JP2002256458A - Method and apparatus for etching - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method and an apparatus for etching, which can form a high definition pattern in high efficiency by inhibiting progress of side etching even in a refined pattern. SOLUTION: The method for etching an object EO to be etched includes; generating micro droplets ES of an etching liquid, which have a collision speed against the object EO of 30-300 m/second and particle sizes of 15-100 μm, by mixing the etching liquid EL with gas GS and spraying it from a 2-fluid nozzle N; blowing the micro droplets ES of the etching liquid to the object EO; making a separation distance d between the object and the 2-fluid nozzle N as 50-500 mm; and forming a pattern of a wiring part by etching an electroconductive layer along a pattern of a mask layer.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an etching method and an etching apparatus, and more particularly to an etching method and an etching method for forming a wiring portion by pattern-etching a conductive layer to be processed on a substrate in a process of manufacturing a printed wiring board. Related to the device.

[0002]

2. Description of the Related Art In recent years, with the demand for higher integration and higher functionality of semiconductor devices, the miniaturization of the element structure of semiconductor devices has been progressing. In response, demands for miniaturization of a printed wiring portion of a printed wiring board on which a semiconductor device is mounted are increasing, and research and development are being conducted.

As an etching method for forming a printed wiring portion having a fine pattern, a method using a nozzle that spreads in a cone shape or a flat cone (fan) shape has been widely practiced. Using a pump, an etching solution is sprayed through the above-described nozzle, and the obtained etching droplets are sprayed on a substrate having a copper foil formed on the surface. A resist film, which is a mask layer, is previously formed in a pattern on the copper foil, and the copper foil is patterned by contacting the copper foil that is not protected by the resist film with an etching solution.

[0004]

However, in the above-described etching method, when an etching solution is jetted from a conventional nozzle, an etching reaction occurs in a direction perpendicular to the direction in which the etching solution is sprayed. For this reason,
When the thickness of the layer to be etched such as copper foil becomes thicker than the pattern width with the miniaturization of the printed wiring part,
Compared to the portion etched in the direction of spraying the etchant, the portion etched in the direction perpendicular to the direction of spraying the etchant is relatively large, and in some cases, the entire layer to be etched is etched, The wiring pattern may not remain. The above-mentioned problem has the same tendency even when adjustment such as increasing the pressure for injecting the etching solution into the nozzle is performed.

In the conventional nozzle, the diameter of the etching droplet obtained by spraying the etching solution is large.
When the etching droplet is sprayed on the layer to be etched, it stays in a layered form on the surface of the layer to be etched. For example, in the processing of a fine wiring pattern having a pattern rule of 100 μm or less, an etching solution is used. The droplet cannot enter the pattern of the resist film on the layer to be etched, and it becomes difficult for the etching droplet to effectively act on the surface of the layer to be etched. That is, the fatigue liquid component of the etchant stays near the surface of the layer to be etched, and the new liquid component of the etchant reaches the surface of the layer to be etched only by diffusion. Therefore, the etching rate is reduced, and the etching rate in the direction in which the etching solution is sprayed is equal to the etching rate in the direction perpendicular to the direction in which the etching solution is sprayed. This makes it difficult to form a wiring pattern.

The present invention has been made in view of the above circumstances, and an object of the present invention is to suppress the progress of side etching to form a high-definition pattern even in the case of etching a pattern miniaturized to, for example, 100 μm or less. An object of the present invention is to provide an etching method which can be formed by etching and can increase the etching efficiency, and an etching apparatus which realizes this method.

[0007]

In order to achieve the above-mentioned object, an etching method according to the present invention comprises the steps of mixing an etching solution and a gas and jetting them from a two-fluid nozzle to generate fine droplets of the etching solution. And the separation distance between the object to be etched and the two-fluid nozzle is 50 to 500 mm,
Spraying fine droplets of the etching liquid on the etching target to etch the etching target.

In the etching method of the present invention, preferably, the speed of the fine droplets of the etching liquid when colliding with the object to be etched is 30 to 300 m / sec.

