JP5565673B2 - Mist etching apparatus and mist etching method - Google Patents

Description

  The present invention relates to a mist etching apparatus and a mist etching method in which an etching solution is misted and further vaporized to etch an object to be etched.

In general, in the manufacturing process of various electronic devices, an etching process is performed to form a wiring pattern.
In recent years, the wiring pattern tends to be miniaturized, and etching processing with a high aspect ratio independent of the density of the wiring pattern and the pattern shape is required.
In particular, indium tin oxide (ITO), which is widely used as a conductive thin film, zinc oxide (ZnO) and magnesium oxide (MgO), which are promising alternative materials for ITO, are required to have an etching method capable of forming a good pattern shape. ing.

  For the processing of electronic devices, dry etching such as plasma etching and ion milling, and wet etching such as dipping and spraying are used.

Wet etching can perform etching even on difficult-to-etch materials, but it is difficult to perform etching with high accuracy. In particular, zinc oxide (ZnO), magnesium oxide (MgO), and the like may be dissolved in a strong acidic or strong alkaline etching solution used for wet etching, so that it is difficult to optimize etching conditions with high accuracy. It is difficult to perform an etching process.
On the other hand, dry etching is a technique that provides high etching accuracy, but there are difficult-to-etch materials (metal materials, metal oxides, and the like) that are difficult to etch even when dry etching is used.

Patent Document 1 discloses an etching method that uses fine droplets formed by misting an etching solution.
The disclosed technique of Patent Document 1 is to etch a fine pattern by using an etching solution as a droplet of 10 μm or less. When this method is used, it is possible to perform an etching process even if the pattern gap is about 10 μm.
However, with the disclosed technique of Patent Document 1, etching processing is possible even with a fine wiring pattern, but it is difficult to obtain a good pattern shape. That is, since the misted etching solution is used for the etching process as droplets, the etching process surface cannot be smoothed or side etching cannot be prevented. Therefore, when applied to a material that is difficult to etch as described above, a good pattern shape cannot be formed.

JP 2007-036075 A

  The present invention has been made to solve the above-mentioned problems of the prior art, and can be applied to materials that are difficult to etch, suppress side etching, and have a smooth etching surface. An object of the present invention is to provide a mist etching apparatus and a mist etching method capable of obtaining a certain good pattern shape.

The invention according to claim 1 includes a mist generating unit that mists an etching solution and an etching unit that etches an object to be etched. The mist generating unit contains a mist and contains a mist. A mist generating mechanism that mists the etching solution, and a mist discharge port that discharges the generated mist to the outside of the mist generating container. The etching unit introduces mist into which the mist is introduced. The mist introduced from the mist introduction port, and a rectifying unit that rectifies the mist retained in the stagnation part, and the etching object is provided in the rectification unit, The present invention relates to a mist etching apparatus characterized in that the mist is vaporized in an etching section.

  The invention according to claim 2 relates to the mist etching apparatus according to claim 1, wherein a carrier gas introduction port for introducing a carrier gas for conveying the mist to the etching unit is provided in the mist generation unit.

  The invention according to claim 3 relates to the mist etching apparatus according to claim 2, wherein the etching portion is provided with an exhaust port through which the carrier gas is exhausted.

The invention according to claim 4 relates to the mist etching apparatus according to any one of claims 1 to 3 , wherein the rectifying unit is connected to the staying unit in a horizontal direction through a flow passage.

The invention according to claim 5 relates to the mist etching apparatus according to any one of claims 1 to 4 , wherein the mist is vaporized by the rectifying unit.

The invention according to claim 6 is the mist according to any one of claims 1 to 5 , wherein a space height of the rectifying unit is 0.1 to 5.0 mm above the etching object. The present invention relates to an etching apparatus.

The invention which concerns on Claim 7 is provided with the mist production | generation part which mists an etching liquid, and the etching part which etches an etching target object, The said mist production | generation part contains the etching liquid, and is mist which is mist-ized A mist generating mechanism that mists the etching solution, and a mist discharge port that discharges the generated mist to the outside of the mist generating container. The etching unit introduces mist into which the mist is introduced. etching and mouth, and a retaining portion for retention mist introduced from the mist inlet, a rectifier unit for rectifying the mist staying at該滞engaging portion, the mist rectified by rectifying section is vaporized The rectifying unit is connected to the vertically lower part of the staying unit via a flow passage, and the etching processing unit is connected to the vertical direction of the rectifying unit. It is provided with downwardly, on the characteristics and to Rumi strike etching apparatus in that the etching object is provided in the etching processing unit.

