JP2003179009A - Polishing solution, polishing method, and polishing apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a polishing solution, polishing method and polishing apparatus, which can efficiently and inexpensively polish an excessive copper film deposited on a surface of a substrate, while preventing deterioration of the quality of a product. <P>SOLUTION: The polishing solution is used to polish a surface of a substrate on which a copper film is formed and the copper is embedded into fine recesses thereon. The solution contains one or more of water-soluble inorganic acid or salts thereof, water-soluble organic acid or salts thereof, and one or more of hydroxyquinolines. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a polishing liquid, a polishing method, and a polishing apparatus, and in particular, for forming a semiconductor device having a multilayer wiring structure, a wiring groove formed in an interlayer insulating layer is filled with a conductor such as copper. The present invention relates to a polishing liquid used for removing (polishing) excess copper and the like accumulated on a substrate when forming a buried wiring, and a polishing method and a polishing apparatus using the polishing liquid.

[0002]

2. Description of the Related Art In recent years, as a metal material for forming a wiring circuit on a semiconductor substrate, copper (Cu) having a low electric resistivity and a high electromigration resistance has been remarkably used in place of aluminum or an aluminum alloy. Has become. This kind of copper wiring is formed by depositing copper on almost the entire surface of the substrate by a method such as CVD, sputtering, and plating, and burying the copper inside the fine recesses provided on the surface of the substrate, and removing the excess copper by chemical mechanical. It is generally formed by a so-called damascene process, which is removed by polishing (CMP).

FIGS. 18 (a) to 18 (c) show an example of manufacturing a copper wiring board W of this kind in the order of steps. As shown in FIG. 18 (a), a semiconductor substrate 1 on which a semiconductor element is formed is formed. An insulating layer 2 made of a SiO ₂ oxide film or another low-k material is deposited on the upper conductive layer 1a, and inside the insulating layer 2, a contact hole 3 is formed by, for example, a lithography etching technique.
Then, a wiring groove 4 is formed, a barrier layer 5 made of TaN or the like is further formed thereon, and a seed layer 7 is further formed thereon as a power feeding layer for electrolytic plating. As the barrier layer 5, a Ta / TaN mixed layer, TiN, WN, SiTiN, CoWP, CoWB
Examples include membranes.

Then, as shown in FIG. 18B, the surface of the substrate W is plated with copper to fill the contact holes 3 and the wiring grooves 4 of the semiconductor substrate 1 with copper, and at the same time, to form an insulating layer. A copper film 6 is deposited on 2. Then, by chemical mechanical polishing (CMP), the copper film 6 on the insulating layer 2 is removed, and the surface of the copper film 6 filled in the contact hole 3 and the wiring groove 4 and the surface of the insulating layer 2 are almost removed. Make it on the same plane.
Thereby, as shown in FIG. 18C, the wiring made of the copper film 6 is formed.

[0005]

However, the damascene method is not yet a completed technique, and has many problems to be solved. That is, as described above, the insulating layer 2
After forming the wiring groove 4 and the like on the surface and depositing the barrier layer 5 and the seed layer 7 on the surface, in order to surely fill the inside of the wiring groove 4 and the like with copper metal, the surface of the insulating layer 2 is formed. Excessive copper film 6
Must be deposited, and at this time, irregularities are inevitably formed on the surface of the copper film 6. When the excessive copper film 6 is polished while being flattened, there are the following points to be improved.

If the polishing pressure is increased in order to increase the polishing rate, scratches, dishing, erosion, recesses, etc. are likely to occur on the copper surface after polishing, and the product quality is likely to deteriorate. Therefore, it is possible to increase the polishing rate. You can't do that, and you have to sacrifice productivity. In the future, it is expected that low-k materials having low hardness will be widely used as the insulating layer material, and if such low-k materials are used, this problem becomes more serious. The cost of the polishing slurry liquid (polishing liquid) used in the CMP step occupies a large specific weight, and it is desired to recover and reuse the polishing slurry liquid, but this is not easy to put into practical use with the current technology. Therefore, the amount of the polishing slurry discharged from the production line increases, which is not preferable for environmental protection.

The present invention has been made in view of the above, and is used for polishing an excessive copper film deposited on the surface of a substrate more efficiently and at a low cost while preventing deterioration of product quality. It is an object of the present invention to provide a polishing liquid, and a polishing method and a polishing apparatus using the polishing liquid.

[0008]

The invention according to claim 1 is a polishing liquid for forming a copper film on the surface and polishing the surface of a substrate having the copper embedded in fine recesses, which is water-soluble. The polishing liquid contains at least one inorganic acid or salt thereof, or at least one water-soluble organic acid or salt thereof, and at least one hydroxyquinoline.

As described above, when copper is used as an anode for electrolysis in a polishing liquid containing one or more hydroxyquinolines,
The copper and hydroxyquinoline react with the dissolution of copper to form an insoluble oxine copper film on the surface of copper without using an oxidizer whose concentration is difficult to control because of spontaneous decomposition. The reaction formula of copper and 8-hydroxyquinoline at this time is shown below.

[Chemical 1] This insoluble oxine copper is mechanically extremely fragile and is easily ground and removed by polishing using a polishing tool such as a polishing pad. In addition, it exhibits a relatively high electric resistance and suppresses the energization of the portion covered with oxine copper.

According to the second aspect of the present invention, the inorganic acid or its salt is a potassium salt or ammonium salt of an inorganic acid, and the organic acid or its salt is a potassium salt, ammonium salt, amine salt of an organic acid or The polishing liquid according to claim 1, which is a hydroxyamine salt. Examples of the inorganic acid include phosphoric acid, pyrophosphoric acid, sulfuric acid, nitric acid, sulfamic acid hydrochloride, hydrofluoric acid and the like. Further, as the organic acid, formic acid, acetic acid, propionic acid, oxalic acid, malonic acid, maleic acid, succinic acid, citric acid, gluconic acid, butyric acid, glycine, aminobenzoic acid,
Examples thereof include nicotinic acid and methanesulfonic acid. For example, a mixed acid in which two or more kinds such as hydrofluoric acid and nitric acid are added may be used.

The invention according to claim 3 is characterized in that the hydroxyquinolines are 2-hydroxyquinoline, 4-hydroxyquinoline, 5-hydroxyquinoline or 8-hydroxyquinoline.
It is the polishing liquid described. 8-Hydroxyquinoline is partly used as an industrial chemical, is easily available at a relatively low price, and is most suitable in terms of performance and price.

According to a fourth aspect of the present invention, the concentration of the water-soluble inorganic acid or salt thereof, or the water-soluble organic acid or salt thereof in the polishing liquid is 0.01 to 5.0 mol.
/ L and the conductivity of the polishing liquid is 0.5 to 100 m
It is S / cm, It is a polishing liquid in any one of Claim 1 thru | or 3 characterized by the above-mentioned. When the electrolytic current is 1 A / dm ² or more, it is preferable that the conductivity of the polishing liquid is 5 mS / cm or more.

The invention according to claim 5 is characterized in that the concentration of the hydroxyquinolines in the polishing liquid is 0.001 to 1.0% by weight. Polishing liquid. The concentration of the hydroxyquinolines in the polishing liquid is preferably 0.01 to 0.2% by weight, more preferably 0.05 to 0.2% by weight.

The invention according to claim 6 is one in which any one or more of benzotriazole or its derivative, benzimidazole or phenacetin as a corrosion and discoloration inhibitor for copper is used at a concentration of 0.001 to 0.5% by weight. The polishing liquid according to any one of claims 1 to 5, further comprising: When 100 mg / L or more of benzotriazole is added to a polishing liquid having a pH of 8 or more, a stable complex film is excessively formed on the surface of copper and oxine copper is prevented from being generated. Therefore, the type and concentration of the chemicals are appropriately selected according to the state of the polishing liquid.

The invention according to claim 7 is the polishing liquid according to any one of claims 1 to 6, characterized in that the pH of the polishing liquid is in the range of 3 to 11. PH of polishing liquid is 5
An insoluble oxine copper film is particularly likely to be produced in the region of ~ 9, and the thickness of the oxine copper film grows to a maximum of 1 mm. The pH of the polishing liquid can be selected according to the purpose and progress of the polishing process. That is, basically, the oxine copper film is used in the neutral region where the oxine copper film is most likely to be generated throughout the entire process. It is also possible to mainly remove electrolytic copper at a current density so as to quickly remove copper. In this case, it is preferable to add and use alkylene glycols or alkylene glycol alkyl ethers in order to increase the phosphoric acid concentration and enhance the smoothing effect. Further, in the final step of polishing, the pH of the polishing liquid can be lowered or raised in order to enhance the polishing selectivity of the barrier layer.

The invention according to claim 8 is the polishing liquid according to any one of claims 1 to 7, which contains a surfactant in a concentration of 0.001 to 0.1% by weight. As described above, by adding the nonionic surfactant, for example, polyoxyalkylene alkyl ether, excessive polishing of the insulating layer and copper can be suppressed, and the polishing rate of the remaining barrier layer can be increased. As this surfactant,
Considering comprehensively the selective polishing property, dispersibility of abrasive grains, water washability, and the effect on the subsequent processing steps, nonionic polyoxyethylene glycol alkyl ethers, polyoxyethylene / polyoxypropylene condensate , Acetylene glycols, ethylenediamine polyoxyalkylene glycol and the like are suitable.

In a ninth aspect of the present invention, when a copper film is formed on the surface and the surface of the substrate having the copper embedded in the fine recesses is polished, a water-soluble inorganic acid or a salt thereof, or a water-soluble inorganic acid is used. Surface of a substrate in a polishing liquid containing at least one organic acid or salt thereof and at least one hydroxyquinoline, and reacting with the hydroxyquinoline added to the polishing liquid to cause copper surface Is a combined electrochemical-chemical-mechanical polishing method for a polishing surface containing copper, which is characterized in that the oxine copper film produced in step 1 is simultaneously ground.

Thus, the insoluble oxine copper film formed on the surface of copper by the reaction of copper with hydroxyquinolines can be repeatedly ground and polished.
This oxine copper film shows a relatively high electric resistance, and the electric current to the part covered with this oxine copper film is suppressed,
It has a property that electric current is concentrated on a portion where the metal surface is exposed, and it is mechanically extremely fragile, and can be easily ground and removed by a polishing tool such as a rotating low-pressure polishing pad. Therefore, for example, in the damascene method of manufacturing a semiconductor substrate, when polishing an excessive copper film having irregularities on the surface of an insulating layer, while electrolyzing the copper surface as an anode in a polishing solution containing hydroxyquinolines, at the same time polishing the surface with a polishing pad. When polishing with a polishing tool such as, the oxine copper film formed on the copper surface is selectively ground and removed only on the convex portions, and current is concentrated on the exposed copper surface to immediately form the oxine copper film again. .. As a result, by continuing this operation while applying an effective current, it becomes possible to polish the copper film at a faster speed than in the conventional technique and while effectively planarizing.

According to a tenth aspect of the present invention, there is provided a polishing method according to the ninth aspect, characterized in that one of direct current and pulsed current, or a superposed current thereof is passed to carry out electrolytic polishing. According to the invention of claim 11, when electrolytic polishing is started,
Current density is 0.5 to 5.0 A / dm with respect to the surface area of copper
11. The polishing method according to claim 9, wherein the electrolytic polishing is performed by applying a current of ² .

According to a twelfth aspect of the present invention, a large number of anodes and cathodes are alternately arranged in the polishing liquid so as to face the copper film formed on the surface of the substrate and the cathodes are closer to the substrate than the anode. 10. A voltage is applied between the anode and the cathode to form the oxine copper film on the copper surface by the positive polarity of the copper surface generated by the bipolar phenomenon at this time. The polishing method according to any one of 1 to 11. As a result, for example, the excess copper film deposited on the surface of the substrate is removed, and the underlying layer such as the barrier layer is exposed, which allows uniform conduction of electricity from the external terminals such as electrical contacts to the copper film. Even when it is no longer possible, an oxine copper film can be formed on the copper surface by utilizing the bipolar phenomenon.

According to a thirteenth aspect of the present invention, the interelectrode resistance between the cathode and the anode in the polishing liquid is 10 to 10.
13. The polishing method according to claim 12, wherein the polishing voltage is 50 Ωcm, and the voltage applied between the cathode and the anode is 10 to 100V.

According to a fourteenth aspect of the present invention, there is provided a polishing apparatus for polishing a surface of a substrate in which a copper film is formed on the surface of the substrate and the copper is embedded in the fine recesses, and a water-soluble inorganic acid or a salt thereof,
Alternatively, electrolytic polishing using a polishing solution containing one or more kinds of water-soluble organic acids or salts thereof and one or more kinds of hydroxyquinolines, and the surface of copper by reacting with the hydroxyquinolines added to the polishing solution The polishing apparatus is characterized in that the oxine copper film produced in the above step is simultaneously ground.

According to a fifteenth aspect of the present invention, there is provided a substrate holding portion for holding the substrate downward, one or more kinds of water-soluble inorganic acids or salts thereof, or water-soluble organic acids or salts thereof, and hydroxyquinolines. A polishing tank containing a polishing solution containing at least one of the above, a cathode plate immersed in the polishing solution held in the polishing tank, and a polishing plate held in the polishing tank so as to face the cathode plate. A polishing apparatus having a polishing tool immersed in a liquid and arranged, and a relative movement mechanism for relatively moving the substrate held by the substrate holder and the polishing tool. The invention according to claim 16 is characterized in that the surface of the cathode plate is formed with a large number of grooves continuously extending over the entire length in the plane.
The polishing apparatus according to item 5. As a result, the polishing liquid can be supplied through the groove and the products, hydrogen gas, oxygen gas and the like can be discharged.

According to a seventeenth aspect of the present invention, there is provided a substrate holding part for holding a substrate, and one or more kinds of a water-soluble inorganic acid or a salt thereof, or a water-soluble organic acid or a salt thereof.
A polishing tank for holding a polishing liquid containing one or more kinds of hydroxyquinolines, and a plurality of anodes and cathodes are arranged alternately by insulating the cathodes closer to the substrate held by the substrate holding portion than the anodes. A plate, a power supply for applying a voltage between the anode and the cathode, a polishing tool disposed facing the electrode plate by being immersed in the polishing liquid, a substrate held by the substrate holding part, and the The polishing apparatus has a relative movement mechanism for relatively moving the polishing tool.

The invention according to claim 18 is characterized in that the surface of the electrode plate is provided with a large number of grooves extending in the plane over the entire length thereof. It is a device. The invention described in claim 19 is claim 1
The polishing apparatus according to claim 5 and the polishing apparatus according to claim 17 are arranged in a partitioned room in the same module, and the substrate is moved between the respective polishing apparatuses by a swing arm arranged in the module. Is a polishing apparatus.

[0026]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below. The polishing liquid of the present invention contains at least one or more water-soluble inorganic acids or salts thereof, or water-soluble organic acids or salts thereof, and one or more hydroxyquinolines. The properties, the action and effect of hydroxyquinolines in the polishing liquid, the configuration of the polishing apparatus used for polishing with the polishing liquid are explained in order, and the actual polishing with this polishing liquid is carried out. An example will be described.

[Composition and Properties of Polishing Liquid] The polishing of the present invention
As a water-soluble inorganic acid or salt contained in polishing fluid
Is phosphoric acid, pyrophosphoric acid, sulfuric acid, nitric acid, sulfamic acid hydrochloride
Inorganic acids such as acid and hydrofluoric acid, or these inorganic acids
Examples thereof include potassium salt and ammonium salt. Well
As the water-soluble organic acid or its salt, formic acid,
Acetic acid, propionic acid, oxalic acid, malonic acid, maleic acid, co
Succinic acid, citric acid, gluconic acid, butyric acid, glycine, ami
Organic compounds such as nobenzoic acid, nicotinic acid, and methanesulfonic acid
Acids or calunun salts of these organic acids, ammonium
Salt, alkylamine group or hydroalkylamine
Examples include salt. These are single or two or more types.
This water-soluble inorganic acid may be used as a mixed solution.
Or salt thereof, or water-soluble organic acid or salt thereof
Concentration (total concentration) is, for example, 0.01 to 5.0 mol /
It is L. The conductivity of the polishing liquid is, for example, 0.5 to 100 m.
Electrolysis current of 1 A / dm at S / cm ^TwoWhen doing the above,
It is preferably 5 mS / cm or more.

As the hydroxyquinolines, for example, one or more of 2-hydroxyquinoline, 4-hydroxyquinoline, 5-hydroxyquinoline and 8-hydroxyquinoline are used. Quinoline is the most suitable. The concentration is, for example, 0.001 to 1.0% by weight, preferably 0.0
It is 5 to 0.2% by weight. This 8-hydroxyquinoline is partially used as an industrial chemical, and can be easily obtained at a relatively low price.

Here, a water-soluble inorganic acid or its salt, or a water-soluble organic acid or its salt, and 8
When copper is electrolytically polished in a polishing solution containing -hydroxyquinoline using copper as an anode, copper is simultaneously dissolved and reacted with 8-hydroxyquinoline according to the above reaction formula to form insoluble oxine copper on the surface of copper. Copper grows into a scaly film as electrolysis continues. This oxine copper film has a high electric resistance and causes a rise in voltage, but when electrolysis is further continued, it drops off from the copper surface, and after this drop, new oxine copper is generated and repeatedly grows into a film.

