JP2003245618A - Substrate washing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a substrate washing method for well washing a substrate in a shorter time by using an inexpensively furnished washing agent having no fear exerting adverse effect on the environment. <P>SOLUTION: Water 202 not subjected to treatment for dissolving chemicals or gas (hydrogen, ozone or the like) is put in a tank 201. A horn 106 entering this water 202 from the leading end thereof magnifies the vibration from a magnetostriction conversion element (vibrator) vibrated in high frequency to transmit the same. The printed circuit board 204 placed on the belt 203 passing along the bottom of the tank 201 is washed by cavitation generated by the vibration of the horn 106 and the large high speed flow of the water 202 going toward the printed circuit board 204 from the horn 106. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a technique for cleaning a substrate which is in the process of manufacturing a product such as a printed circuit board or a wafer.

[0002]

2. Description of the Related Art For example, a printed circuit board is manufactured through many steps, and various processes and processes are performed in the manufacturing process. Among the processing and processing, there are generated organic substances or metals that should be removed, such as cutting out material, punching processing, polishing processing, development processing to remove the unexposed part of the dry film laminated on the substrate, etc. Alternatively, some of them are targeted for the removal itself. Washing is done to remove such unwanted material.

[0003]

Conventionally, the cleaning of a printed circuit board in the manufacturing process is performed by a solvent or a chemical (chemical solution or drug) that dissolves the object to be removed on the printed circuit board.
Was carried out by using a solvent in which is dissolved in advance, ultrapure water (functional water) in which a specific gas (such as ozone and hydrogen) is dissolved, or a mixture thereof as a cleaning agent. In order to enhance the detergency, it has also been practiced to use ultrasonic irradiation by putting a vibrator inside a tank.

However, all such cleaning agents are expensive or require dedicated equipment for their production. Depending on what is dissolved in the cleaning agent, it is necessary to treat the cleaning agent after use so as not to adversely affect the environment. All of these increase the manufacturing cost. For this reason, it is important to use, as the cleaning agent, one that can be procured at a low price without adversely affecting the environment in order to suppress the manufacturing cost.

Even if a cleaning agent that is desirable in terms of environment and cost is used, if the cleaning cannot be performed well, or if the time required for the cleaning is longer, the use of such a cleaning agent has little significance. Become. Failure to perform good cleaning leads to deterioration of product quality, and longer cleaning time leads to higher manufacturing costs. Therefore, it is considered important to perform good cleaning without increasing the time required for cleaning.

An object of the present invention is to provide a substrate cleaning method for cleaning a substrate in a shorter time and favorably by using a cleaning agent which can be procured at a low cost and does not have a bad influence on the environment. .

[0007]

A substrate cleaning method of the present invention is a method used for cleaning a substrate in a manufacturing process, which is cleaning immediately after processing performed in the manufacturing process or during the manufacturing process. To perform the treatment, the substrate is placed in water that has not been treated to dissolve gas or chemicals, and the substrate placed in the water is opposed to a vibration medium that transmits the vibration generated by the vibrator. Then, the opposed vibration medium is vibrated by enlarging the amplitude of the vibration generated by the vibrator to clean the substrate.

The vibrating medium is composed of a vibrator 16
It is desirable to vibrate at a frequency within the range of k to 25 kHz. It is desirable that the distance between the substrate and the substrate is within a range of 3 to 5 mm and the substrate is vibrated. It is desirable that the substrate is washed while moving the vibrating medium and water relative to the substrate. .

In the present invention, the substrate to be cleaned in the manufacturing process is placed in water such as tap water which is not treated to dissolve gas or chemicals, and is opposed to the substrate placed in the water. The vibrating medium thus generated is vibrated by enlarging the amplitude of the vibration generated by the vibrator to clean the substrate.

When the amplitude of the vibration generated by the vibrator is expanded to vibrate the vibrating medium, the flow of water from the vibrating medium toward the substrate becomes larger and faster. By adding the flow to the cleaning force of cavitation generated by vibrating the vibrator (vibrating medium) at a high frequency,
A stronger detergency is realized. As a result, even if water that can be procured at a low price and that does not have a bad influence on the environment is used as the cleaning agent, the substrate can be cleaned satisfactorily in a shorter time.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a diagram showing an appearance of a vibration generator used for cleaning a substrate by the substrate cleaning method according to the present embodiment. The figure (a) is the front view, and the figure (b) is the side view.

As shown in FIGS. 1 (a) and 1 (b), the vibration generator 100 includes a vibration generating section 101 for generating vibration and a supporting section 10 for supporting the vibration generating section 101.
2 and a pedestal 103 to which the supporting portion 102 is attached
And are provided. Here, the vibration generator 1
01 for supplying cooling water, and its generation part 10
An operation panel and the like for controlling energization to 1 are omitted.

The vibration generating section 101 has a vibrating section 104 having a magnetostrictive conversion element for converting the electric current supplied from the oscillator of the operation panel into mechanical vibration of that frequency, and a cone 105 coupled to the conversion element. And a horn 106 connected to the cone 105.

The cone 105 and the horn 106
In both cases, the amplitude of vibration is expanded and transmitted.
As a result, the amplitude of the vibration generated in the magnetostrictive conversion element is expanded and transmitted by the cone 105 and the horn 106 so that the amplitude in the horn 106 becomes larger. The horn 106 is omitted in FIG.

One of the supporting portions 102 is a base 107 provided on the base 103, a column (column) 108 supported by the base 107, and is attached to the column 108.
An arm 109 for supporting the vibration generating unit 101 and an arm lock handle 110 for fixing the arm 109 to the column 108 are provided. As a result, the distance between the vibration generator 101 and the mount 103 is
The position can be adjusted by changing the position on the column 108 for fixing the arm 109.

