JPH072996B2 - Photo-induced electrode reactor - Google Patents

Description

Description: FIELD OF THE INVENTION The present invention relates to a photoinduced electrode reaction device suitable for depositing a metal in a predetermined shape with high accuracy and reproducibility on an electrode surface of a metal, a semiconductor or the like. .

[Background of the Invention]

As a method of drawing a metal pattern on the surface of a conductive substrate, for example, Puip in J. Electrochem. Soc. 128 , 2539 (1981).
“Investigations of Las by pe, Acosta, von Gutfeld
ER Enhanced Electroplating Mechanisms ”, the use of photo-induced electrode reaction has been investigated. This method is a phenomenon in which the electrode reaction is remarkably accelerated in the light irradiation part of the electrode surface. The advantage of this method is that it can perform low-temperature and low-damage treatments.The condition for effectively utilizing the spatial selectivity of this method is to ensure that certain parts of the electrode surface are It is necessary for the light to reach and for the other part of the electrode surface not to be irradiated with unnecessary light due to scattering, etc. However, in the device configuration that has been conventionally used, bubbles are generated in the light irradiated part of the electrode surface. The above conditions are often not satisfied due to generation and adhesion, and the accuracy of the formed pattern and the reproducibility of the formed pattern when the same treatment is performed a plurality of times have not been sufficient.

[Object of the Invention]

An object of the present invention is to provide a photoinduced electrode reaction device capable of forming a metal pattern on a metal plate or a semiconductor substrate at a low temperature with low damage and with high accuracy and reproducibility.

[Outline of Invention]

In the present invention to achieve the above object, by configuring the photo-induced electrode reaction device to forcibly spray the electrolyte solution to the light-irradiated portion of the electrode surface, avoiding the adhesion of the bubbles described above, and high The feature is that the pattern can be formed with accuracy and reproducibility.

Example of Invention

Hereinafter, the device according to the present invention will be described with reference to the present embodiment.
FIG. 1 is a schematic diagram showing the configuration of an embodiment of the present invention. This apparatus has a reaction tank 1 and a separate solution tank 2, and these tanks 1 and 2 are filled with an electrode solution 3 when the apparatus is used. A pair of electrodes 4 and 5 are installed in the reaction tank 1, and a gas introduction pipe 6 for feeding a non-reactive purging gas such as nitrogen or argon into the electrolyte solution 3 in another solution tank 2. is set up. Therefore, this solution tank 2
Is referred to as a purging tank 2. Reaction tank 1 and purging tank 2
Are connected by a pipe 7 and a pipe 9 provided with a pump 8. The electrolyte solution 3 is transported from the purging tank 2 to the reaction tank 1 via the pipe 9 by the pump 8, and then returns to the purging tank 2 via the pipe 7. That is, the electrolyte solution 3 circulates between the reaction tank 1 and the purging tank 2. Reaction tank 1
Is provided with an optical window so that the surface of the cathode 4 made of a material such as metal or semiconductor can be irradiated with light 10 obtained from a laser or other light source. The tip portion 11 of the tube 9 on the side of the reaction chamber 1 has a nozzle shape, and is arranged so that the electrolyte solution 3 sent from the purging tank 2 can be sprayed onto the portion of the cathode 4 irradiated with the light 10. This part will be described later in detail. In FIG. 1, a light source for supplying the light 10 and an optical system incidental thereto, a device for applying a potential to the electrodes 4 and 5, a mechanism for moving the position of the light 10 irradiation portion on the cathode 4. The equipment for supplying a predetermined gas to the gas introduction pipe 6 is omitted.

In the device according to the present invention, only the portion where the light 10 on the cathode 4 is irradiated by the photo-induced electrode reaction in the electrolyte solution 3 containing ions of a metal such as nickel or copper as cations, The fact that metal precipitation as described above occurs is used. Therefore, the method of applying the potential to the electrodes 4 and 5, the wavelength and energy conditions of the light 10 with which the cathode 4 is irradiated, the composition of the electrolyte solution 3, and the like are different from the metal deposition rate by the photoinduced electrode reaction. It is set so that the rate at which a metal is deposited by an electrode reaction not involving light is negligible.

By flowing a non-reactive gas such as nitrogen or argon into the electrolyte solution 3 through the gas introduction pipe 6 in the purging tank, the amount of gas such as hydrogen or oxygen dissolved in the electrolyte solution 3 that affects the electrode reaction is reduced. To be done. Such an electrolyte solution 3
In order to improve the efficiency of the cleaning operation, the gas introduction pipe 6 has a large number of small openings at its tip, and the gas is ejected from this portion into the electrolyte solution 3 as a large number of small bubbles.

While the photo-induced reaction as described above is proceeding, as shown in FIG.
May occur and adhere. This is because other reaction proceeds at the same time as the metal deposition reaction, and a gaseous reaction product is generated in the cathode 4.
It is considered that the cause is that the generated gas is generated on the surface, or the temperature of the cathode 4 locally rises by the irradiated light 10, and the dissolved gas is vaporized and adhered to the surface of the cathode 4. As shown in FIG. 2, such bubbles 12 are
Not only does it prevent the light 10 from irradiating a predetermined portion of the cathode 4, but it also causes disorderly scattering of the light 10, and
There is also a problem in that even in a portion where 10 does not reach, a metal 13 is deposited due to a photo-induced electrode reaction due to scattered light. For example, light 10
When this device is used for the purpose of scanning and intermittently scanning the cathode 4 and drawing a metal pattern on the surface of the cathode 4, the bubbles 12 as described above are the cause of defects or blurring of the drawn pattern. Becomes The tip portion 11 of the tube 9 briefly described with reference to FIG.
The nozzle structure has a function of removing such adhered bubbles 12. FIG. 3 shows the tip of the pipe 9 in FIG.
FIG. 4 is a partial view showing a relative positional relationship among 11, a cathode 4 and irradiation light 10. The opening of the nozzle of the tip portion 11 is arranged near the portion of the cathode 4 to which the light 10 is irradiated, and the electrolyte solution 3 is set to jet to this portion. By purging,
Since the dissolved amount of the reactive gas in the electrolyte solution 3 is reduced, the generation of the bubbles 12 is suppressed. Further, even if the bubbles 12 are generated, they are quickly removed by the flow of the electrolyte solution 3.

