JPH0652731B2 - Oxidizer - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Field of Industrial Application) [0001] The present invention relates to an oxidation device used for an oxidation treatment of a semiconductor wafer or the like.

(Prior Art) Generally, an oxidizer has been widely used for the oxidation treatment of semiconductor wafers and the like.

FIG. 3 shows a horizontal oxidization furnace which is most frequently used among such conventional oxidizers, and is a chamber (process tube) 1 formed of quartz or the like in a substantially hollow cylindrical shape.
A heater 2 is arranged around the chamber 1, and a hydrogen gas introducing pipe 3 and an oxygen gas introducing pipe 4 are arranged at one end of the chamber 1. A buffer 5 is arranged between the tip of the hydrogen gas introducing pipe 3 in the chamber 1 and a portion where the object to be treated is arranged.

In the oxidizer having the above structure, hydrogen gas and oxygen gas are introduced into the chamber 1 through the hydrogen gas introduction pipe 3 and the oxygen gas introduction pipe 4, and water (steam) and oxygen gas generated by the reaction of the hydrogen gas and the oxygen gas. As a result, a semiconductor wafer or the like (not shown) arranged in the chamber 1 is oxidized.
The buffer 5 is arranged to protect oxides such as semiconductor wafers from the heat generated by the combustion reaction of hydrogen gas.

However, in the above-mentioned oxidation device, since the temperature controllability in the chamber 1 is poor, recently, as shown in FIG.
An external combustion type oxidation device has been developed in which a combustion container 7 provided outside the chamber 1 is connected to one end of the chamber 1 via a ball joint 6 or the like.

In this external combustion type oxidizer, hydrogen gas and oxygen gas are introduced into the combustion container 7 from the hydrogen gas introduction pipe 8 and the oxygen gas introduction pipe 9, and hydrogen is burned in the combustion container 7,
The generated steam is introduced into the chamber 1 without dropping water. The hydrogen gas is often preheated by the heater 10.

In the above external combustion type oxidizer, the chamber 1 described above is used.
The temperature controllability in the chamber 1 can be greatly improved as compared with an oxidizer in which hydrogen is burned inside.

(Problems to be Solved by the Invention) However, in the conventional oxidizer described above, in order to reduce the amount of generated steam, if the amount of hydrogen gas introduced into the combustion container is reduced, combustion becomes unstable. However, the amount of steam generated becomes unstable. Therefore, the amount of water vapor introduced into the chamber becomes unstable, and particularly when the oxidation treatment is performed with low-concentration water vapor, the accuracy of the water vapor concentration decreases, and it becomes difficult to perform the desired oxidation treatment. is there.

The present invention has been made in response to such a conventional situation, and even when performing the oxidation treatment with low-concentration steam, it is possible to maintain the accuracy of the steam concentration at a high level and perform the desired oxidation treatment. It is intended to provide a device.

[Structure of the Invention] (Means for Solving Problems) That is, the present invention relates to a chamber for accommodating an oxide to be oxidized, a combustion container for reacting hydrogen and oxygen to generate water vapor,
In the oxidizer provided with an introduction path for introducing the water vapor from the combustion container to the chamber, a flow dividing means for introducing the water vapor generated in the combustion container to a portion other than the chamber is provided, and It is characterized in that only a part can be introduced into the chamber.

(Operation) In the oxidation device of the present invention, a shunting unit for guiding the water vapor generated in the combustion container to a portion other than the chamber containing the substance to be oxidized is provided, and one of the water vapor generated in the combustion container is It is configured such that only a part can be introduced into the chamber.

Therefore, even when performing oxidation treatment with low-concentration steam, it is possible to reduce only the amount of steam introduced into the chamber while maintaining stable combustion in the combustion container, and to maintain high accuracy of steam concentration. it can.

(Example) Hereinafter, an example of the oxidation apparatus of the present invention will be described with reference to FIGS. 1 and 2.

In the oxidizer of this embodiment, a combustion container 12 is connected to one end of a chamber (process tube) 11 formed of quartz or the like in a substantially hollow cylindrical shape by a ball joint 14 via a water vapor passage 13. .

