about 2 hours, and the film thickness is about 20 μm.

Next, the raw material container 22a of Si (OC ₂ H ₅ ) ₄ and Ge
(OC ₂ H _{5) 4} and the source container _{22d Si (OC 2 H 5)} 4 and Ge (OC
₂ H ₅ ) ₄ organometallic alkoxide is simultaneously supplied onto the substrate 8 d, and a 6 μm high-refractive-index layer quartz film serving as a core portion of the optical waveguide is formed on the already formed quartz film for the lower clad.
m. The quartz film for this core is made of Si
The temperature of the raw material containers 22a and 22d of (OC ₂ H ₅ ) ₄ and Ge (OC ₂ H ₅ ) ₄ is maintained at 70 ° C. and 30 ° C., respectively, and the carrier gas flow rate of each raw material is controlled by flow controllers 21a and 21c.
The raw material transported onto the quartz film for the lower cladding is adjusted to 0.65 l / min and 0.15 l / min by the decomposition and reaction at the above-mentioned substrate temperature to form a film. However, in the film forming process of the core portion, Ge is used.
The flow rate of the Ge alkoxide vapor is adjusted so that the oxide content becomes about 10%, and the film is formed to a thickness of 6 μm.

Next, a Mach-Zehnder type optical waveguide chrome pattern of the optical waveguides 3a and 3b of FIG. 2 of the first embodiment having an optical waveguide width of 6 μm is formed on the quartz film for the core portion by photolithography. Thereafter, the quartz film for the core portion where the Mach-Zehnder type optical waveguide chrome pattern is not formed is etched by RIE, and then the Mach-Zehnder type optical waveguide chrome pattern is completely removed with an acid.

Next, a quartz film having a thickness of about 20 μm serving as an upper clad is formed on Si (OC ₂ H ₅ ) ₄ , B (i-OC ₃ H ₇ ) ₃ and Ti (i-OC ₃ H).
₇₎ the ₄ ingredients vapor Si (OC ₂ H _{5) 4} of the raw material container 22a, B (i-OC ₃
H ₇ ) ₃ raw material container 22 b and Ti (i-OC ₃ H ₇ ) ₄ raw material container 22
c to form a film on the clad quartz film and the core. The conditions for the CVD film formation at this time are the same as those for the lower clad film formation.

As in the method of manufacturing the waveguide device 2 of the first embodiment, the manufactured optical waveguide device 2 is subjected to a high-pressure hydrogen treatment or a high-pressure deuterium treatment at room temperature at 150 atm for 2 weeks.
Immediately thereafter, strong ultraviolet rays (excimer laser beam, Krf: wavelength 248 nm) are irradiated to the linear portions of the optical waveguides 3a and 3b through a chirp grating mask, and the core portions of the linear portions of the optical waveguides 3a and 3b are irradiated. Chirp gratings 4a and 4b, which are refractive index modulation type gratings induced by light, are formed. Irradiation conditions are
The laser body has an energy density of 500 mJ / cm ² / pulse, a frequency of 60 Hz, and an irradiation time of 60 minutes. When the refractive index change after excimer laser beam irradiation is measured,
0.002.

The reflection wavelength characteristics obtained by the chirp gratings 4a and 4b formed as described above are as follows.
As in the first embodiment, the bandwidth is 14 nm, and the wavelength is 155.
The optical signal of 3 to 1567 nm was almost 100% reflected. The insertion loss from the port P1 to the port P2 is about 2 dB for a 1.5 μm optical signal, and the insertion loss from the port P1 to the port P4 is 4.5 for an 1.3 μm optical signal.
dB. The change in the refractive index is larger than that of the optical waveguide formed by the flame deposition method, and the chirp gratings 4a and 4
The reflection wavelength band due to b became wide.

Here, differences between the conventional CVD method and the CVD method used in the present embodiment will be described. Prior art CVD by ozone oxidation using organic alkoxide raw material
When a quartz-based film is formed by the method, the film is formed at a low temperature of 300 to 400 degrees, and then heat-treated at 600 to 1000 degrees. In this method, at a substrate temperature of 300 to 400 ° C., organic substances and the like in the organic alkoxide raw material are not completely removed but remain, and the reliability of the quartz film is reduced, and the refractive index of the film is deviated from that of the bulk. There have been problems such as making the refractive index distribution of the film non-uniform. These problems cannot be completely eliminated by heat treatment later. In the fifth embodiment according to the present invention, the organic material remaining in the film is reduced by setting the substrate temperature at the time of film formation to 600 ° C. or higher, and the film is completely filled even in a narrow gap.

The mechanism of film formation is different from the conventional CVD method using ozone oxidation. FIG. 18 is a graph showing the relationship between the film forming speed by the CVD method and the substrate temperature. In the conventional CVD method using ozone oxidation, a quartz film is deposited on a substrate by oxidizing organic alkoxide with ozone at a low temperature at which ozone gas of 300 to 400 degrees is not decomposed. On the other hand, in this embodiment, as can be seen from FIG. 18, as the substrate temperature is further increased, the deposition rate of the quartz film becomes extremely slow from 450 degrees. This is because ozone is decomposed at a high temperature and the oxidizing power is reduced. Thereafter, when the substrate temperature is further increased, a quartz film can be formed again from around 600 degrees. Therefore, it is considered that the organic alkoxide is partially decomposed by the decomposed ozone to form an intermediate, which is finally decomposed by heat energy of 600 ° C. or more, and is deposited as a quartz film on the substrate.