In the etching method of the present invention, preferably, the particle size of the fine droplets of the etching solution is 15 to 100.
μm.

In the etching method of the present invention, preferably, the object to be etched is a substrate having a conductive layer and a mask layer formed on a surface thereof, and the conductive layer is etched along a pattern of the mask layer. Thus, a wiring portion is formed in a pattern.

[0011] The etching method of the present invention preferably further includes a step of successively cleaning after the step of etching the object to be etched.

[0012] In the etching method of the present invention, preferably, a shield plate for shielding a component traveling obliquely from the injection port is provided near the injection port of the two-fluid nozzle during the injection from the two-fluid nozzle. I do.

In the etching method according to the present invention, preferably, a plurality of the two-fluid nozzles are used, and when ejected from the two-fluid nozzles, the fine droplets ejected from each of the two-fluid nozzles spread out in a fan-like shape. The two-fluid nozzles are arranged such that the ends of the range overlap each other.

According to the etching method of the present invention, the velocity of the fine droplets of the etching liquid at the time of colliding with the object to be etched is 30 to 300 m by mixing the etching liquid and the gas and jetting them from the two-fluid nozzle. / Second,
A fine droplet of an etchant having a particle size of 15 to 100 μm is generated, and then a separation distance between an etching object such as a substrate having a conductive layer and a mask layer formed on a surface thereof and a two-fluid nozzle is set to 50 to 500 mm. The etching target is etched, for example, by spraying fine droplets of an etchant on the etching target and etching the conductive layer along the pattern of the mask layer to pattern the wiring portion. After the etching, cleaning can be performed continuously.

According to the etching method of the present invention, by mixing the etchant and the gas and jetting the mixture from the two-fluid nozzle, it is possible to generate fine droplets of the etchant having a particle size of 15 to 100 μm, for example. it can. Thereby, even when etching a pattern miniaturized to, for example, 100 μm or less, it is possible to allow minute droplets of the etchant to enter the pattern. Furthermore, by setting the separation distance between the etching target and the two-fluid nozzle to be 50 to 500 mm, a minute droplet of the etching liquid is sprayed on the etching target with a kinetic energy of a predetermined value or more,
The liquid droplets that have already adhered can reach the surface of the object to be etched while being displaced, whereby the etching reaction can be effectively caused. As described above, it is possible to form a high-definition pattern by etching while suppressing the progress of side etching, and it is possible to increase the etching efficiency.

In order to achieve the above object, an etching apparatus according to the present invention is provided in an etching chamber, an etching solution supply source, a gas supply source, and an etching processing chamber, wherein the etching solution supply source and the gas A two-fluid nozzle connected by a pipe to a supply source, and a holding unit that holds the etching object so that a separation distance between the etching object and the two-fluid nozzle is in a range of 50 to 500 mm; The two-fluid nozzle mixes the etching solution and the gas to generate fine droplets of the etching solution,
Fine droplets of the etching liquid are sprayed on the etching target to etch the etching target.

In the etching apparatus of the present invention, preferably, the speed of the fine droplets of the etching liquid when colliding with the object to be etched is 30 to 300 m / sec.

In the etching apparatus of the present invention, preferably, the particle diameter of the fine droplets of the etching solution is 15 to 100.
μm.

Preferably, the etching apparatus of the present invention is configured such that a substrate having a conductive layer and a mask layer formed on a surface thereof is used as the etching target, and the conductive layer is etched along the pattern of the mask layer. The wiring part is formed in a pattern.

Preferably, the etching apparatus of the present invention further includes a cleaning chamber adjacent to the etching processing chamber, and transport means for transporting the object to be etched from the etching processing chamber to the cleaning chamber. The etching and cleaning of the etching target are performed continuously.

In the etching apparatus of the present invention, preferably, a shielding plate for shielding a component obliquely traveling from the injection port is disposed near the injection port of the two-fluid nozzle.