The invention according to claim 8 relates to the mist etching apparatus according to claim 7 , wherein the etching processing section is provided with scanning means capable of scanning the etching object in the horizontal direction of the processing section.

The invention according to claim 9 relates to the mist etching apparatus according to any one of claims 1 to 8 , wherein heating means for vaporizing the mist is provided in the vicinity of the object to be etched.

The invention according to claim 10 relates to the mist etching apparatus according to any one of claims 1 to 9 , wherein the mist generating mechanism is constituted by an ultrasonic vibrator or electrospray.

The invention according to claim 11 relates to the mist etching apparatus according to any one of claims 1 to 10 , wherein a dilution gas inlet for introducing a dilution gas for diluting the mist is provided separately from the carrier gas. .

The invention according to claim 12 mists an etching solution composed of an etching raw material made of hydrochloric acid (HCl) or a mixture of hydrochloric acid (HCl) and nitric acid (HNO ₃ ) and a solvent made of pure water, thereby reducing the Leidenfrost phenomenon. By using the mist as a droplet covered with a vapor film, the droplet covered with the vapor film is selected from zinc oxide (ZnO), zinc magnesium oxide (ZnMgO), and indium tin oxide (ITO). The present invention relates to a mist etching method characterized by performing an etching process on an etching target.
The invention according to claim 13 is characterized in that the mist is made to be a droplet covered with a vapor film by bringing the mist into contact with a surface heated to a temperature at which the Leidenfrost phenomenon occurs. The present invention relates to a mist etching method.
The invention according to claim 14 is characterized in that the mist is rectified into a droplet covered with a vapor film by passing the mist through a rectifying path heated to a temperature at which a Leidenfrost phenomenon occurs. The mist etching method according to claim 12 or 13.

The invention according to claim 15 relates to the mist etching method according to any one of claims 12 to 14 , wherein the mist is conveyed by a carrier gas.

The invention according to claim 16 relates to the mist etching method according to any one of claims 12 to 15 , wherein the etching solution is misted by ultrasonic vibration.

The invention according to claim 17 relates to the mist etching method according to any one of claims 12 to 16, wherein the mist is diluted with a diluent gas different from the carrier gas.

According to the first aspect of the present invention, the mist generation unit includes a mist generation unit that mists the etching solution and an etching unit that etches the object to be etched. The mist generation unit contains the etching solution and is misted. A mist generating container, a mist generating mechanism that mists the etching solution, and a mist discharge port that discharges the generated mist out of the mist generating container. The mist is introduced into the etching unit. The mist inlet and the object to be etched are provided, and the mist is vaporized in the etching portion, so that side etching is suppressed even for difficult-to-etch materials and the etching treatment surface is smooth. A pattern shape can be obtained, and there is a possibility that a reaction product due to etching may remain on the object to be etched. There. Therefore, it is possible to form a wiring pattern that does not cause an electrical short circuit or current leakage. In addition, since the etching solution is misted and the outermost layer of the mist particles is vaporized, an efficient etching process with a small amount of the etching solution is possible, and the waste amount of the etching solution can be reduced.
In addition, the etching unit includes a retention unit that retains the mist introduced from the mist introduction port, and a rectification unit that rectifies the mist retained in the retention unit, and the etching target includes the rectification unit. As a result, it is possible to prevent loss of mist such as dew condensation and adhering to the wall surface, and a uniform etching process can be performed.

  According to the invention which concerns on Claim 2, the carrier gas inlet which introduce | transduces the carrier gas which conveys the said mist to the said etching part in the said mist production | generation part is provided, and the produced | generated mist is efficiently made into an etching part. Can be transported.

  According to the third aspect of the present invention, since the etching port is provided with a discharge port through which the carrier gas is discharged, a reaction product generated during etching is discharged outside the etching unit. It is possible to prevent the reaction product from remaining on the product.

According to the fourth aspect of the present invention, the rectifying unit is connected via the flow passage in the horizontal direction of the staying portion, so that the mist passing through the flow passage or the mist in which the outermost layer is vaporized is further rectified. More uniform etching.

According to the invention which concerns on Claim 5 , the said mist is vaporized in the said rectification | straightening part, and more efficient and uniform etching is attained.

According to the invention which concerns on Claim 6, when the space height of the said rectification | straightening part is the height of 0.1-5.0 mm above the said etching target object, it harms the flow of the vaporized etching raw material. Therefore, the etching object can be etched more efficiently, and the etching raw material is reliably subjected to the etching process.