In the above embodiment, Si, G
Although the quartz film is formed using organic alkoxides of e, B, and Ti, the present invention is not limited to this, and the quartz film may be formed using organic alkoxides of P and Sn.

As described above, by forming the optical waveguide using the new CVD method used in the present embodiment, a grating having a large refractive index change can be formed, and the reflected light of the grating can be reduced. The reflection bandwidth can be widened. The CV according to the present embodiment
It is also possible to manufacture the grating type optical transceiver 1 by combining the optical waveguide device 2 manufactured by the method D with the PD 11 and the LD 12.

Further, according to the present embodiment, the process can be simplified and the manufacturing cost can be greatly reduced as compared with the conventional method for manufacturing a planar optical waveguide device. Also,
Since the function of wavelength division multiplexing can be realized by using the above-mentioned grating by the wafer process, for example, a planar optical waveguide device can be manufactured at lower cost than the conventional example.

Embodiment 7 FIG. In the present embodiment, an optical power meter 23 is monitored using an optical waveguide device 2C and a grating type optical transmitting / receiving device 1C similar to those of the fourth embodiment, and one of the chirp gratings 4a and 4b or an optical waveguide in the vicinity thereof is monitored. By irradiating one of the wave paths 3a and 3b with ultraviolet light, an optical waveguide device 2C that obtains an optimum optical output is manufactured. That is, by performing an ultraviolet irradiation process on one of the optical waveguides 3a and 3b of the optical waveguide device 2C, 1.
An optical waveguide device 2C that minimizes the light intensity of the optical signal of 3 μm and maximizes the light intensity to the port P4 is manufactured.

In the optical waveguide device of the present embodiment, first, a wavelength division multiplexed light of a 1.3 μm optical signal and a 1.5 μm optical signal is input from a port P1. The wavelength division multiplexed optical signal is split by the couplers 5a and 5b into two optical waveguides 3a and 3b.
Only the optical signal having a wavelength of 1554 to 1566 nm is reflected by a and 4b, and the reflected light is output from the port P2 again via the coupler 5a. Chirp grating 4
The 1.3 μm optical signals transmitted through a and 4b are output from ports P3 and P4 via couplers 5b via ports P13 and P14 as they are. The optical signal to the port P3 is monitored by the optical power meter 23, and the optical signal to the port P4 is sent to the optical waveguide 3ba by the Y branching unit 7.
The optical signal is branched into two optical signals at a 50% intensity into the port P5 via the optical waveguide 3bb and the port P6 via the optical waveguide 3bb, and is output from the ports P5 and P6.

The output power monitoring optical power meter 23 is monitored to adjust the wavelength characteristic or the optical phase difference by irradiating the grating 4a or 4b or the optical waveguide 3a or 3b with ultraviolet rays as described in the fifth and sixth embodiments. I do. By monitoring the light intensity from the port P3 so as to be minimum and setting the irradiation amount of the ultraviolet light, the port P3 is monitored.
4 gave the maximum light output. By this, 1.3 μm
The insertion loss of the optical signal into the port P4 can be reduced, and the yield of the optical waveguide device as a product can be improved.

Embodiment 8 FIG. FIG. 19 is a plan view of an optical waveguide device 2E according to the eighth embodiment of the present invention. In the present embodiment, an optical waveguide device 2E is manufactured by the method for manufacturing the optical waveguide device 2 using the CVD method of the sixth embodiment, and a PD11 and an LD12 are further combined with the optical waveguide device 2E to form a grating type optical transceiver. Fabricate 1E. In the present embodiment, when the optical waveguide chrome pattern is processed with chromium metal by the CVD method, an optical waveguide pattern having a curved portion as shown in FIG. 19 is used instead of the optical waveguide pattern shown in FIG. Using the optical waveguide pattern having this curved portion, optical waveguides 3a and 3b are produced in the same manner as in the sixth embodiment, and a single grating 4aE and 4bE is formed.
The curved portions of the optical waveguides 3a and 3b are particularly
aE and 3bE.

FIG. 20 is an enlarged view of the single grating 4aE in the curved optical waveguide 3aE. Referring to FIG. 20, a curved grating 3aE has a single grating 4a.
When E is formed, the length of the optical waveguide separated by the leftmost grating and the right grating in the single grating 4aE and the length of the optical waveguide separated by the rightmost grating and the left grating are different. Not identical, the length of the left optical waveguide is slightly shorter than the length of the right optical waveguide. Therefore,
Apparently, the grating interval of the single grating 4aE changes, thereby changing the entire band of the reflection wavelength characteristic. For example, a single grating 4a is formed by a single grating mask having a single pitch interval of 1068 nm.
When E was formed, a grating having a grating interval of 534 nm to 544 nm could be formed in the curved optical waveguide 3aE. The following table shows the relationship between the angle θ and the shift amount of the Bragg center wavelength. Where the angle θ
Is the angle between the perpendicular to the curved optical waveguide 3aE and the leftmost grating of the single grating 4aE.

[0106]

[Table 1]

As can be seen from Table 1, the shift amount of the Bragg center wavelength increases as the angle θ increases.

