JPH03283535A - Wet washing apparatus - Google Patents

Abstract

PURPOSE:To execute effective washing by comprising an immersing type washing mechanism having an immersing tank for reserving liquid to immerse washing objects and an ultrasonic generating means to give ultrasonic vibration to the liquid in this immersing tank and a spray washing mechanism for spraying the liquid to such washing objects. CONSTITUTION:An water cassette 5 is first housed within a spray chamber 4 and a liquid for washing, for example, sulfuric acid solution is sprayed while rotating the wafer cassette 5. Thereafter, the valve mechanisms 9a, 9b are switched and another liquid for washing, for example, ammonia + chloric acid solution is sprayed while rotating the wafer cassette 5. Then, the wafer cassette 5 is taken out from the spray chamber 4 and is immersed into an immersing tank 12. In this case, the predetermined liquid, for example, ammonia solution is stored previously in the immersing tank 12. Under the condition that the wafer cassette 5 and a semiconductor wafer 6 are immersed into the liquid in the immersing take 12, ultrasonic vibration is transferred to the liquid in the immersing tank 12 from an ultrasonic wave generating mechanism 13 to realize effective washing through the chemical washing effect of a washing solution and physical washing effect of ultrasonic wave.

Description

[Detailed description of the invention] [Purpose of the invention] (Industrial application field) The present invention relates to a wet cleaning device.

(Prior Art) Conventionally, dry cleaning devices using a predetermined gas and wet cleaning devices using a predetermined liquid are known as cleaning devices for removing adherents from various objects.

Among these cleaning devices, conventional wet cleaning devices used for cleaning substrates such as semiconductor wafers include immersion type (
There are two types of cleaning equipment: dip-type cleaning equipment and spray-type cleaning equipment.

In the above-mentioned immersion type cleaning device, a plurality of immersion tanks are arranged horizontally and store cleaning liquids such as ammonia solution, sulfuric acid solution, and hydrofluoric acid solution, and rinsing liquids such as pure water. There is.

Then, a plurality of semiconductor wafers housed in wafer cassettes or the like are sequentially transported and immersed in these wafer cassettes into these immersion tanks by the transport mechanism for cleaning. Recently, the immersion tank is equipped with an ultrasonic generating mechanism that applies ultrasonic vibrations to the liquid stored in the immersion tank, and uses both the chemical cleaning effect of the cleaning liquid and the physical cleaning effect of ultrasonic waves to enhance the cleaning effect. There are many types of immersion cleaning equipment.

On the other hand, in a spray-type cleaning device, a nozzle for spraying the cleaning liquid and rinsing liquid as described above and a rotation mechanism for supporting and rotating the wafer cassette are installed in the spray chamber. It is being Then, the semiconductor wafer is housed in a spray chamber together with the wafer cassette, and while the wafer cassette (semiconductor wafer) is rotated, a predetermined liquid is sequentially sprayed to perform cleaning.

(Problem to be solved by the invention) However, in the conventional wet cleaning device described above,
There are the following problems.

That is, in the immersion type cleaning apparatus, as described above, it is necessary to arrange a plurality of immersion tanks in line according to the number of cleaning processes. However, deposits include various substances such as organic substances, metals, and oxides, and in order to efficiently remove these substances, it is necessary to use a cleaning liquid suitable for each deposit. For this reason, the number of cleaning steps increases, and some devices have, for example, 5 to 6 immersion tanks arranged side by side. Therefore, there is a problem in that the device becomes larger and the space factor worsens (occupied area increases).

In addition, in spray cleaning equipment, within one chamber,
Since multiple types of cleaning liquids or rinsing liquids can be supplied and multiple cleaning processes can be performed within one chamber, the apparatus can be made smaller. However, there is a problem that effective cleaning using ultrasonic vibration cannot be performed.

The present invention has been made in response to such conventional circumstances, and enables effective cleaning using ultrasonic vibration, and also improves the space factor by suppressing the increase in size of the device. The purpose of this invention is to provide a wet cleaning device that can achieve the following goals.

[Structure of the Invention] (Means for Solving the Problems) That is, the present invention provides a wet cleaning apparatus that performs cleaning by sequentially contacting a plurality of types of liquids to an object to be cleaned. An immersion cleaning mechanism comprising an immersion tank for storing a liquid, an ultrasonic generation means for applying ultrasonic vibration to the liquid in the immersion tank, and a spray cleaning mechanism for spraying the liquid onto the object to be cleaned. Features.

(Function) The wet cleaning apparatus of the present invention having the above configuration includes an immersion tank for storing liquid and an ultrasonic generation means for applying ultrasonic vibration to the liquid in the immersion tank, so as to immerse the object to be cleaned. and a spray cleaning mechanism that sprays liquid onto the object to be cleaned.

Therefore, the immersion cleaning mechanism allows effective cleaning using ultrasonic vibration.

In addition, since multiple cleaning processes can be performed with one spray cleaning mechanism, there is no need to provide a number of immersion tanks according to the number of processes, and the size of the equipment can be suppressed, improving the space factor. can be achieved.

(Example) Hereinafter, an example of the wet cleaning apparatus of the present invention will be described with reference to the drawings.

As shown in FIG. 1, the inside of the casing 1 of the wet cleaning device is
It is separated into a spray cleaning mechanism housing part 2 and an immersion cleaning mechanism housing part 3.

The spray cleaning mechanism housing section 2 accommodates a spray cleaning mechanism configured similarly to a well-known spray type cleaning device.

That is, a cylindrical spray chamber 4 is provided in the spray cleaning mechanism housing section 2, and is configured to accommodate a plurality of (for example, 25) semiconductor wafers 5 in the spray chamber 4. A rotation mechanism 7 is provided which supports the wafer cassette 6 and rotates the wafer cassette 6 by a motor as shown by the arrow in the figure.

Further, around this rotation mechanism 7, a plurality of spray nozzles 8a and 8b, for example, two spray nozzles, are provided. These spray nozzles 8a, 8b are supplied with a predetermined liquid via valve mechanisms 9a, 9b, such as a cleaning liquid such as an ammonia solution, a sulfuric acid solution, or a hydrofluoric acid solution, or a rinsing liquid such as pure water. The liquid storage section 10a and IQb are connected to each other. Furthermore, the spray nozzles 8a, 8b
A heater or a cooler may be provided to set the cleaning liquid to a predetermined temperature that is effective for cleaning.

In addition, a drain pipe 11 is provided at the bottom of the spray chamber 4.
is provided.

By selectively opening and closing the valve mechanism 9819b, a desired liquid can be sprayed from the spray nozzles 8a and 8b onto the semiconductor wafer 5 in the spray chamber 4.

Note that the number of the spray nozzles 8 a s 8 b , the valve mechanisms 9 as 9 b , the liquid storage portions 10 a and 10 b, etc. is set according to the number of liquids required for the cleaning process performed within the spray chamber 4 . In other words, in the above example,
Cleaning can be carried out using two types of liquids,
If three or four types of liquids are required, the number of mechanisms is set to three or four.

Further, the valve mechanisms 9a and 9b are opened and closed by a control mechanism (not shown) according to a preset program. Further, the liquid in the liquid storage parts 10a, 10b is supplied to the spray nozzles 8a, 8 by the gas pressure of an inert gas (for example, nitrogen gas) applied to the liquid storage parts 10a, 10b.
b.

On the other hand, an immersion tank 12 for storing a predetermined cleaning liquid or rinsing liquid as described above is provided in the immersion cleaning mechanism housing section 3. An ultrasonic generating mechanism 13 is provided that applies ultrasonic vibrations to the liquid stored therein.

Then, a plurality of semiconductor wafers 6 housed in a wafer cassette 5 or the like are immersed together with the wafer cassette 5 in this immersion bath 12, and the chemical cleaning effect of the cleaning liquid and the physical cleaning effect of the ultrasonic waves are used together. It is constructed so that effective cleaning can be carried out.

The cleaning liquid may be further provided with a heater or a cooler to enhance the cleaning effect, or the cleaning liquid may be supplied to the immersion tank at a desired temperature in advance.

In the wet cleaning apparatus of this embodiment having the above configuration, a wafer cassette 5 containing a plurality of semiconductor wafers 6 is transported by a transport robot (not shown) or the like.

For example, the wafer cassette 5 is first placed in the spray chamber 4, and while the wafer cassette 5 is being rotated, a cleaning liquid such as a sulfuric acid solution is sprayed onto the wafer cassette 5.

Thereafter, the valve mechanisms 9a and 9b are switched to spray another cleaning liquid, such as an ammonia-hydrochloric acid solution, while rotating the wafer cassette 5.

Thereafter, the wafer cassette 5 is carried out from the spray chamber 4 by a transport robot (not shown), and the wafer cassette 5 is transferred to the immersion tank 1.
Contained within 2. Note that a predetermined liquid, such as an ammonia solution, is stored in the immersion tank 12 in advance.

Then, with the wafer cassette 5 and the semiconductor wafer 6 immersed in the liquid in the immersion tank 12, the ultrasonic generation mechanism 13
Ultrasonic vibrations are applied to the liquid in the immersion tank 12, and effective cleaning is carried out by combining the chemical cleaning effect of the cleaning liquid and the physical cleaning effect of the ultrasonic waves.

In other words, in the wet cleaning apparatus of this embodiment having the above configuration, multiple cleaning processes using multiple types of liquids can be carried out in the spray chamber 4, so the number of immersions corresponding to the number of processes can be carried out. There is no need to provide a tank, the size of the device can be suppressed, and the space factor can be improved. Effective cleaning can be carried out using

In addition, in the above example, the case where cleaning was carried out using ultrasonic waves in the immersion tank 12 was explained, but for example, as a final cleaning step, immersing in the immersion tank 12 without using ultrasonic waves,
Cleaning is also effective.

This is because, for example, when spray cleaning is performed using a hydrofluoric acid solution or the like, a large amount of dust and the like may adhere to the semiconductor wafer 6.

Further, in the above embodiment, an example was described in which one spray cleaning mechanism and one immersion cleaning mechanism were provided, but the number of these mechanisms is appropriately set depending on the cleaning process.

[Effects of the Invention] As explained above, according to the wet cleaning device of the present invention, effective cleaning can be carried out using ultrasonic vibration, and space is saved by suppressing the device from becoming large. It is possible to improve the factor.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing the configuration of a wet cleaning device according to an embodiment of the present invention. DESCRIPTION OF SYMBOLS 1... Housing, 2... Spray cleaning mechanism housing part, 3... Immersion cleaning mechanism housing part, 4...
... Spray chamber, 5 ... Semiconductor wafer, 6 ... Wafer cassette, 7 ... Rotation mechanism, 8a, 8b ... Spray nozzle, 9a,
9b...Valve mechanism, 10a, 10b...
Liquid storage section, 11...Drain piping, 12...
... Immersion tank, 13... Ultrasonic generation mechanism. ] Figure

Claims (1)

[Claims] (1) In a wet cleaning device that cleans an object to be cleaned by sequentially contacting the object with a plurality of liquids, a dipping tank for storing the liquid and an overflow of the liquid in the dipping tank are used so that the object to be cleaned is immersed. A wet cleaning apparatus comprising: an immersion cleaning mechanism having an ultrasonic generating means for applying sonic vibration; and a spray cleaning mechanism that sprays the liquid onto the object to be cleaned.