According to the invention which concerns on Claim 7 , It is provided with the mist production | generation part which mists an etching liquid, and the etching part which etches an etching target object, The said mist production | generation part accommodates an etching liquid and is mist-ized. A mist generating container, a mist generating mechanism that mists the etching solution, and a mist discharge port that discharges the generated mist to the outside of the mist generating container. The etching unit introduces the mist. A mist inlet, a staying part for retaining the mist introduced from the mist inlet, a rectifying part for rectifying the mist stayed in the staying part, and the mist rectified in the rectifying part are vaporized The rectifying unit is connected to the lower part in the vertical direction of the staying unit via a flow passage, and the etching processing unit is connected to the rectifying unit. It is provided directly below, and the etching object is provided in the etching processing section, so that it is possible to prevent mist loss such as condensation and adhere to the wall surface, and more effective etching processing. Can be applied.

According to the invention which concerns on Claim 8 , more uniform etching is attained by providing the said etching process part with the scanning means which can scan the said etching target object in the horizontal direction of this process part.

According to the ninth aspect of the present invention, since the heating means for vaporizing the mist is provided in the vicinity of the etching object, vaporization of the outermost layer of the mist particle is promoted, so that the droplet is directly etched. It will not adhere to. Therefore, the etching process surface of the etching object can be made smoother.

According to the invention which concerns on Claim 10 , while the said mist production | generation mechanism is comprised from an ultrasonic transducer | vibrator or an electrospray, while being able to efficiently mist an etching liquid, it is fine from nano order to micro order. Mist particles can be obtained.

According to the invention which concerns on Claim 11 , by providing the dilution gas inlet which introduce | transduces the dilution gas which dilutes the said mist separately from the said carrier gas, mist will be disperse | distributed by dilution gas, and between mists Adhesion is suppressed and a dispersed state can be maintained even when the mist is vaporized.

According to the inventions according to claims 12 to 14, the etching liquid composed of an etching raw material made of hydrochloric acid (HCl) or a mixture of hydrochloric acid (HCl) and nitric acid (HNO ₃ ) and a solvent made of pure water is misted. By utilizing the Leidenfrost phenomenon, the mist is formed into a droplet covered with a vapor film, and the droplet covered with the vapor film is used to form zinc oxide (ZnO), zinc magnesium oxide (ZnMgO), indium tin oxide (ITO). ) By etching the etching object selected from the above, it is possible to obtain a good pattern shape that suppresses side etching even for difficult-to-etch materials and has a smooth etched surface, and by etching. There is no possibility that the reaction product remains on the etching target. Therefore, it is possible to form a wiring pattern that does not cause an electrical short circuit or current leakage. In addition, since the etching solution is misted and further vaporized, an efficient etching process with a small amount of the etching solution can be performed, and the amount of the etching solution discarded can be reduced.
Further, since the vaporization of the outermost layer of the mist particles is promoted, the droplets do not directly adhere to the object to be etched. Therefore, the etching process surface of the etching object can be made smoother.
According to the invention of claim 14, the mist is rectified and formed into a droplet covered with a vapor film, so that condensation can be suppressed and loss of mist can be prevented and efficient etching can be performed. Processing is possible.

According to the fifteenth aspect of the present invention, the mist can be efficiently transported by transporting the mist with a carrier gas.

According to the invention of claim 16 , by making the etching solution mist by ultrasonic vibration, the etching solution can be efficiently misted, and a fine mist from nano order to micro order can be obtained. Can do.

According to the invention of claim 17 , by diluting the mist with a diluent gas different from the carrier gas, the mist is dispersed by the diluent gas, and adhesion of mists is suppressed, and the mist is The dispersed state can be maintained even when vaporized.

It is a schematic sectional drawing of the mist etching apparatus which concerns on this invention. It is a schematic diagram of mist etching according to the present invention, (a) is a diagram showing mist particles, (b) is a diagram when the outermost layer of mist particles is a vapor film, (c) is a diagram when mist particles are vapor. FIG. It is an enlarged view of the etching target object vicinity in the case of mist etching. It is a schematic sectional drawing which shows other embodiment of the mist etching apparatus which concerns on this invention. It is the schematic of the etching part of the mist etching apparatus which concerns on this invention, Comprising: (a) is a perspective view, (b) is sectional drawing. It is an expanded sectional view of the etching part of the mist etching apparatus which concerns on this invention. It is a figure which shows other embodiment in a mist etching apparatus provided with a retention part and a rectification | straightening part, Comprising: It is a schematic sectional drawing which shows only an etching part. It is the partial enlarged photograph of a wiring pattern, (a) is a resist pattern, (b) is after etching of Example 1, (c) is after etching of Example 2, (d) is after etching of Example 3. It is a photograph.

