JPH10242111A - Cleaning drying method and apparatus - Google Patents

Abstract

(57) [Problem] To perform a drying process without charging a semiconductor wafer after cleaning, and to reliably reduce defects due to static electricity such as adsorption of foreign substances and electrostatic breakdown of elements. SOLUTION: After a cleaning liquid for a semiconductor wafer W, nitrogen gas as a purge gas is ionized by an ionizer 9 connected to a gas supply pipe 11b and dried while spraying the semiconductor wafer W from a shower nozzle 6 to reduce nitrogen gas. Static electricity generated by friction with the semiconductor wafer W is prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for cleaning and drying, and more particularly to a technique effective when applied to a drying process after cleaning a semiconductor wafer.

[0002]

2. Description of the Related Art According to studies made by the present inventor, in a cleaning and drying step of a semiconductor wafer, drying after cleaning the semiconductor wafer is performed, for example, with an inert gas such as air or nitrogen (N ₂ ) gas. This is performed by so-called gas blowing, in which a certain purge gas is directly injected to the semiconductor wafer after cleaning.

After the drying process is completed, an ionizer neutralizing ions by using corona discharge in order to remove static electricity generated by friction between a gas blown during gas blowing and a semiconductor wafer. Of the semiconductor wafer is prevented from being charged.

[0004] As an example which describes this type of washing and drying apparatus in detail, see "Super LSI Manufacturing and Testing Apparatus Guidebook" published by the Industrial Research Institute on November 20, 1993, edited by Masashi Oshima (ed.). 1994 edition>"P115
ＰP120, and this document describes the structure and technical trends of the cleaning and drying apparatus.

[0005]

However, in the above-described semiconductor wafer drying technology in the washing and drying process,
The inventors have found the following problems.

That is, the static electricity generated on the semiconductor wafer during the gas blowing is in a charged state until the static elimination by the ionizer is completed.

An object of the present invention is to provide a cleaning and drying method and apparatus capable of performing a drying process without charging a semiconductor wafer after cleaning, thereby reliably reducing defects caused by static electricity such as foreign matter adsorption and element electrostatic destruction. To provide.

The above and other objects and novel features of the present invention will become apparent from the description of the present specification and the accompanying drawings.

[0009]

SUMMARY OF THE INVENTION Among the inventions disclosed in the present application, the outline of a representative one will be briefly described.
It is as follows.

That is, in the cleaning / drying method of the present invention, an ionized purge gas is blown onto the cleaned object to dry the object.

In the cleaning and drying method according to the present invention, the object to be processed is a semiconductor wafer or a part of a manufacturing apparatus.

The drying apparatus of the present invention further includes a drying chamber for performing a drying process on the object to be processed, a gas nozzle provided in the drying chamber, and for blowing a purge gas to the object to be processed.
The gas nozzle includes a gas supply unit that supplies a purge gas for drying the object to be cleaned after cleaning to the gas nozzle, and a gas ionization unit that ionizes the purge gas supplied from the gas supply unit to the gas nozzle.

Further, in the drying apparatus according to the present invention, the gas ionizing means comprises an ionizer.

Further, in the drying apparatus of the present invention, the object to be processed is a semiconductor wafer or a part of a manufacturing apparatus.

The cleaning / drying apparatus of the present invention is provided in a cleaning chamber for cleaning an object to be processed, and provided in the cleaning chamber.
A cleaning nozzle for spraying the cleaning liquid onto the object to be processed, a cleaning liquid supply means for supplying the cleaning liquid to the cleaning nozzle, an outlet for discharging the cleaning liquid ejected from the cleaning nozzle, and drying of the object after cleaning are performed. A drying chamber, a gas nozzle provided in the drying chamber, for blowing a purge gas to the object to be processed, a gas supply unit for supplying a purge gas for drying the object to be cleaned after cleaning to the gas nozzle, and a gas nozzle from the gas supply unit to the gas nozzle. And gas ionizing means for ionizing the supplied purge gas.

Further, in the cleaning / drying apparatus of the present invention, the gas ionizing means is constituted by an ionizer.

In the cleaning / drying apparatus of the present invention, the object to be processed is a semiconductor wafer or a part of a manufacturing apparatus.

As described above, the generation of static electricity due to the blowing of the purge gas can be prevented in the drying step after the cleaning of an object to be processed such as a semiconductor wafer. Defects due to static electricity can be reduced.

[0019]

Embodiments of the present invention will be described below in detail with reference to the drawings.

FIG. 1 is an explanatory diagram of a cleaning and drying apparatus according to one embodiment of the present invention, and FIG. 2 is an explanatory diagram of a cleaning and drying chamber according to one embodiment of the present invention.

In the present embodiment, a cleaning / drying apparatus 1 for cleaning a semiconductor wafer, which will be described later, and removing substances adhered to the surface thereof, comprises a cleaning / drying chamber (cleaning chamber, drying chamber) for cleaning / drying a semiconductor wafer. 2 are provided.

