JPS60131807A - Apparatus for producing wet oxygen atmosphere - Google Patents

Abstract

PURPOSE:To prevent the disorder of the temp. distribution in a treating chamber, and to enhance the safety by introducing gaseous hydrogen and oxygen into a producing chamber consisting of a heat-resistant member, and sending out the formed steam from a delivery port along with the oxygen. CONSTITUTION:The gaseous oxygen is supplied from an oxygen supply pipe 15 into a high-safety and explosion-proof vessel 8 consisting of an inner layer 10 made of quartz and an outer layer 11 made of stainless steel with a heat insulating layer 12 in between, and the gaseous hydrogen is supplied from a hydrogen supply tube 14 extending to the inside of the vessel 8 and then protruding upward at the central part. The steam formed by the reaction of oxygen with hydrogen is supplied along with gaseous oxygen as the wet oxygen into a furnace core tube 26 from a tail tube 27 through a duct 19 and an auxiliary duct 28 while regulating the temp. at a constant temp. with a ribbon heater 30. A heater 16 is equipped to said supply tube 14 to preheat the gaseous hydrogen and to promote said reaction, and the conditions of a flame 20 formed during the reaction is simultaneously observed from an observation window 25. The temp. of the flame is measured with the terminal 21 of a thermocouple having a protector tube 22 to control the reaction.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a wet oxygen generation device, and more particularly to a device for supplying wet oxygen into a reactor core tube in which oxidation treatment or diffusion treatment is performed. For example, regarding heat treatment technology, Electronic Integrated
C1rcuits (J, AI l 1son
(Author), pages 48 to 50.

In the oxidation and diffusion process for semiconductor thin plates (wafers) in the manufacture of semiconductor devices, hydrogen (Hi), oxygen ( A wet oxygen generation method ()-quenching method) based on the direct reaction of , ) is generally employed.

As shown in Fig. 1, this type of oxygen generation method is known as the hydrogen combustion mechanism for
Ru. That is, a hydrogen supply pipe 3 made of quartz glass is inserted into a thin tail pipe 2 of a furnace core tube (process tube) 1 made of quartz glass through the mutual sliding and mating surfaces in an airtight state at °C. Hydrogen (H2) is supplied into the reactor core tube 1. Further, a branch pipe 4 is made at the closed end of the core tube 1 in parallel with the tail pipe 2, and oxygen (0,) is supplied into the core tube 1 through this branch pipe 4. Further, a heater section 5 consisting of a soaking tube, a heater, etc. is arranged on the outer periphery of the furnace core tube 1, and a processing chamber 6 inside the furnace core tube 1 is provided.
is heated to an appropriate temperature. When forming an oxide film on the urethane, it is heated to a predetermined temperature (using a heat treatment jig, etc., not shown in the processing chamber 6).
After taking the conwafer, oxygen is supplied to the processing chamber 6 from the branch pipe 4.
At the same time, hydrogen is also introduced into the processing chamber 6 from the hydrogen supply pipe 3. Since the inside of the processing chamber 6 has reached a predetermined temperature and hydrogen and oxygen are each sent into the processing chamber 6 at a predetermined ratio, the hydrogen and oxygen burn without exploding (-center 7° is shown). and water vapor (shown as a dot in the figure t).

), oxygen containing water vapor, i.e., wet oxygen, is supplied toward the center of the reactor core tube 1 to thermally oxidize (Si) the wafer surface.
0*) film is formed. ,.

However, such a mechanism has the following drawbacks.

S PA (1) The temperature of the elongated reactor core, Homare, is generally controlled by three heaters A, B, and C arranged in a row, and as shown in Figure 2, the temperature distribution in the center is constant. In addition, in order to maintain a constant temperature distribution over a constant length, heaters A and C are located at both ends of the core tube, so that the temperature at both ends of the core tube is slightly higher than that at the center. controlled by. However, when hydrogen and oxygen are reacted and burned at the closed end of the core tube, the temperature rises partially at the back of the core tube, as shown by the two-dot chain line in Figure 2, and the inside of the core tube is uniformly heated. Temperature distribution is impaired and oxide film formation becomes non-uniform. Generally, the central heater B only plays the role of moving the temperature up and down to a certain level, and does not act to correct the temperature difference between the two ends of the reactor core tube.

(2) Confirm safety or proper oxidation film formation, whether or not the ignition (combustion) condition is met.
However, since combustion occurs in the core tube, and the core tube is surrounded by a heater section on the i side, ignition (
Flame 7) How to check the furnace core tube? You have to look through the opening. However, because the wafers are inserted into the reactor core tube in a row, it is difficult to confirm ignition (combustion).