DESCRIPTION OF EMBODIMENTS Hereinafter, preferred embodiments of a mist etching apparatus and a mist etching method according to the present invention will be described with reference to the drawings.
FIG. 1 is a schematic sectional view of a mist etching apparatus according to the present invention.
The mist etching apparatus (1) according to the present invention includes a mist generating unit (2) that mists an etching solution and an etching unit (3) that etches a substrate and a thin film formed on the substrate. The mist generating part (2) and the etching part (3) are connected to each other by a connecting pipe (4).
The mist generating part (2) is provided with a mist generating container (5), and an etching solution (6) is accommodated in the mist generating container (5).

The etching solution (6) accommodated in the mist generating container (5) is composed of an etching raw material (solute) and a solvent, and is appropriately changed depending on the type of the etching object (7). For example, for zinc oxide (ZnO), zinc magnesium oxide (ZnMgO), indium tin oxide (ITO), etc., hydrochloric acid (HCl) or a mixture of hydrochloric acid (HCl) and nitric acid (HNO ₃ ) is used as an etching material. Etching solution (6) using pure water as a solvent can be used.

The etching solution (6) is misted by the mist generating mechanism (8) provided in the mist generating container (5). The mist generating mechanism (8) is not limited as long as the mist generating mechanism (8) can generate mist of the etching solution (6) and can generate mist that does not have a speed (that is, can stay in the space).
For example, as shown in FIGS. 1 and 4, an ultrasonic vibrator (81) is attached to the mist generation container (5), and the etching liquid (6) is made mist by applying ultrasonic vibration.
The position where the ultrasonic vibrator (81) is attached is not particularly limited as long as the ultrasonic vibration can be propagated to the etching solution (6), but it is provided at the bottom of the mist generating container (5) as shown in the illustrated example. The ultrasonic vibration can be efficiently propagated to the etching solution (6).
When the ultrasonic vibrator (81) is provided at the bottom of the mist generating container (5), the bottom of the mist generating container (5) is a sheet made of synthetic resin such as polyethylene, and the etching liquid (6 ) May be subjected to ultrasonic vibration. By doing so, ultrasonic vibration can be propagated to the etching solution (6) more effectively.

  When the ultrasonic vibrator (81) is used, the amount by which the etching solution (6) is mist is appropriately adjusted according to the amount of electric power applied to the ultrasonic vibrator (81).

The mist generating mechanism (8) is not particularly limited as long as it can generate fine droplets (mist particles) that do not have a velocity and can stay in the space. As the mist generating mechanism (8), in addition to the above-described ultrasonic vibrator (81), electrospray can be used (not shown).
When the ultrasonic vibrator (81) or the electrospray is used, fine mist particles of nano-order to micro-order size can be efficiently generated, and the generation amount of mist can be adjusted. Nano-order to micro-order mist particles generated by an ultrasonic vibrator (81), electrospray, or the like do not have a velocity, that is, can stay in the space, and thus can be rectified by applying a velocity.
It is also possible to produce the mist (9) using the spray method, but in this case, the mist particle size is larger than the particle size obtained by the above method, so the mist particle size is adjusted (miniaturized) by classification. And it is good also as a state which can stay in space.

  The etching solution (6) misted by the mist generation mechanism (8) is discharged from the mist discharge port (10) to the outside of the mist generation container (5) while remaining in the mist (9) form, and is connected via the connecting pipe (4). To the etching section (3).

Mist (9) produced | generated by the mist production | generation container (5) is conveyed by carrier gas. By using the carrier gas, the mist (9) is efficiently conveyed to the etching part (3).
The carrier gas is not particularly limited as long as it does not react with the etching raw material that is a component of the mist (9). For example, air (compressed air), nitrogen, argon, or the like is used, and the carrier gas is appropriately changed depending on the etching object (7). The
The carrier gas inlet (11) is preferably provided in the mist generating part (2), and more preferably provided above the liquid surface of the etching liquid (6). By doing so, the mist (9) produced | generated more efficiently will be conveyed.

The conveyed mist (9) passes through the mist inlet (12) and is introduced into the etching part (3).
An etching object (7) is installed in the etching section (3), and the etching object (7) is placed on the support base (13) and subjected to an etching process.
The etching part (3) is provided with a carrier gas discharge port (14) for discharging the carrier gas to the outside. By providing the carrier gas discharge port (14), the reaction product generated during the etching is discharged out of the etching section (3). Accordingly, it is possible to prevent the reaction product from remaining on the etching object (7).
The mist (9) introduced into the etching part (3) is vaporized and used for etching.