The pH of the polishing liquid is used in a wide range of 3 to 11, for example, but an insoluble oxine copper film is particularly likely to be formed on the surface of copper by electrolytic polishing using copper as an anode in the polishing liquid. The pH range is 5 to 9, and the oxine copper film grows to a maximum thickness of 1 mm. PH of polishing liquid
Can be selected according to the purpose and progress of the polishing process. That is, basically, it is used in the neutral region where the oxine copper film is most likely to be formed throughout the entire process, but for example, in the previous stage where the entire surface of the insulating layer is covered with the copper film, the pH of the polishing liquid is lowered. It is also possible to rapidly remove copper mainly by electrolytic polishing at a high current density. In this case, it is preferable to add and use alkylene glycols or alkylene glycol alkyl ethers in order to increase the phosphoric acid concentration and enhance the smoothing effect. Further, in the final step of polishing, the pH of the polishing liquid can be lowered or raised in order to enhance the polishing selectivity of the barrier layer.

As a copper discoloration and corrosion inhibitor, benzotriazole or its derivative, benzimidazole, phenacetin, or the like is added to the polishing liquid, for example, 10 to 1000.
By adding at a concentration of mg / L, discoloration and corrosion of copper can be effectively prevented. However, when 100 mg / L or more of benzotriazole is added to a polishing liquid having a pH of 8 or more, a stable complex film is excessively formed on the copper surface,
The production of oxine copper can be prevented. Therefore, it is necessary to appropriately select the type and concentration of the chemicals according to the state of the polishing liquid.

By adding a surfactant to the polishing liquid, it is possible to suppress excessive polishing of the copper wiring buried in the insulating layer and the wiring groove and increase the polishing rate of the remaining barrier layer to increase the copper film. It can be suitable for the final step of polishing. In this case, non-ionic polyoxyethylene glycol alkyl ethers, polyoxyethylene polyoxy, polyoxyethylene polyoxy Surfactants such as propylene condensates, acetylenic glycols, ethylenediamine polyoxyalkylene glycols are suitable.

As the abrasive grains contained in the polishing liquid, alumina, colloidal silica, or a combination of alumina and colloidal silica is preferably used in the former step for the purpose of polishing copper, and the latter step. Colloidal silica is preferably used for polishing including the barrier layer.

Further, for example, when the thickness of the excess copper film deposited on the insulating layer is thicker than 1000 nm,
Uses a polishing liquid that does not contain abrasive grains, contains phosphoric acid and alkylene glycols, and has a large polarization effect on the copper surface during electrolysis, and electrolytically polishes at a current of 3 A / dm ² or more,
It is also efficient to polish most of the excess copper film at a high speed. The property of this polishing liquid is little changed due to the mixing of copper into the polishing liquid. By collecting the drainage liquid from the polishing device, filtering it, and adjusting the concentration, the process for reuse can be rationalized.

[Action and Effect of Hydroxyquinoline in Polishing Liquid] As a conductive component, ammonium oxalate: 1
0 g / L, glycine: 10 g / L, phosphoric acid: 30 g / L
Is added to pure water to dissolve it, ammonia water is added, and p
H was adjusted to 8.5, and then 8-hydroxyquinoline: 2 g / L was added and dissolved to prepare a polishing liquid. When the temperature of this polishing liquid was kept at 25 ° C. and a copper foil sample obtained by bright copper sulfate plating was dipped in the polishing liquid, a pale yellowish green oxine copper was produced on the copper foil surface. Preliminarily weighed multiple copper foil specimens were dipped in the polishing liquid, pulled up one by one at regular intervals, wiped off the oxine copper film on the surface, washed with water, dried and weighed to determine the weight loss of the copper foil. . The result is shown in FIG. It can be seen from FIG. 1 that copper gradually dissolves in the polishing liquid to form oxine copper, but the dissolution of copper almost stops when the surface of copper is covered with the film of oxine copper after a few minutes.

A pair of copper foils are used as an anode and a cathode, facing each other and immersed in the same polishing liquid as described above, and a voltage is applied between both electrodes from a DC power source (rectifier) to 3 A / dm.
A constant current of ² was applied. The result of measuring the voltage between both electrodes at this time is shown in FIG. From FIG. 2, it can be seen that the voltage is initially applied at a low voltage, but when a film of oxine copper is formed on the surface of the copper, the resistance gradually increases, and after a few minutes, the voltage becomes almost twice the initial voltage. .

The same experiment as in the previous section was conducted by setting the voltage between both electrodes to 5.
It was electrolyzed while keeping constant at 0V. FIG. 3 shows the results of measuring the change in the current and the weight loss of the copper foil at this time with time. From FIG. 3, a current of 4 A / dm ² initially flowed, but the current decreased with time, and after a few minutes, the initial 1
It can be seen that the amount becomes less than or equal to / 2, and that the reduction amount of the copper foil substantially matches the energization amount.

Further, it has been confirmed that the oxine copper film formed on the surface of the copper foil at this time is mechanically fragile and can be easily wiped off particularly when it is formed in the polishing liquid and wet. Therefore, even when the pressure of a polishing tool such as a polishing pad is lowered to 100 to 300 g / cm ² for grinding, a sufficient polishing rate for copper (oxine copper film) can be secured.

As described above, from the properties of the oxine copper film produced by the reaction of hydroxyquinolines with copper, hydroxyquinoline can be used to flatten the excess copper film on the insulating layer in the damascene method of semiconductor device manufacturing. The oxine copper film produced on the surface of the copper film by electrolysis is selected only by the convex parts by electrolytic polishing with a copper surface as an anode in a polishing liquid containing metals, and by polishing with a polishing tool such as a rotating polishing pad. Are ground away and the recesses are protected. Then, it is found that by continuing the operation by applying an effective current, it is possible to efficiently carry out polishing for flattening the copper film and to manufacture a product with less damage to the copper wiring layer.

[Configuration of Polishing Device Used for Polishing Using Polishing Liquid] A polishing device used for polishing using the above-described polishing liquid will be described below. FIG. 4 shows a polishing apparatus 10a according to the first embodiment of the present invention. This polishing device 10a
Has a bottomed cylindrical polishing tank 14 which opens upward and holds the polishing liquid 12 therein, and a substrate holding portion 16a which is arranged above the polishing tank 14 and holds the substrate W detachably downward. is doing.

The polishing tank 14 is directly connected to a main shaft 18 which rotates with the driving of a motor or the like, and has a bottom portion made of, for example, SUS,
A flat cathode plate 20 made of a metal such as Pt / Ti, Ir / Ti, Ti, Ta, Nb which is stable to a polishing liquid and does not become immobilized by electrolysis, and which becomes a cathode by being immersed in the polishing liquid 12 is formed. It is arranged horizontally. This cathode plate 20
Lattice-shaped long grooves 20a extending linearly over the entire length in the plane in the vertical and horizontal directions are provided on the upper surface of the. Furthermore,
On the upper surface of the cathode plate 20, for example, a continuous foam type non-woven type hardness polishing pad (for example: Rodel Nitta Co., Ltd.
A polishing tool 22 made of SUBA 800) is attached.

As a result, the polishing tank 14 rotates integrally with the polishing tool 22 as the main shaft 18 rotates, the polishing liquid 12 flows through the long grooves 20a as the polishing liquid 12 is supplied, and the electrolytic polishing also occurs. The products generated by this, hydrogen gas, oxygen gas, etc. are also discharged to the outside from between the substrate W and the polishing tool 22 through the long groove 20a.

In this example, the polishing tank 14 is rotated, but it may be scrolled (translated and rotated) or reciprocated. Further, the shape of the long groove 20a prevents a difference in current density between the central portion and the outer peripheral portion of the cathode plate 20 and allows the polishing liquid, hydrogen gas, and the like to smoothly flow along the long groove 20a. Therefore, when the polishing tank 14 makes a scroll motion, it is preferably in the form of a lattice, and when the polishing tank 14 makes a reciprocating motion, it is preferably parallel along this moving direction.

The substrate holder 16a is connected to the lower end of a support rod 24 having a rotating mechanism whose rotation speed is controllable and an up-and-down moving mechanism whose polishing pressure can be adjusted. Is adsorbed and held. The substrate holding portion 1 is provided on the outer peripheral portion of the lower surface of the substrate holding portion 16a.
When the substrate W is adsorbed and held by 6a, the copper film 6 (see FIG. 10 (a)) deposited on the surface of the substrate W is brought into contact with the peripheral portion or the bevel portion of the substrate W to make an electrical contact. Two
6 is provided. The electrical contact 26 is a roll sliding connector and wiring 28a built in the support rod 24.
Is connected to the anode terminal of the rectifier 30 as a direct current and pulse current power source arranged externally by means of the cathode plate 20.
Is connected to the cathode terminal of the rectifier 30 via the wiring 28b.

The rectifier 30 has a low voltage specification, for example,
An 8-inch wafer has a capacity of about 15V × 20A, and a 12-inch wafer has a capacity of about 15V × 30A. The frequency of the pulse current is usually ~ m
Items up to sec. are used. Further, a polishing liquid supply unit 32 for supplying the polishing liquid 12 is arranged above the polishing tank 14, and a control unit 34 and a safety device (not shown) for adjusting and managing each device and overall operation are further arranged. Are provided.

This polishing apparatus 10a is suitable for polishing the copper film 6 when the excess copper film 6 deposited on the surface of the substrate W is uniformly continuous, as shown in FIG. 10 (a). The polishing operation will be described.

The polishing liquid 12 is supplied into the polishing tank 14, and while the polishing liquid 12 overflows the polishing tank 14, the polishing tank 14 and the polishing tool 22 are integrally rotated at a rotation speed of, for example, about 90 rpm. On the other hand, the substrate W, which has been subjected to a plating treatment such as copper plating, is attracted and held downward by the substrate holding portion 76. In this state, the substrate W is lowered in the direction opposite to the polishing bath 14 while rotating at a rotation speed of, for example, about 90 rpm, and the surface (lower surface) of the substrate W is kept at a constant value of, for example, about 300 g / cm ² . The pressure is brought into contact with the surface of the polishing tool 22, and at the same time, a direct current is applied between the cathode plate 20 and the electrical contact 26 by the rectifier 30, or, for example, the current density per surface area of copper on the substrate is about 1 to 4 A / dm ^2. so,
For example, energize for 10 × 10 ⁻³ seconds and similarly 10 × 10
^-Pass a pulse current that stops for ³ seconds.

Then, the copper film is polished at a higher speed than in the conventional technique and while being effectively planarized. That is, as described above, when the polishing liquid 12 containing a hydroxyquinoline is used and electrolytic polishing is performed using copper as an anode, copper reacts with the hydroxyquinoline as shown in FIG. 5A. An insoluble oxine copper film 6a is formed on the surface of the copper film 6. The oxine copper film 6a is mechanically extremely fragile and can be easily ground and removed by a rotating low-pressure polishing tool. Therefore, when polishing with the polishing tool 22, as shown in FIG. 5B, the oxine copper film 6a generated on the surface of the convex portion of the copper film 6 is mainly ground and removed, and the copper is removed at this ground and removed portion. The film 6 is exposed to the outside. Then, the oxine copper film 6a has a relatively high electric resistance, and the energization to the part covered with the oxine copper film 6a is suppressed, and the current concentrates on the part 6b where the metal surface is exposed. Therefore, as shown in FIG. 5 (c),
The oxine copper film 6a is immediately formed on the surface where the copper film 6 is exposed by being polished first, and the oxine copper film 6a formed after this is mainly removed by grinding in the same manner as described above. That is, the surface of the concave portion of the copper film 6 is kept covered with the oxine copper film 6a, and polishing of the copper film 6 is suppressed, whereby only the convex portion of the copper film 6 is selectively ground and removed. It is a composite electropolishing that utilizes the passivation of copper.

At this time, the long groove 2 provided on the surface of the cathode plate 20.
The polishing liquid 12 is supplied between the substrate W and the polishing tool 22 from 0a, and particles floating in the polishing liquid 12 and hydrogen gas generated by the reaction pass through the long groove 20a to the outside. It flows out smoothly. After the polishing is completed, the substrate W held by the substrate holder 16a is lifted, the rotation of the substrate W is stopped, and the substrate W after the polishing is conveyed to the next step.

FIG. 6 shows a polishing apparatus 10b according to the second embodiment of the present invention. This polishing apparatus 10b differs from the polishing apparatus 10a shown in FIG. 4 in that the bottom of the polishing tank 14 is
The point is that an electrode plate 44 made of an insulating material, in which a large number of cathode rods 140 and anode rods 42 are alternately arranged inside, is horizontally arranged. Here, on the upper surface of the electrode plate 44, lattice-shaped long grooves 44a extending linearly in the vertical and horizontal directions over the entire length in the surface are provided. And the cathode rod 1
40 has a long groove 44a on the upper surface thereof along the long groove 44a.
The anode rod 42 is disposed so as to be substantially flush with the bottom surface of the a, and the anode rod 42 has an upper surface along the long groove 44a.
The porous filler 1 is arranged so as to be located, for example, 10 to 30 mm below the bottom surface of a, and above which the minute gas and polishing liquid generated can flow.
45 is filled.

All the anode rods 42 are connected to the wiring 4
6a is connected to the anode terminal of the rectifier 148 serving as a direct current and pulse current power source arranged externally through 6a, and all the cathode rods 140 are connected to each other to the cathode terminal of the rectifier 148 via the wiring 46b. There is. The rectifier 148 has a low voltage specification and a capacity of about 100V × 10A. The frequency of the pulse current is
For example, those up to msec. Are usually used.

As a result, when a metal (copper) is placed close to the electrode plate 44 and a voltage is applied from the rectifier 148 between the cathode rod 140 and the anode rod 42 of this electrode plate 44, a bipolar phenomenon at this time occurs. As a result, a positive polarity is locally generated at a position close to the cathode rod 140 on the surface of metal (copper). Further, in this example, a polishing liquid regenerating unit 50 for recovering the polishing liquid 12 overflowing the polishing tank 14 and recovering it after filtering is provided. Moreover, as the substrate holding portion 16b, one having no electrical contact is used.

In this polishing apparatus 10b, as shown in FIG. 10 (b), polishing of the excess copper film 6 deposited on the surface of the substrate W progresses, the barrier layer 5 is exposed on the surface, and the copper film 6 becomes an island. It is suitable for polishing the barrier layer 5 and the copper film 6 on the surface of the substrate when they are formed into a shape. In other words, if the copper film 6 has an island shape in this way, it is not possible to uniformly energize the copper film 6 from an external terminal such as an electrical contact. Even in such a case, according to the polishing apparatus 10b of the present embodiment, a bipolar phenomenon is used to locally form the positive polarity on the copper surface, thereby forming an oxine copper film on the copper surface. You can The polishing operation of the polishing apparatus 10b is performed by the electrode plate 4 during electrolytic polishing.
4 is the same as the case of the above-described polishing apparatus 10a except that a voltage of, for example, 50 V is applied between the cathode rod 140 and the anode rod 42.

According to this polishing apparatus 10b, the barrier layer 5
Even when the copper film 6 and the copper film 6 are exposed on the surface, excessive polishing of the copper film 6 is suppressed, the polishing rate of the remaining barrier layer 5 is increased, and both are polished flat at the same rate. In addition, it is possible to prevent the copper film 6 serving as the wiring from being damaged. That is, as described above, when the polishing liquid 12 containing a hydroxyquinoline is used and copper is made positive by the bipolar phenomenon to perform electrolytic polishing, as shown in FIG.
Copper reacts with hydroxyquinolines to form an insoluble oxine copper film 6a on the surface of the copper film 6. The oxine copper coating 6a does not dissolve in the electrolytic solution, so that the copper film 6 covered with the oxine copper coating 6a is not subjected to chemical etching. Therefore, only the surface of the barrier layer 5 is electrolytically polished, and the electrolytic polishing of the barrier layer 5 results in
As shown in (b), the copper film 6 projects upward from the plane formed by the barrier layer 5. Then, as described above, the oxine copper film 6a which is mechanically extremely fragile and can be easily ground and removed by a rotating low-pressure polishing tool is formed on the surface of the copper film 6 protruding upward as described above. Therefore, this oxine copper coating 6a is ground and removed to be flat. Moreover, since the copper film 6 (oxine copper film 6a) is ground and removed by the rotating low-pressure polishing tool 22, it is possible to prevent the surface of the copper film 6 from being damaged. The barrier layer 5
Before the exposure, only the convex portions of the copper film 6 are selectively ground and removed as in the case of the polishing apparatus 10a described above. The compositions of the first polishing treatment liquid and the second polishing treatment liquid may be different. In the second polishing step, the copper film and the barrier film having different conductivity must be polished at the same rate at the same time, so the copper film becomes a passivation film, but the barrier film requires a polishing solution with many chemical polishing elements. Become.

FIG. 8 shows the polishing apparatus 10a shown in FIG. 4 and FIG.
3 is a plan layout view of a wiring forming apparatus including the polishing apparatus 10b shown in FIG. This wiring forming device is located inside the housing 52, and a load / unload unit 54, and a copper plating device 156, a cleaning device 158, and an annealing device 16 which are sequentially arranged from the opposite side of the load / unload unit 54.
0, the polishing apparatus (first polishing apparatus) 10a shown in FIG. 4, and FIG.
A polishing apparatus (second polishing apparatus) 10b and a cleaning / drying apparatus 162 shown in FIG. 2 are provided, and a transporting apparatus 68 that can travel along the transporting path 66 and transfers the substrate between them is provided.

Next, the wiring forming process will be described with reference to FIGS. 9 and 10. The substrate W having the seed layer 7 formed on the surface (see FIG. 18A) is loaded / unloaded by the loading / unloading unit 54.
From the transfer device 68 one by one, and the copper plating device 1
Bring to 56. And this copper plating device 156
Then, for example, electrolytic copper plating is performed to form a copper film 6 on the surface of the substrate W as shown in FIG. next,
The substrate W after the copper plating treatment is transferred to the cleaning device 158 for cleaning, and then transferred to the annealing device 160.
Then, the substrate W on which the copper film 6 is deposited is subjected to heat treatment to anneal the copper film 6, and is transported to the first polishing apparatus 10a.