Preferably, the etching apparatus of the present invention has a plurality of the two-fluid nozzles, and the ends of the fan-shaped range in which the microdroplets ejected from the two-fluid nozzles spread overlap each other. Each of the two-fluid nozzles is disposed.

According to the etching apparatus of the present invention, by mixing the etching liquid and the gas and injecting them from the two-fluid nozzle, it is possible to generate fine droplets of the etching liquid having a particle diameter of 15 to 100 μm, for example. it can. Thereby, even when etching a pattern miniaturized to, for example, 100 μm or less, it is possible to allow minute droplets of the etchant to enter the pattern. Furthermore, by setting the separation distance between the etching target and the two-fluid nozzle to be 50 to 500 mm, a minute droplet of the etching liquid is sprayed on the etching target with a kinetic energy of a predetermined value or more,
The liquid droplets that have already adhered can reach the surface of the object to be etched while being displaced, whereby the etching reaction can be effectively caused. As described above, it is possible to form a high-definition pattern by etching while suppressing the progress of side etching, and to increase the etching efficiency.

[0024]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of an etching method and an etching apparatus according to the present embodiment will be described below with reference to the drawings.

First, a method for manufacturing a printed wiring board to which the etching method and the etching apparatus of the present embodiment are applied will be described with reference to the sectional view of FIG. First, as shown in FIG. 1A, a conductive layer 20 such as a copper foil is coated on both sides of an insulating substrate 10 made of a thermosetting resin such as an epoxy resin or another resin with a thickness of several to several tens μm. It is formed with a film thickness. The conductive layer 20 can be formed by any method such as bonding, plating, and vapor phase growth.

Next, as shown in FIG. 1B, a resist film is formed on the conductive layer 20 by a photolithography process, that is, by a dry film resist or spin coating or the like, pattern exposure is performed, and further development is performed. By performing the processing, a resist film 30 is pattern-formed on the conductive layer 20. The above process is performed on both surfaces of the substrate, and a resist film 30 is formed on the conductive layer 20 on both surfaces of the substrate 10.

Next, as shown in FIG.
Is etched using the resist film 30 as a mask with respect to the conductive layers 20 on both surfaces. That is, the conductive layer 20 is etched along the pattern of the resist film 30, and the wiring portion 2 is etched.
0a is patterned. The above-described etching treatment may be performed on both surfaces simultaneously or one surface at a time. Next, for example, the resist film is peeled off by a strong alkaline solution or an organic solvent treatment to obtain a desired printed wiring board.

The etching process for the conductive layer 20 using the resist film 30 as a mask is performed by using the etching apparatus and method according to the present embodiment. FIG. 2 is a schematic configuration diagram of the etching apparatus according to the present embodiment. A plurality of two-fluid nozzles N are arranged in the etching chamber ER of the etching apparatus according to the present embodiment. Each nozzle N is connected to the etching solution tank ET and a gas cylinder GB such as a compressor and an air cylinder by piping. A pump P and a filter F are provided in a pipe connected to the etching liquid tank ET. Further, a water supply section WS is connected to a pipe connected to the etching liquid tank ET, and the etching liquid EL and water in the etching liquid tank ET are mixed at a predetermined ratio and supplied to the nozzle N as needed. Is done.

The conductive layer 20 and the mask layer 3
The etching object EO such as the substrate 10 on which 0 is formed is held by a holder (not shown), and the spray ES of the etching liquid is jetted from the nozzle N to spray the etching liquid on the etching object EO. ES is blown. The nozzles N are arranged, for example, in two rows so as to face each other. For a flat etching object EO such as the substrate 10 on which the conductive layer 20 and the mask layer 30 are formed, It is configured so that the spray ES of the etching solution can be sprayed from both sides.

The fatigue solution used for the etching process is temporarily stored in a fatigue solution storage tank ST, subjected to a regeneration process in a regeneration tank RT, and supplied to the etching solution tank ET as a regeneration solution. Also, a newly prepared new liquid can be supplied. The fatigue liquid may be disposed of as a waste liquid without being regenerated. Further, for example, an overflow in the etching liquid tank ET is disposed as a waste liquid LW.

