JPH0684862A - Cleaning device - Google Patents

Abstract

PURPOSE:To obtain a thin flow layer of reaction gas by using reaction gas as the first gas so as to make it flow along the surface to be treated while making the second gas flow so as to form a laminar flow on the first gas in order to form a layer of the first gas into a thin film. CONSTITUTION:In a device decomposing a resist, which is an organic matter becoming unrequired after being used as a mask of the surface of a wafer for a semiconductor, into O2 and H2O by action of ultraviolet rays and ozones, the wafer 1, which is an object to be treated, is loaded on a stage 2 turnable and having a built-in heater by vacuum adsorption or the like. The gas supply ports 5, 6 supplying reaction gas 3, which is the first gas, (for instance, ozone gas) and the second gas 4 forming a narrow flow layer of reaction gas, are arranged. Thereby, finishing accuracy of the processed parts for mechanically setting up and and adjusting the thickness of a reaction gas flow layer can be made extremely severe.

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 the surface of wafers, liquid crystal substrates, etc. for manufacturing semiconductor devices.

[0002]

2. Description of the Related Art For example, an organic substance on a wafer is oxidized by utilizing the oxidizing action of ozone gas, and C is a component of the organic substance.
Alternatively, in the method of removing H by converting H into a volatile gas of CO ₂ or H ₂ O, in order to improve the removal performance, in order to thin the flow layer of the reaction gas such as ozone gas on the surface to be treated,
A mechanical method, for example, a method of reducing the gap between the surface of the object to be processed and another surface facing the surface has been adopted. The gap is, for example, 0.5 mm or less, preferably 0.2 mm
It was said that the degree was good.

However, securing the above-mentioned narrow gap over a wide surface has a drawback that the manufacturing cost is increased in terms of processing of device parts and assembly accuracy. In addition, it requires time to perform regular checks and adjustments in order to maintain a narrow gap when used at high temperatures for a long time.

[0004]

SUMMARY OF THE INVENTION An object of the present invention is to obtain a thin flow layer of the reaction gas as described above by an easy maintenance method.

[0005]

In order to achieve the above-mentioned object, the apparatus of the present invention uses a reaction gas as a first gas and makes it flow along the surface to be treated to form a thin layer of the first gas. A second gas to form a laminar flow over the first gas.

[0006]

In the supplied reaction gas, only the gas in the portion in contact with the surface to be cleaned is effectively acting for cleaning. This is because the mean free path is extremely short because the life of the reaction gas that has become active atoms is short. Therefore, if the layer of the supplied reaction gas on the surface to be treated is thick, most of the gas is wasted. Therefore, it is an efficient method of supplying the reaction gas to form the supply gas layer in a very thin state on the surface to be processed.

Therefore, as in the present invention, the reaction gas is used as the first gas, which is supplied onto the surface to be treated, and further the second gas is supplied so as to flow over the first gas. The second gas acts to suppress the first gas from above so as to prevent the diffusion of the first gas. Therefore, since the first reaction gas flows in a thin layer along the surface to be processed, the reaction gas effectively hits the surface to be processed and can be efficiently cleaned.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described with reference to FIG. The wafer 1 which is an object to be processed is cleaned in an apparatus for decomposing and removing a resist, which is an unnecessary organic substance after being used as a mask for the surface of a semiconductor wafer, into CO ₂ and H ₂ O by the action of ultraviolet rays and ozone. The stage 2 which is rotatable and has a built-in heater is mounted by vacuum suction or the like. The reaction gas 3 which is the first gas on the wafer 1 (for example,
Gas supply ports 5 and 6 for supplying the second gas 4 forming a narrow flow layer of the ozone gas) and the reaction gas are arranged.

The device 7 for supplying the two kinds of gas is composed of quartz which transmits ultraviolet rays. When the ultraviolet light source 9 is not needed, it may be made of ozone resistant metal. The distance between the surface 8 of the gas supply device 7 and the wafer 1, which is the object to be processed, is about several mm. The thickness h ₁ of the flow layer of the first gas flowing at a constant pressure and a constant flow rate is adjusted by adjusting the supply pressure and the flow rate of the second gas so as to satisfy a predetermined cleaning time and uniformity by experiments. The second gas is a gas different from the first gas such as nitrogen gas that transmits ultraviolet rays.

Ports 5, 6 for supplying gas to the surface of the object to be treated
The structure shown in FIGS. 2, 3 and 4 is relatively simple and effective. In the case of FIGS. 2 and 3, it is important that the mouth is not located at the center of rotation so that the object to be processed does not continue to be cooled by the supply gas. A perspective view of the gas supply device portion of the embodiment of FIG. 4 is shown in FIG.

The supplied gas and the gas generated by the reaction are exhausted through the exhaust duct 10, treated with residual ozone and the like by a gas treatment device 11 provided on the way, and then discharged.

[0012]

According to the present invention, the finishing accuracy of the machined parts is made extremely strict for the mechanical setting adjustment of the thickness of the reaction gas flow layer, and the fine adjustment is performed by the mechanical gauge contact during the assembly of the apparatus. The same effect can be obtained only by adjusting the pressure and flow rate of the supply gas, without the need for

[Brief description of drawings]

FIG. 1 is an explanatory diagram of a configuration of the present invention.

FIG. 2 is an explanatory diagram of a first example of a gas supply device of the present invention.

FIG. 3 is an explanatory diagram of a second example of the gas supply device of the present invention.

FIG. 4 is an explanatory view of a third example of the gas supply device of the invention.

FIG. 5 is a perspective view of a third example of the gas supply device of the present invention.

[Explanation of symbols]

1 ... Object to be processed (wafer), 2 ... Stage, 3 ... First gas, 4 ... Second gas, 5, 6 ... Gas supply port, 7 ... Gas supply device, 8 ... Supply device surface, 9 ... Ultraviolet light source, 10 ... Exhaust duct, 11 ... Gas treatment device.

Claims (1)

[Claims] 1. A flow layer of another gas for controlling the thickness of the flow layer of the active gas is provided on the flow layer of the active gas effective for cleaning on the surface to be cleaned. Cleaning device.