FIG. 21 is a graph showing a reflection wavelength characteristic by a single grating formed on a straight line portion of a conventional optical waveguide, which is shown as a comparative example with the present embodiment, and FIG. 22 is a curve of the present embodiment. It is a graph showing the reflection wavelength characteristic by single gratings 4aE and 4bE formed in optical waveguides 3aE and 3bE. The hatching in FIGS. 21 and 22 represents side lobes that change above and below the hatching. Referring to FIG. 21 of the prior art,
The reflection wavelength characteristic of the reflected light by the single grating formed on the linear optical waveguide was a reflection bandwidth of 3.5 nm and a center wavelength of 1553.5 nm.
, The characteristics of the light reflected by the single gratings 4aE and 4bE formed in the curved optical waveguides 3aE and 3bE have a reflection bandwidth of 4.5 nm and a center wavelength of 1552.5.
nm. From this, the single gratings 4aE and 4b formed on the curved optical waveguides 3aE and 3bE
It was found that E increased the reflection bandwidth, shifted the center wavelength, and achieved the same effect as the chirped grating.

As a modification of the eighth embodiment, the center wavelength adjustment processing in the fourth or fifth embodiment may be further performed. That is, the curved waveguide 3 of the optical waveguide device 2E
By irradiating aE or 3bE, or the single grating 4aE or 4bE with ultraviolet light, the reflection characteristics and transmission characteristics of the optical waveguide device 2E can be adjusted.
Here, it should be noted that only the portions forming the single gratings 4aE and 4bE need be curved patterns, and the other portions of the curved optical waveguides 3aE and 3bE may be either straight lines or curved lines. When forming the single gratings 4aE and 4bE, not only ultraviolet rays but also electromagnetic waves such as X-rays may be used.

Embodiment 9 FIG. FIG. 23 shows an optical waveguide device 2
5 shows an enlarged view of the Y branch portion 7 of the optical waveguide 3b in FIG. In the present embodiment, the branching ratio of the Y-branch unit 7 of the grating type optical transmitting / receiving device 1 of the first embodiment is changed by irradiating the excimer laser beam 29 to the core of the optical waveguide 3a of the Y-branch unit 7. It is characterized by the following.

In FIG. 23, the port P of the optical waveguide 3a
The optical signal input from 4 is branched by the Y branching unit 7 into a port P5 of the optical waveguide 3ba and a port P6 of the optical waveguide 3bb. When the Y branch portion 7 has a symmetric shape, the light intensity can be branched to Po5: Po6 = 1: 1 without wavelength dependence. Here, Po5 and Po6 represent the optical intensities of the optical signals output from the port P4 to the ports P6 and P6, respectively.

Here, for example, in the case of an asymmetric shape due to a manufacturing error, it is considered that the branching ratio is different. Therefore, an excimer laser beam 2 having a diameter of several μm to several tens μm is used.
By irradiating 9 to the branch portion of the Y branch portion 7 and increasing the refractive index of the irradiated portion, the branch ratio of the Y branch portion 7 can be adjusted.

Here, the intensity of the laser beam used for ultraviolet irradiation is set to 400 mJ / pulse / cm ² , and the irradiation time is set to about 5 minutes per one place. Before irradiation with the excimer laser beam 29, high-pressure deuterium or deuterium treatment at 150 atm is performed for 7 days to increase the change in refractive index.

Before and after the excimer laser beam irradiation, the branch ratio of the Y branch portion 7 changed from Po5: Po6 = 4: 6 to 5: 5. The reverse is also possible depending on the ultraviolet irradiation position. In the present embodiment, Po5: Po6 = 1:
Although adjusted to a branching ratio of 1, it is not necessary exactly. P
By the combination of D11 and LD12, if the PD11 has high reception sensitivity and the LD12 has low power, it is possible to increase the branching ratio to the LD12 side and vice versa. .

As described above, according to the ninth embodiment, the Y branch portion 7 of the optical waveguide 3b in the optical waveguide device 2 is used.
Can be set by changing the branching ratio of the optical waveguide device 2 to a predetermined value. For example, even if there is a deviation from 1: 1, the deviation can be corrected. It can be improved in comparison.

In this embodiment, the ultraviolet irradiation process is performed using the optical waveguide device 2. However, the other optical waveguide devices described above may be used. If it is a wave path, this processing is effective. Further, electromagnetic waves such as X-rays may be used instead of ultraviolet rays.

[0117]

As described above in detail, according to the planar optical waveguide device of the first invention, the predetermined two of the two optical waveguides are used.
In the planar optical waveguide device including the first and second couplers formed by bringing the portions close to each other, the first and second couplers may be used.
Are formed by irradiating the two optical waveguides located between the couplers with ultraviolet rays through a chirp grating mask, reflect an incident optical signal of a predetermined first wavelength, and reflect a predetermined second optical signal. A chirp grating that transmits an optical signal having a wavelength is provided. Therefore, it is possible to form a chirped grating having a large change in the refractive index as compared with the conventional example, thereby making it possible to increase the reflection bandwidth of the optical signal of the first wavelength as compared with the conventional example.
Further, since the function of wavelength division multiplexing can be realized by the wafer process, a planar optical waveguide device can be manufactured at lower cost than in the conventional example.