Here, the mechanism of mist etching in the present invention will be described in detail.
FIG. 2 is a schematic diagram of mist etching according to the present invention.
In the mist etching according to the present invention, the Leidenfrost principle is used.

As described above, the etching solution (6) is misted by the mist generation mechanism (8), and the mist (9) is a fine mist particle (91) of nano-order to micro-order size (see FIG. 2 (a)). It is composed of
The mist (9) generated by the mist generation mechanism (8) is subjected to etching after the mist particles (91) constituting the mist (9) are vaporized over time. That is, the outermost layer of mist particles (91) is first vaporized and becomes vapor over time. Therefore, the vapor film (92) and the vapor formed around the mist particles (91) are composed of the etching raw material.
When the outermost layer of the mist particles (91) is vaporized, the particle diameter of the mist particles (91) becomes smaller than that at the time of generation. That is, the vapor film (92) is formed around the mist particles (91). Since the vapor film (92) is made of an etching raw material, the etching object (7) can be etched.

The ratio of the vapor film (92) increases with time with respect to the mist particles (91). That is, as described above, the mist particles (91) become vapor over time.
When the etching object (7) is subjected to etching before the vapor film (92) is formed on the outermost layer of the mist particles (91) (see FIG. 2A), the mist particles (91) are directly etched. It adheres to the object (7). If it does so, the shape (spherical) trace of mist particle | grains (91) will remain in the etching target object (7) after an etching.

When the etching solution (6) is misted by the mist generation mechanism (8) (ultrasonic vibrator (81) or electrospray), fine mist particles of nano-order to micro-order size can be obtained, and the fineness of less than 10 μm It can also be applied to etching of various wiring patterns. However, particle marks of mist particles (91) remain and it is difficult to suppress side etching.
If the outermost layer of the mist particles (91) exists without being vaporized, there is a possibility that condensation or condensation occurs.
Therefore, in the present invention, the mist particles (91) are vaporized over time.
The outermost layer of the mist particles (91) is vaporized, and the mist particles (91) are vaporized over time, so that the etching raw material is transported to the etching target (7) without being aggregated and condensed. Is done. In addition, since the mist particles (91) do not directly contact the object to be etched (7) (see FIG. 3), the etching surface can be smoothed and a fine wiring pattern can be obtained without causing side etching. However, a good pattern shape can be formed. Furthermore, since the mist particles (91) are vaporized over time and the etching raw material (vapor film (92) or vapor) hits the etching object (7) from the start to the end of the etching process, the object to be etched is uniform. The object (7) can be etched.

If the mist particles (91) covered with the vapor film (92) or the vaporized mist particles (91) remain in the etching part (3), the etching raw material reacts in the gas phase, and the reaction product May occur.
When carrier gas is used, the remaining etching raw materials and reaction products can be removed. The carrier gas containing the remaining etching raw materials and reaction products is discharged out of the etching section (3) from the carrier gas discharge port (14).

The etching part (3) is preferably divided into a stay part (31) and a rectification part (32) as shown in FIGS.
The stay part (31) is connected to the mist inlet (12), and the rectification part (32) is connected to the stay part (31) in the horizontal direction via the flow passage (33).
The mist (9) introduced from the mist introduction port (12) is first retained in the retention part (31), and after being retained, is introduced into the rectification part (32). In this rectification unit (32), the mist (9) is rectified parallel to the surface of the etching object (7).
By providing the rectifying unit (32), the mist particles (91) and the vapor covered with the mist (9) or the vapor film (92) are rectified in parallel with the surface of the etching object (7), and are to be etched. The object (7) will be etched uniformly. Further, when the rectifying section (32) is connected to the staying section (31) through the flow passage (33), the rectifying section is further rectified, and the mist particles covered with the mist (9) or the vapor film (92). (91) Etching can be performed more uniformly without sticking to each other or causing condensation.

As shown in FIGS. 4 and 5, when the etching part (3) is divided into the stay part (31) and the rectifying part (32), the etching object (7) (and the support base (13)) is the rectifying part (32). Installed.
The mist (9) is preferably vaporized after passing through the flow passage (33) and being introduced into the rectification section (32). By vaporizing the mist (9) by the rectifying unit (32), the etching raw material can be efficiently used for the etching process. That is, since the mist particles (91) are vaporized and rectified with time in the rectifying unit (32), the time until the mist particles (91) are completely vaporized and the flow rate of the mist particles (91). It becomes possible to etch uniformly by the product of (that is, the distance through which the mist particles (91) flow).
The carrier gas discharge port (14) is provided in the rectification unit (32). By doing so, the etching raw material and reaction product which remain without being subjected to etching can be surely removed.

