KR20010099086A - controling methode torch and turntable for flame hydrolysis deposition - Google Patents

Abstract

The present invention relates to a torch and a table control method of a flame hydrolysis deposition apparatus. The object of the present invention is to move the torch by one pitch in the center or radial direction of the turntable each time the turntable is rotated once, or at the outside (end) or center of the turntable. As the part gets closer to its center or end, the speed of the torch or the turntable increases and decreases so that the relative speed of the substrate and the torch can be constantly controlled regardless of the turntable radius of the position on which the substrate is seated. The oxide fine particle deposition layer was obtained.

According to the present invention, a raw material is placed in the torch 14 at a turntable rotation step of seating the substrate 12 on the edge portion of the turntable 10a and rotating the turntable 10a, and at the top of the turntable 10a rotated by the rotation step. (Phosphorus-containing gas and silicon-containing gas) are supplied to the center of the turntable 10a or its radial direction while producing oxide fine particles by combustion reaction, and are densified by heat treatment on the surface of the substrate 12 on the turntable 10a. In the method for controlling a hydrolysis deposition apparatus having a torch transfer step of depositing the torch, the torch transfer step rotates the turntable 10a constantly while the torch is moved closer to the center of the outer portion of the turntable 10a. It is characterized in that the speed increase means for increasing the speed of 14).

Description

Control methode torch and turntable for flame hydrolysis deposition

The present invention relates to a method for controlling a torch according to constant speed rotation of a turntable in a flame hydrolysis deposition apparatus, and more particularly, a relative speed of a torch is constantly constant regardless of a turntable radius of a position where a substrate is seated. It relates to a control method of a flame hydrolysis deposition apparatus that can obtain a flat and uniform deposition thickness by controlling the speed of.

Usually, the Apparatus for Flame Hydrolysis Deposition (abbreviated as "FHD") is derived from VAD (vacuum application deposition) apparatus, which is an optical fiber manufacturing method, to supply raw materials in the torch at atmospheric pressure to burn. By depositing oxide fine particles on a substrate.

The substrate of the finished product manufactured by the FHD has a lower cladding layer and a core layer mainly composed of quartz on the surface of the substrate, and a core is formed on the lower clad layer by a reactive ion etching method and the core is buried. An upper cladding layer containing quartz as a main component is formed.

As described above, the conventional method of depositing the upper / lower cladding layer and the core layer on the substrate by using the FHD transfers the torch while rotating the turntable, and transfers the torch after transferring the left and right (or front and rear) transfer tables. There is a method of transferring in stages.

The former method involves placing a substrate on a plurality of seating recesses formed at equal intervals so as to have the same radius on the turntable edge portion of the reaction chamber at atmospheric pressure (atmospheric pressure), and a gas containing silicon and a gas containing silicon on top of the turntable. Is supplied to the torch and reacted by a continuous combustion method so that oxide fine particles are produced.

The torch is positioned at a position larger than the substrate end radius of the turntable, i.e., at the edge of the turntable, while creating an atmosphere to stabilize the oxide fine particles of the torch.

In this state, the turntable is rotated at a constant rotational speed, and at the same time, the torch is moved toward the center of the turntable, thereby depositing a densified glass thin film on the substrate surface on the turntable.

At this time, the transfer of the torch is described as being moved in the center direction of the turntable, but it can be reciprocated in the radial direction from the position of the center side of the turntable according to the thickness of the oxide fine particles to be deposited. It can be represented as a swirl.

In the former method using the turntable as described above, the feed rate of the turntable and the torch is the same, so that the vortex-shaped torch rule appears. As the torch nears the center of the turntable, the radius of rotation becomes smaller. The linear velocity of the portion near the center is relatively lower than that of the outer portion. Accordingly, there is a problem in that the thickness of the oxide fine particle layer deposited on the substrate surface is thinner than the inner part of the turntable than the inner part of the turntable, and as a result, the oxide fine particle layer of the substrate is not uniform and the yield of the product is lowered.

