JPH05186232A - Apparatus for producing glass thin film - Google Patents

Abstract

PURPOSE:To reduce the inhomogeneity caused in forming many porous glass films. CONSTITUTION:A cylindrical holder 14 housed in a reactional vessel 12 is rotated sound the shaft 24 relatively to the reactional vessel 12 and reciprocated in the direction of the shaft 24. Plural substrates 16 are supported on the side of this cylindrical holder 14. A burner 20 fixed on the side of the reactional vessel 12 is capable of feeding a raw material together with an oxyhydrogen flame onto the substrates 16 on the side of the cylindrical holder 14 to form glass fine particulate layers on the surfaces of the substrates. A heater member 26 housed in the inner space of the cylindrical holder 14 is capable of uniformly heating the plural substrates 16 while rotating relatively to the cylindrical holder 14 round the shaft 28 as the center. Thereby, the temperatures of the respective substrates can be kept constant and the glass fine particulate layers deposited on the respective substrates 16 can be homogenized and regulated to a constant thickness. The substrates 16 are then heated to a high temperature in a furnace and the deposited glass fine particulate layers are transparentized to provide oxide glass thin films.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a glass thin film manufacturing apparatus which can be used for forming an optical waveguide or the like.

[0002]

2. Description of the Related Art FIG. 1 shows a conventional example of an apparatus for producing an oxide glass thin film. In the reaction vessel 6, a plurality of substrates 1 on which the glass particles from the torch 3 are to be deposited are arranged. The glass particles and exhaust gas not deposited on the substrate 1 are sucked into the exhaust pipe 4. In order to uniformly deposit glass particles on the substrate 1, the turntable 2 on which the substrate 1 is placed is rotationally driven by the motor with respect to the reactor 6. Further, the turntable 2 is provided with a lower heater 5 to uniformly heat the substrate 1 placed on the turntable 2. The specific contents of the conventional example are described in JP-A-58-105111.

[0003]

However, in the conventional apparatus, since the turntable 2 and the lower heater 5 are integrated, temperature distribution is likely to occur in the radial direction and the circumferential direction of the turntable 2. For this reason, the film thickness of the porous glass body for the core layer and the buffer layer to be formed on the substrate 1 is nonuniform. Further, since the substrate 1 is arranged one-dimensionally on the turntable 2, there is a certain limit on the number of substrates on which the glass thin film can be simultaneously deposited unless the radius of the turntable 2 is increased.

Therefore, the object of the present invention is to provide an apparatus capable of simultaneously producing a large number of more homogeneous glass thin films by reducing the non-uniformity in the film thickness of the porous glass body to be formed on the substrate. And

[0005]

In order to solve the above-mentioned problems, the glass thin film manufacturing apparatus according to the present invention comprises: (a) a plurality of substrates on which glass thin films are to be formed are equidistant from a predetermined central axis. A cylindrical holder that is supported on the side surface, rotates in the reaction container about the predetermined center axis with respect to the reaction container, and reciprocates in the direction of the center axis; and (b) is fixed to the reaction container side. And a burner for supplying a raw material together with an oxyhydrogen flame to form a glass fine particle layer on a plurality of substrates supported on the side surfaces of the cylindrical holder that rotates and reciprocates, and (c) the cylindrical holder. It heats a plurality of substrates that are housed in the internal space and rotate relative to the cylindrical holder about a rotation axis that is substantially the same as the predetermined center axis of the cylindrical holder, and that are supported by the cylindrical holder. Heater It is set to be provided with the wood.

[0006]

According to the above apparatus for manufacturing a glass thin film, the heater member is arranged in the cylindrical holder relative to the cylindrical holder about a rotation axis substantially the same as the predetermined central axis of the cylindrical holder. Is rotating. Thereby, the temperature distribution at each position of the plurality of substrates supported by the side surface of the cylindrical holder can be kept uniform. As a result, the thickness of the glass fine particle layer deposited on the substrate can be kept uniform, and the glass fine particle layer can be made more uniform. Moreover, since the substrate can be two-dimensionally supported on the side surface of the cylindrical holder, a homogeneous glass fine particle layer can be simultaneously formed on a large number of substrates.

[0007]

EXAMPLES Examples of the present invention will be specifically described below.