In the cleaning chamber WR provided adjacent to the etching chamber ER, a plurality of two-fluid nozzles N
Are provided in an array, and a hot water supply source H
W and gas cylinder GB are connected by pipes, respectively.

Water or hot water spray is sprayed from a nozzle N 'of the cleaning chamber WR, and is sprayed on the etching object EO held by a holder (not shown) to perform a cleaning process. Nozzle N 'need not be a two-fluid nozzle. The warm water used for the cleaning process is disposed as a waste liquid LW.

The etching chamber ER and the cleaning chamber WR are partially in communication with each other, and an etching object EO is transported by a transport mechanism (not shown), so that the etching process and the cleaning process are continuously performed.

FIG. 3 is an enlarged view of a nozzle portion which is a main portion in the etching processing chamber ER. The two-fluid nozzle N arranged and provided in the etching processing chamber ER is, for example, a flat cone-type two-fluid nozzle, and has an etching solution E
The pipe to which L is supplied and the pipe to which gas GS such as air is supplied are connected. Etching solution EL and gas G
By supplying S at a predetermined pressure, the etching solution EL and the gas GS are mixed in the nozzle N, and are ejected from the two-fluid nozzle ejection port to generate fine droplets of the etching solution, and the etching spreads in a flat cone shape. It becomes a liquid spray ES and is sprayed on the surface of the etching object EO.

In the etching apparatus according to the present embodiment, the distance d between the etching object EO and the two-fluid nozzle N is set to 50 to 500 mm. Separation distance d is 50m
m, the average droplet velocity is still 3
There is no problem if the speed is not more than 00 m / sec. However, since it is close to the nozzle, uniform etching over the entire desired etching region becomes difficult. If the separation distance d is larger than 500 mm, the driving force of the etching solution due to the gas pressure is lost, and the etching force becomes insufficient. For this reason, the etching time for etching a predetermined amount becomes long. Furthermore, since the etching liquid is sprayed over a wide area, it is difficult to perform uniform etching over the entire desired area, and the in-plane uniformity of the etching is lost.

Further, by adjusting the supply pressure of the etching liquid EL and the gas GS, etc., the etching object EO can be adjusted.
The velocity of the fine droplets of the etching liquid when colliding with the nozzles can be adjusted, and preferably, the jetting is performed at 30 to 300 m / sec. If the speed of the microdroplets when colliding with the etching target EO is lower than 30 m / sec, the etching force in the vertical direction due to the gas pressure and the ejected microdroplets displace the already attached droplets to remove the etching target. It becomes difficult to reach the object, which leads to progress of side etching and a decrease in etching efficiency. On the other hand, if the velocity of the microdroplets when colliding with the etching object EO is higher than 300 m / sec, uniformity of the etching rate distribution in the etching liquid jetting area cannot be obtained, and the etching liquid distribution inside and outside the etching liquid jetting area cannot be obtained. The difference in etching power becomes very large, and it becomes difficult to perform uniform etching over the entire desired etching region. Further, since the energy is too large, the resist is chipped or peeled.

By changing the supply pressure of the etching liquid EL and the gas GS, the particle diameter of the fine droplets of the etching liquid can be adjusted from the two-fluid nozzle, and is preferably adjusted to 15 to 100 μm. Inject. If the particle size of the ejected fine droplets is smaller than 15 μm, the vertical kinetic energy required to push out the already attached droplets and reach the etching target is insufficient, so that the side etching occurs and the etching time is reduced. It leads to lengthening.
If the diameter of the ejected fine droplet is larger than 100 μm, for example, it becomes difficult for the etching liquid droplet to enter the fine resist film pattern opening of 100 μm or less, and the etching liquid stays on the surface of the layer to be etched. And it becomes difficult to perform etching of a high-definition pattern, which also causes side etching and prolongs the etching time.