Further, according to the planar optical waveguide device of the second invention, the planar optical waveguide including the first and second couplers formed by bringing predetermined two locations of the two optical waveguides close to each other. In the device, the optical waveguide is 20% to 30%.
% Of the germanium optical waveguide doped with germanium is formed by high-pressure hydrogen treatment or high-pressure deuterium treatment, and the two optical waveguides located between the first and second couplers are respectively A single grating formed by irradiating ultraviolet rays through a single grating mask reflects an incident optical signal of a predetermined first wavelength and transmits an optical signal of a predetermined second wavelength. Therefore, it is possible to form a single grating having a large change in the refractive index as compared with the conventional example, whereby the reflection bandwidth of the optical signal of the first wavelength can be widened as compared with the conventional example. Further, since the function of wavelength division multiplexing can be realized by the wafer process, a planar optical waveguide device can be manufactured at lower cost than in the conventional example.

Further, according to the planar optical waveguide device of the third invention, the planar optical waveguide having the first and second couplers formed by bringing predetermined two locations of the two optical waveguides close to each other. In the apparatus, two optical waveguides located between the first and second couplers are formed in a curved shape, and ultraviolet rays or X-rays are respectively applied to the two optical waveguides having the curved shape by a single grating mask. And a single grating that reflects an incident optical signal of a predetermined first wavelength and transmits an optical signal of a predetermined second wavelength. Therefore, it is possible to form a single grating having a large change in the refractive index as compared with the conventional example, whereby the reflection bandwidth of the optical signal of the first wavelength can be widened as compared with the conventional example. Further, since the function of wavelength division multiplexing can be realized by the wafer process, a planar optical waveguide device can be manufactured at lower cost than in the conventional example.

In the above planar optical waveguide device, the first
By setting the branching ratio when the optical signal of the first wavelength is split into two in the coupler of FIG. 1 to substantially 1: 1 and changing the coupling length between the two optical waveguides in the second coupler, The branching ratio of the second coupler when the optical signal of the second wavelength is branched into two can be set to a predetermined value. Therefore, for example, by maximizing the optical signal of the second wavelength output from the second coupler and applying this to the optical transmission / reception device of the ONU, a device with optimized optical demultiplexing performance is realized. it can.

In the above planar optical waveguide device, ultraviolet rays or X-rays are radiated to the first or second optical waveguide in a straight portion where the grating is not formed between the first and second couplers. By doing so, it is possible to set the branching ratio when the optical signal of the second wavelength is branched into two in the second coupler to a predetermined value. Therefore,
For example, by maximizing the optical signal of the second wavelength output from the second coupler and applying this to the ONU optical transmission / reception apparatus, an apparatus with optimized optical demultiplexing performance can be realized.

Further, in the above planar optical waveguide device,
By irradiating the grating with ultraviolet light, the reflection bandwidth and the center wavelength of the optical signal of the first wavelength reflected by the grating can be changed and set. Therefore, for example, by maximizing the optical signal of the second wavelength output from the second coupler and applying this to the optical transmission / reception device of the ONU, a device with optimized optical demultiplexing performance is realized. it can.

In the above planar optical waveguide device, when an optical power meter is connected to one output port of the second coupler and an optical signal is input to one input port of the first coupler. The light intensity at the output side port can be adjusted to a predetermined value. Therefore, for example, by maximizing the optical signal of the second wavelength output from the second coupler and applying this to the optical transmission / reception device of the ONU, a device with optimized optical demultiplexing performance is realized. it can.

Further, in the above planar optical waveguide device,
A port on the first side and two ports on the second side;
One port on the second side is connected to one port of the second coupler, and further includes a Y-branch formed by an optical waveguide, and a part of the optical waveguide of the Y-branch is irradiated with ultraviolet light. Alternatively, by irradiating X-rays, the branching ratio of the Y-branch can be changed to a predetermined value. Therefore, for example, by optimizing the level of an optical signal input / output to / from the Y-branch unit and applying this to an optical transmission / reception apparatus of an ONU, an apparatus with optimized optical demultiplexing performance can be realized. .

Further, in the above planar optical waveguide device, the optical waveguide is formed of Si, Ge, P, B, Sn, Ti.
By reacting at least one or more raw material vapors of the organic alkoxide with ozone gas at a temperature of 600 to 1000 ° C., and forming a film mainly containing the oxide on a substrate by a CVD method. You. Therefore, it is possible to form a grating having a large change in the refractive index as compared with the conventional example, thereby making it possible to increase the reflection bandwidth of the optical signal of the first wavelength as compared with the conventional example. Further, since the function of wavelength division multiplexing can be realized by the wafer process, a planar optical waveguide device can be manufactured at lower cost than in the conventional example.

According to the method of manufacturing a planar optical waveguide device according to the fourth invention, a planar optical waveguide having first and second couplers formed by bringing two predetermined positions of two optical waveguides close to each other. In the method of manufacturing a waveguide device, the two optical waveguides located between the first and second couplers are irradiated with ultraviolet rays through a chirp grating mask, respectively, so that a predetermined first wavelength of the incident light is emitted. Forming a chirped grating that reflects the optical signal and transmits the optical signal of the predetermined second wavelength. Therefore, it is possible to form a chirped grating having a large change in the refractive index as compared with the conventional example, thereby making it possible to increase the reflection bandwidth of the optical signal of the first wavelength as compared with the conventional example. Further, since the function of wavelength division multiplexing can be realized by the wafer process, a planar optical waveguide device can be manufactured at lower cost than in the conventional example.

