JPH05259139A - Cleaning apparatus - Google Patents

Abstract

PURPOSE:To achieve that a mixed gas which contains a definite amount of moisture in ozone gas is supplied stably to the surface of an object to be treated and to improve the cleaning performance of the title cleaning apparatus by a method wherein a vapor mixing device wherein gaseous water is mixed with a reaction gas which contains ozone and the mixture is supplied to the surface of the object to be treated is installed inside a container which houses an ultraviolet light source. CONSTITUTION:An organic substance is decomposed, gasified and removed by the action of ozone and ultraviolet rays. In such a cleaning apparatus, vapor mixing devices 1 to 4 wherein gaseous water is mixed with a reaction gas containing ozone and the mixture is supplied to the surface of an object 12 to be treated are provided inside a container 8 which houses an ultraviolet light source 7. For example, pure water is supplied, via a nozzle 2 by means of a fixed-quantity supply device, to a steam supply tank 2 to which ozone is supplied via a nozzle 1, and the temperature of the water at the inside is kept definite by means of a built-in heater. Steam which has been evaporated from the surface of the water in the steam supply tank 2 is supplied to a plurality of nozzles 5 in a mixed-gas branching pipe 4 by being carried by the air current of ozone.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for cleaning optical glass or glass for liquid crystals, for removing organic substances on a processed surface in the manufacture of semiconductor devices, and for removing and cleaning resist after being used as a mask.

[0002]

2. Description of the Related Art A technique for ashing and removing organic substances by using active oxygen atoms produced by decomposition of ozone is disclosed in, for example, Japanese Patent Laid-Open No. 58-15939.

In recent years, it has been desired to lower the temperature of the cleaning or organic substance removal treatment. That is, also in the ultra-miniaturized semiconductor device, it is indispensable to lower the processing temperature so as not to damage the liquid crystal substrate or the like using the chromium film. However, in the method of ashing an organic substance using active oxygen atoms formed by decomposition of ozone, the performance is strongly temperature-controlled, and for example, the removal of the resist film after being used as a mask in the manufacturing process of semiconductor devices. The processing temperature is 300 ° C to 250 ° C, 200
As the temperature decreases to ℃, it decreases to about 1/2 or 1/4. Under such circumstances, as a method of improving the removal performance by low-temperature treatment, it is known to supply water and ammonium nitrate together with ozone, as shown in JP-A-1-233728. However, in the above-mentioned publicly known example, the method of supplying water or the like is not considered, and water or the like is condensed in the pipe for introducing the mixed gas to the non-processed product, so that the mixed gas containing a certain amount of water cannot be stably supplied. There was a problem.

[0004]

SUMMARY OF THE INVENTION An object of the present invention is to improve the cleaning performance by stably supplying a mixed gas of ozone gas containing a certain amount of water to the surface of the object to be treated.

[0005]

The above object of the present invention is achieved by providing an apparatus for mixing ozone gas with water vapor in a container for accommodating an ultraviolet light source.

[0006]

Since the inside of the container for accommodating the ultraviolet light source is at a high temperature due to the radiant heat from the ultraviolet light source and the temperature is controlled, it is possible to reduce the ozone gas The mixed gas containing a certain amount of water can be stably supplied to the surface of the object to be processed without dew condensation of the mixed water vapor before being supplied to the object to be processed.

[0007]

EXAMPLE As a method of removing a resist film after it has been used as a mask on a wafer in the manufacture of a semiconductor device, ultraviolet rays and ozone are made to act on the resist at atmospheric pressure so that the organic resist is converted into CO ₂ , H An example of decomposing and removing gas such as ₂ O will be described. FIG. 1 is an explanatory diagram of one embodiment.

The raw material oxygen gas is made to flow in a narrow space between the double cylinders made of quartz, and the ozone generated by the ozone generator caused by the discharge between the double cylinders is introduced into the water vapor supply tank 2 by the nozzle 1. . Pure water is supplied to the steam supply tank 2 through a nozzle 3 by a constant quantity supply device, and the steam supply tank 2 has a built-in heater so as to keep the internal water temperature constant. The water vapor evaporated from the water surface of the water vapor supply tank 2 is supplied to the plurality of gas supply nozzles 5 of the mixed gas branch cylinder 4 along with the flow of ozone introduced into the water vapor supply tank. The plurality of gas supply nozzles 5 are welded through to the flat plate 6 of synthetic quartz, and the gas supply nozzles 5 are arranged so as to avoid the center of rotation and not be on the same rotation radius.

A low-pressure mercury discharge lamp 7 having a synthetic quartz tube as an arc tube, which is bent on a flat surface so that flat irradiation can be performed, is arranged on the nozzle arrangement side of a synthetic quartz flat plate 6. The low-pressure mercury discharge lamp 7 is housed in a lamp house 8 made of an aluminum alloy with an alumite finish. Nitrogen gas is introduced and replaced into the lamp house 8 through the nitrogen gas inlet 9 to prevent ozone from being generated around the low-pressure mercury discharge lamp 7 and to be controlled at a constant temperature. The surface of the synthetic quartz flat plate 6 opposite to the nozzle arrangement side is polished to a precise flatness. A stage 10 with a built-in heater that can be rotated and moved up and down is arranged below a synthetic quartz flat plate 6. A thin flat plate 11 made of quartz is arranged at the wafer mounting portion of the stage 10 to avoid direct contact between the wafer and the metal stage 10. In order to improve the adhesion of the wafer to the stage, the wafer is vacuum-sucked through a thin flat plate 11 made of quartz.

The loading and unloading of the wafer 12 onto the stage 10 is performed by the processing chamber 1 surrounding the stage.
3 is carried out by the transfer robot through the openable / closable transfer window 14 provided in one direction. At this time, the stage is vertically moved so that the wafer suction surface of the robot enters the back surface of the wafer. During processing, the reaction gas supplied from a plurality of gas supply nozzles is uniformly and rapidly passed over the wafer surface, and at the same time active oxygen atoms with a short lifetime are effectively given to the wafer surface. A gas flow gap for flowing a reaction gas between the flat plate and the synthetic quartz flat plate is controlled to be extremely small. The wafer 12 being processed receives the irradiation of ultraviolet rays and the supply of the reaction gas almost evenly while rotating by the stage. The processing chamber 13 is provided with an exhaust duct 15 for exhausting remaining ozone.

[0011]

According to the present invention, it is possible to stably cover a mixed gas containing a certain amount of water without providing a pipe heating device and without causing dew condensation before supplying the steam mixed with ozone gas to the object to be treated. Can be supplied to the surface of the processed material.

[Brief description of drawings]

FIG. 1 is a vertical sectional view of a cleaning apparatus according to an embodiment of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Nozzle, 2 ... Steam supply water tank, 3 ... Nozzle, 4 ... Mixed gas branch cylinder, 5 ... Gas supply nozzle, 6 ... Synthetic quartz flat plate, 7 ... Low-pressure mercury discharge lamp, 8 ... Lamp house, 9 ... Nitrogen gas Introducing port, 10 ... Stage, 11 ... Thin quartz plate, 12 ... Wafer, 13 ... Processing chamber, 14 ... Transfer window, 15
…duct.

Claims (1)

[Claims] 1. A cleaning device for decomposing and vaporizing and removing organic matter by the action of ozone and ultraviolet rays, for mixing gaseous water with a reaction gas containing ozone and supplying the same to the surface of the object to be treated. 2. A cleaning device, characterized in that the water vapor mixing device of (1) is provided in a container accommodating an ultraviolet light source.