The cleaning and drying apparatus 1 includes a loader 3 for storing a semiconductor wafer before cleaning, an unloader 4 for storing a semiconductor wafer after cleaning, and a transport mechanism 5 for transporting the semiconductor wafer. It is provided near.

Further, the cleaning / drying apparatus 1 is of a batch type. As shown in FIG. 2, for example, about 50 semiconductor wafers W are set on a boat B made of quartz or the like, and this boat B is transported by the above-described transport mechanism. By moving by 5, insertion and withdrawal into the washing and drying chamber 2 are performed.

Next, a plurality of shower nozzles (washing nozzles, gas nozzles) 6 and an exhaust port 7 for reducing the pressure in the washing and drying chamber 2 by a vacuum pump are provided at a predetermined position in the upper portion of the washing and drying chamber 2. A waste liquid line (discharge port) 8 for discharging the cleaning liquid is provided at a lower portion of the cleaning and drying chamber 2.
Is provided.

Further, the cleaning / drying apparatus 1 includes an ionizer (gas ionizing means) 9 for utilizing corona discharge to ionize surrounding air into positive and negative directions and neutralize charges on the surface of the semiconductor wafer W with ions of opposite polarity. Gas supply unit (gas supply means) for supplying nitrogen gas as a purge gas for performing gas blowing
Further, a cleaning liquid supply unit (cleaning liquid supply means) for supplying a cleaning liquid is provided.

Further, the cleaning / drying apparatus 1 is provided with a switching valve 10 for switching between jetting the nitrogen gas supplied from the gas supply unit from the shower nozzle 6 and jetting the cleaning liquid supplied from the cleaning liquid supply unit. ing.

The shower nozzle 6 is connected to the output of the switching valve 10 by a pipe 11 and is connected to the switching valve 1.
0 is connected to a cleaning liquid supply pipe 11a connected to the aforementioned cleaning liquid supply section, and the other input section is connected to a gas supply pipe connected to the aforementioned gas supply section via an ionizer 9. 11b.

Next, the operation of the present embodiment will be described.

First, when the cleaning of the semiconductor wafer W with pure water is completed, the cleaning liquid is supplied from the cleaning liquid supply unit, and the cleaning liquid is sprayed from the shower nozzle 6 onto the semiconductor wafer in the form of powder.

Thereafter, the switching valve 10 is switched to start supplying nitrogen gas from the gas supply unit. The nitrogen gas is ionized by the ionizer 9 connected to the gas supply pipe 11b and is injected from the shower nozzle 6 as a nitrogen gas.

Thus, even if the nitrogen gas rubs against the surface of the semiconductor wafer W, the generation of static electricity can be prevented.

Next, when the gas blowing by the nitrogen gas is completed, the pressure in the washing and drying chamber 2 is reduced from the exhaust port 7 by a vacuum pump, thereby performing reduced pressure drying.

Then, the gas is blown again by the nitrogen gas ionized by the ionizer 9, and the washing and drying chamber 2 is blown.
Is returned to the atmospheric pressure, and the board B is transported by the transport mechanism 5 described above.
, And the semiconductor wafer W is transferred to a predetermined unloader 4.

Thus, in the present embodiment, the nitrogen gas ionized by the ionizer 9 is blown onto the semiconductor wafer W during the drying process, so that the semiconductor wafer W can be prevented from being charged by the gas blow, and foreign matter can be prevented. It is possible to reduce defects such as mixing and element electrostatic breakdown, and to improve the yield in the semiconductor manufacturing process.

In this embodiment, the semiconductor wafer W
The washing and drying chamber 2 (FIG. 2) for washing and drying the ionizer 9
Although FIG. 2 is provided, as shown in FIG. 3, for example, the ionizer 9 is provided on the loader 3 for storing the semiconductor wafer W before the cleaning and drying and the unloader 4 for storing the semiconductor wafer W after the cleaning and drying. A gas supply unit and a gas supply nozzle (gas nozzle) 12 may be provided.

In this case, similarly, for example, an inert gas such as nitrogen gas is ionized by the ionizer 9 and supplied from the gas supply nozzle 12 to the loader 3 and the unloader 4.
By setting the inside to an atmosphere of ionized nitrogen gas, charging of the semiconductor wafer W placed on the boat B can be prevented.

Further, in the present embodiment, the cleaning / drying chamber 2 is a single-tank type in which a plurality of cleaning and drying processes are performed in a single tank. Even if the ionization means such as the ionizer 9 is provided in the drying device performed by the drying chamber, the electrification of the semiconductor wafer W due to the gas blow can be prevented, and defects such as mixing of foreign matter and element electrostatic breakdown can be reduced. The yield in the semiconductor manufacturing process can be improved.

In this case, as shown in FIG. 4, the drying apparatus 13 is provided with a drying chamber 14 for performing a drying process on the semiconductor wafer W after cleaning, and a predetermined position above the drying chamber 14 is provided with a purge gas. Semiconductor wafer W placed on boat B
An exhaust port 7 for reducing the pressure inside the washing and drying chamber 2 by a gas nozzle 15 and a vacuum pump is provided.