According to the method of manufacturing the planar optical waveguide device according to the fifth aspect of the present invention, the planar optical waveguide having the first and second couplers formed by bringing two predetermined positions of two optical waveguides close to each other. In the method for manufacturing a waveguide device, the optical waveguide is
Forming high-pressure hydrogen treatment or high-pressure deuterium treatment on a quartz optical waveguide doped with germanium in an amount of 20% to 30%; and two optical waveguides positioned between the first and second couplers. Irradiating each of the optical waveguides with ultraviolet rays through a single grating mask, thereby reflecting an incident optical signal of a predetermined first wavelength and transmitting an optical signal of a predetermined second wavelength. Forming a. Therefore, it is possible to form a single grating having a large change in the refractive index as compared with the conventional example, whereby the reflection bandwidth of the optical signal of the first wavelength can be widened as compared with the conventional example. Further, since the function of wavelength division multiplexing can be realized by the wafer process, a planar optical waveguide device can be manufactured at lower cost than in the conventional example.

According to the method of manufacturing the planar optical waveguide device of the sixth invention, the planar optical waveguide having the first and second couplers formed by bringing two predetermined positions of two optical waveguides close to each other. In the method of manufacturing a waveguide device, a step of forming two optical waveguides located between the first and second couplers in a curved shape, and forming the two optical waveguides having the curved shape with ultraviolet rays or X rays, respectively. By irradiating the line through a single grating mask, a predetermined first
Forming a single grating that reflects the optical signal of the predetermined wavelength and transmits the optical signal of the predetermined second wavelength. Therefore, it is possible to form a single grating having a large change in the refractive index as compared with the conventional example.
The reflection bandwidth of the optical signal of the first wavelength can be made wider than that of the conventional example. Further, since the function of wavelength division multiplexing can be realized by the wafer process, a planar optical waveguide device can be manufactured at lower cost than in the conventional example.

Further, in the method for manufacturing a planar optical waveguide device, the step of setting the branching ratio when the optical signal of the first wavelength is branched into two in the first coupler is substantially 1: 1; Changing the coupling length between the two optical waveguides in the second coupler to set a branching ratio of the second coupler when the optical signal of the second wavelength is branched into two, to a predetermined value; Further included. Therefore,
For example, by maximizing the optical signal of the second wavelength output from the second coupler and applying this to the ONU optical transmission / reception apparatus, an apparatus with optimized optical demultiplexing performance can be realized.

Further, in the method of manufacturing a planar optical waveguide device, the linear or linear portion of the first or second optical waveguide where the grating is not formed between the first and second couplers may be exposed to ultraviolet rays or X-rays. The method further includes a step of setting a branching ratio when the optical signal of the second wavelength in the second coupler is branched into two by irradiating the line with a predetermined value. Therefore, for example, the optical signal of the second wavelength output from the second coupler is maximized, and this is turned on.
By applying to the U optical transmission / reception apparatus, an apparatus with optimized optical demultiplexing performance can be realized.

Further, in the method of manufacturing a planar optical waveguide device, the grating may be irradiated with ultraviolet light to reduce a reflection bandwidth and a center wavelength of an optical signal of a first wavelength reflected by the grating. The method further includes a step of changing and setting each. Therefore, for example, by maximizing the optical signal of the second wavelength output from the second coupler and applying this to the optical transmission / reception device of the ONU, a device with optimized optical demultiplexing performance is realized. it can.

In the above method for manufacturing a planar optical waveguide device, a step of connecting an optical power meter to one output port of the second coupler, and a step of connecting an optical signal to one input port of the first coupler. And adjusting the light intensity of the output side port to a predetermined value when the light is incident. Therefore, for example, by maximizing the optical signal of the second wavelength output from the second coupler and applying this to the optical transmission / reception device of the ONU, a device with optimized optical demultiplexing performance is realized. it can.

Further, in the method for manufacturing a planar optical waveguide device, the planar optical waveguide device may include a first port and two ports on a second side, and one of the ports on the second side. Is connected to one port of the second coupler to form a Y-branch formed by an optical waveguide, and irradiates a part of the optical waveguide of the Y-branch with ultraviolet rays or X-rays. And changing the branching ratio of the Y-branch to a predetermined value. Therefore, for example, by optimizing the level of an optical signal input / output to / from the Y-branch unit and applying this to an optical transmission / reception apparatus of an ONU, an apparatus with optimized optical demultiplexing performance can be realized. .

Further, in the method of manufacturing a planar optical waveguide device, at least one kind of raw material vapor of organic alkoxides of Si, Ge, P, B, Sn, and Ti is reacted with ozone gas at a temperature of 600 to 1000 degrees. And CV
The method further includes forming the optical waveguide by forming a film containing the oxide as a main component on the substrate by using Method D. Therefore, it is possible to form a grating having a large change in the refractive index as compared with the conventional example, thereby making it possible to increase the reflection bandwidth of the optical signal of the first wavelength as compared with the conventional example. Further, since the function of wavelength division multiplexing can be realized by the wafer process, a planar optical waveguide device can be manufactured at lower cost than in the conventional example.

According to the optical transmission / reception device of the seventh invention,
A planar optical waveguide device having the Y branch, a light emitting element connected to one terminal on the second side of the Y branch, and a light emitting element connected to the other terminal on the second side of the Y branch; Light receiving element. Therefore, it is possible to provide an optical transmitting and receiving device including a planar optical waveguide device having a wider reflection bandwidth for an optical signal of the first wavelength than the conventional example. In addition, since the function of wavelength division multiplexing can be realized by the wafer process, an optical transmitting / receiving device can be manufactured at a lower cost than the conventional example.