Then, with this first polishing apparatus 10a, the surface of the substrate W (the surface to be plated) is subjected to a first polishing treatment, whereby the copper film 6 deposited on the upper surface of the barrier layer 5 is polished, The first polishing is completed when the thickness of the copper film 6 of the barrier layer 5 reaches a predetermined value. Thus, the first polishing device 10a
By performing the first polishing with, the polishing rate can be increased. Then, the substrate W is transported to the second polishing apparatus 10b and the surface of the substrate W is subjected to the second polishing process. At this time, as shown in FIG. 10B, when the barrier layer 5 is exposed, the barrier layer 5 on the insulating layer 2 and the surface of the copper film 6 are polished at the same time. As shown in, the surface of the insulating layer 2 and the surface of the wiring made of the copper film 6 are made flush with each other. That is, in the second polishing apparatus 10b, the bipolar phenomenon is utilized in accordance with the conventional chemical mechanical polishing (CMP), and the copper surface is locally made to have a positive polarity, so that the oxine is not formed on the copper surface. A copper film can be formed, and therefore, even if the barrier layer 5 is exposed and the copper film 6 is separated into islands, the polishing process can be continued. Then, the substrate after the polishing process is washed and dried by the apparatus 1
The substrate is transported to 62, where the substrate is washed and dried, and then the transport device 68 returns it to the original cassette of the loading / unloading unit 54.

11 and 12 show a polishing apparatus 10c according to still another embodiment of the present invention. This polishing device 10c
6 and the polishing apparatus (first polishing apparatus) 10a shown in FIG.
The second polishing apparatus (second polishing apparatus) 10b shown in FIG. 1 is placed in a partitioned room in the same module 70, and the first polishing apparatus 10a for the substrate W is moved by the turning arm 72 placed inside this room. And the second polishing device 10b. That is, as shown in FIG. 12, the polishing apparatus 10c includes a detachable electrode ring 74, a substrate holding portion 76 connected to the free end of the swivel arm 72, and a substrate on which the electrode ring 74 is mounted. The holder 76 constitutes the substrate holder 16a of the first polishing apparatus 10a, and the substrate holder 76 without the electrode ring 74 constitutes the substrate holder 16b of the second polishing apparatus 10b. An electrode ring attaching / detaching stage 78 for attaching / detaching the electrode ring 74 is arranged inside the module 70.

According to this example, with the electrode ring 74 attached, the substrate is held outside the module 70 by the substrate holder 7.
6 is sucked and held and carried into the module 70, and the substrate holding portion 76 having the electrode ring 74 mounted thereon constitutes the first polishing apparatus 10a to perform the same first polishing process as described above. After the completion of the first polishing process, the substrate holding part 76 is attached to the electrode ring attaching / detaching stage 78 while holding the substrate W.
The electrode ring 74 is removed here, and the substrate holder 76 with the electrode ring 74 removed is used to remove the second polishing apparatus 10b.
Then, the second polishing process similar to the above is performed. Then, the substrate after the second polishing process is carried to the outside of the module 70 while being held by the substrate holding part 76.

In this polishing apparatus 10c, as shown in FIG. 13, by disposing the polishing apparatus 10c at the positions where the first polishing apparatus 10a and the second polishing apparatus 10b shown in FIG. 8 are arranged, continuous wiring is achieved. A forming process can be performed.

14 to 16 show a polishing apparatus 10d according to still another embodiment of the present invention. This polishing device 10d
The above-described first polishing process and second polishing process can be performed in the same polishing tank. The difference from the polishing device 10b shown in FIG. 6 is that the polishing device 10a shown in FIG. Substrate holding portion 16a and rectifier (first rectifier) 3
0, the wiring 28a extending from the anode of the first rectifier 30 is connected to the electrical contact 26 of the substrate holding portion 16a, and the wiring 28b extending from the cathode is connected to the rectifier (second rectifier) 148.
The rectifiers 30 and 148 can be switched by connecting to the wiring 46a extending from the cathode.

Further, in this example, the polishing tank 14 is configured to perform a scrolling motion, and the polishing liquid flow passage 51 (FIG. 15) which vertically communicates with the inside of the polishing tank 14 and the electrode plate 44. Is provided, and the polishing liquid 12 is supplied into the polishing tank 14 through the polishing liquid flow passage 51.

Further, on the upper surface of the electrode plate 44, for example, the depth H
₁ is provided with a long groove 44a of about 3 mm.
The bottom surface of a and the top surface of the anode rod 42 are flush with each other, and the cathode rod 140 is arranged at the center of each portion that is partitioned by the long groove 44a and projects in a rectangular shape. ₂ is provided with a recess 44b of 1 mm, and the recess 44b and the long groove 44a communicate with each other via a communication groove 44c extending in a cross shape.
As a result, the polishing liquid 12 supplied from the polishing liquid flow passage 51 into the polishing tank 14 flows along the long groove 44a and further reaches the inside of the recess 44b from the communication groove 44c, whereby the cathode rod 140 and the anode rod The upper surface of 42 contacts the polishing liquid 12.

According to this example, a voltage is applied between the electrical contact 26 and the cathode rod 140 from the first rectifier 30,
The second polishing process can be performed by performing the first polishing process described above, switching the rectifier, and applying a voltage from the second rectifier 148 between the cathode rod 140 and the anode rod 42.

19 to 27 show an electroplating device which constitutes the copper plating device 156 provided in FIG. As shown in FIG. 19, this electroplating apparatus has a plating treatment tank 46 having a substantially cylindrical shape and containing a plating solution 45 therein.
And a head portion 47 that is arranged above the plating treatment tank 46 and holds the substrate W. Note that FIG. 6 shows a state in which the head portion 47 holds the substrate W and the liquid level of the plating solution 45 is raised to a plating position.

The plating bath 46 has a plating chamber 49 which is open upward and has an anode 48 at the bottom, and a plating bath 50 which holds a plating solution 45 in the plating chamber 49 is provided. .. On the inner peripheral wall of the plating tank 50, plating solution jet nozzles 53 that horizontally project toward the center of the plating chamber 49 are arranged at equal intervals along the circumferential direction. The inside of 50 is communicated with a plating solution supply passage extending vertically.

Further, in this example, a punch plate 220 having a large number of holes of, for example, about 3 mm is arranged above the anode 48 in the plating chamber 49, whereby the black formed on the surface of the anode 48 is arranged. The film is prevented from being rolled up by the plating solution 45 and flowing out.

In the plating tank 50, the first plating solution outlet 57 for drawing out the plating solution 45 in the plating chamber 49 from the peripheral edge of the bottom of the plating chamber 49, and a dam member provided at the upper end of the plating tank 50. A second plating solution discharge port 59 for discharging the plating solution 45 overflowing 58 and a third plating solution discharge port 120 for discharging the plating solution 45 before overflowing the dam member 58 are provided, and the dam member 58 is further provided. As shown in FIG. 25, the lower portion of the opening 2 has openings 2 of a predetermined width at predetermined intervals.
22 is provided.

As a result, when the amount of plating to be supplied is large during the plating process, the plating solution is discharged from the third plating solution discharge port 120 to the outside, and the dam member 58 is provided as shown in FIG. 25 (a). Overflow and then open 2
It is also discharged through the second plating solution discharge port 59 after passing through 22. Further, when the plating amount is small during the plating process, the plating solution is discharged to the third plating solution outlet 120.
25 (b), it is also discharged from the second plating solution discharge port 59 to the outside as shown in FIG. 25 (b), whereby the amount of plating can be easily dealt with. It has become.

Further, as shown in FIG. 25D, a through hole 224 for controlling the liquid level which is located above the plating solution jet nozzle 53 and connects the plating chamber 49 and the second plating solution discharge port 59. Are provided at a predetermined pitch along the circumferential direction, which allows the plating solution to pass through the through-holes 224 during non-plating and to be discharged to the outside from the second plating solution discharge port 59. It is designed to be controlled. The through hole 224 plays a role of an orifice during the plating process and limits the amount of the plating solution flowing out from the orifice.

As shown in FIG. 20, the first plating solution discharge port 57 has a reservoir 226 through the plating solution discharge pipe 60a.
A flow rate adjuster 61a is interposed in the middle of the plating solution discharge pipe 60a. Second plating solution outlet 59
The third plating solution discharge port 120 and the third plating solution discharge port 120 are directly connected to the reservoir 226 via the plating solution discharge pipe 60b after they join each other inside the plating tank 50.

The plating solution 45 contained in the reservoir 226
Enters the plating solution adjusting tank 40 from the reservoir 226 by the pump 228. The plating solution adjusting tank 40 is provided with a temperature controller 230 and a plating solution analyzing unit 232 for taking out and analyzing the sample solution, and the filter from the plating solution adjusting tank 40 is driven by a single pump 234 being driven. 236 through the plating solution 45
Are supplied to the plating solution jet nozzle 53 of the copper plating apparatus 156. This plating solution adjustment tank 40
A control valve 56 for keeping the pressure on the secondary side constant is provided in the middle of the plating solution supply pipe 55 extending from the copper plating apparatus 156 to the copper plating apparatus 156.

Returning to FIG. 19, the central portion of the plating solution surface is pushed upward by the upper and lower split flows of the plating solution 45 located in the vicinity of the inside of the plating chamber 49. A vertical rectifying ring 62 and a horizontal rectifying ring 63, which are arranged to raise and smooth the downward flow and to make the current density distribution more uniform, are arranged by fixing the outer peripheral end of the horizontal rectifying ring 63 to the plating tank 50. Has been done.

On the other hand, the head portion 47 is provided with a housing 70 having a bottomed cylindrical shape which is rotatably open downward and has an opening 94 in the peripheral wall, and a vertically movable push rod 242 having a press ring 240 attached to the lower end. Has been. As shown in FIG. 10, FIG. 23, and FIG. 24, a ring-shaped substrate holding portion 72 that projects inward is provided at the lower end of the housing 70. A ring-shaped sealing material 244 having a tip protruding upward in a spire shape.
Is installed. Further, the cathode electrode contact 76 is arranged above the sealing material 244. In addition, the substrate holding portion 72 is provided with air vent holes 75 that extend outward in the horizontal direction and further incline upward toward the outside at equal intervals along the circumferential direction.

As a result, as shown in FIG. 19, with the liquid level of the plating solution 45 lowered, the substrate W is held by the suction hand H or the like as shown in FIGS. The sealing material 244 of the substrate holder 72.
After the suction hand H is pulled out from the housing 70, the pressing ring 240 is lowered. As a result, the peripheral edge portion of the substrate W is sealed with the sealing material 244 and the pressing ring 24.
The lower surface of 0 holds the substrate W by sandwiching it, and when the substrate W is held, the lower surface of the substrate W and the sealing material 244 are in pressure contact,
This is surely sealed, and at the same time, the substrate W and the cathode electrode contact 76 are energized.

Returning to FIG. 19, the housing 70 is connected to the output shaft 248 of the motor 246 and is configured to rotate by the drive of the motor 246. The pressing rod 242 also supports the support 25 surrounding the motor 246.
A ring-shaped support frame 258 rotatably supported by a lower end of a slider 254 that moves up and down by the operation of a cylinder 252 with a guide fixed to 0 at a predetermined position along the circumferential direction. The cylinder 252 is moved up and down by the operation of the cylinder 252, and is rotated integrally with the housing 70 when the substrate W is held.

The support 250 is attached to a slide base 262 that moves up and down by screwing with a ball screw 261 that rotates as the motor 260 is driven, and is surrounded by an upper housing 264 to drive the motor 260. And moves up and down together with the upper housing 264. Further, a lower housing 257 that surrounds the periphery of the housing 70 during the plating process is attached to the upper surface of the plating tank 50.

As a result, as shown in FIG. 22, maintenance can be performed with the support 250 and the upper housing 264 being raised. Further, although crystals of the plating solution are likely to adhere to the inner peripheral surface of the dam member 58, a large amount of plating solution is caused to flow over the dam member 58 while the support 250 and the upper housing 264 are raised. By overflowing, it is possible to prevent the plating solution crystals from adhering to the inner peripheral surface of the dam member 58. Further, the plating tank 50 is integrally provided with a plating solution splash prevention cover 50b that covers the upper portion of the plating solution that overflows during the plating process. By coating a super water-repellent material (made by Technology Co., Ltd.) or the like, it is possible to prevent the plating solution crystals from adhering thereto.

A substrate centering mechanism 270 for centering the substrate W is located above the substrate holding portion 72 of the housing 70.
However, in this example, they are provided at four locations along the circumferential direction. FIG. 26 shows the details of the substrate centering mechanism 270, which has a gate-shaped bracket 272 fixed to the housing 70 and a positioning block 274 arranged in the bracket 272. The upper part of the 274 is swingably supported by a pivot 276 horizontally fixed to the bracket 272, and a compression coil spring 278 is interposed between the housing 70 and the positioning block 274. As a result, the positioning block 274 causes the compression coil spring 27 to move.
The lower part is urged inwardly about the pivot 276 via 8 and its upper surface 274a functions as a stopper and abuts against the upper lower surface 272a of the bracket 272, whereby the positioning block 274 moves. It is becoming regulated. Furthermore, the inner surface of the positioning block 274 is a tapered surface 274b that expands outward in the upward direction.

As a result, when the substrate is held by a suction hand such as a transfer robot and transferred into the housing 70 and placed on the substrate holder 72, the center of the substrate deviates from the center of the substrate holder 72. Then, the positioning block 274 pivots outward against the elastic force of the compression coil spring 278, and the gripping by a suction hand such as a transfer robot is released.
The positioning block 27 is generated by the elastic force of the compression coil spring 278.
By returning 4 to the original position, the substrate can be centered.

FIG. 27 shows a power supply contact (probe) 77 for supplying power to the cathode electrode plate 208 of the cathode electrode contact 76.
This power supply contact 77 is composed of a plunger, is surrounded by a cylindrical protective body 280 reaching the cathode electrode plate 208, and is protected from the plating solution.

Next, the plating process by the copper plating apparatus (electroplating apparatus) 156 will be described. First,
When the substrate is transferred to the copper plating apparatus 156, the suction hand of the transfer robot 68 shown in FIG. 8 and the substrate W suction-held with its surface facing downward are held in the opening 9 of the housing 70.
4, the suction hand is moved downward, the vacuum suction is released, the substrate W is placed on the substrate holding portion 72 of the housing 70, and then the suction hand is raised. Pull out from the housing 70. Next, the pressing ring 240 is lowered to move the peripheral portion of the substrate W to the substrate holding portion 72.
The substrate W is held by being sandwiched by the lower surface of the pressing ring 240.

Then, the plating solution jetting nozzle 53 jets the plating solution 45, and at the same time, the housing 70 and the substrate W held therein are rotated at a medium speed, and the plating solution 45 is filled up to a predetermined amount, and several seconds have passed. When the housing 70 is rotated, the rotation speed of the housing 70 is rotated at a low speed (for example, 100 mi.
n ⁻¹ ), the anode 48 is used as the anode, and the substrate-treated surface is used as the cathode, and a plating current is passed to perform electrolytic plating.

After the energization is completed, as shown in FIG. 25 (d), the plating solution is made to flow out only from the through hole 224 for controlling the liquid level located above the plating solution jet nozzle 53. Is reduced to expose the housing 70 and the substrate held thereby to the plating solution surface. At a position where the housing 70 and the substrate W held by the housing 70 are above the liquid surface, high speed (for example, 500
Rotate at ~ 800 min ^-1 ) to drain the plating solution by centrifugal force. After draining is completed, the housing 70
The rotation of the housing 70 is stopped so as to face in a predetermined direction.

After the housing 70 is completely stopped, the pressing ring 240 is raised. Next, the transfer robot 28b
The suction hand is inserted into the housing 70 from the opening 94 with the suction surface facing downward, and the suction hand is lowered to a position where the suction hand can suction the substrate. And
The substrate is vacuum-sucked by a suction hand, and the suction hand is moved to a position above the opening 94 of the housing 70.
The suction hand and the substrate held therein are taken out from the opening 94 of the housing 70.

According to this copper plating device 156, the mechanical simplification and compactness of the head portion 47 are achieved, and the plating treatment is performed when the liquid level of the plating solution in the plating tank 46 is at the liquid level during plating. When the substrate is delivered, the substrate can be drained and delivered when it is on the liquid surface, and further, the black film formed on the surface of the anode 48 can be prevented from being dried or oxidized.

28 to 33 show a copper plating apparatus 156.
2 shows another electroplating apparatus constituting the above. As shown in FIG. 28, this copper plating apparatus is provided with a substrate processing unit 2-1 that performs a plating process and its incidental processes, and a plating solution that stores a plating solution adjacent to the substrate processing unit 2-1. The tray 2-2 is arranged. Further, the substrate processing unit 2 is held at the tip of the arm 2-4 that swings around the rotation shaft 2-3.
-1 and the electrode part 2 that swings between the plating solution tray 2-2
An electrode arm portion 2-6 having -5 is provided.

Furthermore, the precoat / recovery arm 2-7 is located on the side of the substrate processing section 2-1 and a fixed nozzle for injecting a chemical liquid such as pure water or ion water, or a gas toward the substrate. 2-8 are arranged. Here, three fixed nozzles 2-8 are arranged, and one of them is used for supplying pure water. As shown in FIGS. 29 and 30, the substrate processing unit 2-1 includes a substrate holding unit 2-9 which holds the substrate W with the plating surface facing upward, and the substrate holding unit 2-9 above the substrate holding unit 2-9. The cathode portion 2-10 is provided so as to surround the peripheral portion of the portion 2-9. Further, an air cylinder 2-12 is provided with a cup 2-11 which has a substantially cylindrical shape with a bottom and which surrounds the substrate holding portion 2-9 and prevents scattering of various chemicals used during processing.
It is arranged so that it can move up and down through.