The gas nozzle 15 is connected to a pipe 16, and the pipe 16 supplies a gas for supplying the above-described nitrogen gas through an ionizer (gas ionizing means) 17 for ionizing a purge gas such as a nitrogen gas for blowing. Connected to the means. In the drying process, when the purge gas is blown, the purge gas is ionized by the ionizer 17.

Although the invention made by the inventor has been specifically described based on the embodiments of the present invention, the present invention is not limited to the above embodiments, and various modifications may be made without departing from the gist of the invention. Needless to say, it can be changed.

For example, in the above-described embodiment, the cleaning and drying apparatus for cleaning and drying a semiconductor wafer has been described. Even if the blown purge gas is blown, it is possible to satisfactorily prevent electrification and reduce foreign substances and the like adhering to parts of the manufacturing apparatus.

In the above-described embodiment, the ionizer, which is a gas ionizer, is provided in the cleaning and drying apparatus for cleaning and drying the semiconductor wafer. By providing an ionizer in a vacuum apparatus for performing the above, and ionizing the purge gas in the vacuum processing, it is possible to prevent charging properly.

[0043]

Advantageous effects obtained by typical ones of the inventions disclosed by the present application will be briefly described as follows.
It is as follows.

(1) According to the present invention, the generation of static electricity in the drying process can be prevented by blowing the ionized purge gas to the object to be dried, and the adsorption of foreign substances can be reduced. Can be.

(2) Further, according to the present invention, in the drying process of the semiconductor wafer, the semiconductor wafer can be prevented from being charged by blowing the ionized purge gas to the semiconductor wafer, thereby adsorbing foreign substances on the semiconductor wafer and electrostatic charge of the device. Defects due to static electricity such as destruction can be reduced.

(3) Further, in the present invention, according to the above (1) and (2), the quality of products such as semiconductor devices can be improved, and the yield can be improved.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram of a cleaning / drying apparatus according to an embodiment of the present invention.

FIG. 2 is an explanatory diagram of a cleaning and drying chamber according to an embodiment of the present invention.

FIG. 3 is an explanatory diagram of a loader and an unloader provided with an ionizer according to another embodiment of the present invention.

FIG. 4 is an explanatory view of a drying apparatus provided with an ionizer according to another embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Washing-drying apparatus 2 Washing-drying room (washing room, drying room) 3 Loader 4 Unloader 5 Transport mechanism 6 Shower nozzle (washing nozzle, gas nozzle) 7 Exhaust port 8 Waste liquid line (discharge port) 9 Ionizer (gas ionization means) 10 Switching Valve 11 Pipe 11a Cleaning liquid supply pipe 11b Gas supply pipe 12 Gas supply nozzle (gas nozzle) 13 Drying device 14 Drying chamber 15 Gas nozzle 16 Pipe 17 Ionizer (gas ionization means) W Semiconductor wafer B Boat

Continued on the front page (72) Inventor Yoshikazu Tanabe 2326 Imai, Ome-shi, Tokyo Inside the Device Development Center, Hitachi, Ltd.

Claims (8)

[Claims] 1. A cleaning and drying method, wherein an ionized purge gas is blown onto an object to be cleaned after cleaning to dry the object to be processed. 2. The washing and drying method according to claim 1, wherein
A cleaning and drying method, wherein the object to be processed is a semiconductor wafer or a part of a manufacturing apparatus. 3. A drying apparatus for drying an object to be processed, comprising: a drying chamber in which a drying process of the object to be processed is performed; and a gas nozzle provided in the drying chamber and for blowing a purge gas to the object to be processed. A gas supply unit for supplying a purge gas for drying the object after cleaning to the gas nozzle, and a gas ionization unit for ionizing the purge gas supplied from the gas supply unit to the gas nozzle. apparatus. 4. The drying apparatus according to claim 3, wherein said gas ionizing means is an ionizer. 5. The drying apparatus according to claim 3, wherein the object to be processed is a semiconductor wafer or a part of a manufacturing apparatus. 6. A cleaning and drying apparatus for cleaning and drying an object to be processed, wherein the cleaning chamber is provided for cleaning the object to be processed and a cleaning chamber, and a cleaning liquid is sprayed on the object to be processed. A cleaning nozzle, a cleaning liquid supply unit for supplying the cleaning liquid to the cleaning nozzle, an outlet for discharging the cleaning liquid ejected from the cleaning nozzle, and a drying chamber in which the object to be processed after the cleaning is dried. A gas nozzle that is provided in the drying chamber and blows a purge gas to the object, a gas supply unit that supplies a purge gas for drying the object after cleaning to the gas nozzle, and a gas supply unit that supplies the gas nozzle from the gas supply unit. And a gas ionizing means for ionizing a purge gas to be purged. 7. The cleaning and drying apparatus according to claim 6, wherein
The cleaning and drying apparatus, wherein the gas ionization means is an ionizer. 8. The cleaning / drying apparatus according to claim 6, wherein the object to be processed is a semiconductor wafer or a part of a manufacturing apparatus.