JP2005325396A - Plating device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a plating device capable of effectively suppressing the defect of wiring caused by plating. <P>SOLUTION: The plating device 10 is at least provided with a plating treatment chamber 11 for performing plating to a substrate, an etching-washing-drying chamber 12 for performing etching, washing and drying to the substrate at the inside, and is further provided with a substrate carrying mechanism 13 for performing the carrying of the substrate between the respective chambers and between the respective chambers and a substrate load/unload part, wherein as volatile substance removing mechanisms capable of removing volatile substance comprised in an air flow flowing into the plating device 10 and/or circulating in the plating device, a particulate removing filter 17 composed of a HEPA (High-efficiency Particulate Air) filter or an ULPA (Ultra Low Penetration Air) filter and a chemical filter 18 are arranged. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a plating apparatus for forming a metal plating film for LSI (Large Scale Integrated Circuit) wiring on a substrate such as a semiconductor wafer, and more particularly to a plating apparatus effective for suppressing wiring defects caused by plating. .

  In recent years, LSI wiring materials have moved from aluminum to copper, and a copper plating method has been adopted as a wiring forming method. FIG. 1 is a diagram showing a schematic configuration of this type of conventional plating apparatus, in which FIG. 1 (a) is a plan view and FIG. 1 (b) is a side view. The plating apparatus 10 includes a plurality of (three in the figure) plating processing chambers 11 for forming a plating film on the substrate, and a plurality of (three in the figure) etching / cleaning for etching, cleaning and drying. A substrate storage in which a drying chamber 12, a substrate transfer mechanism 13 for transferring a substrate such as a robot, and a chemical solution management unit 14 are arranged, and a plurality (two in the figure) of substrate holders 15 are placed near the outside of the apparatus. A container mounting table 16 is arranged.

  The substrate transport mechanism 13 sequentially takes out a substrate (for example, a semiconductor wafer) from one substrate container 15 and sequentially carries it into each plating processing chamber 11 to perform plating processing. The substrate after the plating film is formed is sent to each plating processing chamber 11. Are sequentially taken out, carried into each etching / cleaning / drying processing chamber 12, subjected to etching / cleaning / drying processing in each etching / cleaning / drying processing chamber 12, and the dried substrate is stored in the other substrate container 15.

  In the plating apparatus having the above-described configuration, the fine particle removal filter 17 of the HEPA filter (High-Efficiency Particulate Air Filter) or the ULPA filter (Ultra Low Penetration Air Filter) is disposed in the upper part of the apparatus. A part of the air inside the plating apparatus is discharged to the outside through the duct 20 as the exhaust 101, the other is circulated through the particulate removal filter 17 as the circulating air 102, and further air is taken in from the outside through the particulate removal filter 17 as the intake air 103. . The HEPA filter is a filter capable of removing 99.97% of 0.3 micron particles, and the ULPA filter is a high performance filter capable of removing 99.9995% of 0.15 micron particles. Note that the air in each plating treatment chamber 11 is exhausted to the outside as exhaust 104 through the dedicated exhaust duct 21. Further, the air of the chemical solution management unit 14 is also discharged to the outside as the exhaust 105 through the exhaust duct 22.

  In a conventional copper plating process, a copper seed layer formed by sputtering, CVD, ALD, electroless plating or the like is used as a seed layer. With the progress of miniaturization of the wiring size, the thickness of the copper sheet layer is decreasing year by year. The thickness of the copper seed layer when manufacturing a 65 nm generation device is around 600 angstroms in the substrate field. When this is the 45 nm generation, it is expected to be 500 angstroms or less.

In the copper wiring forming process, a method of forming a copper wiring by such a copper sulfate plating method is effective on such a thin copper seed layer. Thereafter, the copper crystals are grown and stabilized by heat treatment, and the excess copper film is removed by CMP (Chemical Mechanical Polishing). In the manufacture of LSI, it is common to make the copper wiring formed in this way into 10 or more layers.
JP 2002-129349 A

  As wiring miniaturization has progressed, defects in copper wiring have become a problem. A defect is a state in which a part of the copper wiring is missing, a state in which abnormal plating deposition has occurred on a part of the copper wiring, or a void is formed by heat treatment after plating. A generic term for easy singularities. Although these may be caused by defects in processes other than plating, defects due to plating tend to increase with the progress of miniaturization, which significantly hinders improvement in product yield.

