JPS63115343A - Processor - Google Patents

Abstract

PURPOSE:To improve the evenness in processing while accelerating the decomposition and removal speed by a method wherein a flow channel of O2 containing gas is formed of an inorganic material transmissive ultraviolet rays while discharging nozzles with slit type pores are used. CONSTITUTION:An organic material is irradiated with ultraviolet rays to be removed by means of forming a simple molecule such as CO2, H2O, O2, etc., reacting to optically decomposed compound or excited O. At this time, the ultraviolet rays in 184.9 nm or 253.7 nm play an important role in decomposing the organic material. When a gas flow channel is formed of a material transmissive ultraviolet rays in 184.9 nm or 253.7 nm producing O to irradiate gas with the ultraviolet rays, O2 is led into the processing chamber 11 while producing O3 and O in the flow channel. Furthermore, mixed gas containing O3 is irradiated with the same ultraviolet rays before the ultraviolet rays are through an ozone producer 16 to prevent the deterioration in concentration due to extinction of O3 from occuring while accelerating the production of O to be led into the processing chamber 11. Resultantly, the organic material in high concentration of O3 and O can be rapidly decomposed on the other hand, the slit type nozzles 15 at gas outlet play an important role in the evenness in the processing.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention is a method of irradiating ultraviolet rays (hereinafter referred to as UV light) or irradiating UV light and heating an object to be treated that is contaminated with organic matter and where oxygen is present. The present invention relates to a processing device that decomposes and gasifies organic substances into substances such as CO2, CQ, and H2O, and removes them to clean objects. Objects to be treated that require such cleaning include:
IC manufacturing substrates (hereinafter referred to as wafers), liquid crystal display substrates, two image, audio or numerical recording disks.

There are other electronic parts, etc.

Conventional technology In recent years, it has become necessary to remove contaminants that adhere to the surfaces of Ueno, liquid crystal display substrates, various disks, etc. in order to improve product yield and reliability in the manufacturing process. It has become to. On the other hand, conventionally, NH4O
Contaminants were decomposed and removed using a mixture of H and H2O2 or HCl and H2O2, or they were scraped off with a brush using ultrapure water. However, with these methods, for example, several molecular layers of organic matter, which is one of the contaminants, could not be removed, or if a brush was used, there was a risk that dirt would adhere instead.

Also, when cleaning in wet conditions like this, wash with water.

A drying process is required, and during this process, the items to be cleaned may be re-contaminated by contaminants generated from the equipment or water droplets splashed from the items to be cleaned, and it is necessary to control the quality of ultrapure water. Met.

On the other hand, as a device for decomposing and removing organic matter that does not cause such trouble, there is a treatment device using ozone (03) as shown in FIG. An example of a conventional processing device will be described below with reference to FIG. In Figure 6, 41
is a processing chamber, 42 is a wafer to be processed, 43 is a low-pressure mercury lamp, 44 is a gas storage chamber made of SUS, 45 is a gas discharge nozzle (made of SUS), 46 is a 03 generator, and 47 is a wafer with a heater. The mounting stand, 48.49, is piping. The operation of the processing device configured as above will be explained.

First, the wafer 2 is heated in the processing chamber 41 (1oo to 300
02 gas (
1oooSCCM) is guided to the 03 generator 46 by silent discharge through the pipe 49, and the mixed gas of 02 and 03 is introduced to the pipe 4.
The gas is introduced into a gas holding chamber (made of SUS) 44 through a gas discharge nozzle (made of SUS) to equalize the gas pressure, and uniformly exits from the processing chamber 41 through a gas discharge nozzle (made of SUS).

Further, a low-pressure mercury lamp 43 is turned on in the processing chamber 41, and ultraviolet light of 184.9 nm and 253.7 nm is irradiated to decompose the organic substances on the surface of the mercury 42 by interaction with the 03.

Problems to be Solved by the Invention However, in the above configuration, the problem occurred in the 03 generator 46. 3 is piping 48. Gas retainer 44 and nozzle 45
The O3 concentration 5beno decreases as the O3 concentration disappears during the passage, and the time that O2 and O3 are exposed to ultraviolet light is shortened, and the amount of oxygen radicals (O.) is small, so the decomposition rate of organic matter is slowed down. In addition, a gas discharge nozzle 45
has a simple cylindrical shape, as shown in FIG. When such a nozzle 45 is used for processing, there is a problem in that the decomposition of organic matter is fast only on the surface of the wafer 42 directly under the nozzle 45, and is completely slow on the other parts, resulting in very poor uniformity of processing.

In view of the above problems, the present invention has a high decomposition rate of organic matter,
The present invention also provides a processing apparatus that has excellent uniformity of processing and does not contaminate objects to be processed with metal, fine particle dust, or the like.

Means for Solving the Problems In order to solve the above-mentioned problems, the processing apparatus of the invention in column 1 of the present invention has the following features:
The gas flow path containing the gas is made of an inorganic material that transmits ultraviolet light of at least 184.9 nm and 253.7 nm, and the processing apparatus of the second invention of the present invention is the same as that of the first invention. In addition to the configuration, to obtain uniformity of processing, 02
The six-vane nozzle for discharging gas containing gas is composed of a nozzle having a slit shape or a plurality of pores.