Here, the substrate holder 2-9 uses the air cylinder 2-12 to move between the lower substrate transfer position A, the upper plating position B, and the intermediate pretreatment / cleaning position C between them. It is designed to go up and down. The substrate holding unit 2-9 is configured to rotate integrally with the cathode unit 2-10 at an arbitrary acceleration and speed via the rotation motor 2-14 and the belt 2-15. A substrate carry-in / out port (not shown) is provided on the side of the frame of the electrolytic copper plating apparatus on the side of the transfer robot (not shown) facing the substrate transfer position A, and the substrate holding portion 2-9 is located at the plating position. B
The seal member 2-16 of the cathode portion 2-10 and the cathode electrode 2-17, which will be described below, come into contact with the peripheral edge of the substrate W held by the substrate holding portion 2-9. On the other hand, the upper end of the cup 2-11 is located below the substrate carry-in / out port, and reaches the upper part of the cathode portion 2-10 when rising, as shown by the phantom line in FIG.

When the substrate holder 2-9 moves up to the plating position B, the cathode electrode 2-17 is pressed against the peripheral edge of the substrate W held by the substrate holder 2-9 and the substrate W is energized. At the same time, the inner peripheral end of the seal member 2-16 is pressed against the upper surface of the peripheral edge of the substrate W to seal it water-tightly, so that the plating solution supplied to the upper surface of the substrate W stains from the end of the substrate W. This prevents the plating solution from being contaminated and also prevents the plating solution from contaminating the cathode electrode 2-17.

The electrode portion 2-5 of the electrode arm portion 2-6 surrounds the housing 2-18 and the periphery of the housing 2-18 at the free end of the swing arm 2-4, as shown in FIG. A hollow support frame 2-19, and an anode 2-2 in which the peripheral portion is sandwiched and fixed by the housing 2-18 and the support frame 2-19.
It has 0 and. The anode 2-20 is the housing 2
A suction chamber 2-21 is formed inside the housing 2-18 so as to cover the opening of -18. As shown in FIGS. 32 and 33, the suction chamber 2-21 is connected to a plating solution introduction pipe 2-28 for introducing and discharging the plating solution and a plating solution discharge pipe (not shown). Further, the anode 2-20 is provided with a large number of through holes 2-20b which are vertically communicated with each other over the entire surface thereof.

In this embodiment, the anode 2-
A plating solution impregnated material 2-22 made of a water-retaining material is attached to the lower surface of the anode 2-20 so as to cover the entire surface of the anode 2-20.
By moistening the surface of -20, the black film is prevented from dropping onto the plating surface of the substrate, and at the same time, when the plating solution is injected between the plating surface of the substrate and the anode 2-20, air is exposed to the outside. It is easy to pull out. The plating solution impregnated material 2-22 is, for example, a woven fabric, a non-woven fabric or a sponge-like structure made of at least one material selected from the group consisting of polyethylene, polypropylene, polyester, polyvinyl chloride, Teflon, polyvinyl alcohol, polyurethane and derivatives thereof, or It consists of porous ceramics.

Anode 2-2 of plating solution impregnated material 2-22
The attachment to 0 is performed as follows. That is, a large number of fixing pins 2-25 each having a head at the lower end are housed in the plating solution impregnated material 2-22 so as not to escape upward, and the shaft portion penetrates the inside of the anode 2-20. The fixing pin 2-25 is urged upward through the U-shaped leaf spring 2-26, so that the plating solution impregnated material 2-22 is placed on the lower surface of the anode 2-20. It is attached in close contact with the elastic force of 26. With this configuration, the plating solution impregnated material 2-22 can be securely adhered to the lower surface of the anode 2-20 even if the thickness of the anode 2-20 gradually decreases as the plating progresses. You can
Therefore, it is possible to prevent air from being mixed between the lower surface of the anode 2-20 and the plating solution impregnated material 2-22 to cause a plating failure.

A columnar PVC (polyvinyl chloride) or PET (polyethylene terephthalate) pin having a diameter of, for example, about 2 mm was placed through the anode from the upper surface side of the anode, and the pin appeared on the lower surface of the anode. An adhesive may be attached to the tip end surface of the pin so as to be adhesively fixed to the plating solution impregnated material. The anode and the plating solution impregnated material can be used in contact with each other, but it is also possible to form a gap between the anode and the plating solution impregnated material and perform the plating treatment while the plating solution is held in this gap. This gap is selected from the range of 20 mm or less, but preferably 0.1
It is selected from the range of -10 mm, more preferably 1-7 mm. In particular, when a soluble anode is used, the anode is dissolved from the bottom, so that the gap between the anode and the plating solution impregnated material increases with time, and is 0 to 20 m.
There is a gap of about m.

Then, the electrode portion 2-5 has the substrate W held by the substrate holding portion 2-9 and the plating solution impregnated material 2 when the substrate holding portion 2-9 is at the plating position B (see FIG. 30). −
It is lowered until the gap with 22 is about 0.1 to 10 mm, preferably 0.3 to 3 mm, and more preferably about 0.5 to 1 mm. In this state, the plating solution is supplied from the plating solution supply pipe. While the plating solution impregnating material 2-22 contains the plating solution, the plating solution is filled between the upper surface (the surface to be plated) of the substrate W and the anode 2-20 to form the upper surface (the surface to be plated) of the substrate W. The surface to be plated of the substrate W is plated by applying a voltage from the plating power supply to the anode 2-20.

Next, the plating process by the copper plating apparatus (electroplating apparatus) 156 will be described. First,
The substrate W before plating is carried into the substrate holder 2-9 at the substrate transfer position A by the transfer robot 68 (see FIG. 8) and placed on the substrate holder 2-9. Next cup 2-1
1 is raised, and at the same time, the substrate holder 2-9 is raised to the pretreatment / cleaning position C. In this state, the precoat / recovery arm 2-7, which was in the retracted position, is moved to a position facing the substrate W, and the precoat nozzle provided at the tip of the precoat / recovery arm 2-7 applies a precoat liquid such as a surfactant to the surface of the substrate W to be plated. Discharge intermittently. At this time, since the substrate holder 2-9 is rotating, the precoat liquid is spread over the entire surface of the substrate W.
Next, the precoat / recovery arm 2-7 is returned to the retracted position, the rotation speed of the substrate holder 2-9 is increased, and the precoat liquid on the surface to be plated of the substrate W is shaken off and dried by the centrifugal force.

Then, the electrode arm portion 2-6 is swung in the horizontal direction so that the electrode portion 2-5 is located above the plating solution tray 2-2 and above the plating position, and the electrode 2-5 is placed at this position. Are lowered toward the cathode portion 2-10. When the lowering of the electrode portion 2-5 is completed, the anode 2-20
A plating voltage is applied to the cathode part 2-10 and the plating solution is supplied to the inside of the electrode part 2-5, and the plating solution is impregnated into the plating solution impregnated material 2-22 from the plating solution supply port penetrating the anode 2-20. To supply. At this time, the plating solution impregnated material 2-22
Does not come into contact with the surface to be plated of the substrate W and is about 0.1 to 10 mm, preferably 0.3 to 3 mm, more preferably 0.5.
It is in a state of approaching about 1 mm.

When the supply of the plating solution is continued, the plating solution containing Cu ions exuded from the plating solution impregnated material 2-22 forms a gap between the plating solution impregnated material 2-22 and the surface of the substrate W to be plated. And the surface of the substrate W to be plated is Cu-plated. At this time, the substrate holder 2-9 may be rotated at a low speed.

When the plating process is completed, the electrode arm portion 2
After raising -6, it is swung to return the electrode portion 2-5 to the upper position of the plating solution tray 2-2 and lower it to the normal position.
Next, the precoat / recovery arm 2-7 is moved from the retracted position to a position facing the substrate W and lowered, and the rest of the plating solution on the substrate W is recovered from a plating solution recovery nozzle (not shown). After the recovery of the rest of the plating solution is completed, the precoat / recovery arm 2-7 is returned to the retracted position, and the substrate W
Pure water is discharged to the center of the substrate, and at the same time, the substrate holder 2-9 is rotated at an increased speed to replace the plating solution on the surface of the substrate W with pure water.

After the rinsing is completed, the substrate holder 2-9 is lowered from the plating position B to the pretreatment / cleaning position C, and pure water is supplied from the fixed nozzle 2-8 for pure water while the substrate holder 2 is supplied.
-9 and the cathode part 2-10 are rotated to perform water washing. At this time, pure water directly supplied to the cathode section 2-10,
Alternatively, the seal member 2 may be made of pure water scattered from the surface of the substrate W.
-16 and the cathode electrode 2-17 can be cleaned simultaneously with the substrate W.

After the washing with water is completed, the supply of pure water from the fixed nozzle 2-8 is stopped, the rotation speeds of the substrate holding portion 2-9 and the cathode portion 2-10 are further increased, and the surface of the substrate W is centrifuged by the centrifugal force. Shake off pure water and dry. At the same time, the seal member 2-16 and the cathode electrode 2-17 are also dried. When the drying is completed, the rotation of the substrate holding unit 2-9 and the cathode unit 2-10 is stopped, and the substrate holding unit 2-9 is lowered to the substrate delivery position A.

FIG. 34 is a plan layout view of a substrate processing apparatus equipped with the above-described plating apparatus. As shown in the figure, this substrate processing apparatus performs a loading / unloading area 520 for delivering and receiving a substrate cassette accommodating semiconductor substrates, a process area 530 for performing process processing, and cleaning and drying of the semiconductor substrate after the process processing. A cleaning / drying area 540 is provided. The cleaning / drying area 540 is arranged between the loading / unloading area 520 and the process area 530. Loading / unloading area 520 and washing / drying area 540
A partition 521 is provided in the above, and a partition 523 is provided between the cleaning / drying area 540 and the process area 530.

The partition 521 has a loading / unloading area 520.
A passage (not shown) for transferring the semiconductor substrate is provided between the cleaning and drying area 540 and a shutter 522 for opening and closing the passage. In addition, the partition wall 523
Also, a passage (not shown) for transferring the semiconductor substrate is provided between the cleaning / drying area 540 and the process area 530, and a shutter 524 for opening and closing the passage is provided. Cleaning / drying area 540 and process area 53
0 can supply and exhaust air independently.

The substrate processing apparatus for wiring a semiconductor substrate having the above-described structure is installed in a clean room, and the pressure in each area is (pressure in the loading / unloading area 520)> (pressure in the cleaning / drying area 540)> (process area) (The pressure of 530) and the pressure of the carry-in / carry-out area 520 is set lower than the pressure in the clean room. This allows
Prevent air from flowing from the process area 530 to the cleaning / drying area 540, and prevent air from flowing from the cleaning / drying area 540 to the loading / unloading area 520,
Further, air is prevented from flowing out of the carry-in / carry-out area 520 into the clean room.

In the carry-in / carry-out area 520, there is a load unit 52 for accommodating a substrate cassette accommodating semiconductor substrates.
0a and unload unit 520b are arranged.
In the cleaning / drying area 540, two water washing sections 541 and two drying sections 542 for performing post-plating processing are arranged, and a transfer section (transfer robot) for transferring semiconductor substrates.
543 is provided. As the water washing section 541, for example, a pencil type with a sponge on the front end or a roller type with a sponge is used. Drying part 5
As 42, for example, a type in which a semiconductor substrate is spun at high speed to dehydrate and dry is used. In the process area 530, a pretreatment tank 531 for performing a pretreatment for plating a semiconductor substrate and a plating tank (plating device) 532 for performing a copper plating treatment are arranged, and a transport unit (transportation) for transporting a semiconductor substrate. Robot 533 is provided.

FIG. 35 shows the flow of airflow in the substrate processing apparatus. In the cleaning / drying area 540, piping 546
Fresher external air is taken in and high performance filter 544
Is pressed by a fan through the ceiling 540a, and the washing section 541 and the drying section 5 are provided as clean air having a downflow from the ceiling 540a.
It is supplied around 42. Most of the clean air supplied is supplied from the floor 540b to the ceiling 54 through the circulation pipe 545.
It is returned to the 0a side, pushed again by the fan through the high-performance filter 544, and circulates in the cleaning / drying area 540. Part of the airflow is the washing part 541 and the drying part 542.
The air is exhausted from the inside through the duct 552.

Although the process area 530 is called a wet zone, particles are not allowed to adhere to the surface of the semiconductor substrate. Therefore, the process area 530
Particles are prevented from adhering to the semiconductor substrate by being pushed in by a fan from the ceiling 530a and flowing down-flow clean air through the high-performance filter 533. However, if the total flow rate of the clean air that forms the downflow depends on the supply / exhaust from the outside, a huge amount of supply / exhaust is required. For this reason, only the exhaust to the extent that the pressure in the room is kept negative is the external exhaust from the duct 553, and most of the downflow air is supplied to the pipe 53.
It is designed to be covered by the circulating air flow through 4,535.

When the circulating air flow is used, the process area 5
The clean air that has passed through 30 contains the chemical liquid mist and gas, so the clean air is passed through the scrubber 536 and the mito separator 53.
Remove through 7,538. As a result, the ceiling 530a
The air that has returned to the side circulation duct 534 does not contain the chemical mist or gas, is pushed again by the fan, passes through the high-performance filter 533, and circulates in the process area 530 as clean air. A portion of the air that has passed through the process area 530 from the floor portion 530b is duct 55
The air containing the chemical liquid mist and the gas is discharged to the outside through the duct 553. Ceiling 53
From the 0a duct 539, fresh air corresponding to these exhaust amounts is supplied to the process area 530 to such an extent that the negative pressure is maintained.

As described above, the respective pressures of the carry-in / carry-out area 520, the cleaning / drying area 540 and the process area 530 are: (pressure of the carry-in / carry-out area 520)> (pressure of the cleaning / drying area 540)> (process Area 530 pressure). Therefore, the shutters 522, 524
When (see FIG. 34) is opened, the air flow between these areas, as shown in FIG.
0, cleaning / drying area 540 and process area 530
Flow in order. Further, the exhaust gas is collected in the collective exhaust duct 554 through the ducts 552 and 553, as shown in FIG.

FIG. 36 is an external view showing an example in which the substrate processing apparatus is arranged in a clean room. Cassette delivery port 555 and operation panel 55 in the loading / unloading area 520
A side face 6 is exposed to a working zone 558 having a high cleanliness of a clean room partitioned by a partition wall 557, and the other side faces are housed in a utility zone 559 having a low cleanness.

As described above, the cleaning / drying area 540 is disposed between the loading / unloading area 520 and the process area 530, and the loading / unloading area 520 and the cleaning / drying area 5 are arranged.
40 and between the cleaning / drying area 540 and the process area 530, the partition walls 521 are provided, so that the partition wall 521 is carried from the working zone 558 into the substrate processing apparatus for semiconductor substrate wiring through the cassette transfer port 555 in a dried state. The semiconductor substrate to be processed is plated in the substrate processing apparatus, and is carried out to the working zone 558 in a cleaned and dried state. Therefore, particles and mist do not adhere to the surface of the semiconductor substrate and the cleanliness in the clean room is maintained. The high working zone 558 is not contaminated with particles, chemicals or cleaning liquid mist.

In FIGS. 34 and 35, the substrate processing apparatus has a loading / unloading area 520 and a cleaning / drying area 54.
0, the example in which the process area 530 is provided is shown, but an area in which the CMP device is arranged is provided in the process area 530 or adjacent to the process area 530, and the process area 530 or the area in which the CMP device is arranged and the carry-in / carry-out. A cleaning / drying area 540 may be arranged between the areas 520. The point is that the semiconductor substrate may be carried into the substrate processing apparatus for wiring the semiconductor substrate in a dry state, and the semiconductor substrate after the plating process may be washed and discharged in a dried state.

In the above example, the substrate processing apparatus has been described by taking the plating apparatus for semiconductor substrate wiring as an example, but the substrate is not limited to the semiconductor substrate, and the portion to be plated is also formed on the substrate surface. It is not limited to the wiring part. Further, in the above example, copper plating was described as an example, but the invention is not limited to copper plating.

FIG. 38 is a diagram showing a planar structure of another substrate processing apparatus for wiring a semiconductor substrate. As shown in the figure, a substrate processing apparatus for wiring a semiconductor substrate includes a carry-in section 601 for carrying in a semiconductor substrate, a copper plating tank 602 for copper plating, washing tanks 603, 604 for water washing, and a chemical mechanical polishing (CM).
PMP part 605 for performing P), water washing tanks 606 and 607, a drying tank 608, and a carry-out section 609 for carrying out the semiconductor substrate on which the wiring layer formation has been completed. Are arranged as one device to form a substrate processing device for semiconductor substrate wiring.

In the substrate processing apparatus having the above arrangement, the substrate transfer means takes out the semiconductor substrate on which the wiring layer is not formed from the substrate cassette 601-1 placed on the carry-in section 601 and transfers it to the copper plating tank 602. To do. In the copper plating tank 602, a copper plating layer is formed on the surface of the semiconductor substrate W including a wiring portion including wiring grooves and wiring holes (contact holes).

The semiconductor substrate W on which the copper plating layer has been formed in the copper plating tank 602 is washed with the substrate transferring means 60 in a water washing tank 60.
3 and the washing tank 604, and wash with water. Subsequently, the semiconductor substrate W that has been washed with water is transferred to the CMP section 605 by a substrate transfer means, and in the CMP section 605, the copper plating layer formed in the wiring groove or the wiring hole from the copper plating layer is left and the semiconductor substrate W is left. The copper plating layer on the surface of is removed.