  As one cause of defect occurrence, volatile substances are also considered to be adsorbed on the substrate surface such as organic solvents such as benzene, toluene, xylene and amine, alkali agents such as ammonia, and lower organic acids.

  In addition, LSI manufacturing is performed in an extremely clarified clean room, but in recent years, the cleanliness of the entire clean room has become worse than 10 years ago due to advances in local clean technology called hoop, sumif, and E-cube. Yes. This is due to the huge amount of investment in clean room facilities. It is thought that there is such a change in specifications behind the increase in defects.

  This invention is made | formed in view of the above-mentioned point, and it aims at providing the plating apparatus which can suppress the wiring defect resulting from plating effectively.

  In order to solve the above problems, the invention described in claim 1 includes a plating treatment chamber for plating at least a substrate inside, a substrate cleaning / drying chamber for cleaning and drying the substrate, and between these chambers and In a plating apparatus having a substrate transfer mechanism for transferring a substrate between each chamber and the substrate loading / unloading section, volatile substances contained in the airflow flowing into and / or circulating in the plating apparatus are removed. Featuring possible volatile removal mechanisms.

  According to a second aspect of the present invention, in the plating apparatus according to the first aspect, the volatile substance removing mechanism is a chemical filter.

  According to a third aspect of the present invention, in the plating apparatus according to the second aspect, the installation location of the chemical filter is an upper part of the plating apparatus.

  The invention according to claim 4 is the plating apparatus according to claim 2 or 3, wherein the chemical filter is at least one of activated carbon, zeolite, polymer film, polymer fiber, nonwoven fabric, and a member obtained by chemically modifying these. Or one or more of them.

  According to a fifth aspect of the present invention, in the plating apparatus according to the first aspect, the volatile substance removing mechanism has both a chemical removing function and a fine particle removing function.

  According to a sixth aspect of the present invention, in the plating apparatus according to the first aspect, the volatile substance removing mechanism is a scrubber.

  A seventh aspect of the invention is characterized in that, in the plating apparatus of the first aspect, the volatile substance removing mechanism is a thermal decomposition mechanism or a catalyst combined thermal decomposition mechanism.

  The invention according to claim 8 includes a plating processing chamber for plating at least a substrate inside, a substrate cleaning / drying chamber for cleaning and drying the substrate, and between these chambers and each chamber and substrate loading / unloading. In a plating apparatus having a substrate transfer mechanism for transferring a substrate between load units, the internal pressure of the apparatus is set lower than the outside of the apparatus, and the internal pressure of each chamber is set lower than the internal pressure of the apparatus.

  According to the first aspect of the present invention, since a volatile substance removing mechanism capable of removing volatile substances contained in the airflow flowing into and / or circulating in the plating apparatus is provided, volatilization in the airflow is eliminated. Since the volatile substances are removed, these volatile substances are not adsorbed on the substrate surface in the apparatus, and the occurrence of defects caused by plating can be suppressed. As a result, defects caused by plating can be reduced with a low investment, which can contribute to an improvement in yield of LSI products and low-cost production.

  According to the second aspect of the present invention, since the chemical filter is also used as the volatile substance removing mechanism, the volatile substance is efficiently captured and removed by the chemical filter, so that the occurrence of defects can be suppressed.

  According to the third aspect of the present invention, since the chemical filter is installed in the upper part of the plating apparatus, the air from which the volatile substances have been removed by the chemical filter flows into the apparatus as a descending airflow, The downdraft required in (1) is preferably generated.

  According to the description of claim 4, the chemical filter is composed of at least one of activated carbon, zeolite, polymer membrane, polymer fiber, nonwoven fabric, and a member obtained by chemically modifying these, or two or more thereof. Volatile substances such as basic gases such as ammonia and trimethylamine, acidic gases such as Sox, Nox, and chlorine, and organic gases such as xylene, toluene, benzene, and siloxane are efficiently captured and removed, particularly inducing plating defects. Generation of defects can be suppressed because toluene, xylene and the like which are considered to be promoted are efficiently captured and removed.

  According to the fifth aspect of the present invention, since the volatile substance removing mechanism has both the chemical removing function and the fine particle removing function, not only the volatile substance in the airflow but also the fine particles can be removed, thereby further suppressing the occurrence of defects. it can.

  According to the sixth aspect, since the volatile substance removing mechanism is a scrubber, the volatile substance in the air is adsorbed by the adsorbing liquid in the scrubber by passing the air introduced into the plating apparatus through the scrubber. Since air without volatile substances is introduced into the plating apparatus, the occurrence of defects can be suppressed.

  According to the seventh aspect of the present invention, since the volatile substance removal mechanism is a thermal decomposition mechanism or a catalyst combined type thermal decomposition mechanism, the heat decomposition mechanism or the catalyst combined type thermal decomposition mechanism is introduced into the air introduced into the plating apparatus. By passing through the inside, the volatile substance is thermally decomposed, and air having no volatile substance is introduced into the plating apparatus, so that the occurrence of defects can be suppressed.

  According to the eighth aspect of the present invention, since the internal pressure of the apparatus is set lower than the outside of the apparatus and the internal pressure of each chamber is set lower than the internal pressure of the apparatus, air contaminated with a chemical mist handled in the plating apparatus leaks to the outside. Even if the plating apparatus is installed in a clean room, the inside of the clean room is not contaminated with chemical mist or the like handled in the plating apparatus.

  Embodiments of the present invention will be described below with reference to the drawings.

  FIG. 2 is a diagram showing a schematic configuration of a plating apparatus according to the present invention. 2, the same reference numerals as those in FIG. 1 denote the same or corresponding parts. The same applies to other drawings. In FIG. 2, reference numeral 19 denotes a filter in which a fine particle removal filter 17 made of a HEPA filter or a ULPA filter and a chemical filter 18 are combined. The filter 19 is provided in the upper part in the apparatus. The filter 17 is composed of the above-mentioned HEPA filter or ULPA filter, and has a fine particle removal function, and the chemical filter 18 has a volatile substance removal function. Therefore, the filter 19 combining these has a fine particle removal function and a volatile substance removal function. It is a filter with both.

  In the plating apparatus 10 configured as described above, a part of the air in the apparatus is discharged outside the apparatus as the exhaust 101, the other is circulated through the filter 19 as the circulating air 102, and the air from the outside is passed through the filter 19 as the intake air 103. It is incorporated inside. Further, the air in each plating treatment chamber 11 is discharged out of the apparatus as exhaust 104 through the dedicated exhaust duct 21. Further, an air flow 106 flows into the chemical solution management unit 14 from the region where the plating treatment chamber 11 and the etching / cleaning / drying treatment chamber 12 are arranged, and the air in the chemical solution management unit 14 is exhausted through the exhaust duct 22. 105 is discharged.

  As the chemical filter 18, activated carbon, drug-added activated carbon, porous material, plastic fiber / membrane / nonwoven fabric with various functional groups, and the like can be used. Volatile substances that can be removed by the chemical filter 18 are basic gases such as ammonia and trimethylamine, acidic gases such as Sox, Nox, and chlorine, and organic gases such as xylene, toluene, benzene, and siloxane. Not. Among these, it is becoming clear that at least organic gases such as toluene and xylene induce and promote plating defects.

  These organic volatile substances are adsorbed on the substrate surface (the Cu seed layer surface or the barrier metal layer surface). Since these organic volatile substances are organic substances that do not mix with the plating solution, the plating solution is repelled and plating defects occur. These organic volatile substances have a low removal rate with the particulate removal filter 17 formed of a HEPA filter or a ULPA filter, but a removal rate with a chemical filter 18 such as activated carbon is very high. In this example, by installing the chemical filter 18, data was obtained in which the plating missing density decreased from 5.5 locations / substrate to 0.1 locations / substrate or less.

  FIG. 3 is a diagram showing a schematic configuration of a plating apparatus according to the present invention. The plating apparatus of FIG. 3 differs from the plating apparatus of FIG. 2 in that a fine particle removal filter 17 and a chemical filter 18 are provided on the outer upper part of the plating apparatus 10 and the circulating air 102 is only a fine particle removal filter 17 composed of a HEPA filter or a ULPA filter. It is the point which introduces in a device through. Further, the intake air 103 from the outside is taken into the apparatus through a filter 19 in which the chemical filter 18 and the particulate removal filter 17 are combined, as in FIG.

  FIG. 4 is a diagram showing a schematic configuration of a plating apparatus according to the present invention. As shown in the figure, the present plating apparatus 10 is provided with a filter 19 in which a chemical filter 18 and a particulate removal filter 17 composed of a HEPA filter or a ULPA filter are combined at the upper part on the outer side of the apparatus. A chemical filter 18 and a particulate removal filter 17 are combined into a plating apparatus 10 through a filter 19.

  Although the installation place of the chemical filter 18 is not limited, it is usually provided at the upper part inside the apparatus or the upper part outside the apparatus as shown in FIGS. This is because the downflow of clean air is required in the plating apparatus 10.

  FIG. 5 is a diagram showing a schematic configuration of a plating apparatus according to the present invention. Here, a scrubber 30 is provided as a device for removing volatile organic substances, an intake air 103 from the outside is provided in the upper part of the plating device 10 through the scrubber 30, and taken in through a particulate removal filter 17 made of a HEPA filter or a ULPA filter. ing. The scrubber 30 includes a pump 31, a pipe 32, and a sprinkling pipe 33. The pump 31 supplies the absorbing liquid 107 staying in the lower tank to the sprinkling pipe 33 through the pipe 32, and the absorbing liquid 107 flows downward from the sprinkling pipe 33. Watered. The intake air 103 attracted by the fan 34 rises through the water spray, and during that time, volatile substances contained in the intake air 103 come into contact with the absorbing liquid 107 and are absorbed and removed. The volatile substance is removed, and the intake air 103 is supplied into the plating apparatus 10 through the particulate removal filter 17. Normally, water is used as the absorbing liquid 107 used in the scrubber 30, but it is not limited to water as long as it is a solvent that can remove the organic substance to be removed.

  FIG. 6 is a diagram showing a schematic configuration of a plating apparatus according to the present invention. In this plating apparatus, as a device for removing volatile organic substances, a pyrolysis furnace 40 comprising a heating furnace or a catalyst combined heating furnace is provided, and an intake air 103 is fed into the pyrolysis furnace 40 by a fan 41 and is introduced into the intake air 103. The contained volatile organic substance is thermally decomposed and the volatile organic substance is thermally decomposed, and the particulate filter 17 comprising a chemical filter 18 and a HEPA filter or ULPA filter provided in the upper part of the plating apparatus 10 with the intake air 103. It is taken in through the filter 19 combined.

  When a catalyst combined heating furnace is used for the pyrolysis furnace 40, palladium, platinum, zirconium or the like is frequently used as the catalyst, but is not limited thereto. The heating temperature of the thermal decomposition furnace 40 is appropriately determined according to the decomposition characteristics of the volatile organic substance to be removed.

FIG. 7 is a diagram showing the pressure inside and outside the plating apparatus according to the present invention. The pressure in the clean room in which the plating apparatus is installed is P0, the pressure in the apparatus area where the plating process chamber 11 and the etching / cleaning / drying process chamber 12 are arranged is P1, and the pressure in the plating process chamber 11 is P2. If
P0>P1> P2
And

  An area where the plating chamber 11 and the etching / cleaning / drying chamber 12 are arranged in the plating apparatus 10 is an area where hydrogen chloride or sulfuric acid mist generated from the plating solution, or an alkaline agent (TMAH) contained in the electroless plating solution, Since a reducing agent (formalin) may be included, the pressure inside the apparatus is usually kept lower than the outside (in the clean room). However, since cleanliness in recent clean rooms is about class 1000, it is essential to install a particulate removal filter 17 composed of a HEPA filter or ULPA filter in the intake air 103 from the outside (clean room). In the plating processing chamber 11 and the etching / cleaning / drying processing chamber 12, since the chemical solution is used, the inside of the chamber is forcibly evacuated, so the pressure is kept the lowest in the apparatus. The pressure relationship inside and outside the plating apparatus 10 is applied to the plating apparatus 10 shown in FIGS.

  According to the plating apparatus according to the present invention, since the volatile substance that is one of the causes of plating defects is prevented from entering the apparatus, the volatile substance is not adsorbed on the surface of the seed layer of the substrate. Therefore, it is possible to significantly reduce defects caused by plating at a low cost. Further, the present invention is not limited to a plating apparatus, but is considered to be effective in other film forming, polishing, cleaning apparatuses, and etching apparatuses.

  Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and various modifications can be made within the scope of the technical idea described in the claims and the specification and drawings. Is possible. For example, the etching / cleaning / drying processing chamber 12 may be a cleaning / drying processing chamber for performing cleaning and drying. A substrate loading / unloading unit may also be provided in the apparatus.

It is a figure which shows schematic structure of the conventional plating apparatus. It is a figure which shows schematic structure of the plating apparatus which concerns on this invention. Example 1 It is a figure which shows schematic structure of the plating apparatus which concerns on this invention. (Example 2) It is a figure which shows schematic structure of the plating apparatus which concerns on this invention. Example 3 It is a figure which shows schematic structure of the plating apparatus which concerns on this invention. (Example 4) It is a figure which shows schematic structure of the plating apparatus which concerns on this invention. (Example 5) It is a figure which shows schematic structure of the plating apparatus which concerns on this invention. (Example 6)

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Plating apparatus 11 Plating processing chamber 12 Etching / cleaning / drying processing chamber 13 Substrate transport mechanism 14 Chemical solution management unit 15 Substrate container 16 Substrate container mounting table 17 Fine particle removal filter 18 Chemical filter 19 Filter 20 Duct 21 Dedicated exhaust duct 22 Exhaust Duct 30 Scrubber 31 Pump 32 Piping 33 Sprinkling pipe 34 Fan 40 Thermal decomposition furnace 41 Fan

Claims (8)

It has at least a plating chamber for plating the substrate, a substrate cleaning / drying chamber for cleaning and drying the substrate, and transporting the substrate between these chambers and between each chamber and the substrate loading / unloading unit. In a plating apparatus equipped with a substrate transport mechanism,
A plating apparatus comprising a volatile substance removing mechanism capable of removing volatile substances contained in an airflow flowing into and / or circulating in the plating apparatus. The plating apparatus according to claim 1,
The plating apparatus, wherein the volatile substance removing mechanism is a chemical filter. The plating apparatus according to claim 2,
A plating apparatus, wherein the chemical filter is installed at an upper part of the plating apparatus. In the plating apparatus according to claim 2 or 3,
The chemical filter is composed of at least one of activated carbon, zeolite, polymer film, polymer fiber, non-woven fabric, and a member obtained by chemically modifying these, or a plating apparatus. The plating apparatus according to claim 1,
A plating apparatus, wherein the volatile substance removing mechanism has both a chemical removing function and a fine particle removing function. The plating apparatus according to claim 1,
A plating apparatus, wherein the volatile substance removing mechanism is a scrubber. The plating apparatus according to claim 1,
The plating apparatus, wherein the volatile substance removing mechanism is a heat decomposition mechanism or a catalyst combined heat decomposition mechanism. It has at least a plating chamber for plating the substrate, a substrate cleaning / drying chamber for cleaning and drying the substrate, and transporting the substrate between these chambers and between each chamber and the substrate loading / unloading unit. In a plating apparatus equipped with a substrate transport mechanism,
The plating apparatus characterized in that the internal pressure of the apparatus is set lower than the outside of the apparatus and each chamber internal pressure is set lower than the internal pressure of the apparatus.

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