Further, by changing the supply pressure of the etching liquid EL and the gas GS, etc., the ejection pressure ejected from the two-fluid nozzle can be adjusted.
Inject to 0.3 MPa.

When the conductive layer to be etched is, for example, a copper foil, the etching solution used for the above etching is a ferric chloride solution (40 ° Baume) and hydrochloric acid (0.3 mol).
1 / l), the dissolved copper concentration was 45 g / l,
Further, the composition is made to contain predetermined additives as necessary.

According to the etching apparatus of the present embodiment and the etching method using the same, an etching solution and a gas are mixed and jetted from a two-fluid nozzle, so that the etching with a particle size of, for example, 15 to 100 μm is performed. Micro droplets of liquid can be generated. Thereby, for example, 100
Even in the etching of a pattern miniaturized to a size of μm or less, it is possible to allow minute droplets of an etchant to enter the pattern. Furthermore, by setting the separation distance between the etching target and the two-fluid nozzle to be 50 to 500 mm, the fine droplets of the etching liquid are sprayed on the etching target with a kinetic energy of a predetermined level or more, and the droplets that have already adhered are removed. It can reach the surface of the object to be etched while being displaced, thereby effectively causing an etching reaction. As described above, it is possible to form a high-definition pattern by etching while suppressing the progress of side etching, and it is possible to increase the etching efficiency.

Further, since the etching solution can be used efficiently, the circulation of the etching solution can be reduced.
Since the total liquid volume can be reduced, equipment such as a tank capacity can be reduced. Conventionally, since the reaction efficiency of the returned etching solution is low, it was not possible to regenerate the etching solution in the original state without replenishing an oxidizing agent in the regeneration of the etching solution as compared with when the reaction efficiency was high. In the embodiment, the oxidative regeneration can be effectively performed by the amount used, and the fee for using the chemical can be reduced.

(Modification 1) FIG. 4 shows an etching chamber E
It is an enlarged view of a modification of the nozzle part which is a main part in R. This is substantially the same as the nozzle unit shown in FIG. 3, except that a shield plate SD is provided in the vicinity of the injection port of the nozzle N.
The shield plate SD can shield a droplet component that travels obliquely from the ejection port of the nozzle N and that is perpendicular to the spraying direction. Thereby, the progress of the side etching can be further suppressed, the stagnation of the etchant on the surface of the layer to be etched is suppressed, and the etching efficiency is improved. Further, fine droplets can be generated by mixing with a gas, so that a fine pattern of 100 μm or less can be etched.

(Modification 2) FIG. 5 shows an etching chamber E
It is an enlarged view of a modification of the nozzle part which is a main part in R. A plurality of two-fluid nozzles of the flat cone type shown in FIG.
The nozzles are arranged such that the ends of the spray ES of the etching solution sprayed in a fan shape from the nozzles overlap each other. The end of the etching solution spray ES is a droplet component that travels obliquely from the injection port of the nozzle N and is perpendicular to the spraying direction, and this component collides with a component sprayed from an adjacent nozzle to spray. Droplet components perpendicular to the direction can be canceled. Thereby, the progress of side etching can be further suppressed.

Etching Test (Test No. 1) A copper foil having a thickness of 18 μm was formed on a substrate, and a spiral test pattern of L / S = 25/25 μm shown in a plan view in FIG. An etching test was performed in which a resist film was formed as a pattern and an etching treatment was performed under the following conditions. A plurality of spiral patterns were formed, and a region B where no pattern was formed was provided between the spiral patterns.

Nozzle types (A: two-fluid nozzle shown in FIG. 3, B: one-fluid nozzle shown in FIG. 7, C: two-fluid nozzle with shielding plate shown in FIG. 4) for samples Nos. 1-4 ,
Separation distance d (mm) between etching object and nozzle, etching liquid pressure (MPa), air pressure (MPa), flow rate (ml)
/ Min) was changed as shown in Table 1 below. Here, the one-fluid nozzle Na shown in FIG. 7 is, for example, a cone-shaped one-fluid nozzle, and is connected to a pipe to which the etching liquid EL is supplied. By supplying the etching liquid EL at a predetermined pressure, an etching liquid spray ES spreading in a cone shape from the nozzle orifice is formed, and the etching target E is etched.
It is sprayed on the surface of O.