Subsequently, the semiconductor substrate in which the unnecessary copper plating layer on the surface of the semiconductor substrate W has been removed leaving the copper plating layer formed in the wiring portion including the wiring groove and the wiring hole from the copper plating layer as described above. W is sent to the washing tank 606 and the washing tank 607 by the substrate transfer means, washed with water, and the semiconductor substrate W after the water washing is dried in the drying tank 608, and the dried semiconductor substrate W is formed into a wiring layer. The finished semiconductor substrate is stored in the substrate cassette 609-1 of the carry-out section 609.

FIG. 39 is a diagram showing a planar structure of another substrate processing apparatus for wiring a semiconductor substrate. The substrate processing apparatus shown in FIG. 39 differs from the apparatus shown in FIG. 38 in that the copper plating bath 6
02, water washing tank 610, pretreatment tank 611, lid plating tank 612 for forming a protective film on the surface of the copper plating film, CMP section 61
5 and the washing tanks 613 and 614 were added, and it was configured as one device including these.

In the substrate processing apparatus having the above arrangement, the copper plating layer is formed on the surface of the semiconductor substrate W including the wiring portion including the wiring groove and the wiring hole (contact hole). Subsequently, the CMP portion 605 removes the copper plating layer on the surface of the semiconductor substrate W, leaving the copper plating layer formed in the wiring groove and the wiring hole from the copper plating layer.

Subsequently, the semiconductor substrate W from which the copper plating layer on the surface of the semiconductor substrate W has been removed by leaving the copper plating layer formed on the wiring portion formed of the wiring groove and the wiring hole from the copper plating layer as described above is washed with water. It is transferred to a tank 610 and washed there with water. Subsequently, in the pretreatment tank 611, pretreatment for performing lid plating described later is performed. The semiconductor substrate W for which the pretreatment has been completed is transferred to the lid plating tank 612, and a protective film is formed on the copper plating layer formed on the wiring portion in the lid plating tank 612. As this protective film, for example, a Ni-B electroless plating bath is used.
After forming the protective film, the semiconductor substrate W is washed with water tanks 606, 6
It is washed with water at 07 and further dried in a drying tank 608. Then, the upper portion of the protective film formed on the copper plating layer is attached to the CMP portion 6
After polishing with 15, flattening, washing with water in washing tanks 613 and 614, and drying in a drying tank 608, the semiconductor substrate W is stored in the substrate cassette 609-1 of the carry-out section 609.

FIG. 40 is a diagram showing a planar structure of another substrate processing apparatus for wiring a semiconductor substrate. As shown in the figure, in this substrate processing apparatus, a robot 616 is arranged in the center, and a copper plating tank 602, a water washing tank 603, and a water washing tank 6 for performing copper plating in a range reached by a robot arm 616-1 around the robot 616.
04, CMP section 605, lid plating tank 612, drying tank 60
8 and the load / unload unit 617 are arranged to constitute one device. A semiconductor substrate carry-in unit 601 and a carry-out unit 609 are disposed adjacent to the load / unload unit 617.

In the substrate processing apparatus for semiconductor substrate wiring having the above structure, the semiconductor substrate on which the wiring is not plated is loaded / unloaded from the carry-in portion 601 of the semiconductor substrate.
7, the semiconductor substrate is transferred to the robot arm 616-
1 is received and transferred to a copper plating tank 602, where a copper plating layer is formed on the surface of the semiconductor substrate including the wiring portion including wiring grooves and wiring holes. The semiconductor substrate on which the copper plating layer is formed is CMP by the robot arm 616-1.
Then, the excess CMP layer on the surface of the semiconductor substrate W is removed, leaving the copper plating layer formed in the wiring portion including the wiring groove and the wiring hole from the copper plating layer in the CMP portion 605.

The semiconductor substrate from which the excess copper plating layer on the surface has been removed is washed by the robot arm 616-1 in the water washing tank 60.
After being transferred to No. 4 and washed with water, it is transferred to a pretreatment tank 611, and pretreatment for lid plating is performed in the pretreatment tank 611. The preprocessed semiconductor substrate is transferred to the lid plating tank 612 by the robot arm 616-1, and is protected on the copper plating layer formed in the wiring portion including the wiring groove and the wiring hole in the lid plating tank 612. Form a film. The semiconductor substrate on which the protective film is formed is transferred to the water washing tank 604 by the robot arm 616-1 and subjected to water washing treatment there,
After being transferred to the drying tank 608 and dried, it is transferred to the load / unload unit 617. The semiconductor substrate on which the wiring plating has been completed is transferred to the carry-out section 609.

FIG. 41 is a diagram showing a planar structure of another semiconductor substrate processing apparatus. This semiconductor substrate processing apparatus includes a load / unload unit 701, a copper plating unit 702, a first robot 703, a third cleaning machine 704, a reversing machine 705,
Inversion machine 706, second cleaning machine 707, second robot 70
8, a first cleaning machine 709, a first polishing device 710 and a second polishing device 711 are arranged.
In the vicinity of the first robot 703, a pre- and post-plating film thickness measuring device 712 for measuring the film thickness before and after plating, and a dry film thickness measuring device 7 for measuring the film thickness of the semiconductor substrate W in a dry state after polishing.
13 are arranged.

First polishing device (polishing unit) 7
10 is a polishing table 710-1 and a top ring 710.
-2, top ring head 710-3, film thickness measuring machine 71
It is equipped with 0-4 and pushers 710-5. The second polishing device (polishing unit) 711 includes a polishing table 711-1, a top ring 711-2, a top ring head 711-3, a film thickness measuring machine 711-4, and a pusher 711-5.

A loading / unloading section 701 is provided with a cassette 701-1 containing a semiconductor substrate W having contact holes and wiring grooves formed thereon and having a seed layer formed thereon.
Place it on the load port. The first robot 703 takes out the semiconductor substrate W from the cassette 701-1 and carries it into the copper plating unit 702 to form a copper plating film. At that time, the film thickness of the seed layer is measured by the film thickness measuring device before and after plating 712. The copper plating film is formed by first performing hydrophilic treatment on the surface of the semiconductor substrate W and then performing copper plating. After the copper plating film is formed, the copper plating unit 702 performs rinsing or cleaning. If you have time, you can dry it.

The first robot 703 uses the copper plating unit 7
When the semiconductor substrate W is taken out of No. 02, the film thickness of the copper plating film is measured by the film thickness measuring device before and after plating 712. The measurement result is recorded as recording data of the semiconductor substrate in a recording device (not shown), and the copper plating unit 70 is used.
It is also used to judge 2 abnormalities. After the film thickness is measured, the first robot 703 transfers the semiconductor substrate W to the reversing machine 705 and reverses it (the surface on which the copper plating film is formed faces down). Polishing by the first polishing device 710 and the second polishing device 711 includes a series mode and a parallel mode. The series mode polishing will be described below.

The series mode polishing is polishing in which the primary polishing is performed by the polishing device 710 and the secondary polishing is performed by the polishing device 711. The second robot 708 picks up the semiconductor substrate W on the reversing device 705, and places the semiconductor substrate W on the pusher 710-5 of the polishing device 710. The top ring 710-2 adsorbs the semiconductor substrate W on the pusher 710-5, abuts and presses the copper plating film formation surface of the semiconductor substrate W against the polishing surface of the polishing table 710-1 to perform the primary polishing. In the primary polishing, the copper plating film is basically polished. The polishing surface of the polishing table 710-1 is
It is made of foamed polyurethane such as IC1000, or one in which abrasive grains are fixed or impregnated. The copper plating film is polished by the relative movement between the polishing surface and the semiconductor substrate W.

After completion of polishing of the copper plating film, the top ring 7
At 10-2, the semiconductor substrate W is returned onto the pusher 710-5. The second robot 708 picks up the semiconductor substrate W and puts it in the first cleaning machine 709. At this time, pusher 7
There is a case where a chemical solution is sprayed on the front surface and the back surface of the semiconductor substrate W on 10-5 to remove particles or make them difficult to stick.

After the cleaning is completed in the first cleaning machine 709, the semiconductor substrate W is picked up by the second robot 708, and the semiconductor substrate W is placed on the pusher 711-5 of the second polishing device 711. The top ring 711-2 adsorbs the semiconductor substrate W on the pusher 711-5,
The surface on which the barrier layer is formed is brought into contact with and pressed against the polishing surface of the polishing table 711-1 to perform secondary polishing. In this secondary polishing, the barrier layer is polished. However, in some cases, the copper film and oxide film remaining after the above primary polishing are also polished.

The polishing surface of the polishing table 711-1 is IC
It is made of foamed polyurethane such as 1000, or one in which abrasive grains are fixed or impregnated, and is polished by relative movement between the polishing surface and the semiconductor substrate W. At this time, silica, alumina, ceria, or the like is used for the abrasive grains or the slurry. The chemical solution is adjusted depending on the type of film to be polished.

The end point of the secondary polishing is detected by measuring the film thickness of the barrier layer using an optical film thickness measuring device and detecting the film thickness becoming 0 or the surface of the insulating film made of SiO _2. To do. Further, as the film thickness measuring device 711-4 provided in the vicinity of the polishing table 711-1, a film thickness measuring device with an image processing function is used to measure the oxide film and leave it as a processing record of the semiconductor substrate W or 2 It is determined whether or not the semiconductor substrate W after the next polishing can be transferred to the next step. Further, if the secondary polishing end point has not been reached, re-polishing is performed, and if polishing is performed beyond the specified value due to some abnormality, semiconductor substrate processing is performed so that the next polishing is not performed so that defective products are not increased. Stop the device.

After completion of the secondary polishing, the top ring 711-2
Then, the semiconductor substrate W is moved to the pusher 711-5. The semiconductor substrate W on the pusher 711-5 is picked up by the second robot 708. At this time, pusher 711-
In some cases, the chemical solution may be sprayed onto the front surface and the back surface of the semiconductor substrate W to remove particles or make it hard to stick.

The second robot 708 carries the semiconductor substrate W into the second cleaning machine 707 and cleans it. Second washing machine 70
The configuration of 7 is also the same as that of the first cleaning machine 709. The surface of the semiconductor substrate W is scrub-cleaned with a PVA sponge roll using a cleaning liquid obtained by adding a surfactant, a chelating agent, and a pH adjusting agent to pure water, mainly for removing particles. On the back surface of the semiconductor substrate W, from the nozzle to the DHF
Etc., a strong chemical solution is ejected to etch the diffused copper, or if there is no problem of diffusion, scrub cleaning with a PVA sponge roll is performed using the same chemical solution as the surface.

After the cleaning is completed, the semiconductor substrate W is picked up by the second robot 708, transferred to the reversing machine 706, and reversed by the reversing machine 706. The inverted semiconductor substrate W is picked up by the first robot 703 and placed in the third cleaning machine 704. In the third cleaning machine 704, the surface of the semiconductor substrate W is cleaned by jetting megasonic water excited by ultrasonic vibration. At that time, deionized water is mixed with a surfactant, a chelating agent, p
The surface of the semiconductor substrate W may be washed with a known pencil-type sponge using a washing liquid containing an H adjusting agent. afterwards,
The semiconductor substrate W is dried by spin drying. When the film thickness is measured by the film thickness measuring device 711-4 provided in the vicinity of the polishing table 711-1 as described above, the film is directly stored in the cassette mounted on the unload port of the loading / unloading unit 701.

FIG. 42 is a diagram showing a planar structure of another semiconductor substrate processing apparatus. FIG. 41 of this semiconductor substrate processing apparatus
41 is different from the semiconductor substrate processing apparatus shown in FIG. 41 in that instead of the copper plating unit 702 shown in FIG.
This is the point where 50 is provided. The cassette 701-1 containing the semiconductor substrate W on which the copper film is formed is placed on the load / unload unit 701. The semiconductor substrate W is a cassette 701.
−1, and is transported to the first polishing device 710 or the second polishing device 711, where the surface of the copper film is polished. After completion of this polishing, the semiconductor substrate W
Are conveyed to the first cleaning machine 709 and cleaned.

The semiconductor substrate W cleaned by the first cleaning machine 709 is conveyed to the lid plating unit 750, where a protective film is formed on the surface of the copper plating film, whereby the copper plating film is oxidized in the atmosphere. Is prevented. The lid-plated semiconductor substrate W is transferred from the lid plating unit 750 to the second cleaning machine 707 by the second robot 708, where it is washed with pure water or deionized water. The semiconductor substrate W after the cleaning is returned to the cassette 701-1 placed on the load / unload unit 701.

FIG. 43 is a diagram showing a planar structure of still another semiconductor substrate processing apparatus. This semiconductor substrate processing apparatus is different from the semiconductor substrate processing apparatus shown in FIG. 42 in that instead of the first cleaning machine 709 shown in FIG.
This is the point where 1 is provided. As described above, the semiconductor substrate W polished by the first polishing apparatus 710 or the second polishing apparatus 711 and cleaned by the second cleaning machine 707.
Is transported to the lid plating unit 750, where the surface of the copper plating film is subjected to lid plating. The lid-plated semiconductor substrate W is transferred from the lid plating unit 750 to the third cleaning machine 704 by the first robot 703, and is cleaned there.

The semiconductor substrate W cleaned by the first cleaning machine 709 is transferred to the annealing unit 751 and annealed there. As a result, the copper plating film is alloyed to improve the electron migration resistance of the copper plating film. The annealed semiconductor substrate W is conveyed from the annealing unit 751 to the second cleaning machine 707, where it is cleaned with pure water or deionized water. The semiconductor substrate W after the cleaning is returned to the cassette 701-1 placed on the load / unload unit 701.

FIG. 44 is a diagram showing another planar arrangement configuration of the substrate processing apparatus. In FIG. 44, the same reference numerals as those in FIG. 41 denote the same or corresponding parts. This substrate polishing apparatus is arranged so as to approach the first polishing apparatus 710 and the second polishing apparatus 711 and to pusher indexer 72.
5, the third cleaning machine 704 and the copper plating unit 70 are arranged.
2, substrate mounting tables 721 and 722 are arranged respectively, robots 723 are arranged near the first cleaning machine 709 and the third cleaning machine 704, and a robot 724 is arranged near the second cleaning machine 707 and the copper plating unit 702. Further, a dry state film thickness measuring device 713 is arranged in the vicinity of the load / unload unit 701 and the first robot 703.

In the substrate processing apparatus having the above structure, the first robot 703 takes out the semiconductor substrate W from the cassette 701-1 placed on the load port of the loading / unloading section 701, and measures the dry film thickness measuring machine 713. After the film thicknesses of the barrier layer and the seed layer are measured with, the semiconductor substrate W is placed on the substrate platform 721. When the dry film thickness measuring instrument 713 is provided in the hand of the first robot 703, the film thickness is measured there and placed on the substrate platform 721. The second robot 723 transfers the semiconductor substrate W on the substrate platform 721 to the copper plating unit 702 and forms a copper plating film. After the copper plating film is formed, the film thickness of the copper plating film is measured by a film thickness measuring device before and after plating 712. Then, the second robot 723 transfers the semiconductor substrate W to the pusher indexer 725 and mounts it thereon.

[Series Mode] In the series mode,
The top ring head 710-2 adsorbs the semiconductor substrate W on the pusher indexer 725, and the polishing table 71
The semiconductor substrate W is transferred to 0-1 and the semiconductor substrate W is pressed against the polishing surface on the polishing table 710-1 to perform polishing. The end point of polishing is detected by the same method as described above, and the semiconductor substrate W after polishing is finished.
Is transferred to and mounted on the pusher indexer 725 by the top ring head 710-2. Second robot 723
Then, the semiconductor substrate W is taken out, carried into the first cleaning machine 709 and cleaned, and subsequently transferred to the pusher indexer 725 and mounted.

The top ring head 711-2 adsorbs the semiconductor substrate W on the pusher indexer 725, transfers it to the polishing table 711-1, and presses the semiconductor substrate W against the polishing surface to perform polishing. The end point of polishing is detected by the same method as described above, and the semiconductor substrate W after completion of polishing is pushed by the top ring head 711-2 by the pusher indexer 72.
It is transferred to 5 and mounted. The third robot 724 picks up the semiconductor substrate W, measures the film thickness with the film thickness measuring machine 726, and then carries it into the second cleaning machine 707 and cleans it. Then the third
It is carried into the cleaning machine 704, where it is cleaned and then dried by spin dry, and then the semiconductor substrate W is picked up by the third robot 724 and placed on the substrate platform 722.

[Parallel Mode] In the parallel mode,
The top ring head 710-2 or 711-2 adsorbs the semiconductor substrate W on the pusher indexer 725, transfers it to the polishing table 710-1 or 711-1, and the polishing surface on the polishing table 710-1 or 711-1. Then, the semiconductor substrate W is pressed and polished. After the film thickness is measured, the semiconductor substrate W is picked up by the third robot 724 and placed on the substrate platform 722. The first robot 703 transfers the semiconductor substrate W on the substrate platform 722 to the dry film thickness measuring machine 713, measures the film thickness, and then returns it to the cassette 701-1 of the loading / unloading unit 701.

FIG. 45 is a diagram showing another planar arrangement configuration of the substrate processing apparatus. This substrate processing apparatus is a substrate processing apparatus that forms a seed layer and a copper plating film on a semiconductor substrate W on which a seed layer is not formed and then polishes the circuit wiring to form circuit wiring. In this substrate polishing apparatus, a pusher indexer 725 is arranged close to the first polishing apparatus 710 and the second polishing apparatus 711, and the substrate mounting table 721 and the seed layer deposition unit 727 are provided in the vicinity of the second cleaning machine 707 and the seed layer deposition unit 727, respectively. 722 is disposed, and the seed layer deposition unit 72 is disposed.
7 and the robot 723 approaching the copper plating unit 702
The robot 724 in the vicinity of the first cleaning machine 709 and the second cleaning machine 707, and the dry film thickness measuring machine 7 in the vicinity of the loading / unloading section 701 and the first robot 703.
13 are arranged.