FIG. 6 is an enlarged cross-sectional view of the etching part (3), schematically showing the flow of mist (9).
The cross-sectional area (Si) of the flow passage (33) and the cross-sectional area (So) in the mist flow direction (arrow in FIG. 6) of the rectifying section (32) are preferably Si ≧ So. By doing so, the mist (9) dispersed in the staying part (31) can be rectified and introduced into the rectifying part (32) as shown in FIG. 6, and compared with the case where a rectifying plate or the like is used. Condensation is prevented and mist (9) does not adhere to the inner wall surface of staying part (31).
Further, even when a large amount of mist (9) is introduced into the staying part (31), the mist (9) can be rectified and there is no possibility that the mist (9) will aggregate.

It is preferable that the space height (h) of the rectifying unit (32) is slightly higher than the etching target (7). That is, the space of the rectification unit (32) into which the mist (9) is introduced is set narrower than the staying unit (31).
The space height (h) of the rectifying section (32) is preferably 0.1 to 5.0 mm from the etching object (7). When the height is within this range, an efficient etching process can be performed without impairing the flow of the vaporized etching raw material. That is, when the velocity is given to the mist (9) with a carrier gas or the like by setting the above height range, a laminar flow is generated.
Therefore, the mist (9) introduced to be less than 0.1 mm may be saturated in the rectification unit (32), and the flow of the vaporized etching raw material may be delayed. Although a large amount of mist (9) can be introduced, there is a possibility that a reaction product is generated by an etching raw material that is not subjected to an etching process and stays in the rectifying section (32), which is not preferable in any case.

FIG. 7 is a diagram showing another embodiment of the mist etching apparatus provided with a staying part and a rectifying part, and is a schematic cross-sectional view showing only the etching part.
In the present invention, the rectifying unit (32) is connected via the flow path (33) to the lower part of the staying part (31) in the vertical direction, and the etching processing part (34) is further provided to the lower part of the rectifying part (32) in the vertical direction. The structure provided may be used as the etching section (3). In addition, the retention part (31) and the rectification | straightening part (32) shown in FIG. 7 stand the etching part (3) shown in FIG. 5 (a) vertically with the rectification part (32) below.
The mist (9) introduced into the retention part (31) passes through the flow passage (33) and is introduced into the rectification part (32). The mist (9) rectified by the rectification unit (32) is introduced into the etching processing unit (34) from the mist inlet (35) and is vaporized by the etching processing unit (34).
With such a configuration, the mist particles (91) and the steam covered with the mist (9) or the vapor film (92) are rectified, and the etching raw material is sprayed on the etching object (7). Effective etching is possible. Moreover, since the flow of mist (9) becomes a curtain shape, a uniform etching process is possible with respect to the etching object (7).

In the configuration shown in FIG. 7, scanning means (not shown) that can scan the etching object (7) in the horizontal direction of the etching processing section (34) may be provided.
By providing the scanning means, a more uniform etching process can be performed over the entire etching object (7).

In the configuration described above, the cross-sectional area (Si) of the flow passage (33) and the cross-sectional area (So) in the mist flow direction (arrow in FIG. 7) of the rectifying section (32) are preferably Si ≧ So. By doing so, the mist (9) dispersed in the staying part (31) can be rectified and introduced into the rectifying part (32), and condensation is prevented as compared with the case where a rectifying plate or the like is used, Mist (9) does not adhere to the inner wall surface of stay part (31).
Further, even when a large amount of mist (9) is introduced into the staying part (31), the mist (9) can be rectified and there is no possibility that the mist (9) will aggregate.

The space height of the etching processing section (34), that is, the height (h _e ) from the etching object (7) to the inlet (35) is preferably 0.1 mm to 3.0 mm. When the height is within this range, when the mist (9) is vaporized, the etching raw material (vapor film (92) or vapor) can be efficiently used for the etching process.

In the present invention, a diluent gas for diluting the generated mist (9) may be introduced separately from the carrier gas.
The diluent gas is preferably introduced from the diluent gas inlet (15), and the diluent gas inlet (15) is preferably introduced into the connecting pipe (4) through which the generated mist (9) passes. By introducing the dilution gas, the mist (9) generated in the mist generating section (2) is diluted and conveyed while maintaining a dispersed state.
Accordingly, even when the mist (9) is vaporized, the etching raw material is in a dispersed state, and the etching object (7) can be uniformly etched.