According to the method of manufacturing the transmission / reception device according to the eighth invention, each step of the method of manufacturing the planar optical waveguide device having the Y-branch unit, and one terminal on the second side of the Y-branch unit And a step of connecting a light receiving element to the other terminal on the second side of the Y branch section. Therefore, it is possible to provide an optical transmitting and receiving device including a planar optical waveguide device having a wider reflection bandwidth for an optical signal of the first wavelength than the conventional example. In addition, since the function of wavelength division multiplexing can be realized by the wafer process, an optical transmitting / receiving device can be manufactured at a lower cost than the conventional example.

According to the method of manufacturing the planar optical waveguide device according to the ninth aspect, the raw material vapor of at least one of organic alkoxides of Si, Ge, P, B, Sn, and Ti and the ozone gas are heated to a temperature of 600 to 1000. React at the degree, CV
Forming an optical waveguide by forming a film containing the oxide as a main component on a substrate by using Method D. Therefore, the process can be simplified and the manufacturing cost can be significantly reduced as compared with the conventional method for manufacturing a planar optical waveguide device. Further, for example, when a grating is formed on the optical waveguide, it is possible to form a grating having a large change in the refractive index as compared with the conventional example.
Further, the function of wavelength division multiplexing can be realized by using the above-mentioned grating, for example, by the wafer process, so that a lower-cost planar optical waveguide device can be manufactured as compared with the conventional example.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a configuration of a grating type optical transceiver 1 including an optical waveguide device 2 according to a first embodiment of the present invention.

FIG. 2 is a plan view of the optical waveguide device 2 of FIG.

FIG. 3 is a block diagram of a film forming apparatus 19 using a flame deposition method used in the method of manufacturing the optical waveguide device 2 of FIG.

4 is a graph showing a reflection wavelength characteristic of the chirped gratings 4a and 4b of the optical waveguide device 2 of FIG. 2, and showing a relationship between a light intensity of reflected light and a wavelength.

FIG. 5 is a plan view of an optical waveguide device 2A according to a second embodiment of the present invention.

6 is a graph showing the reflection wavelength characteristics of the single gratings 4aA and 4bA in the optical waveguide device 2A of FIG. 5, showing the relationship between the light intensity of reflected light and the wavelength.

FIG. 7 is a plan view of an optical waveguide device 2B according to a third embodiment of the present invention.

FIG. 8 is a comparative example of the third embodiment,
In the optical waveguide device 2 shown in FIG. 2, when an input optical signal is incident from the port P1, it is reflected by the chirped gratings 4a and 4b, and then the port P1 and the port P
3 is a graph showing the reflection wavelength characteristics of the reflected light in the 1.55 μm band output from each of FIGS.

FIG. 9 is a sectional view of the optical waveguide device 2B of FIG.
7 is a graph showing transmission wavelength characteristics of 1.3 μm band transmitted light output from ports P3 and P4 after passing through chirped gratings 4a and 4b when an input optical signal is input from FIG.

FIG. 10 shows a configuration in which the coupling length of the coupler 5a is 625 μm and the coupling length of 5bB is 18 in the optical waveguide device 2B of FIG.
When an input optical signal is input from the port P1, the light passes through the chirped gratings 4a and 4b, and then is output from the ports P3 and P4.
5 is a graph showing transmission wavelength characteristics of transmitted light in the μm band.

FIG. 11 is a plan view of an optical waveguide device 2C according to a fourth embodiment of the present invention.

FIG. 12 is a plan view of an optical waveguide device 2D according to a fifth preferred embodiment of the present invention.

13 is a graph showing the reflection wavelength characteristics of the single gratings 4aA and 4bA irradiated with ultraviolet rays in the optical waveguide device 2D of FIG. 12, and showing the relationship between the wavelength of reflected light and the light intensity.

14 is a graph showing the relationship between the wavelength of reflected light and the light intensity, which is a reflection wavelength characteristic of a conventional single-grating in a comparative example of the optical waveguide device 2D of FIG.

FIG. 15 shows a change in the refractive index of a conventional single grating in a comparative example of the optical waveguide device 2D of FIG.
It is a graph which shows the relationship of the distance along the longitudinal direction of the single grating concerned.

FIG. 16 shows the refractive index changes of the single gratings 4aA and 4bA irradiated with ultraviolet light and the single gratings 4aA and 4b in the optical waveguide device 2D of FIG.
It is a graph showing the relationship of the distance along the longitudinal direction of bA.

FIG. 17 is a block diagram of a film forming apparatus 19a using a CVD method used in a method of manufacturing an optical waveguide device 2 according to a sixth embodiment of the present invention.

18 is a graph showing a relationship between a film forming speed by a CVD method and a substrate temperature in the manufacturing method of FIG.

FIG. 19 is a plan view of an optical waveguide device 2E according to an eighth embodiment of the present invention.

20 is an enlarged view of a single grating 4aE in the curved optical waveguide 3aE of the optical waveguide device 2E of FIG.

FIG. 21 is a graph showing a reflection wavelength characteristic of a comparative example of the eighth embodiment using a single grating formed in a straight line portion of an optical waveguide according to the related art.