The cassette 70 placed on the load port of the load / unload unit 701 by the first robot 703.
The semiconductor substrate W on which the barrier layer is formed is taken out from 1-1, and is placed on the substrate platform 721. Next, the second robot 723 uses the seed layer deposition unit 72 for the semiconductor substrate W.
It is conveyed to 7 and a seed layer is formed into a film. The seed layer is formed by electroless plating. The second robot 723 measures the film thickness measuring device 71 before and after plating the semiconductor substrate on which the seed layer is formed.
At 2, measure the thickness of the seed layer. After the film thickness is measured, it is carried into the copper plating unit 702 to form a copper plating film.

After forming the copper plating film, the film thickness is measured,
Transfer to pusher indexer 725. The top ring 710-2 or 711-2 adsorbs the semiconductor substrate W on the pusher indexer 725, and the polishing table 71
Transfer to 0-1 or 711-1 and polish. After polishing, the top ring 710-2 or 711-2 transfers the semiconductor substrate W to the film thickness measuring device 710-4 or 711-4, measures the film thickness, and transfers the semiconductor substrate W to the pusher indexer 725 for mounting.

Next, the third robot 724 picks up the semiconductor substrate W from the pusher indexer 725,
It is carried into the washing machine 709. The third robot 724 is the first
Picking up the cleaned semiconductor substrate W from the cleaning machine 709,
The semiconductor substrate that has been carried into the second cleaning machine 707, washed and dried is placed on the substrate platform 722. Next, the first robot 703 picks up the semiconductor substrate W, measures the film thickness with the dry film thickness measuring machine 713, and places the cassette 701-1 mounted on the unload port of the load / unload unit 701.
To store.

Also in the substrate processing apparatus shown in FIG. 45, a barrier layer, a seed layer and a copper plating film are formed on the semiconductor substrate W in which the contact holes or grooves of the circuit pattern are formed and polished to form the circuit wiring. can do. Cassette 701 accommodating semiconductor substrate W before formation of barrier layer
1 is mounted on the load port of the load / unload unit 701. Then, the first robot 703 takes out the semiconductor substrate W from the cassette 701-1 placed on the load port of the load / unload unit 701 and places it on the substrate platform 721. Next, the second robot 723 conveys the semiconductor substrate W to the seed layer forming unit 727 and forms a barrier layer and a seed layer. The barrier layer and the seed layer are formed by electroless plating. The second robot 723 measures the film thickness of the barrier layer and the seed layer formed on the semiconductor substrate W with the film thickness measuring device before and after plating 712. After the film thickness is measured, it is carried into the copper plating unit 702 to form a copper plating film.

FIG. 46 is a diagram showing another planar arrangement configuration of the substrate processing apparatus. This substrate processing apparatus includes a barrier layer film forming unit 811, a seed layer film forming unit 812, a plating unit 813, an annealing unit 814, a first cleaning unit 815, a bevel / back surface cleaning unit 816, a lid plating unit 817, and a second cleaning unit. 818, first aligner / film thickness measuring instrument 841, second aligner / film thickness measuring instrument 842, first substrate reversing machine 843, second substrate reversing machine 84
4, substrate temporary placing table 845, third film thickness measuring device 846, load / unload unit 820, first polishing device 82
1, second polishing device 822, first robot 83
In this configuration, the first robot 2, the second robot 832, the third robot 833, and the fourth robot 834 are arranged. The film thickness measuring devices 841, 842 and 846 are units, and can be replaced because they have the same size as the front dimension of other units (units for plating, cleaning, annealing, etc.). In this example, an electroless Ru plating device can be used as the barrier layer film forming unit 811, an electroless copper plating device can be used as the seed layer film forming unit 812, and an electrolytic plating device can be used as the plating unit 813.

FIG. 47 is a flow chart showing the flow of each process in this substrate processing apparatus. Each process in this apparatus will be described according to this flowchart. First, the semiconductor substrate taken out from the cassette 820a placed on the load / unload unit 820 by the first robot 831 is placed inside the first aligner / film thickness measuring unit 841 with the surface to be plated facing up. Here, in order to determine the reference point of the position for measuring the film thickness, after performing notch alignment for film thickness measurement, film thickness data of the semiconductor substrate before the copper film formation is obtained.

Next, the semiconductor substrate is used as the first robot 831.
Thus, the film is conveyed to the barrier layer film forming unit 811. The barrier layer forming unit 811 is a device for forming a barrier layer on a semiconductor substrate by electroless Ru plating, and forms Ru as a copper diffusion preventing film on an interlayer insulating film (eg, SiO ₂ ) of the semiconductor device. . The semiconductor substrate discharged through the washing and drying steps is conveyed to the first aligner / film thickness measuring unit 841 by the first robot 831 and the film thickness of the semiconductor substrate, that is, the film thickness of the barrier layer is measured.

The semiconductor substrate whose film thickness has been measured is carried into the seed layer forming unit 812 by the second robot 832, and the seed layer is formed on the barrier layer by electroless copper plating. The semiconductor substrate discharged through the cleaning and drying steps is transferred to the second aligner / film thickness measuring device 842 to determine the notch position before being transferred to the plating unit 813 which is the impregnation plating unit by the second robot 832. It is transferred and the notch for copper plating is aligned. Here, the film thickness of the semiconductor substrate before forming the copper film may be remeasured, if necessary.

The semiconductor substrate on which the notch alignment has been completed is carried to the plating unit 813 by the third robot 833 and copper plating is performed. The semiconductor substrate discharged through the cleaning and drying steps is conveyed by the third robot 833 to the bevel / back surface cleaning unit 816 in order to remove an unnecessary copper film (seed layer) at the end of the semiconductor substrate. In the bevel / back surface cleaning unit 816, the bevel is etched for a preset time, and the copper attached to the back surface of the semiconductor substrate is cleaned with a chemical solution such as hydrofluoric acid. At this time, before transporting to the bevel / back surface cleaning unit 816,
The film thickness of the semiconductor substrate is measured by the second aligner / film thickness measuring device 842 to obtain the value of the copper film thickness formed by plating, and the bevel etching time is arbitrarily changed according to the result. You may etch. The region to be etched by bevel etching is a region where the circuit is not formed in the peripheral portion of the substrate or a region where the circuit is not finally used as a chip. This area includes the bevel portion.

Cleaning with the bevel / back surface cleaning unit 816,
The semiconductor substrate discharged through the drying process is conveyed to the substrate reversing machine 843 by the third robot 833, reversed by the substrate reversing machine 843, and the surface to be plated is turned downward, and then the fourth robot 834. It is put into the annealing unit 814 to stabilize the wiring part. The second aligner / film thickness measuring unit 84 before and / or after the annealing treatment
Then, the film thickness of the copper film formed on the semiconductor substrate is measured. Then, the semiconductor substrate is carried into the first polishing apparatus 821 by the fourth robot 834, and the copper layer and the seed layer of the semiconductor substrate are polished.

At this time, desired abrasive grains are used, but in order to prevent dishing and to obtain flatness of the surface,
Fixed abrasive grains can also be used. After the completion of the first polishing, the semiconductor substrate is transferred to the first cleaning unit 815 by the fourth robot 834 and cleaned. This wash is
This is scrub cleaning in which a roll having a length substantially the same as the diameter of the semiconductor substrate is arranged on the front surface and the back surface of the semiconductor substrate, and the semiconductor substrate and the roll are rotated and purified water or deionized water is caused to flow.

After the completion of the first cleaning, the semiconductor substrate is carried into the second polishing device 822 by the fourth robot 834, and the barrier layer on the semiconductor substrate is polished. On this occasion,
Although desired abrasive grains or the like are used, fixed abrasive grains may be used to prevent dishing and to obtain flatness of the surface. After the second polishing is completed, the semiconductor substrate is again removed by the fourth robot 834 from the first cleaning unit 815.
It is transported to and scrubbed. After the cleaning is completed, the semiconductor substrate is transferred to the second substrate reversing machine 84 by the fourth robot 834.
4 and then inverted, the surface to be plated is directed upward, and further the third robot 833 causes the temporary substrate holder 845.
Placed in.

The semiconductor substrate is transferred from the temporary substrate rest 845 to the lid plating unit 817 by the second robot 832, and nickel / boron plating is performed on the copper surface for the purpose of preventing copper from being oxidized by the atmosphere. The semiconductor substrate plated with the lid is covered by the second robot 832 in the lid plating unit 81.
It is carried into the third film thickness measuring device 846 from 7 and the copper film thickness is measured. Then, the semiconductor substrate is carried into the second cleaning unit 818 by the first robot 831 and cleaned with pure water or deionized water. The semiconductor substrate after cleaning is loaded and unloaded by the robot 1 in the platform 1
It is returned to the inside of the cassette 820a placed on the 20. Aligner and film thickness measuring device 841 and aligner and film thickness measuring device 84
2 measures the film thickness and the positioning of the substrate notch.

The bevel / back surface cleaning unit 816 can simultaneously perform edge (bevel) copper etching and back surface cleaning, and can suppress the growth of a natural oxide film of copper on a circuit forming portion on the substrate surface. FIG. 48 shows a schematic view of the bevel / back surface cleaning unit 816. As shown in FIG. 48, the bevel / back surface cleaning unit 816 is located inside the bottomed cylindrical waterproof cover 920, and the substrate W is face-up and spin chucked at a plurality of positions along the circumferential direction of the peripheral edge of the substrate W. A substrate holding portion 922 which is held horizontally by 921 and is rotated at a high speed, and a center nozzle 92 which is arranged substantially above the central portion on the front surface side of the substrate W held by the substrate holding portion 922.
4 and an edge nozzle 926 arranged above the peripheral edge of the substrate W. The center nozzle 924 and the edge nozzle 926 are arranged facing downward, respectively. Further, a back nozzle 928 is arranged facing upward and is positioned below a substantially central portion on the back surface side of the substrate W. The edge nozzle 926 is configured to be movable in the diameter direction and the height direction of the substrate W.

The moving width L of the edge nozzle 926 allows arbitrary positioning from the outer peripheral end surface of the substrate toward the central portion, and is adjusted according to the size of the substrate W and the purpose of use.
Enter the set value. Usually, the edge cut width C is set in the range of 2 mm to 5 mm, and if the amount of the liquid flowing from the back surface to the front surface is equal to or higher than the number of rotations, the copper film within the set cut width C is removed. be able to.

Next, a cleaning method using this cleaning device will be described. First, with the substrate held horizontally by the substrate holding unit 922 via the spin chuck 921, the semiconductor substrate W is horizontally rotated integrally with the substrate holding unit 922. In this state, the acid solution is supplied from the center nozzle 924 to the central portion on the front surface side of the substrate W. The acid solution may be a non-oxidizing acid, for example, hydrofluoric acid, hydrochloric acid, sulfuric acid, citric acid, oxalic acid, or the like. On the other hand, the oxidant solution is continuously or intermittently supplied from the edge nozzle 926 to the peripheral portion of the substrate W. As the oxidant solution, one of ozone water, hydrogen peroxide water, nitric acid water, sodium hypochlorite water, or the like is used, or a combination thereof is used.

As a result, in the region of the edge cut width C at the peripheral edge of the semiconductor substrate W, the copper film and the like formed on the upper surface and the end surface are rapidly oxidized by the oxidant solution and simultaneously supplied from the center nozzle 924 to the substrate. Is removed by dissolution with an acid solution that spreads over the entire surface of the. Thus, by mixing the acid solution and the oxidizer solution at the peripheral edge of the substrate, a sharper etching profile can be obtained as compared with the case where the mixed water of them is supplied in advance from the nozzle. At this time, the copper etching rate is determined by their concentrations. Further, when a natural oxide film of copper is formed on the circuit formation portion on the surface of the substrate, this natural oxide is immediately removed by an acid solution that spreads over the entire surface of the substrate as the substrate rotates, and grows. There is no such thing. The center nozzle 924
After stopping the supply of the acid solution from the edge nozzle 926
By stopping the supply of the oxidant solution from, the silicon exposed on the surface can be oxidized and the adhesion of copper can be suppressed.

On the other hand, the oxidant solution and the silicon oxide film etching agent are simultaneously or alternately supplied from the back nozzle 928 to the central portion of the back surface of the substrate. As a result, the copper or the like that is metallically attached to the back surface of the semiconductor substrate W can be removed together with the silicon of the substrate by oxidizing with the oxidizing agent solution and etching with the silicon oxide film etching agent. It should be noted that this oxidant solution is preferably the same as the oxidant solution supplied to the surface in order to reduce the kinds of chemicals. Further, hydrofluoric acid can be used as the silicon oxide film etching agent, and the types of chemicals can be reduced by using hydrofluoric acid for the acid solution on the surface side of the substrate. Thus, if the supply of the oxidant is stopped first, a hydrophobic surface is obtained, and if the solution of the etchant is stopped first, a saturated surface (hydrophilic surface) is obtained, and the back surface is adjusted according to the demand of the subsequent process. You can also

Thus, the acid solution, that is, the etching solution is supplied to the substrate to remove the metal ions remaining on the surface of the substrate W, and then pure water is supplied to replace the pure water to remove the etching solution. Then, spin drying is performed. In this way, the edge cut width C of the peripheral portion of the semiconductor substrate surface is
This process can be completed within 80 seconds, for example, by simultaneously removing the copper film inside and removing the copper contamination on the back surface. In addition, the edge cut width of the edge is arbitrary (2 mm to 5 mm
However, the time required for etching does not depend on the cut width.

Performing the annealing treatment before the CMP step after plating has a good effect on the subsequent CMP treatment and the electrical characteristics of the wiring. When the surface of a wide wiring (unit of several μm) was observed after the CMP process without annealing, many defects such as microvoids were found, and the electrical resistance of the entire wiring was increased. Increase was improved. Since no void was found in the thin wiring without annealing, it is considered that the degree of grain growth is involved. In other words, grain growth does not occur easily with thin wiring, but with ultra-fine wiring that is invisible to the SEM (scanning electron microscope) in the plating film in the process of grain growth accompanying annealing treatment with grain growth in wide wiring. It can be inferred that the pores gathered and moved upwards, resulting in the formation of microvoid depressions in the upper portion of the wiring.
As the annealing conditions of the annealing unit, hydrogen is added to the gas atmosphere (2% or less), and the temperature is 300 to 400 ° C.
The above effect was obtained in about 1 to 5 minutes.

51 and 52 show the annealing unit 8
14 is shown. This annealing unit 814
Is located inside a chamber 1002 having a gate 1000 for loading and unloading the semiconductor substrate W.
Is heated to, for example, 400 ° C. hot plate 1004
Then, cool plates 1006 for cooling the semiconductor substrate W by flowing cooling water, for example, are arranged above and below. In addition, a plurality of elevating pins 1008 that penetrate the inside of the cool plate 1006 and extend in the up-down direction and that mount and hold the semiconductor substrate W are vertically arranged. Further, a gas introducing pipe 1010 for introducing an oxidation preventing gas between the semiconductor substrate W and the hot plate 1008 during annealing, and a gas introduced through the gas introducing pipe 1010 and flowing between the semiconductor substrate W and the hot plate 1004. A gas exhaust pipe 1012 for exhausting the gas is arranged at a position facing each other with the hot plate 1004 interposed therebetween.

The gas introducing pipe 1010 has the filter 1 inside.
N flowing in the N ₂ gas introduction passage 1016 having 014a
₂ gas and, mixer 1020 and a _{H 2} gas flowing through the _{H 2} gas introduction passage 1018 having a filter 1014b therein
Are connected to a mixed gas introducing passage 1022 through which the gases mixed by the mixer 1020 flow.

As a result, the semiconductor substrate W carried into the chamber 1002 through the gate 1000 is held by the lift pins 1008, and the lift pins 1008 are held by the lift pins 1008.
08 holding semiconductor substrate W and hot plate 1004
Is increased until the distance between and becomes, for example, about 0.1 to 1.0 mm. In this state, the semiconductor substrate W is heated to, for example, 400 ° C. via the hot plate 1004, and at the same time, an oxidation preventing gas is introduced from the gas introducing pipe 1010 so that the semiconductor substrate W and the hot plate 1004 are separated from each other. Is exhausted from the gas exhaust pipe 1012. As a result, the semiconductor substrate W is annealed while preventing oxidation, and this annealing is continued for, for example, several tens of seconds to 60 seconds to complete the annealing. The substrate heating temperature is selected to be 100 to 600 ° C.

After the annealing is completed, the lift pins 1008 are lowered until the distance between the semiconductor substrate W held by the lift pins 1008 and the cool plate 1006 becomes, for example, about 0 to 0.5 mm. In this state, cool plate 100
By introducing cooling water into the semiconductor substrate 6, the semiconductor substrate is cooled until the temperature of the semiconductor substrate W becomes 100 ° C. or lower, for example, for about 10 to 60 seconds, and the semiconductor substrate after completion of this cooling is transported to the next step. . In this example, as the oxidation preventing gas, the mixed gas in which the N ₂ gas and the H ₂ gas of several% are mixed is allowed to flow, but only the N ₂ gas may be allowed to flow.