The decomposition mechanism of organic matter due to actions 02 and 03 is as follows: (1) O radical (○・) (i+) generated at o2ka03 and null time (202-03+0・)03ka decomposes, and at null time (03 -02
○・ generated in +O・) has strong oxidizing power and oxidizes and decomposes organic matter, resulting in Co.

Removed as CO2 or H20 gas. Above (1)
In the reaction equation of (1j), the promoting effect is 184, 9 nm ultraviolet light, discharge phenomenon, and radiation such as X-rays and cathode rays, and in the reaction equation (1j), the promoting effect is 253,
This is 7 nm ultraviolet light.

Furthermore, the energy of 184.9 nm ultraviolet light is 647
K I/mot, 253, for 7 nm ultraviolet light is 472 K I /mol, and the binding energy of various molecules of organic matter is C-0347,7 to 7/motC-H413,4 KJ/
mo7C-0361,5KI/motO-H462,8
KI/mot7bae.

C-N 291.6KJ/zno7 0-0 138
．． 9KJ/mo7C=C607Kl/motC-=Cs
28 Kl/mol: C=0 724 KJ/l
no/: C-C1328, 4KJ/m0AC-F4
41. ○niko/moi N-H390,8KT/mo
A: When exposed to ultraviolet light, organic matter is photodecomposed or excited and reacts with ○, producing CO2 and H2C.

It is removed from the surface forming simple molecules such as o2.

Therefore, 1B4.9am and 253.7am ultraviolet light plays an important role in decomposing organic matter.

Therefore, 184.9am and 253.7 which generate 0.
The gas flow path is made of a material that transmits ultraviolet light, and when the gas is irradiated with ultraviolet light, 02 repeats reactions (1) and (11) in the flow path, generating 03 and 0, and enters the processing chamber. be introduced. In addition, by irradiating the mixed gas containing 03 with ultraviolet light before irradiating it with ultraviolet light through the ozone generator, it enters the processing chamber while preventing the concentration from decreasing due to the disappearance of 03 and promoting the generation of O. Therefore, the concentration of 03 and O. is higher and the organic matter can be decomposed and removed more quickly than in the case where ultraviolet light is applied for the first time after entering the processing chamber as in the conventional apparatus.

On the other hand, the shape of the nozzle, which is the gas outlet, plays an important role in the uniformity of processing. With a conventional nozzle, organic matter decomposes quickly only in the area directly below the nozzle, and is completely slow in the rest of the area, making uniformity extremely insensitive. In order to improve this, it is effective to discharge gas from a plurality of pores.

The greater the number of pores, the better the uniformity of the treatment.

In order to further increase the uniformity, it is better to move the object by rotating it, reciprocating it, or the like. In this case, in addition to the above-mentioned nozzle with small holes, a nozzle with a slit-shaped discharge port is also effective.

The material that transmits short wavelength ultraviolet light such as 184.9 am and 253.7 am is SiO2 (fused silica).

crystal, etc.), Su7fire, MgF2, LiF, CaF2
Although any material may be used, fused silica is preferable from the economical point of view.

The location of the low-pressure mercury lamp that generates ultraviolet light is preferably close to the object being processed. 1 generated by low-pressure mercury lamps
Light such as 84.9 am and 253.7 am is absorbed as described above when there is a 9 vane 03, but the absorbed dust is absorbed by the concentration (or pressure) of 03 and the low pressure mercury lamp based on the Lambert-Beer law. decreases exponentially with distance from Therefore, 03 and O can be effectively removed on the surface of the workpiece.
・In order to generate 02 gas, it is better to shorten the distance between the low-pressure mercury lamp and the object to be treated in high-concentration 02 gas.

Embodiment Hereinafter, a processing apparatus according to an embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram of a processing device in a first embodiment of the present invention. In Figure 1, 11 is a processing chamber (made of SUS)
, 12 is a wafer to be processed, 13 is a low-pressure mercury lamp, 1
4 is a quartz gas storage chamber, 15 is a gas discharge nozzle (made of quartz), 16 is an 03 generator, 17 is a wafer stand that can be heated and rotated with a heater, 18 is quartz piping, 19 is SUS piping, 2o is a motor that rotates the wafer placement table 17. FIG. 2 is an enlarged view of the gas discharge nozzle 15.
are gas discharge pores (φ1 to φ1.5), and discharge pores are provided in one discharge waste 10 benol 15 every 2a in the direction of the wafer table 17. The operation of the first embodiment will be explained with reference to FIGS. 1 and 2. Surface photoresist (OFPR-soo;
Wafer 12 coated with Tokyo Ohka M, 1.0 pm thick)
The wafer mounting table 17 is heated (250°C) in the processing chamber 11.
After placing the wafer by hand, the wafer placement table 17 is rotated by the motor 2o (0, 2 rpm).

After that, the low-pressure mercury lamp 13 is turned on, and 02 gas (1o0
0SCCM) through the pipe 19 by silent discharge. The gas is introduced into the gas reservoir 14 through the 3 generator 16 and the piping 18, and after making the gas pressure uniform, it is introduced into the gas discharge nozzle 15 and discharged from the discharge hole 21. Also, piping 18. The gas reservoir 14 and discharge nozzle 15 are made of quartz, and the ultraviolet light emitted from the low-pressure mercury lamp 13 is directed to the wafer 12 below. 02 in upper gas reservoir 14
103 mixed gas and 02,03 mixed gas in the discharge nozzle 15 can be irradiated. By ashing (ashing) the photoresist in this manner, the entire surface of the wafer 12 could be removed almost uniformly.

A second embodiment of the present invention will be described below.

Figure 3 shows the wafer table 17 and motor 2011 in Figure 1.
FIG. 2 is a plan view of a wafer rotation support stand using an attached gas instead of a wafer. In Fig. 3, numeral 31 is a wafer holder having a large circular shape around the periphery of the wafer, `32 is a gas conduit used to levitate and rotate the wafer, and 33 is a discharge port for the gas. .

Reference numeral 34 indicates a rod heater for heating, and 35 indicates the rotation direction of the wafer.

FIG. 4 is an enlarged sectional view of the gas discharge port 33 taken along line AA in FIG. The outlet pipe 36 between the gas conduit 32 and the gas discharge port 33 forms an angle of 45° with the surface of the wafer placement section 31 in order to levitate and rotate the Uni-No with the gas jet force. The force acts as a buoyant force on the wafer, and the horizontal force acts as a rotational force in the tangential direction of the wafer rotation. As the gas used for floating and rotating the wafer, 02 gas branched from the piping 18 in FIG. 1 was connected to the gas conduit 32 through a quartz tube. In addition, the gas discharge nozzle 1 in FIG.
A slit-shaped gas discharge nozzle (made of quartz) attached in place of 5 is shown in FIG. The nozzle of this method has a width of 21 mm instead of the nozzle having a plurality of discharge holes 21 used in the first embodiment. A slit 37 having a length of 10 mm is provided, and a mixed gas of S02°Q3 is discharged toward the wafer through this slit 37.

The amount of gas from the nozzle 3A was adjusted to 1100 OSCC, and the amount of gas from the gas discharge port 33 was adjusted to 800 SCCM using a valve (not shown). When the photoresist on the wafer was ashed using this device in the same manner as in the first example, the uniformity of the ashing was excellent as in the first example. It was confirmed by measuring the number of dust particles on the wafer using a laser surface inspection device that there was no dust on the wafer, and therefore the processing equipment did not generate dust and could be processed in a clean state.

In the first and second embodiments, the 03 generator 16 uses silent discharge, but an 03 generator using corona discharge or radiation may also be used.

Effects of the Invention As described above, the present invention provides an advantageous effect on the object to be treated by making the flow path for gas containing O2 from an inorganic material that transmits ultraviolet light of at least 184.9 nm and 253,7 nm. The rate of decomposition and removal of attached organic matter can be improved.

Further, by using a slit-shaped or a plurality of pores as the discharge port of the discharge nozzle for the gas containing 02, the uniformity of the treatment is improved.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of a processing apparatus according to a first embodiment of the present invention, FIG. 2 is an enlarged sectional view of the nozzle of FIG. 1, and FIG. 3 is a wafer processing apparatus of a processing apparatus according to a second embodiment of the present invention. FIG. 4 is a sectional view taken along the line A-A in FIG. 3, FIG. 5 is a partial sectional view of a nozzle with a slit-shaped discharge port attached to the device, and FIG. 6 is a conventional example. FIG. 7 is a perspective view of a conventional gas discharge nozzle. 11... Processing chamber, 12... Wafer (processed object), 13... Low pressure mercury lamp, 14...
...Gas storage chamber, 15...Nozzle, 16.
...03 generator, 17...wafer placement stand,
18.19...Piping, 2o...Motor. Name of agent: Patent attorney Toshio Nakao and 1 other person 1st
Figure 2 Figure 3 Figure 6 Figure 4 Figure 7

Claims (4)

[Claims] (1) In an apparatus that introduces an oxygen-containing gas into a processing chamber capable of heating a workpiece and irradiates the workpiece with ultraviolet rays to decompose and remove organic matter, the flow path of the oxygen-containing gas is at least 184.9nm and 253.7n
A processing device characterized in that it is made of an inorganic material that transmits ultraviolet rays of m. (2) The processing apparatus according to claim 1, wherein the gas containing oxygen is introduced into the processing chamber after passing through an ozone generator. (3) The gas flow path should have a gas reservoir between the ozone generator and the processing chamber, and should have at least 184.9 nm and 25 nm.
The processing apparatus according to claim 2, characterized in that the processing apparatus has a structure capable of irradiating ultraviolet rays of 3.7 nm. (4) In an apparatus that introduces an oxygen-containing gas into a processing chamber capable of heating a workpiece and irradiates the workpiece with ultraviolet rays to decompose and remove organic matter, the outlet for the oxygen-containing gas is , a nozzle having a slit shape or a plurality of pores, and the gas flow path and the nozzle are made of an inorganic material that transmits ultraviolet rays of at least 184.9 nm and 253.9 nm. Device.