FIG. 2 is a perspective view showing the construction of an oxide glass thin film manufacturing apparatus according to an embodiment. The reaction vessel 12 in the muffle furnace has a cylindrical internal space, and a cylindrical holder drum 14 is housed inside the internal space. On the side surface of the holder drum 14, a plurality of substrates 16 (for example, Si substrate, SiO ₂ substrate, etc.) on which a glass fine particle layer should be deposited.
I is supported by a fixing plate 18 which is screwed. A gas ejection port of the burner 20 is fixedly provided on the side wall of the reaction container 12 so as to face the side surface of the holder drum 14.
Fuel and source gas are supplied to the burner 20. From the burner 20, the oxyhydrogen flame generated by the fuel gas and the oxide glass fine particles synthesized from the raw material gas by this are supplied onto each substrate 16. The glass particles and the exhaust gas not deposited on these substrates 16 are removed from the reaction container 1
It is sucked into the suction port of the exhaust pipe 22 fixed to the side wall 2 of the burner 20 so as to face the burner 20.

In order to uniformly supply and deposit glass particles on each substrate 16, a holder drum 1 for supporting the substrate 16 is provided.
4 rotates about its central axis and reciprocates vertically in the reaction vessel 12. Ie burner 2
0 results in two-dimensional scanning of the side surface of the holder drum 14. The rotation and reciprocal movement of the holder drum 14 are controlled by the support shaft 24 fixed to the upper portion of the holder drum 14.
It is controlled from outside the muffle furnace via. in this case,
By flowing the purge gas around the support shaft 24, it is possible to prevent outside air from flowing into the reaction container 12.

Further, in order to keep the temperature of each substrate 16 supported on the side surface of the holder drum 14 constant, the holder drum 14
A cylindrical heater member having a heating element for generating heat rays formed on its surface is provided in the internal space of. FIG. 3 is a side sectional view showing this heater member. Heater member 26
Is close to the inner wall of the holder drum 14, but is not in contact with the holder drum 14, and is rotatable with respect to the holder drum 14. In this case, the heater member 26 does not rotate relative to the reaction container 12. However, it is necessary to move the heater member 26 according to the vertical position of the holder drum 14. The vertical movement of the holder drum 14 is controlled from the outside of the muffle furnace via a support shaft 28 fixed to the lower portion of the holder drum 14. In this case, by flowing the purge gas around the support shaft 28, the reaction container 12
It is possible to prevent outside air from flowing into the holder drum 14.

Further, although not shown, in order to keep the temperature of each substrate 4 supported on the side surface of the holder drum 14 more constant, comb-shaped heating elements are uniformly formed around the heater member 26. Has been done. The heating state of this heating element is controlled by an external power supply device 32 via a wire 30 passing through the support shaft 28.

The operation of the manufacturing apparatus shown in FIGS. 2 and 3 will be briefly described. By supplying the fuel and the source gas to the burner 20, the oxide glass fine particles are deposited on each substrate 16. At the same time, since the holder drum 14 is rotated and reciprocally moved in the vertical direction of its rotation axis, the glass fine particles from the burner 20 are uniformly supplied onto each substrate 16. Further, the heater member 26 rotates relative to the holder drum 14 and the holder drum 1
Since each of the substrates 16 supported by the side walls of No. 4 is uniformly heated, the temperature of each substrate 16 can be kept constant. That is, since each substrate 16 follows a similar thermal history, the glass fine particle layer deposited on each substrate 16 can be made uniform and uniform in thickness within the same substrate or between the substrates.

Thereafter, each substrate 16 is placed in another furnace for 1000
A glass thin film can be obtained by heating to a high temperature of ℃ or more to make the deposited glass fine particle layer transparent. Further, by repeating the above operation and combining etching by RIE or the like, an optical waveguide having a predetermined pattern can be formed on each substrate 16.

An example of manufacturing a glass thin film using the manufacturing apparatus shown in FIG. 2 will be described below. When depositing soot of glass particles, a 3-inch silicon wafer was used as the substrate 16, and these were appropriately arranged on the surface of the holder drum 14.

The deposition conditions of the glass fine particles are that the rotation speed of the holder drum 14 is about 10 rpm, and the holder drum 1
The reciprocating speed of 4 was 20 mm / min. At this time,
The heater member 26 was set so that the temperature of the holder drum 14, that is, the silicon wafer was 800 ° C. The raw material of the soot layer to be the buffer layer is SiCl ₄ (150 cc /
Min), BCl ₃ (20 cc / min) and PoCl ₃ (1 c
c / min) and the formation time was 90 minutes. The raw material of the soot layer to be the core layer is SiCl ₄ (150 cc
/ Min), GeCl ₄ (30 cc / min), BCl ₃ (20
cc / min) and PoCl ₃ (1 cc / min) with a formation time of 30 minutes. In other words, the composition of the soot layer being _{deposited, B 2 O 3 -P 2 O} 5 with soot to become the buffer layer -
SiO ₂ becomes, B ₂ O ₃ in soot layer to become the core layer -
The _{P 2 O 5 -SiO 2 -GeO 2} .