FIG. 22 is a graph showing reflection wavelength characteristics of the single gratings 4aE and 4bE formed on the curved optical waveguides 3aE and 3bE of FIG.

FIG. 23 is an enlarged plan view showing a Y-branch portion 7 of the optical waveguide 3b in the optical waveguide device 2 according to the ninth embodiment.

FIG. 24 is a perspective view showing a discrete-type optical transceiver 101 of Conventional Example 1.

FIG. 25 is a perspective view showing an optical transceiver 102 having a micro-optics structure according to Conventional Example 2.

FIG. 26 is a perspective view showing an optical transceiver 103 in which LD and PD sub-modules are mounted on the end face of the PLC of Conventional Example 3;

FIG. 27 is a perspective view showing an optical transceiver 104 using the passive alignment mounting method of Conventional Example 4.

FIG. 28 is a diagram showing an optical waveguide device showing a typical grating forming process of Conventional Example 5 and the periphery thereof;
(A) is a sectional view showing the optical waveguide device and its periphery, (b) is an enlarged sectional view of a region X of (a),
(C) is an enlarged plan view of a region Y of (a).

FIG. 29 is a graph showing reflection spectrum characteristics of a typical grating of the related art.

[Explanation of symbols]

1,1A, 1B, 1C, 1D, 1E Grating type optical transceiver, 2,2A, 2B, 2C, 2D, 2E
Optical waveguide device, 3a, 3b, 3ca, 3cb optical waveguide, 3aE, 3bE Curved optical waveguide, 4a, 4b
Chirp grating, 4aA, 4bA, 4aE,
4bE single grating, 5a, 5b coupler,
6 Non-reflection terminator, 7 Y branch, 8, 8a, 8
b, 8c, 8d substrate, 9a, 9b, 9c optical fiber cable, 10a, 10b cable connection guide groove,
11 photodiode, 12 light emitting diode,
13a, 13b, 13c, 13d Material container, 14
a, 14b, 14c, 14d Mass flow controller, 15 mixed gas of oxyhydrogen, 19 turntable, 20 carrier gas inlet, 21a, 21b,
21c, 21d, 21e Flow controller, 22a, 22
b, 22c, 22d Material container, 23 Optical power meter, 24 Reactor, 25 Ozonizer, 26 Oxygen gas inlet, 27 Exhaust port, 28 Core, 29
Excimer laser beam, 200 rooms.

 ──────────────────────────────────────────────────続 き Continued on front page (72) Inventor Masakazu Takabayashi 2-3-2 Marunouchi, Chiyoda-ku, Tokyo Inside Mitsubishi Electric Corporation (72) Inventor Hideko Uchikawa 2-3-2 Marunouchi, Chiyoda-ku, Tokyo Inside Mitsubishi Electric Corporation (72) Kuniaki Motojima 2-3-2 Marunouchi, Chiyoda-ku, Tokyo Mitsubishi Electric Corporation

Claims (21)