FIG. 49 is a schematic block diagram of an electroless plating apparatus. As shown in FIG. 49, this electroless plating apparatus has a holding means 911 for holding the semiconductor substrate W, which is a member to be plated, on its upper surface, and a plated surface (upper surface) of the semiconductor substrate W held by the holding means 911. And a shower head 941 for supplying a plating solution to the surface to be plated of the semiconductor substrate W whose peripheral portion is sealed by the barrier member 931.
The electroless plating apparatus is further installed near the outer periphery of the upper part of the holding means 911, and a cleaning liquid supply means 951 for supplying a cleaning liquid to the surface to be plated of the semiconductor substrate W, and a recovery container for recovering the discharged cleaning liquid or the like (plating waste liquid). 961, a plating solution recovery nozzle 965 that sucks and recovers the plating solution held on the semiconductor substrate W, and a motor M that rotationally drives the holding means 911. Hereinafter, each member will be described.

The holding means 911 is provided with a substrate mounting portion 913 for mounting and holding the semiconductor substrate W on its upper surface.
The substrate mounting portion 913 is configured to mount and fix the semiconductor substrate W, and specifically, a vacuum suction mechanism (not shown) that vacuum-sucks the semiconductor substrate W on the back surface side thereof is installed. . On the other hand, on the back surface side of the substrate platform 913, a back surface heater 915 that is planar and warms the surface to be plated of the semiconductor substrate W from the lower surface side to keep it warm is installed. The back surface heater 915 is composed of, for example, a rubber heater. The holding means 911 is configured to be rotationally driven by the motor M and can be moved up and down by an elevating means (not shown). The dam member 931 has a tubular shape, and a seal portion 933 that seals the outer peripheral edge of the semiconductor substrate W is provided in the lower portion of the dam member 931 and is installed so as not to move up and down from the illustrated position.

The shower head 941 has a structure in which a large number of nozzles are provided at the tip of the shower head 941 to disperse the supplied plating solution in a shower shape and supply the plated surface of the semiconductor substrate W substantially uniformly. The cleaning liquid supply means 951 has a structure in which the cleaning liquid is ejected from the nozzle 953. The plating solution recovery nozzle 965 is configured to be vertically movable and swivel, and its tip is lowered inside the dam member 931 at the peripheral portion of the upper surface of the semiconductor substrate W to suck the plating solution on the semiconductor substrate W. Is configured.

Next, the operation of this electroless plating apparatus will be described. First, the holding means 911 is lowered from the state shown in the figure to form a gap of a predetermined size between the holding means 911 and the dam member 931 and the semiconductor substrate W is placed and fixed on the substrate placing part 913. As the semiconductor substrate W, for example, a φ8 inch substrate is used. Next, the holding means 911 is raised and its upper surface is covered with the dam member 9 as shown in the figure.
The lower surface of the semiconductor substrate 31 is brought into contact with the outer surface of the semiconductor substrate W, and at the same time, the outer periphery of the semiconductor substrate W is sealed by the seal portion 933 of the dam member 931. At this time, the surface of the semiconductor substrate W is in an open state.

Next, the back surface heater 915 directly heats the semiconductor substrate W itself to, for example, raise the temperature of the semiconductor substrate W to 70 ° C. (maintain until the end of plating), and then from the shower head 941 to, for example, 50 ° C. The heated plating solution is jetted to pour the plating solution onto substantially the entire surface of the semiconductor substrate W. Since the surface of the semiconductor substrate W is surrounded by the dam member 931, the injected plating solution is entirely retained on the surface of the semiconductor substrate W. The amount of the plating solution supplied may be as small as 1 mm (about 30 ml) on the surface of the semiconductor substrate W. The depth of the plating solution held on the surface to be plated may be 10 mm or less, and as in this example, 1 m
m is also acceptable. If a small amount of the plating solution is supplied as in this example, the heating device for heating the plating solution may be small in size. In this example, the temperature of the semiconductor substrate W is set to 7
Since the temperature of the plating solution is heated to 0 ° C and 50 ° C,
The surface to be plated of the semiconductor substrate W is, for example, 60 ° C., which can be set to the optimum temperature for the plating reaction in this example. If the semiconductor substrate W itself is heated in this way, it is not necessary to raise the temperature of the plating solution, which requires a large amount of power consumption for heating, to be so high. This is preferable because it can prevent the material from changing. Since the power consumption for heating the semiconductor substrate W itself may be small and the amount of the plating solution accumulated on the semiconductor substrate W is small, the backside heater 915 can easily keep the temperature of the semiconductor substrate W, and the backside heater 915 can be kept warm. The capacity is small and the device can be made compact. In addition, the semiconductor substrate W
If a means for directly cooling itself is used, heating during plating
It is also possible to switch the cooling and change the plating conditions. Since a small amount of plating solution is held on the semiconductor substrate, temperature control can be performed with good sensitivity.

Then, the semiconductor substrate W is momentarily rotated by the motor M to uniformly wet the surface to be plated, and then the surface to be plated is plated while the semiconductor substrate W is stationary. Specifically, the semiconductor substrate W is set to 100 for 1 sec.
The surface to be plated of the semiconductor substrate W is uniformly wetted with the plating solution by rotating at rpm or less, and then allowed to stand still to perform electroless plating for 1 min. The instantaneous rotation time is at least 1
Set to 0 sec or less.

After the above plating process is completed, the tip of the plating solution recovery nozzle 965 is lowered to the vicinity of the inside of the dam member 931 at the peripheral portion of the surface of the semiconductor substrate W to suck the plating solution.
At this time, if the semiconductor substrate W is rotated at a rotation speed of, for example, 100 rpm or less, the plating solution remaining on the semiconductor substrate W can be collected by centrifugal force in the dam member 931 at the peripheral portion of the semiconductor substrate W, which improves efficiency. The plating solution can be recovered with good and high recovery rate. Then, the holding means 911 is lowered to separate the semiconductor substrate W from the dam member 931.
Of the cleaning liquid supply means 951 by starting the rotation of the nozzle 953.
The cleaning liquid (ultra pure water) is sprayed onto the surface to be plated of the semiconductor substrate W to cool the surface to be plated, and at the same time, the electroless plating reaction is stopped by diluting and cleaning. At this time, the dam member 931 may be simultaneously cleaned by applying the cleaning liquid sprayed from the nozzle 953 to the dam member 931. The plating waste liquid at this time is collected in the collection container 961 and discarded.

It should be noted that the plating solution used once is not reused but is disposable. As described above, the amount of the plating solution used in this apparatus can be made much smaller than the conventional one, so that the amount of the plating solution to be discarded is small even if it is not reused. In some cases, the plating solution recovery nozzle 965 may not be installed, and the used plating solution may be recovered together with the cleaning solution in the recovery container 961 as a plating waste solution. Then, the semiconductor substrate W is rotated at a high speed by the motor M to spin-dry, and then taken out from the holding means 911.

FIG. 50 is a schematic block diagram of another electroless plating apparatus. 50 is different from the above example in that instead of providing the back surface heater 915 in the holding means 911, a lamp heater (heating means) 917 is installed above the holding means 911, and the lamp heater 917 and the shower head are provided. This is the point that the 941-2 is integrated. That is, for example, a plurality of ring-shaped lamp heaters 917 having different radii
Are installed concentrically, and a large number of nozzles 943-2 of the shower head 941-2 are provided through the gaps between the lamp heaters 917.
Is opened like a ring. The lamp heater 917
As the above, it may be configured by a single spiral-shaped lamp heater, or may be configured by lamp heaters having other various structures and arrangements.

Even with this structure, the plating solution can be supplied from the nozzles 943-2 to the surface of the semiconductor substrate W to be plated in a substantially uniform manner, and the lamp heater 917 can heat the semiconductor substrate W. Insulation can be performed directly and evenly.
In the case of the lamp heater 917, not only the semiconductor substrate W and the plating solution but also the surrounding air is heated, so that the semiconductor substrate W also has a heat retaining effect.

In order to directly heat the semiconductor substrate W by the lamp heater 917, the lamp heater 917 having a relatively large power consumption is required. Therefore, instead of the lamp heater 917 having a relatively small power consumption, as shown in FIG. The semiconductor substrate W may be heated mainly by the back surface heater 915 by using the back surface heater 915 shown in the drawing, and the temperature of the plating solution and the surrounding air may be kept mainly by the lamp heater 917. Further, similarly to the above-described embodiment, the temperature control may be performed by providing a means for directly or indirectly cooling the semiconductor substrate W.

(Embodiment 1) As shown in FIG. 17, a silicon substrate 1 having an impurity diffusion region (not shown) formed therein.
An insulating layer 2 made of SiO ₂ having a depth D ₁ of about 1000 nm is formed thereon by a CVD method using TEOS, and then a well-known photoetching technique is used to form an insulating layer 2 having a depth of The wiring groove 4 of about 700 nm was formed. Subsequently, a barrier layer 5 made of a TaN / Ta film having a thickness of 15 nm was deposited on the surface of the insulating layer 2 including the wiring groove 4 by a sputtering vapor deposition method, and then a seed layer 7 was formed thereon. Then, by the electrolytic copper plating method,
A sample was prepared in which a copper film 6 having a thickness T ₁ of about 900 nm was deposited on the substrate including the wiring groove 4. At this time, the copper film 6 on the surface of the substrate has the largest thickness of about 900 nm in the local area where the narrow wiring grooves 4 are gathered, and the minimum thickness of about 400 nm at the upper part of the groove of the wide opening surface. Difference D is about 500n
It was m.

This sample was polished by the polishing apparatus 10 shown in FIG.
While holding the copper-plated surface downward with the substrate holding portion 16a of a, the sample and the polishing tool 22 are rotated in the opposite directions at a rotation speed of 90 rpm, respectively, and 300 g / c is applied to the polishing surface.
A polishing pressure of m ² was applied, and the copper film 6 of the sample
The first polishing was performed while using electrolytic polishing with the anode as the anode.

As a polishing liquid, 1.0% ammonium oxalate and 0.5% (85%) phosphoric acid were dissolved in pure water, and ammonia water was added to adjust the pH to 7.5. Of 40 nm colloidal silica 3.5%, 0.1% 8-hydroxyquinoline, 0.03% phenacetin is used, and the polishing solution is supplied so that the polishing surface of the substrate is immersed in this polishing solution. While polishing. The temperature of the polishing liquid was adjusted so that the polishing surface during operation was 25 ° C ± 1 ° C.

Here, as a current to be passed between the copper film 6 of the sample and the cathode plate 20, a current having a current density per surface area of copper on the substrate of 2 A / dm ² is passed for 10 × 10 ⁻³ seconds. However, a pulse current that similarly stops for 10 × 10 ⁻³ seconds was used. As a result of continuing the polishing for 60 seconds, the excess copper film 6 deposited on the substrate was polished from 900 nm to about 300 nm, and the maximum step was flattened from 500 nm to 100 nm or less.

Next, this sample was polished by the polishing apparatus 1 shown in FIG.
It moved to 0b and the 2nd polish was performed. At this time, the polishing device 1
The operating conditions of 0b and the polishing liquid were the same as those described above, except that only the power supply was changed. That is, the polishing apparatus 10b was operated, and after the polishing of the copper surface was started, a voltage of 50 V was immediately applied between the cathode rod 40 and the anode rod 42.
When this second polishing was continued for 60 seconds, all the excess copper film including the barrier layer 5 made of the TaN film was removed, and S
A substrate in which the iO ₂ insulating layer 2 and the surface of the copper film 6 in the wiring groove were flat was obtained.

Example 2 A sample manufactured by the same method as in Example 1 was held by the substrate holding portion 16a of the polishing apparatus 10a shown in FIG. 4 with the copper plating surface facing downward, and the sample W and the polishing tool 22 were held. The first polishing, in which the polishing pressure of 250 g / cm ² is applied to the polishing surface while rotating in opposite directions at a rotation speed of about 90 rpm, and electrolytic polishing with the copper film 6 of the sample as an anode in the polishing liquid described below is also used. I went.

As the polishing liquid, 1.0% ammonium oxalate and 2.0% (85%) phosphoric acid were dissolved in pure water, and the pH was adjusted to 8.5 by adding aqueous ammonia. Colloidal silica with a diameter of 40 nm 3.5%, 8-hydroxyquinoline 0.15%, nonionic surfactant 30 mg / L
The dissolved liquid was used, and the polishing liquid was continuously supplied so that the polishing surface of the sample was immersed in the polishing liquid.

As a current to be passed between the copper film 6 of the sample and the cathode plate 20, a current having a current density per surface area of copper on the sample of 3 A / dm ² was applied for 10 × 10 ⁻³ seconds,
Similarly, a pulse current of 10 × 10 ⁻³ seconds was used to energize for 45 seconds. When the composite electrolytic polishing was performed under these conditions, the excess copper film 6 deposited on the substrate was
From 900 nm to 300 nm, the level difference was reduced from 500 nm to 100 nm or less, and flattening proceeded.

Next, this sample was subjected to second polishing by a known method using a polishing liquid containing 8-hydroxyquinoline without using electrolysis in combination. That is, a hard and soft double-structured pad (for example, a substrate having a polishing surface held downward, mounted on an opposing turntable (for example,
Rodel Nitta IC1000 / SUBA400)
While a polishing pressure of 350 g / cm ² was applied between the ^two , and the following polishing liquids were continuously supplied while performing polishing at a speed of 70 rpm in the opposite directions to perform polishing.

Ammonium oxalate 1.0 was used as a polishing liquid.
%, Hydrogen peroxide 10%, colloidal silica 5.0% with an average particle size of 40 nm, nonionic surfactant 30 mg / L,
A composition having a composition of 0.05% 5-methylbenzotriazole and 0.1% 8-hydroxyquinoline was used. Copper film 6
The surface of was covered with a brittle film of oxine copper produced by the reaction of 8-hydroxyquinoline and copper, and the convex portions were selectively removed, so that the planarization was further promoted as the polishing progressed. .

Then, when the excess copper film 6 deposited on the substrate is polished and the barrier layer 5 made of a TaN / Ta film is exposed, the copper surface is covered with an inhibitor (5-
Methylbenzotriazole) protected by an organic acid,
Due to the action of hydrogen peroxide, the barrier layer 5 was smoothly etched back. As a result, when polishing is completed, Si
The O ₂ insulating layer 2 and the surface of the copper film 6 in the wiring groove are substantially flat, and as shown by phantom lines in FIG. 17, both the dishing depth A and the erosion depth B are within the range of 20 to 50 nm. I was able to suppress it.

Example 3 By the same method as in Example 1,
A sample prepared by depositing a copper film 6 having a film thickness T ₁ of about 1200 nm on a silicon substrate was prepared and polished in two steps. The maximum step D of the copper film 6 was 600 nm.

First, as in Example 2, the sample was held with the copper-plated surface facing downward on the substrate holder 16a of the polishing apparatus 10a shown in FIG. 4, and the sample and the polishing tool 22 were rotated in the opposite directions at about 90 rpm. While rotating at the rotation speed, 25
A polishing pressure of 0 g / cm ² was applied, and the first polishing was performed in the polishing solution described below, which also used electrolytic polishing with the copper film 6 of the sample as an anode. As the polishing liquid, 5.0% (85%) phosphoric acid was dissolved in pure water, pH was adjusted to 6.5 by adding aqueous ammonia, and γ-alumina 2.0 having an average particle diameter of 30 nm was used.
%, Also 40 nm colloidal silica 2.0%, 8-
Hydroxyquinoline 0.15%, nonionic surfactant 5
A solution containing 0 mg / L and 0.1% propylene urea dissolved therein was used.

Here, as a current to be passed between the copper film 6 of the sample and the cathode plate 20, a current having a current density per surface area of copper on the substrate of 4 A / dm ² is passed for 10 × 10 ⁻³ seconds. Then, the composite electropolishing was performed for 55 times using the pulse current similarly stopped for 10 × 10 ⁻³ seconds. As a result, the excess copper film 6 deposited on the substrate is polished from 1200 nm to 300 nm, and the polishing rate of the convex portion is 1100.
nm / min. The maximum step is 600 nm to 10
It was reduced to 0 nm or less, and a significant flattening effect was obtained.

Then, this sample was transferred to a separate CMP apparatus and further flattened and polished by using a polishing liquid containing 8-hydroxyquinoline without using electrolytic polishing together. That is, while pressing the sample held in the holder with the polishing surface facing downward on the polishing pad of the hard / soft structure mounted on the surface of the facing turntable at a pressure of 350 g / cm ² ,
Polishing was performed while rotating in opposite directions at a rotation speed of 70 rpm. At this time, the following polishing liquid was continuously supplied to the polishing surface.

Ammonium oxalate 1.0 was used as a polishing liquid.
%, Ammonium phosphate 0.5%, γ-alumina 2.0%,
Colloidal silica having an average particle diameter of 40 nm 3.0%, 8-
Hydroxyquinoline 0.1%, nonionic surfactant 30
mg / L, 5-methylbenzotriazole having a composition of 0.05% was used. A brittle film of oxine copper was formed on the surface of the copper, and the convex portions were selectively ground and removed, so that planarization was further promoted at the same time as the progress of polishing.

When the excess copper film 6 deposited on the substrate is polished to expose the barrier layer 5 made of TaN / Ta film,
The copper surface is protected by oxine copper and the inhibitor, the barrier layer 5 is smoothly etched back, and when the polishing is completed, the SiO ₂ insulating layer 2 and the copper surface in the wiring groove become substantially flat, which causes dishing and erosion. A product was obtained in which the temperature was suppressed.

Example 4 By the same method as in Example 1,
A sample prepared by depositing a copper film 6 having a film thickness T ₁ of about 1200 nm on a silicon substrate was prepared and polished in two steps. The maximum step D of the copper film 6 was 600 nm. The composite electropolishing of this sample was performed in two steps, a front stage and a rear stage. That is, in the first step, a composite electrolytic polishing was performed with mechanical polishing by using electrolytic polishing together with the copper surface as the anode, and in the latter step, a high voltage was applied between the cathode and the anode arranged facing the substrate. By making the local surface close to the cathode a pseudo anode by the bipolar phenomenon, electrolytic polishing was performed in a complex manner while increasing the solubility of copper.

In the first polishing step, the sample was held on the substrate holding part 16a of the polishing apparatus 10a shown in FIG. 4 with the copper plating surface facing downward, and the sample and the polishing tool 22 were rotated at 90 rpm in opposite directions. 250 on the polishing surface while rotating
The first polishing was performed by applying a polishing pressure of g / cm ² and using electrolytic polishing with the copper film 6 of the sample as an anode in the following polishing liquid.

The polishing liquid was purified water (85%) with phosphoric acid at 5.
Dissolve it in 0%, adjust the pH to 5.5 by adding aqueous ammonia, and propylene glycol monomethyl ether 10
%, 5.0% of colloidal silica having an average particle size of 40 nm,
0.15% 8-hydroxyquinoline, 0.1% propylene urea.
What was made to melt | dissolve 1% was used.

Here, as a current to be passed between the copper film 6 of the sample and the cathode plate 20, a current having a current density per surface area of copper on the substrate of 3 A / dm ² is passed for 10 × 10 ⁻³ seconds. However, a pulse current that similarly stops for 10 × 10 ⁻³ seconds was used. As a result of continuing the polishing for 60 seconds, the excess copper film 6 deposited on the substrate was polished from 1200 nm to about 300 nm, the maximum step difference was from 600 nm to 100 nm or less, and a high flattening effect was obtained.

Then, the polishing apparatus 10b shown in FIG. 6 was used to polish the latter stage of the sample under the same conditions as in Example 1. That is, as a polishing liquid, 1.0% ammonium oxalate and 0.5% (85%) phosphoric acid were dissolved in pure water,
Ammonia water was added to adjust the pH to 7.5, and 3.5% colloidal silica having an average particle size of 40 nm, 0.1% 8-hydroxyquinoline and 0.03% phenacetin were dissolved. .

The polishing apparatus 10b was operated, and immediately after the polishing of the copper surface was started, a voltage of 30 to 70 V was applied between the cathode rod 40 and the anode rod 42 to energize. At this time, the convex portion on the copper surface was selectively removed by generation and removal of oxine copper, and was also planarized simultaneously with the progress of polishing.
After applying the voltage for 40 seconds, the energization was stopped and the polishing was continued. When the polishing was completed after removing the barrier layer 5 made of the TaN / Ta film, the SiO ₂ insulating layer 2 and the copper surface in the wiring groove were substantially flat, and a good polished surface was obtained.

(Example 5) By the same method as in Example 1,
A sample prepared by depositing a copper film 6 having a film thickness T ₁ of about 1500 nm on a silicon substrate was prepared and polished in two steps. The maximum step D of the copper film 6 was 700 nm. In the first polishing step, the sample is held by the substrate holding part 16a of the polishing apparatus 10a shown in FIG.
While rotating the sample and the polishing tool 22 in opposite directions at a rotation speed of 90 rpm and applying a polishing pressure of 200 g / cm ² to the polishing surface, the following polishing liquid was continuously supplied to bring the polishing surface into the liquid. And electrolytic polishing was carried out while passing the following pulsed direct current through the surface to be polished as an anode.

As the polishing liquid, pure water (85%) phosphoric acid 10% and propylene glycol monomethyl ether 20 were used.
%, The pH was adjusted to 3.5 by adding aqueous ammonia, and further, 8-hydroxyquinoline 0.15% and propylene urea 0.2% were used. here,
The current density per surface area of copper on the substrate is 6 A / dm as the current passed between the copper film 6 of the sample and the cathode plate 20.
^A current of ² is applied for 10 × 10 ⁻³ seconds, and the same 10
A pulse current was used that stopped for × 10 ⁻³ seconds.

As a result of performing composite electropolishing for 65 seconds, the copper film 6 was changed from 1500 nm to 300 nm, and the polishing rate for the convex portions reached 1200 nm / min. The maximum step is 700
From nm to 100 nm or less, a high flattening effect was obtained. The polishing liquid that has flowed out of the polishing apparatus 10a is collected, filtered through a 100-micron, 5-micron, and 1-micron polypropylene cartridge filter connected in series to adjust the concentration of each component, and then returned to the polishing apparatus 10a again. When supplied and used for polishing, no trouble was found in the processing step and the polishing result of the substrate.

Next, the subsequent polishing was carried out under exactly the same conditions as in Example 2. That is, without using electrolysis, using a polishing liquid having the following composition containing 8-hydroxyquinoline,
According to the well-known CMP method, the polishing surface is held downward, and a pressure of 350 g / cm ² is applied between the polishing pad of the hard and soft double structures mounted on the opposing lower turntables, and the opposite directions are applied. Flattening polishing was performed while rotating at a speed of 70 rpm.

As a polishing liquid, ammonium oxalate 1.0
%, Hydrogen peroxide 10%, average particle size 40 nm colloidal silica 5.0%, nonionic surfactant 30 mg / L, 5
-Methylbenzotriazole having a composition of 0.05% and 8-hydroxyquinoline of 0.1% was used and continuously supplied from the polishing liquid supply unit 32 to the polishing surface. In the latter polishing step, a brittle film of oxine copper was formed on the surface of the copper film, and the projections were selectively removed and repeated repeatedly. Therefore, the polishing of the copper film proceeded further and the planarization was further promoted.

When the polishing proceeds, the excess copper film 6 deposited on the substrate is removed, and the barrier layer 5 made of the TaN film is exposed, the copper surface is protected by the anticorrosion film formed of oxine copper and the inhibitor, and the barrier layer is formed. For No. 5, the etch back was smoothly performed by the action of the organic acid and hydrogen peroxide. As a result, when polishing was completed, the SiO ₂ insulating layer 2 and the copper surface in the wiring groove were substantially flat, and a product in which dishing and erosion were minimized was obtained.

[0210]

As described above, according to the present invention,
When performing flattening polishing of a copper film with a step difference that is excessively deposited on the substrate, insoluble and fragile oxine copper is generated on the copper film, and the convex portion is selectively ground to achieve highly efficient flatness. Chemical processing is possible. Further, not only can the majority of the excessively deposited copper film be polished at a high speed by the composite electropolishing combined with electrolysis, but also the electrolytic action can eliminate the use of an oxidizing agent in the polishing liquid, and Stabilization and management are facilitated, and running costs can be reduced. Furthermore, in the first stage of the polishing step, it is possible to omit the use of polishing abrasive grains, whereby the used polishing liquid can be collected, filtered, and then adjusted in concentration to be used again, which reduces the amount of waste liquid. It can be expected and is favorable for environmental protection.

[Brief description of drawings]

FIG. 1 is a graph showing the relationship between the amount of copper reduction and the immersion time in a polishing liquid of the present invention.

FIG. 2 is a graph showing the relationship between the voltage between electrodes and the electrolysis time.

FIG. 3 is a graph showing the relationship between the electropolishing current and the amount of copper reduction, and the electrolysis time.

FIG. 4 is a sectional view showing an outline of a polishing apparatus according to an embodiment of the present invention.

5 is a diagram schematically showing a state of polishing by the polishing apparatus shown in FIG.

FIG. 6 is a sectional view showing the outline of a polishing apparatus according to another embodiment of the present invention.

FIG. 7 is a diagram schematically showing a state of polishing by the polishing apparatus shown in FIG.

8 is a plan layout view of a wiring forming device including the polishing device shown in FIGS. 4 and 6. FIG.

9 is a block diagram showing a flow of processing steps in the wiring forming apparatus shown in FIG.

10A to 10D are cross-sectional views showing an example of forming a wiring in the wiring forming apparatus shown in FIG.

FIG. 11 is a plan view showing a polishing apparatus according to still another embodiment of the present invention.

12 is a front view showing a substrate holding part used in the polishing apparatus shown in FIG.

13 is a plan layout view of a wiring forming apparatus including the polishing apparatus shown in FIG.

FIG. 14 is a sectional view showing an outline of a polishing apparatus according to still another embodiment of the present invention.

15 is an enlarged plan view showing a part of an electrode plate of the polishing apparatus shown in FIG.

FIG. 16 is a sectional view showing a part of the same in an enlarged manner.

FIG. 17 is a cross-sectional view of a sample used in Examples.

FIG. 18 is a cross-sectional view showing an example of forming a copper wiring by copper plating in the order of steps.

FIG. 19 is a cross-sectional view showing an entire electroplating apparatus as a copper plating apparatus during a plating process.

FIG. 20 is likewise a plating solution flow chart showing the state of the flow of the plating solution.

FIG. 21 is a sectional view showing the whole of the same when not plated (at the time of delivering the substrate).

FIG. 22 is a sectional view showing the whole of the same during maintenance.

FIG. 23 is a sectional view for explaining the relationship between the housing, the pressing ring and the substrate when the substrate is delivered.

FIG. 24 is likewise a partially enlarged view of FIG. 23.

FIG. 25 is also a diagram for explaining the flow of the plating solution during plating and during non-plating.

FIG. 26 is likewise an enlarged cross-sectional view of the centering mechanism.

FIG. 27 is a sectional view showing a power supply contact (probe) in the same manner.

FIG. 28 is a plan view showing another example of an electroplating apparatus as a copper plating apparatus.

FIG. 29 is likewise a cross-sectional view taken along the line AA of FIG. 28.

FIG. 30 is likewise a sectional view of the substrate holding part and the cathode part.

FIG. 31 is likewise a sectional view of an electrode arm portion.

FIG. 32 is likewise a plan view of the electrode arm portion excluding the housing.

FIG. 33 is also a schematic view showing an anode and a plating solution impregnated material.

FIG. 34 is a plan layout view showing the substrate processing apparatus.

FIG. 35 is a diagram showing the flow of airflow in the substrate processing apparatus shown in FIG. 34.

FIG. 36 is a diagram showing an air flow between areas of the substrate processing apparatus shown in FIG. 34.

37 is an external view showing an example in which the substrate processing apparatus shown in FIG. 34 is arranged in a clean room.

FIG. 38 is a plan layout view showing another example of the substrate processing apparatus.

FIG. 39 is a plan layout view showing still another example of the substrate processing apparatus.

FIG. 40 is a plan layout view showing still another example of the substrate processing apparatus.

FIG. 41 is a plan layout view showing still another example of the substrate processing apparatus.

FIG. 42 is a plan layout view showing still another example of the substrate processing apparatus.

FIG. 43 is a plan layout view showing still another example of the substrate processing apparatus.

FIG. 44 is a plan layout view showing still another example of the substrate processing apparatus.

FIG. 45 is a plan layout view showing still another example of the substrate processing apparatus.

FIG. 46 is a plan layout view showing still another example of the substrate processing apparatus.

47 is a flowchart showing the flow of each step in the substrate treatment apparatus shown in FIG. 46.

FIG. 48 is a schematic view showing a bevel / back surface cleaning unit.

FIG. 49 is a schematic view showing an example of an electroless plating apparatus.

FIG. 50 is a schematic view showing another example of the electroless plating apparatus.

FIG. 51 is a vertical sectional front view showing an example of an annealing unit.

52 is a plan sectional view of FIG. 51. FIG.

[Explanation of symbols]

2 insulating layers 4 wiring groove 5 barrier layers 6 Copper film 6a Oxin copper film 7 Seed layer 10a, 10b, 10c, 10d Polishing device 12 Polishing liquid 14 polishing tank 16a, 16b, 76 substrate holder 20 cathode plate 20a long groove 22 Polishing tool 26 electrical contacts 30,48 Rectifier 32 Polishing liquid supply unit 42 Anode rod 44 electrode plate 44a long groove 50 Polishing liquid regeneration unit 54 Load / unload section 58 Cleaning device 60 Annealing device 62 Washing / drying device 68 Conveyor 70 modules 72 swivel arm 74 electrode ring 78 Electrode ring attachment / detachment stage 140 cathode rod 156 Copper plating equipment

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) B24B 37/00 B24B 37/00 Z (72) Inventor Ryoichi Kimizuka 1-1-6 Yoshiyukizaka, Fujisawa City, Kanagawa Prefecture EBARA Ujilite Co., Ltd. F term (reference) 3C058 AA07 CA01 CB03 CB05 DA02 DA12 DA13 3C059 AA02 AB01 GC01

Claims (19)

[Claims] 1. A polishing liquid for forming a copper film on the surface and polishing the surface of a substrate having the copper embedded in fine recesses, which comprises a water-soluble inorganic acid or a salt thereof, or a water-soluble organic acid. Alternatively, a polishing liquid containing one or more kinds of salts thereof and one or more kinds of hydroxyquinolines. 2. The inorganic acid salt is a potassium salt or ammonium salt of an inorganic acid, and the organic acid salt is a potassium salt, an ammonium salt, an amine salt or a hydroxyamine salt of an organic acid. The polishing liquid according to claim 1. 3. The polishing liquid according to claim 1 or 2, wherein the hydroxyquinolines are 2-hydroxyquinoline, 4-hydroxyquinoline, 5-hydroxyquinoline or 8-hydroxyquinoline. 4. The water-soluble inorganic acid or a salt thereof,
Alternatively, the concentration of the water-soluble organic acid or its salt in the polishing liquid is 0.01 to 5.0 mol / L, and the conductivity of the polishing liquid is 0.5 to 100 mS / cm. The polishing liquid according to any one of claims 1 to 3. 5. The polishing liquid according to claim 1, wherein the concentration of the hydroxyquinolines in the polishing liquid is 0.001 to 1.0% by weight. 6. A benzotriazole or a derivative thereof as an agent for preventing corrosion and discoloration of copper, and 0.001 to 1 of at least one of benzimidazole and phenacetin.
The polishing liquid according to claim 1, wherein the polishing liquid is contained at a concentration of 0.5% by weight. 7. The polishing liquid according to claim 1, wherein the pH of the polishing liquid is in the range of 3-11. 8. The polishing liquid according to claim 1, which contains a surfactant in a concentration of 0.001 to 0.1% by weight. 9. When polishing a surface of a substrate in which a copper film is formed and the copper is embedded in fine recesses, a water-soluble inorganic acid or a salt thereof, or a water-soluble organic acid or a salt thereof is used. An oxine copper film formed on the surface of copper by electropolishing the surface of a substrate in a polishing liquid containing one or more types and one or more types of hydroxyquinolines, and reacting with the hydroxyquinolines added to the polishing liquid. A combined electrochemical / chemical / mechanical polishing method for a polishing surface containing copper, which is characterized in that both are simultaneously ground. 10. The polishing method according to claim 9, wherein one of direct current and pulsed current, or a superposed current of these currents is passed to perform electrolytic polishing. 11. The electrolytic polishing is performed by applying a current having a current density of 0.5 to 5.0 A / dm ² to the surface area of copper at the start of the electrolytic polishing.
The polishing method described in 0. 12. A large number of anodes and cathodes are alternately arranged in the polishing liquid so as to face the copper film formed on the surface of the substrate, and the cathodes are placed closer to the substrate than the anode, and the anodes and the cathodes are alternately arranged. 12. The oxine copper film is formed on the copper surface by applying a voltage between the electrodes, and by the positive polarity of the copper surface generated by the bipolar phenomenon at this time, to form the oxine copper film. Polishing method. 13. The interelectrode resistance between the cathode and the anode in the polishing liquid is 10 to 50 Ωcm, and the voltage applied between the cathode and the anode is 10 to 100.
13. The polishing method according to claim 12, wherein the polishing method is V. 14. A polishing apparatus for polishing a surface of a substrate in which a copper film is formed on the surface and the copper is embedded in fine recesses, wherein the water-soluble inorganic acid or its salt, or the water-soluble organic acid or Electrolytic polishing using a polishing liquid containing one or more salts thereof and one or more hydroxyquinolines, and an oxine copper film formed on the surface of copper by reacting with the hydroxyquinolines added to the polishing liquid. A polishing apparatus characterized in that the above-mentioned grinding is performed at the same time. 15. A substrate holding part for holding the substrate downward, one or more kinds of water-soluble inorganic acid or its salt, or a water-soluble organic acid or its salt, and one or more kinds of hydroxyquinoline. A polishing tank holding a polishing solution, a cathode plate placed by immersing it in the polishing solution held in the polishing tank, and immersed in the polishing solution held in the polishing tank facing the cathode plate A polishing apparatus comprising: a polishing tool that is arranged, and a relative movement mechanism that relatively moves the substrate held by the substrate holding unit and the polishing tool. 16. The polishing apparatus according to claim 15, wherein the surface of the cathode plate is formed with a large number of grooves continuously extending over the entire length in the surface. 17. A substrate holding part for holding a substrate, a polishing liquid containing one or more kinds of water-soluble inorganic acids or salts thereof, or water-soluble organic acids or salts thereof, and one or more kinds of hydroxyquinolines. A polishing tank for holding, an electrode plate in which a large number of anodes and cathodes are alternately arranged by bringing the cathodes closer to the substrate held by the substrate holding unit than the anodes and alternately arranged, and between the anodes and the cathodes A power source for applying a voltage, a polishing tool that is arranged so as to be opposed to the electrode plate and immersed in a polishing liquid held in the polishing tank, and a substrate held by the substrate holding section and the polishing tool are relatively moved. A polishing apparatus having a relative movement mechanism. 18. The polishing apparatus according to claim 17, wherein the surface of the electrode plate is provided with a large number of grooves extending over the entire length in the surface. 19. The polishing apparatus according to claim 15 and the polishing apparatus according to claim 17 are arranged in a partitioned room in the same module, and the movement of the substrate between the polishing apparatuses is carried out in the module. A polishing device characterized in that it is carried out by a swiveling arm arranged.