In the latter method, as shown in Fig. 1, the substrate 12, which is a wafer, is placed on each of two to four seating recesses formed on a transfer table 10 in a reaction chamber (not shown), which is atmospheric pressure (atmospheric pressure). At the top of the table 10, a gas containing phosphorus and a gas containing silicon are supplied to the torch 14 to react by a method of continuous combustion to produce oxide fine particles.

As described above, when the transfer table 10 is moved left and right while the fine particles are generated in the torch 14, the torch 14 is perpendicular to the direction in which the transfer table 10 is transferred when the torch 14 is stopped. By repeating the process of transferring in the direction (front and rear direction), the glass thin film densified by heat treatment is deposited on the surface of the substrate 12 on the transfer table 10.

At this time, the transfer of the transfer table 10 should be secured enough transfer stroke to accelerate and decelerate at least past the edge position of the substrate 12 at both ends of the transfer table 10, the torch rule on the transfer table 10 is shown in FIG. It can be represented in a zigzag shape as shown in 2.

In the latter method using the transfer table as described above, the pitch of the torch 14 is uniform and the speed of the torch 14 passing through the substrate is constant because the torch rule on the transfer table 10 is linearly transferred in a zigzag shape. As a result, the thickness of the oxide fine particle layer deposited on the surface of the substrate 12 was uniform, so that the yield of the product was better than that of the turntable method.

However, in the latter method using the transfer table, in consideration of working conditions, it is inevitable to mount two to four substrates on the transfer table 10, which makes it impossible to mass-produce them compared to the turntable method of mounting ten or more substrates 12. There was this.

An object of the present invention has been researched and developed to solve the conventional problems as described above, the torch centered at the outer portion of the turntable while moving the pitch of the turntable by one pitch in the center or radial direction each time the turntable is rotated once The closer to, the higher the speed of the torch or the turntable, so that the relative speed of the substrate and the torch can be constantly controlled regardless of the turntable radius of the position where the substrate is seated, thereby obtaining a flat and uniform oxide particle deposition layer. The present invention provides a torch and turntable control method of a flame hydrolysis deposition apparatus.

1 is a plan view showing a torch and a table control method of a conventional flame hydrolysis deposition apparatus,

Figure 2 is a side view showing a torch and a turntable control method of the flame hydrolysis deposition apparatus according to the present invention,

3 is a graph showing the moving speed of the torch according to the moving position of the torch in the method of the present invention.

<Explanation of symbols for main parts of drawing>

10a: turntable 12: substrate

14: torch

The present invention, in order to achieve the above object, the turntable rotation step of seating the substrate in each of the plurality of recess groove formed in the edge portion of the turntable and rotates the turntable, the raw material in the torch at the top of the turntable rotated by this rotation step A torch transfer step of supplying (phosphorus-containing gas and silicon-containing gas) to produce oxide fine particles by combustion reaction and moving in the center or radial direction of the turntable to deposit a glass thin film, which is densified by heat treatment, on the substrate surface on the turntable. In the control method of the FHD, the torch and the turntable control method of the FHD, characterized in that the increasing speed of the torch is increased as the torch transfer step rotates the turntable constantly, the closer to the center from the outer portion of the turntable. to be.

The torch transfer step may be provided as a deceleration means that the speed of the torch is decelerated as it moves away from the center of the turntable toward the end.

In the speed increasing means of the torch moving step, V: the feed speed of the torch, R: distance from the center of the table to the end (radius), r1: distance from the end of the table to the initial position, r2: distance from the end of the table to the final position, V1: initial feed speed of the torch, V2: final feed speed of the torch, A & B: V = A / (R-rx) + B when it is a variable by user input.

Hereinafter, a torch and a turntable control method of an FHD according to the present invention will be described in detail with reference to the accompanying drawings.

Figure 2 is a plan view showing a torch and a turntable control method of the flame hydrolysis deposition apparatus according to the present invention, Figure 3 is a side view of FIG.

Rotation step: The substrate 12 is seated in each of the plurality of seating recesses formed in the edge portion of the turntable 10a, and the turntable 10a is rotated at a constant rotation rate per minute.

Torch transfer step: The raw material (phosphorus-containing gas and silicon-containing gas) is supplied to the torch 14 from the upper part of the turntable 10a rotated by the rotating step so that oxide fine particles are generated by the combustion reaction and the turntable 10a is By moving in the center direction, a glass thin film densified by heat treatment is deposited on the surface of the substrate 12 on the turntable 10a.

In the torch conveying step, a speed increasing means for increasing the speed of the torch 14 as the turntable 10a is constantly rotated is closer to the center of the outer portion of the turntable 10a.

In the speed increasing means of the torch moving step

V: feedrate of torch 14, 14

R: distance from the center of the turntable 10a to the end (radius),

r1: distance from the end of turntable 10a to the initial position,

r2: distance from the end of turntable 10a to the final position,

V1: initial feed rate of the torch 14,

V2: final feed rate of the torch 14,

A & B: Given a variable by user input, the feed rate of the torch 14 can be obtained from the following equation.

V = A / (R-rx) + B

In the torch transfer step, the speed of the torch 14 is increased from the end of the turntable 10a toward the center, but as the distance from the center of the turntable 10a to the center increases, the speed of the torch 14 decreases. Of course, it can also be provided as a deceleration means.

An embodiment of the torch and turntable control method of the above-described FHD will be described.

First, the substrate 12 is seated for each mounting recess of the turntable 10a, and then the turntable 10a is driven at about 8 to 15 revolutions per minute. The torch 14 was transferred at a speed corresponding to the value obtained by substituting the equation V = A / (R-rx) + B while the turntable 10a was rotated.

At this time, the radius R of the turntable 10a is 450 mm, the initial speed of the torch 14 is 20 mm / min, the final speed of the torch 14 is 220 mm / min, and the initial position of the torch 14 r1) is 20 mm and the final position r2 of the torch 14 is 160 mm.

In the above equation, the speed of the torch 14 according to the moving position of the torch 14 was obtained as shown in FIG. 3.

Therefore, it was confirmed that the deposition of silica, which is an optical waveguide, on the wafer, which is the substrate 12, was deposited with a uniform thickness without variation.

As described in detail above, the FHD torch and turntable control method according to the present invention moves the torch by one pitch in the center or radial direction of the turntable each time the turntable is rotated by one or the center thereof at the end or the center of the turntable. As it gets closer to the tip, the speed of the torch or the turntable increases and decreases the relative speed of the substrate and the torch at any time, regardless of the turntable radius of the position on which the substrate is seated. There is a unique effect that can be obtained.

Claims (3)

The turntable rotation step of seating the substrate 12 in each of the plurality of recessed grooves formed at the edge of the turntable 10a and rotating the turntable 10a, and the torch 14 at the top of the turntable 10a rotated by the rotation step. ) Supplying raw materials (phosphorus-containing gas and silicon-containing gas) to the center of the turntable 10a or its radial direction while producing oxide fine particles by combustion reaction, thereby densifying by heat treatment on the surface of the substrate 12 on the turntable 10a. In the torch and turntable control method of a flame hydrolysis deposition apparatus having a torch transfer step of depositing a thin glass film, Flame torch deposition apparatus characterized in that the torch conveying step is provided with a speed increasing means to increase the speed of the torch 14 closer to the center at the outer portion of the turntable (10a) while constantly rotating the turntable (10a) Torch and turntable control method. According to claim 1, The torch conveying step is provided as a deceleration means that the speed of the torch 14 is reduced as the distance from the center of the turntable (10a) toward the end while moving toward the end of the turntable (10a) Torch and turntable control method of the flame hydrolysis deposition apparatus, characterized in that. 2. The speed increasing means of the torch moving step according to claim 1, wherein V is the conveying speed of the torch, R is the distance from the turntable center to the end (radius), r1 is the distance from the turntable end to the initial position, and r2 is at the turntable end. Distance to final position, V1: Initial feedrate of torch, V2: Final feedrate of torch, A & B: Flame hydrolysis characterized in that V = A / (R-rx) + B when it is variable by user input. Torch and turntable control method of deposition apparatus.