A hydrogen gas introducing pipe 15 and an oxygen gas introducing pipe 16 are connected to the combustion container 12, and a ceramic heater 17 is arranged in the hydrogen gas introducing pipe 15.

In the water vapor flow path 13, an exhaust flow path 18, heating means such as a ceramic heater 19, and a flow rate controller 20 are arranged in this order from the upstream side.

In the oxidizing device of this embodiment having the above-mentioned configuration, hydrogen gas and oxygen gas are introduced into the combustion container 12 through the hydrogen gas introduction pipe 15 and the oxygen gas introduction pipe 16. At this time, the hydrogen gas is introduced while being heated by the ceramic heater 17.

Then, hydrogen and oxygen are burned in the combustion container 12, and the generated steam and unreacted oxygen gas are transferred to the steam flow path 13
Then, it is heated by the ceramic heater 19 and introduced into the chamber 11 while controlling the flow rate by the flow rate controller 20.

At this time, excess water vapor and oxygen gas due to the control of the flow rate by the flow rate controller 20 are discharged to the outside of the device through the exhaust flow path 18.

Therefore, when the oxidation treatment is performed with low-concentration steam, sufficient hydrogen gas and oxygen gas are introduced into the combustion container 12 such that combustion is not unstable, and among the steam generated by stable combustion, Only the steam necessary for the oxidation process is introduced into the chamber 11 by the flow rate controller 20, and the surplus steam and oxygen gas are exhausted from the exhaust passage 1.
By discharging the water vapor to the outside of the apparatus by 8, the water vapor concentration can be accurately controlled.

FIG. 2 shows an oxidizer of another embodiment. In this oxidizer, an oxygen adsorber 21 is inserted between a branch portion of an exhaust passage 18 of a steam passage 13 and a ceramic heater 19. The oxygen gas supply path 23 including the flow rate controller 22 is connected to the downstream side of the flow rate controller 20. Since the other parts are the same as those in the above-described embodiment, the same parts are designated by the same reference numerals, and the duplicated description will be omitted.

In the oxidizing device of this embodiment having the above-mentioned configuration, of the gases introduced into the chamber 11 from the inside of the combustion container 12, oxygen gas is removed by the oxygen adsorber 21, and the gas introduced into the chamber 11 from inside the combustion container 12 is , Only water vapor. Then, while controlling the flow rate by the flow rate controller 22, the oxygen gas is supplied through the oxygen gas supply path 23 to the water vapor flow path 13.
It is supplied into the chamber 11, mixed with water vapor, and then introduced into the chamber 11.

Therefore, it is possible to obtain the same effect as that of the above-described embodiment, and it is possible to control the ratio of water vapor and oxidizing gas with high accuracy.

[Effects of the Invention] As described above, in the oxidation device of the present invention, even when the oxidation treatment is performed with low-concentration steam, the accuracy of the water vapor concentration can be kept high and the desired oxidation treatment can be performed.

[Brief description of drawings]

FIG. 1 is a block diagram showing a main part of an oxidizer of one embodiment of the present invention, FIG. 2 is a block diagram showing a main part of an oxidizer of another embodiment, and FIG. 3 is a conventional horizontal oxidation furnace. FIG. 4 is a configuration diagram showing a main part of a conventional external combustion type oxidation device. 11 ... Chamber, 12 ... Combustion vessel, 13 ... Water vapor flow path, 15 ... Hydrogen gas introducing pipe, 16 ... Oxidizing gas introducing pipe, 18 ... Exhaust passage, 20 ... Flow rate controller.

Claims (1)

[Claims] 1. An oxidizer comprising a chamber for containing an oxide to be oxidized, a combustion container for reacting hydrogen and oxygen to generate steam, and an introduction path for introducing the steam from the combustion container to the chamber. An oxidizing device characterized in that a diverting means for deriving the water vapor generated in the combustion container to a portion other than the chamber is provided so that only part of the water vapor can be introduced into the chamber.