[Claims] 1. A planar optical waveguide device having first and second couplers formed by bringing predetermined two locations of two optical waveguides into close proximity to each other, wherein between the first and second couplers The two positioned optical waveguides are formed by irradiating ultraviolet rays through a chirp grating mask, respectively, to reflect an incident optical signal of a predetermined first wavelength and to transmit an optical signal of a predetermined second wavelength. A planar optical waveguide device comprising a transmission chirp grating. 2. A planar optical waveguide device having first and second couplers formed by bringing predetermined two locations of two optical waveguides into close proximity to each other, wherein the optical waveguide has 20% to 30%. The quartz optical waveguide doped with germanium is formed by high-pressure hydrogen treatment or high-pressure deuterium treatment, and ultraviolet rays are respectively applied to the two optical waveguides located between the first and second couplers. A predetermined first incident, formed by irradiating through a single grating mask
A single grating that reflects an optical signal of a predetermined wavelength and transmits an optical signal of a predetermined second wavelength. 3. A planar optical waveguide device comprising first and second couplers formed by bringing predetermined two locations of two optical waveguides into close proximity to each other, wherein between said first and second couplers The two optical waveguides located are formed in a curved shape, and the two optical waveguides having the curved shape are formed by irradiating ultraviolet rays or X-rays through a single grating mask, respectively, and are formed into a predetermined shape. A planar optical waveguide device comprising a single grating that reflects an optical signal of a first wavelength and transmits an optical signal of a predetermined second wavelength. 4. The optical system according to claim 1, wherein a branching ratio of the first coupler when the optical signal of the first wavelength is branched into two is substantially set to 1: 1, and between the two optical waveguides in the second coupler. Is changed, the second coupler in the second coupler is changed.
The planar optical waveguide device according to any one of claims 1 to 3, wherein a branching ratio when the optical signal having the wavelength of (2) is branched into two is set to a predetermined value. 5. The method according to claim 5, wherein the first and second optical waveguides in the straight portion where the grating is not formed between the first and second couplers are irradiated with ultraviolet rays or X-rays. The planar optical waveguide device according to any one of claims 1 to 3, wherein a branching ratio when the optical signal of the second wavelength is branched into two in the coupler is set to a predetermined value. 6. A reflection bandwidth and a center wavelength of an optical signal of a first wavelength reflected by the grating are changed by irradiating the grating with ultraviolet rays. The planar optical waveguide device according to claim 1. 7. An optical power meter is connected to one output port of the second coupler, and when an optical signal is input to one input port of the first coupler, light of the output port is output. 7. The planar optical waveguide device according to claim 1, wherein the intensity is adjusted to a predetermined value. 8. The planar optical waveguide device has a port on a first side and two ports on a second side,
One port on the second side is connected to one port of the second coupler, further comprising a Y-branch formed by an optical waveguide; 8. The method according to claim 1, wherein the branch ratio of the Y branch portion is changed to a predetermined value by irradiating X-rays.
The planar optical waveguide device according to any one of the above. 9. The optical waveguide according to claim 1, wherein the optical waveguide is made of Si, Ge, P, B,
Reacting at least one or more source vapors of organic alkoxides of Sn and Ti with an ozone gas at a temperature of 600 to 1000 ° C. to form a film mainly containing the oxide on a substrate by a CVD method; 9. The planar optical waveguide device according to claim 1, wherein the planar optical waveguide device is formed by: 10. A method of manufacturing a planar optical waveguide device comprising first and second couplers formed by bringing predetermined two locations of two optical waveguides close to each other, wherein the first and second couplers are provided. By irradiating each of the two optical waveguides positioned between them with an ultraviolet ray through a chirp grating mask, the optical signal having a predetermined first wavelength is reflected and the optical signal having a predetermined second wavelength is reflected. Forming a chirped grating that transmits light. 11. A method for manufacturing a planar optical waveguide device having first and second couplers formed by bringing predetermined two locations of two optical waveguides close to each other, wherein the optical waveguide is reduced by 20% to 20%. Forming a quartz optical waveguide doped with 30% germanium by high-pressure hydrogen treatment or high-pressure deuterium treatment; and two optical waveguides located between the first and second couplers. Irradiating ultraviolet light through a single grating mask to form a single grating that reflects an incident optical signal of a predetermined first wavelength and transmits an optical signal of a predetermined second wavelength. A method for manufacturing a planar optical waveguide device, comprising the steps of: 12. A method of manufacturing a planar optical waveguide device having first and second couplers formed by bringing predetermined two locations of two optical waveguides into close proximity to each other.
Forming two optical waveguides located between the couplers in a curved shape, and irradiating the two optical waveguides having the curved shape with ultraviolet rays or X-rays through a single grating mask, respectively. Forming a single grating that reflects an incident optical signal of a predetermined first wavelength and transmits an optical signal of a predetermined second wavelength. . 13. A step of setting a branching ratio of the first coupler when splitting an optical signal having a first wavelength into two, substantially to 1: 1, and two optical waveguides in the second coupler. By changing the coupling length between the second coupler and the second coupler.
Setting the branching ratio when the optical signal having the wavelength of 2 is branched into two to a predetermined value. The manufacturing method of the planar optical waveguide device according to claim 10, further comprising: Method. 14. A first linear part in which the grating is not formed between the first and second couplers.
Alternatively, the method further includes the step of irradiating the second optical waveguide with ultraviolet rays or X-rays to set a branching ratio when the optical signal of the second wavelength in the second coupler is branched into two, to a predetermined value. 13. The method according to claim 10, wherein:
The manufacturing method of the planar optical waveguide device according to any one of the above. 15. The method further comprises the step of irradiating the grating with ultraviolet light to change and set a reflection bandwidth and a center wavelength of an optical signal of a first wavelength reflected by the grating. The method for manufacturing a planar optical waveguide device according to any one of claims 10 to 14, wherein: 16. An optical power meter connected to one output port of the second coupler; and an output port when an optical signal is input to one input port of the first coupler. 17. The method of manufacturing a planar optical waveguide device according to claim 10, further comprising the step of: adjusting the light intensity to a predetermined value. 17. The planar optical waveguide device according to claim 17, wherein
Side port and two ports on the second side, one port of the second side is connected to one port of the second coupler, and a Y-branch formed by an optical waveguide is provided. Forming a portion, and irradiating a part of the optical waveguide of the Y-branch with ultraviolet rays or X-rays to change a branching ratio of the Y-branch to a predetermined value. 17. The method for manufacturing a planar optical waveguide device according to claim 10, wherein: 18. An ozone gas is reacted with at least one of raw material vapors of organic alkoxides of Si, Ge, P, B, Sn, and Ti at a temperature of 600 to 1000 ° C.
18. The method according to claim 10, further comprising the step of forming the optical waveguide by forming a film mainly containing the oxide on the substrate by using a VD method. 3. The method for manufacturing a planar optical waveguide device according to item 1. 19. The planar optical waveguide device according to claim 8, a light-emitting element connected to one terminal on the second side of the Y branch, and the other terminal on the second side of the Y branch. And a light receiving element connected to the light transmitting and receiving device. 20. The method of manufacturing a planar optical waveguide device according to claim 17, wherein a light-emitting element is connected to one terminal on a second side of the Y-branch portion; Connecting a light receiving element to the other terminal on the side of the optical transceiver. 21. Reaction of at least one kind of raw material vapor of organic alkoxides of Si, Ge, P, B, Sn and Ti with ozone gas at a temperature of 600 to 1000 ° C.
A method for manufacturing a planar optical waveguide device, comprising the step of forming an optical waveguide by forming a film mainly containing an oxide thereof on a substrate by using a VD method.