FIG. 6B is a cross-sectional view when the copper foil on the substrate 10 is ideally etched into a spiral pattern. The bottom width and the top width of the copper foil pattern are the width of the resist film (25 μm). ). The evaluation of the etching test
Bottom width and the top width of the outermost periphery of the copper foil pattern W _out of the spiral pattern, the inner peripheral portion of the bottom width and the top width of copper foil pattern W _in, and, exposing a substrate in a region where the resist film is not formed The etching was performed until the etching time. The evaluation results are shown in Table 1 below.

Here, the outermost copper foil pattern W _out is
Since facing the region B which does not form a pattern, side etching is likely to occur than the copper foil pattern W _in the inner peripheral portion. Conversely, when the side etching takes shorter etching time so as not to generate in the outermost copper foil pattern W _out, etching of the copper foil pattern W _in the region of the inner peripheral portion is insufficient, the copper foil pattern W etching the rest of the copper foil is sometimes generated between _in. Therefore, it is preferable that both the outermost and inner peripheral patterns can be processed with high definition.

[0048]

[Table 1]

As can be seen from Table 1, when the one-fluid nozzle of sample No. 3 is used, the outermost pattern disappears due to side etching, and the side etching proceeds on the inner peripheral side, so that pattern processing with high definition is not possible. It turns out that you can't. Further, by using a two-fluid nozzle as in the case of sample numbers 1, 2, and 4, an improvement can be obtained as compared with the case of a one-fluid nozzle. In particular, the separation distance d between the object to be etched and the two-fluid nozzle is 100 mm for sample No. 1 rather than 500 mm for sample No. 2.
mm allows more precise pattern processing and a shorter etching time. By using a shielding plate as in Sample No. 4, the pattern can be further refined.

Etching test (Test Nos. 2 and 3) Nozzle type (A is the two-fluid nozzle shown in FIG. 3, B is the one-fluid nozzle shown in FIG. 7), the distance d (mm) between the nozzle to be etched and the nozzle, air The value of the pressure (MPa) was changed as shown in Table 2 below, and the average particle diameter (μm) and the average droplet velocity (m / sec) when colliding with the object to be etched were set in Table 2.
, And an etching time test and a resolution test were performed.

The etching time test was performed on the substrate at 35 μm.
To form a copper foil with a thickness of
It was measured as the time until the substrate was exposed.

In the resolution test, a copper foil having a thickness of 18 μm was formed on a substrate, and the L / S shown in the plan view of FIG.
A resist film having a spiral test pattern of 30/30 μm was formed, and the determination was made based on the resolution when etching was performed. In the table, ◎ indicates “very good”, ○ indicates “good”, and x indicates “bad”.

[0053]

[Table 2]

From Test No. 2, it can be seen that by changing the distance d between the etching object and the nozzle, the average droplet speed of the droplet when colliding with the substrate changes. When the droplet speed exceeded 300 m / sec, the resist film was peeled off, and a desired copper foil pattern could not be obtained. If the speed is lower than 30 m / sec, the etching time becomes longer, that is, the time until the substrate is exposed becomes longer.
Side etching proceeds. This is because the etching force in the direction perpendicular to the substrate weakens, and the etching proceeds isotropically. Therefore, the resolution is reduced.

Even if the distance d between the etching object and the nozzle is 50 mm or less, the average velocity of the droplets is 30 mm.
If it is 0 m / sec or less, there is no problem, but it is difficult to perform uniform etching over the entire desired etching region because it is close to the nozzle. Further, when the distance d between the etching object and the nozzle exceeds 500 mm, the spray area of the etching liquid becomes very wide. Therefore, the number of droplets per unit area, that is, the amount of the etching solution per unit area decreases, and the etching power becomes insufficient along with the decrease in the average speed.