(3) If an explosion occurs due to a change in the mixture ratio of hydrogen and oxygen or the temperature in the processing chamber becomes low, the reactor core tube is made of quartz glass, so it will break into powder and scatter into the surrounding area, creating a dangerous situation. In addition, there is a drawback that the wafer 1 and the heater section are damaged.

(4) Particularly in the case of a diffusion furnace, it is common to provide a new branch pipe in addition to the tail pipe on the closed end side of the reactor core tube in order to supply reaction gas. However, in the above-mentioned method, the structure of the reactor core tube becomes complicated and the manufacturing cost becomes high. In addition, since there are two tail pipes and two branch pipes at the ends of the core tube, which are thin and easily broken, handling is also different from that of conventional 0-tail tube furnaces.

But? SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a sea urchin fish oxygen generating apparatus that does not disturb the temperature distribution within the processing chamber, and a heat treatment furnace having the same.

Another object of the invention is that the ignition state can be easily checked;
Our aim is to provide products that are also highly safe.

□Furthermore, another object of the present invention is to provide a reactor core tube having only a conduit on the closed end side, which is the most common and simple structure.

In order to achieve such an object, an embodiment of the present invention includes an airtight container, an oxygen supply mechanism for supplying oxygen into the container, and a hydrogen jet nozzle protruding into the container. A hydrogen supply mechanism that supplies hydrogen to the hydrogen jet nozzle;
A heating means such as a heater 7 that heats at least the tip and periphery of the hydrogen injection nozzle, and a conduit that guides the water vapor and oxygen generated by reaction at the tip of the hydrogen injection nozzle to the core tube of the heat treatment furnace. The present invention will be specifically explained below using examples shown in the drawings.

1. FIG. 3 is a schematic diagram showing a wet oxygen generation device and a diffusion furnace having the same, which are one embodiment of the present invention. In the figure, an airtight container (box) 8 made of quartz glass is shown. This container 8 is a doping box 9 of a diffusion furnace.
contained within. Further, the container 8 has a three-layer structure, and the innermost layer box 10 is made of solid quartz glass so that it can withstand high temperatures and is free from impurities. Further, the outermost box 11 is made of a metal container, such as stainless steel, which has a strength that will not cause damage even if an explosion occurs inside the container. Also, the outermost box 1
A heat insulating material such as quartz wool is inserted between the box 1 and the innermost box 10 to enhance the heat insulating effect, forming a heat insulating layer 12.

A plurality of pipes 13 are integrally attached to the innermost box 1O on its upper surface and side portions. That is, on the − side wall are a hydrogen supply pipe 14 for introducing hydrogen gas into the container 8 and an oxygen supply pipe 1 for introducing oxygen gas into the container 8.
5 is provided.

The hydrogen supply pipe 14 extends into the container through the innermost box 1o, and its tip protrudes below the center of the ceiling of the innermost box 1o. In addition, the hydrogen supply pipe 14 inside the container 8
A spiral heater 16 is wound around the portion, and both ends thereof are connected to the innermost layer box Eoo.

Heat insulation layer 12. It extends outside the container through the outermost box 11, and is connected to a predetermined power source (not shown). Moreover, this heater 16 is covered with quartz glass on the outside, and
Welded to the innermost box 1o via quartz glass,
The airtightness of the insertion site is maintained. Further, the upper part of the spiral part 17 of the heater 16 is connected to the nozzle part 1 at the tip of the hydrogen supply pipe 14.
8 and heats the periphery of the nozzle portion 18.

Also, the innermost box 10 facing the nozzle part 18
A conduit 19 is provided on the ceiling of the container 8 to direct water vapor (indicated by scattered dots in the figure) generated by the combustion reaction between the hydrogen gas spouted from the nozzle part 18 and the oxygen gas filling the container to the outside of the container 8. There is a button to guide it with oxygen. Additionally, a thermocouple terminal 21 is used to detect the temperature of the flame 20 caused by combustion.
has entered the vicinity of the flame 20 from outside the container. This thermocouple terminal 21 is covered with a protective tube 22 made of quartz glass extending from the innermost box 10 whose inner end is closed.

Further, a drain vibe 23 made of quartz glass is attached to the lower side of the container 8 to drain water accumulated at the bottom of the container. This drain pipe 23 has a drain cock 24.
is provided. Although not shown, the container 8 is provided with a reaction gas supply pipe for processing the object to be processed.