The double layer soot layer deposited as described above is heated in a separately prepared heating furnace under a mixed gas atmosphere of He (helium) and O ₂ gas at a heating temperature of 12
Transparent glass was formed at 80 ° C. to obtain a glass thin film having a double structure. At this time, the supply amounts of He (helium) gas and O ₂ gas were 5 l / min and 0.51 / min, respectively, and the supply ratio was 10: 1. The thickness of the obtained glass thin film was different by 0.5 μm between the one formed on the upper portion of the holder drum 14 and the one formed on the lower portion thereof. The difference in film thickness was measured by an optical interference method.

Next, the core layer is processed by combining the lithography technique and etching such as RIE to form a linear waveguide pattern on the buffer layer. Figure 2 again
The soot layer is deposited on the waveguide pattern and made transparent by using the manufacturing apparatus of 1. to form a clad glass layer. The raw material of the soot layer to be the clad glass layer is SiCl ₄ (150
cc / min), BCl ₃ (20 cc / min) and PoCl ₃
(1 cc / min) and the formation time was 60 minutes. That is, the composition of the deposited soot layer is B ₂ O ₃ —P ₂ O ₅ —SiO _{2 which} is the soot that should form the buffer layer. In this case, the soot layer was made transparent as in the case of the buffer layer. By the above process, width x height is 5μm × 6μm
Thus, a waveguide type device incorporating a linear waveguide having a relative refractive index difference of 0.5% was obtained.

Butt-Coupling for attaching an optical fiber to the end face of the obtained waveguide type device
The loss was measured by 0.08 dB / c
m was relatively good.

The present invention is not limited to the above embodiment. For example, the heater member 26 in the holder drum 14 may be vertically reciprocated in order to increase the homogeneity of the temperature distribution in the vertical direction. Alternatively, the holder drum 14 may be fixed, and the burner 20 may be rotated and moved up and down together with the reaction container 12 around the holder drum 14.

[0020]

As described above, according to the glass thin film manufacturing apparatus of the present invention, since the heater member is rotated in the cylindrical holder relative to the cylindrical holder, The temperature distribution at each position of the plurality of substrates supported on the side surface of the holder can be kept uniform. As a result, the thickness of the glass fine particle layer deposited on the substrate can be kept uniform, and the glass fine particle composition can be made more uniform. Moreover, since the substrate can be two-dimensionally supported on the side surface of the cylindrical holder, a homogeneous glass fine particle layer can be simultaneously formed on a large number of substrates.

[Brief description of drawings]

FIG. 1 is a diagram showing a conventional apparatus for producing an oxide glass thin film.

FIG. 2 is a diagram showing an apparatus for manufacturing a glass thin film of an example.

3 is a sectional view of the manufacturing apparatus in FIG.

[Explanation of symbols]

12 ... Reaction container, 14 ... Cylindrical holder, 16 ... Substrate, 2
0 ... Burner, 26 ... Heater member.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Haruhiko Aikawa 1 Taya-cho, Sakae-ku, Yokohama-shi, Kanagawa Sumitomo Electric Industries, Ltd. Yokohama Works (72) Satoshi Hirose 1 Taya-cho, Sakae-ku, Yokohama, Kanagawa Sumitomo Denki Kogyo Co., Ltd. Yokohama Works (72) Inventor Masahide Saito 1 Taya-cho, Sakae-ku, Yokohama-shi, Kanagawa Sumitomo Denki Kogyo Co., Ltd. Yokohama Works

Claims (1)

[Claims] 1. A plurality of substrates on which a glass thin film is to be formed are supported on side surfaces that are substantially equidistant from a predetermined central axis, and the predetermined central axis is centered in the reaction vessel with respect to the reaction vessel. A cylindrical holder that rotates and reciprocates in the direction of the predetermined central axis, and the plurality of substrates that are fixed to the reaction container side and that are supported on the side surfaces of the cylindrical holder that rotates and reciprocates. A burner that supplies a raw material together with an oxyhydrogen flame to form a glass fine particle layer, and is housed in the internal space of the cylindrical holder, and about a rotation axis substantially the same as a predetermined central axis of the cylindrical holder, An apparatus for manufacturing a glass thin film, comprising: a heater member that rotates relative to the cylindrical holder and that heats the plurality of substrates supported by the cylindrical holder.