FIG. 4 is a partial view showing another embodiment of the tip portion 11 of the tube 9. In this case, the optical window 15 is placed at a position facing the opening 14.
Is provided. The irradiation light 10 passes through the optical window 15 and enters the tip portion 11 of the tube 9 and the opening 14 from the same direction as the electrolyte solution 3.
Then, the cathode 4 is irradiated with the light. In this example, the irradiation light 10
And the flow of the electrolyte solution 3 ejected from the opening 14 to the cathode 4
Since it can be set perpendicularly to the surface of the cathode, the anisotropy of metal deposition on the cathode 4 surface due to the incident angle of the irradiation light 10 with respect to the cathode 4 surface and the flow direction of the electrolyte solution 3 is It doesn't matter. Further, there is an advantage that the electrolyte solution 3 is surely ejected from the opening 14 to the light 10 irradiation portion of the cathode 4. FIG. 5 shows the configuration of an embodiment which utilizes this advantage and is different from that described in FIG. In this embodiment, a storage tank 16 for an electrolyte solution 3 having an anode 5 therein, a tube 9 and a pump 8 for ejecting the electrolyte solution 3 to a cathode 4 via a tip portion 11 having an optical window 15 are provided. 17 for receiving the electrolyte solution 3 formed, a pump 18 for returning the electrolyte solution 3 received there to the storage tank 16 again, an electrode potential applying device
Composed of 19 mag. The anode 5 is a storage tank 16 for the electrolyte solution 3.
It is possible to install it at an arbitrary position between the tip part 11 of the pipe 9 and the pipe 9. The main black dots between this embodiment and the embodiment described with reference to FIG. 1 are that the cathode 4 is not submerged in the electrolyte solution 3 in the solution tank as shown in FIG. 5 in this embodiment, Only in the irradiated area of light 10 and a small area around it,
This is the point where the cathode 4 and the electrolyte solution 3 are in contact with each other. The advantage of the device having such a configuration is that the cathode 4 can be easily replaced, and the progress of unnecessary electrode reactions other than the portion irradiated with the light 10 can be suppressed. These advantages are suitable, for example, in the case of sequentially processing the cathodes 4 in which complicated patterns are already drawn. It is also possible to integrate the light source for supplying the light 10 and the optical system incidental to the light source with the tip portion 11 of the tube 9. If a movable tube 9 is used and a mechanism for moving the tip 11 in parallel with the cathode 4 is added, a metal pattern can be drawn on the cathode 4. A similar function is to use the cathode 4 at the tip 11
Needless to say, it can be realized also by a mechanism for moving in parallel with.

〔The invention's effect〕

According to the present invention, a metal pattern can be drawn with high reproducibility on a metal plate or a semiconductor substrate without heat treatment or treatment involving surface damage. Further, as compared with the method of covering the entire surface with a metal film and then removing the unnecessary portion of the metal to obtain a desired metal pattern, the method of the present invention can reduce the amount of wasted metal to a small amount. .

[Brief description of drawings]

FIG. 1 is a basic configuration diagram of an embodiment of the present invention, FIG. 2 is a schematic diagram for explaining a technical problem solved by the present invention, and FIG. 3 is a detailed diagram for explaining a part of FIG. FIG. 4 and FIG. 4 are diagrams for explaining another embodiment of the portion described in FIG. 3, and FIG. 5 is a basic configuration diagram of an embodiment different from the embodiment described with reference to FIG. 1 ... Reaction tank, 2 ... Purging tank, 3 ... Electrolyte solution, 4 ... Cathode, 5 ... Anode, 6 ... Gas inlet tube, 7,9
…… Tube, 8,18 …… Pump, 10 …… Irradiation light, 11 …… Tip of tube 9, 12 …… Bubbles, 13 …… Precipitated metal, 14 …… Aperture, 15
...... Optical window, 16 ・ ・ ・ Reservoir for electrolyte solution 3, 17 ・ ・ ・ Receptor for electrolyte solution 3, 19 ・ ・ ・ Electrode potential application device.

Claims (3)

[Claims] 1. A pair of electrodes, a means for applying a voltage between the electrodes, a means for irradiating a part of the electrodes with light, and a nozzle for forcibly spraying an electrolyte solution onto the light-irradiated parts of the electrodes. And a pump for ejecting an electrolyte solution from the nozzle, and a means for moving the position of the light irradiation portion of the electrode. 2. The photoinduced electrode reaction device according to claim 1, wherein the electrode irradiated with the light is one of a metal plate and a semiconductor substrate. 3. The light according to claim 1, wherein the electrolyte solution is held in a purging tank, and the purging tank has means for supplying a purging gas to the electrolyte solution. Inducing electrode reactor.