Further, the outermost box 11 and the heat insulating layer 12 are partially removed to form an observation window 25 so that the flame 20 burning inside the container 8 can be observed from outside the container. Note that a transparent protective plate with excellent heat resistance may be attached to the observation window 25 to serve as a protective plate when the innermost box 10 explodes. Further, the innermost box 10. Heat insulation layer 12
has a structure that can be removed sequentially starting from the outermost layer box 11.

On the other hand, the conduit 19 protruding from the container 8 is a standard type reactor core tube 2.
It is connected to the narrow tail tube 27 of No. 6 through an auxiliary conduit 28 made of a tube made of fluororesin or the like. In addition, a connector 29 for connecting this generally known YT pipe is provided at the connecting part.
are used respectively.

Furthermore, a ribbon heater 30 is wrapped around the outer periphery of the connector 29 and the auxiliary conduit 28 to prevent the water vapor flowing inside the auxiliary conduit 28 from turning into water droplets, and to constantly supply wet oxygen at a constant temperature to the reactor core tube. There is. Further, numeral 31 in the figure is a heater section that heats the furnace core tube 26.

Next, the operation of supplying wet oxygen to the furnace core tube 26 will be explained. The vicinity of the nozzle portion 18 of the hydrogen supply pipe 14 is heated to a predetermined temperature by the heater 16, and oxygen gas is injected into the container 8 from the oxygen supply pipe 15 to fill it with oxygen. Further, hydrogen gas is injected from the nozzle portion 18. Note that the hydrogen gas and oxygen gas are supplied in a predetermined ratio. As a result, the hydrogen injected from the nozzle portion 18 reacts with oxygen and burns, generating water vapor. Since the pressure inside the container 8 is high, the water vapor and oxygen (and reactant gases such as diffusion impurities, if necessary) in the container are transferred to the conduit 19. It is sequentially fed into the core tube 26 through an auxiliary conduit 28 .

According to such an embodiment, the following effects can be achieved.

(1) Wet oxygen supplied to the reactor core tube is always maintained at a constant temperature by a ribbon heater and is supplied to the reactor core tube. As a result, the temperature distribution in the furnace tube is stabilized, so that quenching processing with excellent quality and reliability can be performed, and yields can also be improved.

(2) Since the combustion state can be easily observed through the observation window of the vessel, it can be confirmed whether or not steam is being reliably sent to the reactor core tube. Therefore, it is also possible to avoid performing wafer processing in the absence of water vapor.

(3) Even if an explosion occurs inside the container, the outermost box of the container is pressure resistant and strong, so quartz glass fragments will not scatter outside the container as in the case of conventional methods. Therefore, it is safe. Furthermore, since the wafer is not damaged by flying quartz glass pieces as in the conventional case, there is no reduction in yield. Furthermore, since the heater part is not destroyed by flying quartz glass pieces, the life of each part of the heat treatment furnace apparatus is extended, which also leads to a reduction in product processing costs.

(4) Since standard products such as tail pipes can be used for the reactor core tube, equipment costs are also reduced.

Note that the present invention is not limited to the above embodiments. Additionally, this wet oxygen generator can be easily attached to other equipment for use.

[Brief explanation of the drawing]

Figure 1 is a partial cross-sectional view showing a wet oxygen generation mechanism that supplies wet oxygen to the core tube of a conventional diffusion furnace, Figure 2 is a temperature curve diagram showing the temperature distribution in the core tube, and Figure 3 is the invention of the present invention. FIG. 2 is a sectional view showing the present wet oxygen generation device. DESCRIPTION OF SYMBOLS 1... Furnace core tube, 3... Hydrogen supply pipe, 5... Heater part, 6... Processing chamber, 7... Flame, 8... Container, 10
...Innermost box, 11...Outermost box, 1
2... Heat insulation layer, 14... Hydrogen supply pipe, 15... Oxygen supply pipe, 16... Heater, 18... Nozzle part, 1
9... Conduit, 20... Flame, 21... Thermocouple terminal,
25... Observation layer, 26... Furnace tube, 27... Tail tube, 28... Auxiliary conduit, 30... Ribbon heater, 31
...Heater part.

Claims (1)

[Claims] 1Ja) A generation chamber formed of a heat-resistant member; (b) a gas introduction pipe for introducing hydrogen gas into the generation chamber; and (C) introducing oxygen gas into the generation chamber. (d) reaction auxiliary means for promoting the oxyhydrogen combination reaction in the generation chamber; and (e) a delivery hole for delivering the water vapor produced by the reaction. .