As described above, the misted etchant (6) is further vaporized and used for etching.
The method for vaporizing the mist (9) is not particularly limited, and an etching raw material species to be vaporized after the mist is selected is selected, or a vaporizing means is provided in the etching part (3).

When providing a vaporization means, if mist (9) can be vaporized, it will not be limited. Examples of means for vaporizing the mist (9) include a method of vaporizing by heating or a method of vaporizing by plasma.
When the vaporizing means is installed, the heating means (131) and the plasma generating means (not shown) are provided in the vicinity of the etching object (7).

In the present invention, it is preferable to install a heating means (131). When the heating means (131) is used, vaporization of the mist (9) is promoted and the mist particles (9) are efficiently vaporized.
For example, a heater or the like is installed as the heating means (131).
The heating means (131) may be installed below or above the etching target (7), and is not particularly limited as long as the etching target (7) can be heated. In this invention, it is preferable to provide below etching object (7) (support stand (13)) (refer FIG.1, 4). By providing the heating means (131) below the etching object (7), the outermost layer of the mist particles (91) is vaporized immediately before the mist (9) adheres to the etching object (7). More efficient etching is possible. In addition, when the etching target (7) is placed on the support base (13), the etching target (7) is heated via the support base (13), so that the etching target (7) is thermally damaged. There is no fear.
Moreover, the temperature at the time of heating is suitably changed according to the kind of etching object (7) or etching liquid (6).

By providing the vaporizing means in this way, the mist (9) existing in the vicinity of the etching object (7) is heated and the mist (9) can be efficiently vaporized.
Therefore, the etching process can be performed without the mist (9) directly adhering to the etching object (7). Therefore, the etching process surface of the etching object (7) can be made smoother.

  A magnetic field or an electric field may be applied when performing an etching process on the etching object (7). By applying a magnetic field or an electric field, the direction of etching (isotropy, anisotropy) can be adjusted, and etching with higher accuracy becomes possible.

  The atmosphere during the above-described mist etching process is not particularly limited, and the etching object (7) can be subjected to the etching process under atmospheric pressure, reduced pressure, or increased pressure.

The mist etching apparatus having the above-described configuration (see FIGS. 1, 4 and 7) can be applied to a surface treatment apparatus (not shown) for modifying the substrate surface and a cleaning apparatus (not shown) for cleaning the substrate surface.
In the surface modification apparatus, the mist raw material type, the surface treatment conditions, and the like are set according to the substrate (material to be modified) to be modified. Also in the cleaning device, mist raw material types, cleaning conditions, and the like are set according to the substrate to be cleaned (the material to be cleaned).

Hereinafter, the effect of the present invention will be made clearer by showing examples of the mist etching apparatus and the mist etching method according to the present invention.
However, the present invention is not limited to the following examples.

Using the mist etching apparatus shown in FIG. 4, each thin film of zinc oxide (ZnO), zinc magnesium oxide (ZnMgO), and indium tin oxide (ITO) formed on the substrate was etched. Example 1 used ZnO as an etching target, Example 2 used ZnMgO as an etching target, and Example 3 used ITO as an etching target.
The thin films of Examples 1 to 3 were formed on a substrate (film thickness: 100 nm) by a sputtering method.
After the resist pattern was formed on each thin film, a mist etching process was performed under the conditions shown in Table 1. The etching time was 180 seconds in Example 1, 80 seconds in Example 2, and 300 seconds in Example 3. (Compressed) air was used for the carrier gas and diluent gas.
The results are shown in FIG.

Etching along the resist pattern was performed in any of Examples 1 to 3, and no residue was found on the substrate in any of the examples (see FIGS. 8B to 8D).
In addition, the etching rate is 33.3 nm / min in Example 1, 75 nm / min in Example 2, and 10 nm / min in Example 3, and an accurate etching process can be performed at a relatively fast rate. all right.
Since the droplet traces are not seen at the end of the pattern and are smooth, it can be seen that the misted etchant is used for etching after further vaporization.
Moreover, since the taper shape was also good, it was confirmed that no side etching occurred.

  From the above, when the mist etching apparatus and mist etching method according to the present invention are used, the etching surface can be etched uniformly and smoothly even in materials where optimization of etching conditions such as ZnO, ZnMgO, and ITO is difficult. It is possible to suppress side etching.