Test No. 3 shows that when the air pressure is changed in the two-fluid nozzle (A), the average particle size changes. When the particle size is small, even if the average speed is 30 m / sec or more, the etching time becomes long, and the side etching occurs, so that the resolution is reduced. In the case of the one-fluid nozzle (B), the average speed was close to 30 m / sec, but since the particle diameter was 100 μm or more, the penetration of the etching solution into the resist film opening of 100 μm or less was obstructed, and The etching solution stays on the surface of the etching layer, and the etching in the fine pattern does not proceed in the direction perpendicular to the substrate, but the side etching proceeds.

Etching test (droplet speed and etching time)
The relationship between the etching times when the average droplet velocity of the droplets when colliding with the substrate was changed was examined. In the etching time test, a copper foil having a thickness of 35 μm was formed on a substrate, the entire surface was solidly etched, and the time was measured until the substrate was exposed. FIG. 8 shows the results.

When the average droplet velocity is in the range of 30 to 300 m / sec, the higher the droplet velocity, the shorter the etching time at a constant rate, but when the average droplet velocity falls below 30 m / sec, the etching time sharply decreases. become longer. For this reason, the side etching proceeds, and the resolution is reduced.

According to the various experiments described above, when the etching liquid is jetted using the two-fluid nozzle, the distance between the etching object and the nozzle is set in the range of 50 to 500 mm, and furthermore, the etching when colliding with the etching object is performed. It has been confirmed that it is preferable that the speed of the liquid microdroplets is set to 30 to 300 m / sec and the droplets are ejected so that the particle diameter becomes 15 to 100 μm.

The present invention is not limited to the above embodiment.
For example, the conductive layer to be etched is not limited to a copper foil, and can be applied to other conductive layers. Further, the gas guided to the two-fluid nozzle is not limited to air, but nitrogen gas or other inert gas can be used. In addition, various changes can be made without departing from the gist of the present invention.

[0061]

As described above, according to the etching method and the etching apparatus of the present invention, the etching liquid and the gas are mixed and jetted from the two-fluid nozzle, and the distance between the object to be etched and the two-fluid nozzle is reduced. In the state of 50 to 500 mm, by spraying fine droplets of the etching solution sprayed from the nozzle onto the etching target, for example, a particle diameter capable of entering a fine pattern of 100 μm or less is 15 to 100 μm. A microdroplet of an etchant is generated, and with a predetermined kinetic energy, the already attached droplet is pushed away to reach an etching target, thereby effectively causing an etching reaction. As a result, it is possible to increase the etching rate, improve the productivity, and suppress the progress of side etching to form a high-definition pattern by etching.

[Brief description of the drawings]

FIGS. 1A to 1C are cross-sectional views illustrating a manufacturing process of a method for manufacturing a printed wiring board. FIG. 1A illustrates a process until a conductive layer is formed, and FIG. 1B illustrates a process until a resist film is patterned. c) shows the steps up to the etching step for patterning the conductive layer.

FIG. 2 is a schematic diagram of an etching apparatus according to the embodiment.

FIG. 3 is an enlarged view of a nozzle portion, which is a main part in an etching chamber.

FIG. 4 is an enlarged view of a modified example of a nozzle portion which is a main part in an etching processing chamber.

FIG. 5 is an enlarged view of a modified example of a nozzle portion, which is a main part in an etching chamber.

FIG. 6 (a) is a plan view of a spiral test pattern formed in an embodiment, and FIG. 6 (b) is a cross-sectional view of a case where a copper foil is ideally etched in the spiral pattern.

FIG. 7 is an enlarged view of a conventional nozzle portion.