Next, the vibration generator 1 having the above-mentioned structure.
A method of cleaning a substrate using 00 will be specifically described with reference to the explanatory diagram shown in FIG. Here, the substrate to be cleaned is the printed circuit board 204, and the surface to be cleaned is only one surface (upper side), but the other surface (lower side) is processed in the same manner after being inverted.

In FIG. 2, 201 is a printed circuit board 20.
4 is a tank installed on the pedestal 103 of the vibration generator 100 in order to clean the inside of the vibration generator 100. In the tank 201, a treatment for dissolving a chemical (medicine or chemical solution) or gas (hydrogen, ozone, etc.) is performed. It contains untreated water (for example, tap water or pure water) 202. A belt 203 on which a printed circuit board 204 is placed passes through the bottom of the tank 201. The horn 106 shown in FIG. 1 enters the water 202 from its tip by adjusting the fixing position of the arm 109.

The belt 203 is moved in the A direction indicated by the arrow in FIG. The horn 106 at least vibrates while the printed circuit board 204 mounted on the belt 203 faces it (for example, while there is an overlapping portion in the vertical direction). Thereby, the vibration is utilized to clean the printed circuit board 204, that is, to remove what should be removed.

The water 202 flows in the direction opposite to the A direction. This is to avoid that dirt that has separated from the printed circuit board 204 reattaches. By flowing the water 202 in such a direction, it becomes possible to perform better cleaning.

A high-frequency current is supplied from (an oscillator of) the operation panel to the magnetostrictive conversion element for generating the vibration transmitted to the horn 106. By vibrating the horn 106 at a high frequency in this way, it is possible to generate cavitation that exerts a strong cleaning power. It is concentrated on the tip of the horn 106.

Since the vibration from the magnetostrictive conversion element is transmitted to the horn (vibration medium) 106 via the cone 105, its amplitude is greatly expanded. When the amplitude is expanded, the horn 106 is printed on the printed circuit board 204.
The flow of water 202 towards is also larger and faster.
For this reason, such a flow of water 202 is added to the cleaning power by cavitation. As a result, a stronger cleaning power is realized over the entire portion facing the horn 106, avoiding the need to use solvents, chemicals or functional water. As a result, even if tap water or the like that can be procured at a low cost and does not have a bad influence on the environment is used as the cleaning agent, the printed circuit board 204 can be cleaned satisfactorily in a shorter time.

As a result of repeating the work of changing the frequency of the current supplied to the magnetostrictive transducer and confirming the state of the printed circuit board 204 after cleaning, it was found that good cleaning can be performed within the range of 16 kHz to 25 kHz. The distance d between the printed circuit board 204 and the horn 106 (see FIG. 2) is 3 to
It has been found that a range of 5 mm is suitable. It has been found that it is desirable that the output of the oscillator of the operation panel that supplies the current to the magnetostrictive conversion element is 500 W or more. From this, in particular, when removing dirt that is difficult to remove, of the frequency of the current supplied to the magnetostrictive conversion element, the distance d between the horn 106 and the printed circuit board 204, and the output of the oscillator. It is desirable that at least one of the above conditions satisfies the corresponding condition.

In the present embodiment, the object to be cleaned is the printed circuit board 204, but other kinds of substrates, for example, wafers may be objects to be cleaned. A member manufactured according to the shape of the substrate may be attached to the tip of the horn 106 to face the substrate to be cleaned.

[0024]

As described above, in the present invention, the substrate in the manufacturing process to be cleaned is put into water such as tap water which is not treated to dissolve gas or chemicals,
The vibrating medium facing the substrate placed in the water is vibrated by enlarging the amplitude of the vibration generated by the vibrator to clean the substrate.

When the amplitude of the vibration generated by the vibrator is expanded to vibrate the vibrating medium, the flow of water from the vibrating medium toward the substrate becomes larger and faster. By adding the flow to the cleaning force of cavitation generated by vibrating the vibrator (vibrating medium) at a high frequency,
A stronger detergency can be realized. For this reason, even if water that can be procured at a low cost and does not have a bad influence on the environment is used as the cleaning agent, the substrate can be cleaned satisfactorily in a shorter time.

[Brief description of drawings]

FIG. 1 is a diagram showing an appearance of a vibration generator used for cleaning a substrate by the substrate cleaning method according to the present embodiment.

FIG. 2 is a diagram illustrating a substrate cleaning method according to the present embodiment.

[Explanation of symbols]

100 vibration generator 101 Vibration generator 102 Support 103 mount 104 Vibration part 105 corn 106 horn 201 tank 202 water 204 printed circuit board

Claims (4)

[Claims] 1. A method used for cleaning a substrate in a manufacturing process, wherein the substrate is gas-cleaned for cleaning immediately after processing performed in the manufacturing process or for processing during the manufacturing process. Alternatively, it is placed in water that has not been subjected to a treatment for dissolving chemicals, a vibrating medium that transmits the vibration generated by the vibrator is opposed to the substrate that is placed in the water, and the opposed vibrating medium is A method of cleaning a substrate, characterized in that the amplitude of the vibration generated by the vibrator is expanded and vibrated to clean the substrate. 2. The vibrating medium is 16
The substrate cleaning method according to claim 1, wherein the substrate cleaning method vibrates at a frequency within a range of k to 25 kHz. 3. The substrate cleaning method according to claim 1, wherein the vibrating medium is vibrated with a distance from the substrate within a range of 3 to 5 mm. 4. The substrate cleaning method according to claim 1, wherein the substrate is cleaned while moving the vibrating medium and the water relative to the substrate. .