  The mist etching apparatus and the mist etching method according to the present invention are suitably used for fine processing on difficult-to-etch materials for which it is difficult to optimize etching processing conditions.

DESCRIPTION OF SYMBOLS 1 Mist etching apparatus 2 Mist production | generation part 3 Etch part 31 Stay part 32 Rectification part 33 Flow path 34 Etching process part 5 Mist production | generation container 6 Etching liquid 7 Etching object 8 Mist production mechanism 81 Ultrasonic vibrator 9 Mist 91 Mist particle 92 Vapor film 10 Mist outlet 11 Carrier gas inlet 12 Mist inlet 13 Support base 131 Heating means 14 Carrier gas outlet 15 Diluted gas inlet Si Flow passage cross-sectional area So Mist flow direction cross-sectional area h Rectifier height

Claims (17)

It has a mist generating part that mists the etching solution and an etching part that etches the etching target,
The mist generating unit includes a mist generating container in which an etching solution is stored and misted, a mist generating mechanism for misting the etching solution, and a mist discharge port for discharging the generated mist to the outside of the mist generating container. And consist of
The etching unit is composed of a mist introduction port through which the mist is introduced, a retention unit that retains the mist introduced from the mist introduction port, and a rectification unit that rectifies the mist retained in the retention unit, The mist etching apparatus, wherein the etching object is provided in the rectifying unit, and the mist is vaporized in the etching unit.   The mist etching apparatus according to claim 1, wherein a carrier gas introduction port for introducing a carrier gas for conveying the mist to the etching unit is provided in the mist generation unit.   The mist etching apparatus according to claim 2, wherein the etching unit is provided with a discharge port through which the carrier gas is discharged.   4. The mist etching apparatus according to claim 1, wherein the rectifying unit is connected to the staying unit in a horizontal direction via a flow passage. 5.   The mist etching apparatus according to claim 1, wherein the mist is vaporized by the rectifying unit.   6. The mist etching apparatus according to claim 1, wherein a space height of the rectifying unit is 0.1 to 5.0 mm above the object to be etched. It has a mist generating part that mists the etching solution and an etching part that etches the etching target,
The mist generating unit includes a mist generating container in which an etching solution is stored and misted, a mist generating mechanism for misting the etching solution, and a mist discharge port for discharging the generated mist to the outside of the mist generating container. And consist of
The etching unit includes a mist introduction port through which the mist is introduced, a retention unit that retains the mist introduced from the mist introduction port, a rectification unit that rectifies the mist retained in the retention unit, and the rectification The mist rectified in the part consists of an etching process part that is vaporized,
The rectifying unit is connected to the lower part in the vertical direction of the staying unit via a flow path,
The etching processing unit is provided vertically below the rectifying unit,
The mist etching apparatus, wherein the etching object is provided in the etching processing unit.   The mist etching apparatus according to claim 7, wherein the etching processing unit is provided with a scanning unit capable of scanning the object to be etched in a horizontal direction of the processing unit.   The mist etching apparatus according to any one of claims 1 to 8, wherein heating means for vaporizing the mist is provided in the vicinity of the object to be etched.   The mist etching apparatus according to claim 1, wherein the mist generation mechanism includes an ultrasonic vibrator or an electrospray.   The mist etching apparatus according to claim 1, further comprising a dilution gas introduction port for introducing a dilution gas for diluting the mist separately from the carrier gas. The mist is vaporized by using a Leidenfrost phenomenon by misting an etching solution composed of an etching raw material made of hydrochloric acid (HCl) or a mixture of hydrochloric acid (HCl) and nitric acid (HNO ₃ ) and a solvent made of pure water. A droplet covered with a film, and with the droplet covered with the vapor film, an etching target is selected from an etching object selected from zinc oxide (ZnO), zinc magnesium oxide (ZnMgO), and indium tin oxide (ITO). A mist etching method characterized by being applied.   13. The mist etching method according to claim 12, wherein the mist is brought into a droplet covered with a vapor film by bringing the mist into contact with a surface heated to a temperature at which a Leidenfrost phenomenon occurs.   14. The mist is rectified into a droplet covered with a vapor film by passing the mist through a rectifying path heated to a temperature at which a Leidenfrost phenomenon occurs. Mist etching method.   The mist etching method according to claim 12, wherein the mist is conveyed by a carrier gas.   The mist etching method according to claim 12, wherein the etching solution is misted by ultrasonic vibration.   The mist etching method according to claim 12, wherein the mist is diluted with a diluent gas different from the carrier gas.

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