FIG. 8 is a diagram showing a result of examining a relationship between a droplet speed and an etching time in an etching test of an example.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 10 ... board | substrate, 20 ... conductive layer, 20a ... wiring layer, 30 ... resist film, EL ... etching liquid, EO ... etching object, ER ... etching chamber, ES ... etching liquid spray, ET ... etching liquid tank, F ... filter , GB ...
Gas cylinder, GS ... gas, HW ... hot water supply source, LW ... waste, N, Na ... nozzle, P ... pump, RT ... regeneration tank, SD ... shield plate, ST ... fatigue storage tank, W _in ... inner circumferential portion pattern , W _out ... outermost peripheral pattern, WR ... washing room, WS ... water supply source.

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Naoko Asakuma 6-35, Kita-Shinagawa, Shinagawa-ku, Tokyo Inside Sony Corporation (72) Inventor Hirohisa Amako 6-35, Kita-Shinagawa, Shinagawa-ku, Tokyo Sony Corporation F term (reference) 4K057 WA11 WB04 WG10 WK10 WM06 WM09 WN01 5E339 AB02 BC02 BD03 BE13 BE16 CC01 CD01 CE16 CE19 CG04

Claims (14)

[Claims] A step of mixing an etching solution and a gas and injecting them from a two-fluid nozzle to generate fine droplets of the etching solution;
Spraying fine droplets of the etching solution onto the object to be etched, and etching the object to be etched. 2. The etching method according to claim 1, wherein the speed of the fine droplets of the etching liquid when colliding with the object to be etched is 30 to 300 m / sec. 3. The method according to claim 1, wherein the fine droplets of the etching liquid have a particle diameter of 15
The etching method according to claim 1, wherein the thickness is set to 100 μm. 4. The method according to claim 1, wherein the object to be etched is a substrate having a conductive layer and a mask layer formed on a surface thereof, and the conductive layer is etched along the pattern of the mask layer to form a wiring portion. 2. The etching method according to 1. 5. The etching method according to claim 1, further comprising a step of continuously cleaning after the step of etching the etching target. 6. The method according to claim 6, wherein said two-fluid nozzle ejects said two-fluid nozzle.
The etching method according to claim 1, wherein a shielding plate that shields a component that proceeds obliquely from the injection port is disposed near the injection port of the fluid nozzle. 7. A method according to claim 7, wherein a plurality of said two fluid nozzles are used.
2. The two-fluid nozzles are arranged such that the ends of a fan-shaped range in which the microdroplets ejected from each of the two-fluid nozzles spread during the ejection from the fluid nozzles overlap with each other. 3.
3. The etching method according to 1. 8. An etching chamber, an etchant supply source, a gas supply source, a two-fluid nozzle disposed in the etching chamber and connected to the etchant supply source and the gas supply source by a pipe, The separation distance between the object to be etched and the two-fluid nozzle is 50
A holding unit for holding the object to be etched so as to be in a range of about 500 mm, and the two-fluid nozzle mixes the etching solution and the gas to generate fine droplets of the etching solution. An etching apparatus for spraying minute droplets of the etching solution on an object to etch the object. 9. The etching apparatus according to claim 8, wherein the speed of the fine droplets of the etching liquid when colliding with the object to be etched is 30 to 300 m / sec. 10. The fine droplet of the etching liquid has a particle size of 1
The etching apparatus according to claim 8, wherein the thickness is 5 to 100 m. 11. The wiring portion is patterned by etching the conductive layer along the pattern of the mask layer using the substrate having the conductive layer and the mask layer formed on the surface as the etching target. An etching apparatus as described in the above. 12. A cleaning chamber adjacent to the etching chamber, and transport means for transporting the etching object from the etching chamber to the cleaning chamber, wherein the etching and cleaning of the etching object are continuously performed. 9. The etching apparatus according to claim 8, wherein the etching is performed. 13. The etching apparatus according to claim 8, wherein a shielding plate for shielding a component traveling obliquely from the injection port is disposed near the injection port of the two-fluid nozzle. 14. A two-fluid nozzle having a plurality of two-fluid nozzles, wherein each of the two-fluid nozzles is arranged such that ends of a fan-shaped range in which microdroplets ejected from each of the two-fluid nozzles spread overlap each other. The etching apparatus according to claim 8, wherein: