JP2018020282A - Substrate processing method, program, computer storage medium, and substrate processing system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To easily form a film having a desired shape corresponding to a shape of a base film on the base film even when the base film of the substrate is microfabricated.SOLUTION: A base film of a wafer W includes a metal film 401 and an insulating film 402. A substrate processing method forms a pattern of a shape corresponding to a shape of the metal film 401 on the metal film 401 or forms a pattern of a shape corresponding to a shape of the insulating film 402 on the insulating film 402, and includes surface modification process of surface-modifying the insulating film 402 by a surface modification fluid; an application process of applying a block copolymer 403 containing a first polymer and a second polymer on the base film; a phase separation process of heating the wafer W and phase-separating the block copolymer 403 in a shape corresponding to the shape of the metal film 401 and the shape of the insulating film 402; and a removing process of selectively removing either one of the first polymer or the second polymer of the phase-separated block copolymer.SELECTED DRAWING: Figure 6

Description

  The present invention relates to a substrate processing method, a program, a computer storage medium, and a substrate processing system for forming a pattern corresponding to the shape of the base film on the base film of the substrate.

  In a semiconductor device manufacturing process, a damascene method using copper as a wiring material is known as a technique for forming a wiring having a shape corresponding to a metal film included in a base film of a substrate (patent) Reference 1 and 2).

  Also, in the semiconductor device manufacturing process, a resist coating process for coating a resist solution on a substrate to form a resist film, an exposure process for exposing a predetermined pattern on the resist film, and a development process for developing the exposed resist film A photolithography technique is used in which a predetermined resist pattern is formed on the substrate by sequentially performing the above and the like.

  This photolithography technique is also used in the above-described damascene method, and a resist pattern is formed on the base film of the substrate. Then, using this resist pattern as a mask, the interlayer insulating film is etched to form a groove pattern. Thereafter, after removing the resist pattern, a copper film is deposited, and then an unnecessary copper film is removed by chemical mechanical polishing (CMP). As a result, the copper film formed in the groove pattern constitutes a wiring.

Japanese Patent Laid-Open No. 11-220025 JP 2000-21882 A

  Incidentally, in recent years, in order to further increase the integration of semiconductor devices, miniaturization of wiring, that is, the above-described groove pattern has been demanded. For this reason, miniaturization of the resist pattern is required. As a method for refining a resist pattern, multi-patterning such as so-called double patterning in which exposure processing and development processing are performed a plurality of times is known.

However, miniaturization of the wiring means that the underlying metal film is also miniaturized, and it is technically very difficult to form the wiring on the miniaturized metal film by multi-patterning. This is because it is very difficult to form a resist pattern in alignment with the miniaturized metal film.
Multi-patterning is costly due to the large number of processes.

  Such a problem is not limited to the case where a wiring having a shape corresponding to the metal film is formed on the metal film included in the base film of the substrate, but also to the metal film on the metal film included in the base film of the substrate. It exists also when forming a desired film other than the metal of the shape. It also exists when a desired film having a shape corresponding to the film is formed on a film other than the metal film included in the base film of the substrate.

  The present invention has been made in view of such points, and even when the base film of the substrate is miniaturized, a desired film having a shape corresponding to the shape of the base film can be easily formed on the base film. It aims to be able to form.

  To achieve the above object, according to the present invention, a base film of a substrate includes a first film and a second film, and a pattern having a shape corresponding to the shape of the first film is formed on the first film. A substrate processing method for forming or forming a pattern having a shape corresponding to the shape of the second film on the second film, wherein the first film and the base film are formed by a surface modifying fluid. A surface modification step of modifying one of the second films, a coating step of applying a block copolymer containing a first polymer and a second polymer to the base film, and heating the substrate A phase separation step of phase-separating the block copolymer into a shape corresponding to the shape of the first film and the shape of the second film, and the first of the block copolymer subjected to phase separation. Removal process for selectively removing either one of the polymer and the second polymer When, the substrate processing forming method comprising.

  It is preferable to include a film forming step of forming a desired film so as to fill the portion where either one of the first polymer and the second polymer is selectively removed.

  The block copolymer is re-coated on the phase-separated block copolymer, and the re-coated block copolymer has a shape corresponding to the shapes of the first polymer and the second polymer that have already been phase-separated. It is preferable to include a laminating step for phase separation.

  The laminating step is preferably performed a plurality of times.

  In the removal step, the block copolymer phase-separated in the phase separation step and the block copolymer phase-separated in the lamination step are combined with either the first polymer or the second polymer. It is preferable to remove selectively.

  It is preferable to include a film batch forming step of forming a desired film so as to fill a portion where either one of the first polymer and the second polymer is selectively removed collectively.

  The first film may be a metal film, and the second film may be a semiconductor film or an insulating film.

  The metal film can be formed of cobalt, nickel, titanium, titanium nitride, tungsten, tungsten nitride, copper, or ruthenium.

  The semiconductor film or the insulating film is, for example, a silicon semiconductor film or an insulating film containing silicon.

  As the surface modification fluid, a gas or liquid of a compound having a Si—N bond can be used.

  The compound having a Si—N bond is, for example, trimethylsilyldimethylamine or diphenylmethyldimethylaminosilane.

  The surface modification fluid may be a gas or liquid of a compound having a functional group that reacts with the metal film.

  According to another aspect of the present invention, there is provided a program that operates on a computer of a control unit that controls the substrate processing system so that the substrate processing method is executed by the substrate processing system.

  According to another aspect of the present invention, a readable computer storage medium storing the program is provided.

  According to yet another aspect of the present invention, the base film of the substrate includes a first film and a second film, and a pattern having a shape corresponding to the shape of the first film is formed on the first film, Alternatively, a substrate processing system for forming a pattern having a shape corresponding to the shape of the second film on the second film, wherein the first film and the second film of the base film are formed by a surface modification fluid. A surface modification device for surface modification of any one of the film, a coating device for applying a block copolymer containing a first polymer and a second polymer to the base film, and heating the substrate, A phase separation device for phase-separating a block copolymer into a shape corresponding to the shape of the first membrane and the shape of the second membrane; the first polymer of the block copolymer phase-separated; A polymer that selectively removes one of the second polymers It is characterized in that it comprises removed by the device.

  According to the present invention, even when the base film of the substrate is miniaturized, a desired film having a shape corresponding to the shape of the base film can be easily formed on the base film.

It is explanatory drawing of the plane which shows the outline of a structure of the substrate processing system 1 which enforces the substrate processing method which concerns on the 1st Embodiment of this invention. It is explanatory drawing of the plane which shows the outline of a structure of a pattern formation apparatus. It is explanatory drawing of the front which shows the outline of a structure of a pattern formation apparatus. It is explanatory drawing of the back surface which shows the outline of a structure of a pattern apparatus. It is a flowchart explaining wafer processing. It is a figure which shows the mode of the wafer at the time of wafer processing. It is a figure which shows the mode of the wafer at the time of wafer processing. It is a figure which shows the example of a surface modification fluid (it is also called a surface modifier). It is a figure which shows the mode of the wafer at the time of the wafer process which concerns on the 5th Embodiment of this invention.

  Embodiments of the present invention will be described below with reference to the accompanying drawings. The present invention is not limited to the embodiments described below. In the present specification and drawings, elements having substantially the same functional configuration are denoted by the same reference numerals, and redundant description is omitted.

<First Embodiment>
FIG. 1 is an explanatory plan view showing an outline of a configuration of a substrate processing system 1 for performing a substrate processing method according to a first embodiment of the present invention.

  The substrate processing system 1 includes a pattern forming device 2, a metal film forming device 3, and an insulating film forming device 4, and each device 2, 3, 4 is connected to the control unit 300.

  FIG. 2 is an explanatory diagram of a plan view of the pattern forming apparatus 2, and FIGS. 3 and 4 are a front view and a rear view schematically showing an outline of the internal configuration of the pattern forming apparatus 2.

The pattern forming apparatus 2 forms a predetermined pattern on a substrate by photolithography processing or the like on a wafer as a substrate. As shown in FIG. 2, the pattern forming apparatus 2 includes a cassette station 10 in which a cassette C containing a plurality of wafers W is loaded and unloaded, and a processing station including a plurality of various processing apparatuses that perform predetermined processing on the wafers W. 11 and an interface station 13 for transferring the wafer W between the exposure station 12 adjacent to the processing station 11 are integrally connected.
A base film is formed in advance on the wafer W to be processed by the pattern forming apparatus 2. The base film includes a first film having a predetermined shape and a second film having another predetermined shape. The first film is, for example, a metal film, and the second film is, for example, an insulating film.

  The cassette station 10 is provided with a cassette mounting table 20. The cassette mounting table 20 is provided with a plurality of cassette mounting plates 21 on which the cassette C is mounted when the cassette C is carried into and out of the substrate processing system 1.

  As shown in FIG. 2, the cassette station 10 is provided with a wafer transfer device 23 that is movable on a transfer path 22 that extends in the X direction. The wafer transfer device 23 is also movable in the vertical direction and the vertical axis direction (θ direction), and includes a cassette C on each cassette mounting plate 21 and a delivery device for a third block G3 of the processing station 11 described later. The wafer W can be transferred between the two.

  The processing station 11 is provided with a plurality of, for example, four blocks G1, G2, G3, and G4 having various devices. For example, the first block G1 is provided on the front side of the processing station 11 (X direction negative direction side in FIG. 2), and the second side is provided on the back side of the processing station 11 (X direction positive direction side in FIG. 2). Block G2 is provided. Further, a third block G3 is provided on the cassette station 10 side (Y direction negative direction side in FIG. 2) of the processing station 11, and the interface station 13 side (Y direction positive direction side in FIG. 2) of the processing station 11 is provided. Is provided with a fourth block G4.

  For example, in the first block G1, as shown in FIG. 3, a plurality of liquid processing apparatuses, for example, an organic solvent supplying apparatus 30 as a polymer removing apparatus for supplying an organic solvent onto the wafer W, Block copolymer coating devices 31 for coating the coalesced are stacked in order from the bottom.

  For example, three organic solvent supply devices 30 and three block copolymer coating devices 31 are arranged in the horizontal direction. The number and arrangement of these liquid processing apparatuses can be arbitrarily selected.

  In these liquid processing apparatuses, for example, spin coating for applying a predetermined coating liquid onto the wafer W is performed. In spin coating, for example, a coating liquid is discharged onto the wafer W from a coating nozzle, and the wafer W is rotated to diffuse the coating liquid to the surface of the wafer W.

  Note that the block copolymer applied on the wafer W by the block copolymer coating device 31 is a first polymer in which the first monomer and the second monomer are linearly polymerized (the weight of the first monomer). A polymer (copolymer) having a polymer) and a second polymer (polymer of the second monomer). As the first polymer, a hydrophilic polymer having hydrophilicity (polarity) is used, and as the second polymer, a hydrophobic polymer having hydrophobicity (nonpolarity) is used. In the present embodiment, the ratio of the molecular weight of the hydrophilic polymer in the block copolymer is about 40% to 60%, and the ratio of the molecular weight of the hydrophobic polymer in the block copolymer is about 60% to 40%. Further, for example, polymethyl methacrylate (PMMA) is used as the hydrophilic polymer, and polystyrene (PS) is used as the hydrophobic polymer. Hereinafter, a block copolymer of polystyrene (PS) and polymethyl methacrylate (PMMA) is referred to as PS-b-PMMA.

  The block copolymer coating device 31 applies PS-b-PMMA in solution with a solvent. The solvent is not particularly limited as long as it is highly compatible with PS and PMMA constituting PS-b-PMMA, and examples thereof include toluene and propylene glycol monomethyl ether acetate (PGMEA).

  For example, in the second block G2, as shown in FIG. 4, a heat treatment apparatus 40 that performs heat treatment of the wafer W, a surface modification apparatus 41 that selectively surface-modifies the base film of the wafer W with a surface modification fluid, A polymer separating device 42 for phase-separating the block copolymer applied on the wafer W by the coalescing device 31 into a hydrophilic polymer and a hydrophobic polymer, and an ultraviolet irradiation device 43 for irradiating the wafer W with ultraviolet rays are in the vertical direction. They are arranged side by side in the horizontal direction. The heat treatment apparatus 40 includes a hot plate for placing and heating the wafer W and a cooling plate for placing and cooling the wafer W, and can perform both heat treatment and cooling treatment. The polymer separation device 42 is also a device that performs heat treatment on the wafer W, and the configuration thereof is the same as that of the heat treatment device 40. The ultraviolet irradiation device 43 includes a mounting table on which the wafer W is mounted, and an ultraviolet irradiation unit that irradiates the wafer W on the mounting table with, for example, ultraviolet light having a wavelength of 172 nm. The number and arrangement of the heat treatment apparatus 40, the surface modification apparatus 41, the polymer separation apparatus 42, and the ultraviolet irradiation apparatus 43 can be arbitrarily selected.

  For example, in the third block G3, a plurality of delivery devices 50, 51, 52, 53, 54, 55, and 56 are provided in order from the bottom. The fourth block G4 is provided with a plurality of delivery devices 60, 61, 62 in order from the bottom.

  As shown in FIG. 2, a wafer transfer region D is formed in a region surrounded by the first block G1 to the fourth block G4. In the wafer transfer region D, for example, a plurality of wafer transfer devices 70 having transfer arms that are movable in the Y direction, the X direction, the θ direction, and the vertical direction are arranged. The wafer transfer device 70 moves in the wafer transfer area D and transfers the wafer W to a predetermined device in the surrounding first block G1, second block G2, third block G3, and fourth block G4. it can.

  Further, in the wafer transfer region D, a shuttle transfer device 80 that transfers the wafer W linearly between the third block G3 and the fourth block G4 is provided.

  The shuttle transport device 80 is movable linearly in the Y direction, for example. The shuttle transfer device 80 moves in the Y direction while supporting the wafer W, and can transfer the wafer W between the transfer device 52 of the third block G3 and the transfer device 62 of the fourth block G4.

  As shown in FIG. 2, a wafer transfer device 90 is provided next to the third block G3 on the positive side in the X direction. The wafer transfer device 90 has a transfer arm that is movable in the X direction, the θ direction, and the vertical direction, for example. The wafer transfer device 90 moves up and down while supporting the wafer W, and can transfer the wafer W to each delivery device in the third block G3.

  The interface station 13 is provided with a wafer transfer device 91 and a delivery device 92. The wafer transfer device 91 has a transfer arm that is movable in the Y direction, the θ direction, and the vertical direction, for example. For example, the wafer transfer device 91 can transfer the wafer W between each transfer device, the transfer device 92, and the exposure device 12 in the fourth block G4 by supporting the wafer W on the transfer arm.

Returning to the description of FIG.
The metal film forming apparatus 3 forms a metal film on a wafer. The metal film is formed in the metal film forming apparatus 3 by, for example, PVD (Physical Vapor Deposition).
The insulating film forming apparatus 4 forms an interlayer insulating film on a wafer. Formation of the interlayer insulating film in the insulating film forming apparatus 4 is performed by, for example, CVD (Chemical Vapor Deposition).

  The control unit 300 is a computer, for example, and has a program storage unit (not shown). The program storage unit stores a program for controlling wafer processing in the substrate processing system 1. The program storage unit also stores a program for controlling the operation of driving systems such as the above-described various processing apparatuses and transfer apparatuses to realize wafer processing in the substrate processing system 1. The program is recorded on a computer-readable storage medium H such as a computer-readable hard disk (HD), a flexible disk (FD), a compact disk (CD), a magnetic optical desk (MO), or a memory card. May have been installed in the control unit 300 from the storage medium.

  The substrate processing system 1 according to the present embodiment is configured as described above. Next, wafer processing performed using the substrate processing system 1 configured as described above will be described. FIG. 5 is a flowchart showing an example of main steps of such wafer processing. 6 and 7 are views showing the state of the wafer during the wafer processing. FIGS. 6A to 6D and FIGS. 7A to 7E show the top surface of the wafer, and FIGS. 6A to 6D and FIGS. 7A to 7E are diagrams. This corresponds to FIGS. 6 (A) to (D) and FIGS. 7 (A) to (E), and shows a cross section of the wafer center. FIG. 8 is a diagram illustrating an example of a surface modifying fluid (also referred to as a surface modifier).

First, a cassette C containing a plurality of wafers W on which a base film is formed is carried into the cassette station 10 of the pattern forming apparatus 2. Each wafer W in the cassette C is sequentially transferred to the heat treatment apparatus 40 of the processing station 11 and the temperature is adjusted.
On the wafer W of this example, as shown in FIGS. 6A and 6A, metal films 401 and insulating films 402 as base films are formed so as to be alternately arranged in a straight line.

  Thereafter, the wafer W is transferred to the surface modification device 41, and is insulated by the surface modification fluid among the metal film 401 and the insulating film 402 of the base film of the wafer W as shown in FIGS. 6B and 6B. Only the surface 402a of the film 402 is selectively surface-modified, and a DSA (Directed Self-Assembly) film can be formed (surface modification step; step S1 in FIG. 6). When a normal surface modification fluid is used, if both the metal film and the insulating film of the lower-character film are exposed on the surface, both are surface-modified. Therefore, in this embodiment, an organic compound gas having a Si—N bond is used as the surface modification fluid as shown in FIG. More specifically, trimethylsilyldimethylamine (TMSDMA) is used.

  When TMSDMA is used, for example, when the metal film 401 is a cobalt film (Co) and the insulating film 402 is a silicon oxide film formed by thermal oxidation, the insulating film 402 is selectively surface-modified. The trimethylsilyl group obtained by dissociating the Si—N bond of TMSDMA is bonded to the surface of the insulating film 402. The metal film 401 is not surface-modified. The selective surface modification treatment by TMSDMA is, for example, a treatment for holding TMSDMA in a gas atmosphere introduced at a predetermined flow rate together with nitrogen as a carrier gas for a predetermined time (for example, 5 minutes).

  After the selective surface modification, the wafer W is transferred to the heat treatment apparatus 40, heated, and temperature-adjusted.

  Thereafter, the wafer W is transferred to the block copolymer coating device 31. In the block copolymer coating apparatus 31, as shown in FIG. 6C and FIG. 6C, only the surface 402a of the insulating film 402 is selectively hydrophobized on the base film of the wafer W by PS-b. -PMMA403 is apply | coated (block copolymer application process. Process S2 of FIG. 6).

  Next, the wafer W is transferred to the polymer separation device 42 and subjected to heat treatment at a predetermined temperature. As a result, PS-b-PMMA 403 on wafer W is phase-separated into PMMA 404 and PS 405 as shown in FIGS. 6D and 6D (polymer separation step; step S3 in FIG. 6). Here, since the insulating film 402 of the base film is selectively surface-modified with a trimethylsilyl group including a functional group having a structure close to that of the PS 405, the PS 405 has a linear shape corresponding to the shape of the insulating film 402. To be separated. In addition, the PMMA 404 is phase-separated linearly corresponding to the shape of the metal film 401 so as to be positioned between the PS 405 and the PS 405. As a result, PMMA 404 and PS 405 are phase-separated into a desired shape.

  After the block copolymer 403 is phase-separated by the polymer separation device 42, the wafer W is transferred to the ultraviolet irradiation device 43. The ultraviolet irradiation device 43 irradiates the wafer W with ultraviolet rays, thereby breaking the bond chain of the PMMA 404 and causing the PS405 to undergo a crosslinking reaction (step S4 in FIG. 6).

  Next, the wafer W is transferred to the organic solvent supply device 30. In the organic solvent supply device 30, a polar organic solvent (polar organic solvent) is supplied to the wafer W. For example, IPA (isopropyl alcohol) is used as the polar organic solvent. As a result, the PMMA 404 whose bond chain has been cut by ultraviolet irradiation is dissolved by the organic solvent, and the PS 405 is selectively removed from the wafer W (polymer removal step; step S5 in FIG. 6). As a result, as shown in FIGS. 7A and 7A, a line pattern 406 is formed by PS405.

Thereafter, the wafer W is transferred to the delivery device 50 by the wafer transfer device 70,
Thereafter, the wafer is transferred to the cassette C of the predetermined cassette mounting plate 21 by the wafer transfer device 23 of the cassette station 10. Thereafter, the cassette C, that is, the wafer W is transferred to the metal film forming apparatus 3.

  In the metal film forming apparatus 3, a metal film is deposited by PVD on the wafer W on which the line pattern 406 is formed, and unnecessary metal films are appropriately removed by CMP, whereby FIG. 7B and FIG. ), A metal film 407 is formed so as to fill the line pattern 406 (wiring forming step, step S6 in FIG. 6). This metal film 407 constitutes a wiring. The underlying metal film 401 and the metal film 407 filled in the line pattern 406 are preferably formed of the same kind of metal.

Thereafter, the wafer W is transferred to an etching apparatus (not shown), the PS 405 is etched, and the metal film 407 protrudes from the insulating film 402 as shown in FIGS. 7C and 7C. Etching process, step S7 in FIG. The etching of PS405 can be performed by dry etching mainly composed of oxygen (O ₂ ), for example.

  Next, the wafer W is transferred to the insulating film forming apparatus 4, and an insulating film 408 is formed on the entire wafer W by CVD as shown in FIGS. 7D and 7D (insulating film forming step, Step S8 in FIG. Then, the wafer W is transferred to a polishing apparatus (not shown), and as shown in FIGS. 7E and 7E, the insulating film 408 is polished by CMP by the polishing apparatus to flatten the surface of the wafer W. In addition, the metal film 407 as the wiring is exposed (polishing step, step S9 in FIG. 6).

  Through the above steps, a desired film having a shape corresponding to the shape of the base film, in this example, a metal film and an insulating film can be formed on the base film having a predetermined shape on the substrate. In the present embodiment, since a desired film is formed by surface modification and DSA technology without using multi-patterning, even if the base film of the substrate is miniaturized, it is formed on the base film. A desired film having a shape corresponding to the shape of the base film can be easily formed. Furthermore, since multi-patterning is not used, the film can be formed at low cost.

  Moreover, the following effects are obtained by using gas as the surface modifier. That is, in general, a filter can collect foreign substances by orders of magnitude more than liquid. Therefore, the foreign substance can be made almost zero by making the surface modifying material a gas and passing the filter before the surface modifying treatment. In addition, gas is superior in terms of usage and uniformity.

  When TMSDMA gas is used as the surface modification fluid, the insulating film of the base film that is selectively surface-modified may be one that binds to the trimethylsilyl group of TMSDMA, and the metal film of the base film that is not selectively surface-modified is As long as the bond with the trimethylsilyl group of TMSDMA is small. In other words, based on the fact that the trimethylsilyl group is combined to make it hydrophobic, the underlying insulating film is a film having a contact angle of at least about 90 degrees with pure water when the following experiment is performed. Preferably, the metal film of the base film is preferably a film having a contact angle of 70 degrees or less.

In this experiment, samples of various membranes were organically washed in the order of acetone and IPA, then dried, and then irradiated with ultraviolet rays (wavelength 172 m) of 1000 mJ / cm ^{2 in} a nitrogen atmosphere (oxygen concentration of 50 ppm or less). Thereby, organic impurities adsorbed on the surface are removed. In addition, many alkyl groups (such as methyl groups and alkyl groups) may exist on the surface of the insulating film of the base film, and in this case, the reactivity of the surface with respect to the functional group obtained from the surface modification fluid is weak. Become. By irradiating with the ultraviolet rays, an alkyl group present on the surface is eliminated, and a site capable of reacting with a functional group (trimethylsilyl group in this example) obtained from the surface modification fluid is formed. In addition, when the reactivity with respect to the functional group of the surface of the insulating film of a base film is high, this ultraviolet irradiation is unnecessary.

  Then, with nitrogen flowing at 10 L / min (liters per minute) as a carrier gas, TMSDMA was injected into the vaporizer at room temperature, and each film sample was exposed to TMSDA gas for 5 minutes, and then PGMEA was used. Rinse and dry, then measure the contact angle of pure water of each membrane sample.

In the above experiment, a pure water contact angle of about 90 degrees, that is, a film suitable as an insulating film for a base film that is selectively surface-modified using a TMSDMA gas as a surface-modifying fluid, is described above. In addition to a silicon oxide film (SiO ₂ ) formed by thermal oxidation, it is an insulating film containing Si such as a silicon oxynitride film (SiON), a silicon nitride film (SiN), a silicon-containing antireflection coating film (SiARC). Other insulating films containing Si include, for example, Applied Materials (Applied Materials).
Materials added by the product Black Diamond manufactured by Materials) Carbon-added silicon oxide film (SiOC-based film), and a film (SOG) formed by dissolving silica (SiO ₂ ) in a solvent and spin-coating the liquid Can be mentioned. Also, the Si semiconductor film has a contact angle of about 90 degrees and can be used as a non-conductor film as a base film. In the following description, for the sake of simplicity, it is assumed that an SI semiconductor film is included in an insulator containing Si.

  On the other hand, when the pure water contact angle is 70 degrees or less in the above-described experiment, that is, when a TMSDMA gas is used as the surface modification fluid, a film suitable as a metal film of the base film is the above Co, A nickel film (Ni), a titanium film (Ti), a titanium nitride film (TiN), a tungsten film (W), a tungsten nitride film (WN), a copper film (Cu), and a ruthenium film (Ru). Note that a metal film that is easily bonded to the dimethylamino group of TMSDMA or a metal film that is difficult to bond may be used. Since Co and Ni can be formed by plating, they are more suitable as a metal film for the base film.

  In the above example, the metal film (wiring) is formed on the metal film included in the base film of the substrate, but a desired film other than metal is formed on the metal film included in the base film of the substrate. You may do it. Further, a desired film may be formed on an insulating film other than the metal film included in the base film of the substrate.

<Second Embodiment>
In the first embodiment, TMSDMA gas is used as the surface modification fluid for selectively modifying the surface of the base film. However, in the second embodiment, TMSDMA liquid is used as the surface modification fluid.

  When a TMSDMA liquid is used as the surface modifying fluid, the insulating film of the base film that is selectively surface modified is preferably a film having a pure water contact angle of about 90 degrees when the following experiment is performed. The metal film of the base film is preferably a film having at least the same contact angle of 70 degrees or less.

In this experiment, samples of various membranes were organically washed in the order of acetone and IPA, then dried, and then irradiated with ultraviolet rays (wavelength 172 m) of 1000 mJ / cm ^{2 in} a nitrogen atmosphere (oxygen concentration of 50 ppm or less). Then, after immersing each film sample in liquid TMSDMA for 5 seconds, rinsing with PGMEA and drying, the contact angle of pure water of each film sample is then measured.

A film having a pure water contact angle of about 90 degrees in the above-described test, that is, a film suitable as an insulating film for a base film that is selectively surface-modified using a TMSDMA liquid as a surface-modifying fluid is SiO _2. SiON, SiN, SiARC, SiOC-based films, SOG, and other Si-containing insulating films, and Si semiconductor films.

  On the other hand, when the contact angle of pure water is 70 degrees in the above-described test, that is, when a TMSDMA gas is used as the surface modifying fluid, films suitable for the metal film of the base film are Co, Ni, Ti, TiN. , W, WN, Cu, Ru.

<Third Embodiment>
In the first and second embodiments, TMSDMA gas or liquid is used as the surface modification fluid for selectively surface-modifying the undercoat film. However, in the third embodiment, diphenylmethyldimethylaminosilane is used as the surface modification fluid. (DPMDMAS) gas is used. This is effective because diphenylmethylsilane contained in DPMDMAS selectively reacts with the insulating film.

  In the case of using DPMDMAS gas as the surface modification fluid, the insulating film of the base film that is selectively surface-modified with diphenylmethylsilane has a contact angle of at least about 80 degrees with pure water when the following experiment is performed. A film is preferable, and the metal film of the base film is preferably a film having at least the same contact angle of 70 degrees or less. This is because the surface reacted with diphenylmethylsilane has hydrophobicity.

In this experiment, samples of various membranes were organically washed in the order of acetone and IPA, then dried, and then irradiated with ultraviolet rays (wavelength 172 m) of 1000 mJ / cm ^{2 in} a nitrogen atmosphere (oxygen concentration of 50 ppm or less). Then, with nitrogen flowing at 10 L / min (liters per minute) as a carrier gas, DPMDMAS is injected into a vaporizer at 180 ° C., and each film sample is exposed to the DPMDMAS gas for 5 minutes. At this time, the wafer and the piping system path to the wafer are all heated to 120 ° C. Then, it rinses with PGMEA and dries, Then, the contact angle of the pure water of the sample of each film | membrane is measured.

A film having a pure water contact angle of about 80 degrees in the above-described test, that is, a film suitable as an insulating film for a base film that is selectively surface-modified when a DPDMAS gas is used as a surface-modifying fluid, is TMSDMA. As in the case of using this gas, it is an insulating film containing Si such as SiO ₂ , SiON, SiN, SiARC, SiOC-based film, SOG, or Si semiconductor film.

  On the other hand, in the case where the pure water contact angle is 70 degrees in the above-described test, that is, when a PMPMAS gas is used as the surface modification fluid, a film suitable as a metal film of the base film uses a TMSDMA gas. Similarly, Co, Ni, Ti, TiN, W, WN, Cu, and Ru.

  The liquid of DPMDMAS requires a long time until the surface modification is completed, that is, it takes a long time for the diphenylmethylsilyl group of DPMDMAS to be bonded. preferable.

  Further, when the boiling point of the surface modifier is high as in the DMPDMAS of this embodiment, it is preferable to supply it as a gas by heating, and in order to prevent dew condensation on the way to the wafer, It is preferable to heat the wafer body.

  Further, the surface modifier selectively changes the surface of the insulating film of the base film and enables DSA using PS-b-PMMA. The TMSDMA used in the first to third embodiments The organic compound is not limited to DPMDMAS, and may be another organic compound having a Si-N bond.

Other surface modifiers that enable DSA using PS-b-PMMA by selectively surface-modifying an insulating film containing Si include organic compounds having Si-N bonds, and R _{1 in} FIG. It is considered that at least one of ˜R ₃ includes a molecule having a PS structure or a molecule similar to the PS structure (for example, C ₂ H ₄ C ₆ H ₅ ). Further, an organic compound having a Si—N bond, which has a PS property by combining a plurality of R1 to R3 in FIG. 8, may be used. Furthermore, in the organic compound having a Si—N bond used for the surface modifier, the number of substituted amino groups in which the hydrogen atom of the amino group is substituted with a methyl group is not limited to one, and a plurality of substituted amino groups may be used. The group may be substituted with an ethyl group or a propyl group, or may be a normal amino group (having no hydrogen atom substituted) instead of a substituted amino group.
From the viewpoint of the reaction rate, it is an organic compound having a Si—N bond, and R 2 and R 3 in FIG. 8 are methyl groups, and R 1 is (C ₈ H ₈ ) _n (CH ₂ ) ₃ . Since the surrounding steric hindrance is reduced, the reaction rate can be increased.

  Note that when the surface modification of the insulating film containing Si is selectively performed, it may be made hydrophilic instead of being hydrophobized. In this case, as the surface modifier, an organic compound having a Si—N bond and containing a molecule having a structure close to PMMA in at least one of R1 to R3 in FIG. 8 can be used.

<Fourth embodiment>
In the first to third embodiments, the insulating film of the base film is selectively surface-modified. In the fourth embodiment, the metal film of the base film is selectively surface-modified.
As a surface modifier for selectively modifying the metal film of the base film, an organic compound having a functional group that modifies only the metal without modifying the surface of the insulating film, for example, alkylthiol, alkylselenolate, dialkyldiselenide , Alkyl tellurates and the like can be used.
A specific example of alkylthiol includes octadecanethiol.

A gold film or a silver film can be used as the metal film of the base film in the present embodiment.
Further, the surface modifier of the present embodiment may be a liquid or a gas.

<Modification of the first to fourth embodiments>
When used as a gas, the surface modifier may be diluted with an organic solvent that does not react with the surface modifier or the surface modification target surface in order to improve the supply amount controllability and the handleability.
Moreover, the surface modifier may contain not only one type but a plurality of types. For example, a liquid obtained by mixing a surface modifier liquid for selectively modifying the surface of an insulating film and a liquid of a surface modifier for selectively modifying a metal film may be used for selective surface modification by vaporizing. Good.

  The surface modifier that selectively modifies the surface of the insulating film and the surface modifier that selectively modifies the surface of the metal film may be vaporized separately, and the vaporized materials may be mixed and used for selective surface modification. The vaporized materials may be supplied in order.

  Further, two or more kinds of surface modifiers may be supplied as a surface modifier that selectively colors one of the insulating film and the metal film. For example, both DPMDMAS and TMSDMA react with the insulating film and hardly react with the metal surface. Therefore, both DPMDMAS and TMSDMA are supplied, and the order of supply is DPMDMAS which is difficult to react due to large steric hindrance first. By supplying TMSDMA that is easy to react with small steric hindrance after being supplied, the target surface modification can be performed on the insulating film.

<Fifth embodiment>
9A and 9B are views showing the state of the wafer during wafer processing according to the fifth embodiment. FIGS. 9A to 9E show the top surface of the wafer, and FIGS. FIGS. 9A to 9E correspond to FIGS. 9A to 9E and show a cross section of the wafer center.

  The wafer processing according to the fifth embodiment is the same up to the polymer separation step of the wafer processing according to the first embodiment. As shown in FIGS. 9A and 9A, in the wafer W after polymer separation, the PS 405 is formed in a linear shape corresponding to the shape of the insulating film 402 of the base film, and the PMMA 404 is the PS 405 and the PS 405. Are formed in a straight line shape corresponding to the shape of the metal film 401 of the base film. The reason why the PS405 and the PMMA 404 are formed in a shape corresponding to the shape of the base film is that the surface of the insulating film 402 is modified with a trimethylsilyl group, and the surface of the insulating film 402 is close to the PS state. .

Here, since the surface of PS 405 after phase separation is naturally PS, the surface of PS 405 after phase separation is in the same state as the surface-modified insulating film 402.
Therefore, when PS-b-PMMA is re-applied from the block copolymer coating device 31 to the wafer W after phase separation and heat treatment is performed at a predetermined temperature by the polymer separation device 42, the re-coated PS-b- PMMA is phase-separated according to the shape of PS405 previously phase-separated. In other words, when PS-b-PMMA is re-applied from the block copolymer coating device 31, and heat treatment is performed at a predetermined temperature by the polymer separation device 42, as shown in FIGS. 9B and 9B. Then, a PMMA double laminated film 501 having the same shape as the insulating film 402 and a PS double laminated film 502 having the same shape as the metal film 401 are formed.

  Similarly, when PS-b-PMMA is further recoated from the block copolymer coating device 31 and heat treatment is performed at a predetermined temperature by the polymer separation device 42, as shown in FIGS. 9C and 9C. In addition, a PMMA triple stacked film 503 having the same shape as the insulating film 402 and a PS triple stacked film 504 having the same shape as the metal film 401 are formed.

  Then, the ultraviolet irradiation device 43 irradiates the wafer W with ultraviolet rays to break the PMM bond chain of the triple laminated film 504 and cross-link the PS 405 of the triple laminated film 503. Thereafter, a polar organic solvent is supplied from the organic solvent supply device 30 to the wafer W, whereby the PMMA laminated film 503 whose bond chain is cut is dissolved by the organic solvent, and three layers of PMMA are selected from the wafer W at a time. Removed. As a result, as shown in FIGS. 9D and 9D, a deep line pattern 505 is formed by the triple stacked film 504 of PS.

  Thereafter, in the metal film forming apparatus 3, a metal film is deposited by PVD on the wafer W on which the line pattern 505 is formed, an unnecessary metal film is appropriately removed by CMP, and the triple stacked film 504 of PS is etched, As shown in FIGS. 9E and 9E, the thick metal film 506 protrudes from the insulating film 402.

  In this embodiment, since the removal of the phase-separated polymer and the formation of a metal film for wiring, that is, a desired film are collectively performed, a thick wiring (metal film) can be formed in a short time. .

<Reference example>
In the wafer processing of the reference example, first, the surface of the wafer is first modified to have a desired shape so that DSA using the block copolymer can be performed. Conventional techniques can be used for this surface modification.

  And the block copolymer which consists of 1st polymers, such as PS-b-PMMA, and 2nd polymer is apply | coated to the surface / application surface by which the surface modification of the wafer was carried out using a block copolymer application | coating apparatus.

  Subsequently, for the wafer coated with the block copolymer. Heat treatment is performed at a predetermined temperature using a polymer separation device, and phase separation is performed into a first polymer and a second polymer.

  Thereafter, without removing any polymer, the block copolymer is re-coated on the phase-separated wafer using a block copolymer coating apparatus, and heat treatment is performed again at a predetermined temperature using the polymer separation apparatus. Thus, a double laminated film of the first polymer having a desired shape and a double laminated film of the second polymer having another desired shape are obtained.

  Further, by repeating the recoating of the block copolymer and the phase separation, a laminated film of the first polymer having a thicker desired shape and a laminated film of the second polymer having another desired shape are obtained.

  Then, either the first polymer laminated film or the second polymer laminated film is selectively removed using an ultraviolet irradiation device, an organic solvent supply device, or the like.

  Using any of the remaining laminated films, for example, a desired film can be formed as in the fifth embodiment described above. Etching may be performed using any of the remaining laminated films as a mask. When etching is performed, the stacked film serves as a mask, that is, since the mask is thick, etching resistance can be increased.

  In the above description, the example of forming the line & space pattern has been described, but the present invention can also be applied to the case of forming a hole pattern.

  The preferred embodiments of the present invention have been described above with reference to the accompanying drawings, but the present invention is not limited to such examples. It is obvious for those skilled in the art that various modifications or modifications can be conceived within the scope of the idea described in the claims, and these naturally belong to the technical scope of the present invention. It is understood. The present invention is not limited to this example and can take various forms. The present invention can also be applied to a case where the substrate is another substrate such as an FPD (flat panel display) other than a wafer or a mask reticle for a photomask.

  The present invention is useful when a desired film is formed on a base film having a fine pattern according to the base film.

DESCRIPTION OF SYMBOLS 1 ... Substrate processing system 2 ... Pattern formation apparatus 3 ... Metal film formation apparatus 4 ... Insulating film formation apparatus 30 ... Organic solvent supply apparatus 31 ... Block copolymer coating apparatus 41 ... Surface modification apparatus 42 ... Polymer separation apparatus 43 ... Ultraviolet irradiation Apparatus 300 ... Control unit 401 ... Metal film 402 ... Insulating film 403 ... Block copolymer 404 ... PMMA
405 ... PS
406 ... Line pattern 407 ... Metal film 408 ... Insulating film

Claims (15)

The base film of the substrate includes a first film and a second film, and a pattern having a shape corresponding to the shape of the first film is formed on the first film, or on the second film A substrate processing method for forming a pattern having a shape corresponding to the shape of the second film,
A surface modification step of surface-modifying either the first film or the second film of the base film with a surface modification fluid;
An application step of applying a block copolymer containing a first polymer and a second polymer to the base film;
A phase separation step of heating the substrate and phase-separating the block copolymer into a shape corresponding to the shape of the first film and the shape of the second film;
And a removing step of selectively removing either one of the first polymer and the second polymer of the block copolymer phase-separated.   A film forming step of forming a desired film so as to fill a portion where either one of the first polymer and the second polymer is selectively removed is included. Item 2. The substrate processing method according to Item 1.   The block copolymer is re-coated on the phase-separated block copolymer, and the re-coated block copolymer has a shape corresponding to the shapes of the first polymer and the second polymer that have already been phase-separated. The substrate processing method according to claim 1, further comprising a laminating step of phase separation.   The substrate processing method according to claim 3, wherein the stacking step is performed a plurality of times.   In the removal step, the block copolymer phase-separated in the phase separation step and the block copolymer phase-separated in the lamination step are combined with either the first polymer or the second polymer. The substrate processing method according to claim 3, wherein the substrate processing method is selectively removed.   Including a film batch forming step of forming a desired film so as to fill a portion where either one of the first polymer and the second polymer is selectively removed collectively. The substrate processing method according to claim 5.   The substrate processing method according to claim 1, wherein the first film is a metal film, and the second film is a semiconductor film or an insulating film.   The substrate processing method according to claim 7, wherein the metal film is formed of cobalt, nickel, titanium, titanium nitride, tungsten, tungsten nitride, copper, or ruthenium.   The substrate processing method according to claim 7, wherein the semiconductor film or the insulating film is a silicon semiconductor film or an insulating film containing silicon.   The substrate processing method according to claim 9, wherein the surface modification fluid is a gas or a liquid of a compound having a Si—N bond.   The substrate processing method according to claim 10, wherein the compound having a Si—N bond is trimethylsilyldimethylamine or diphenylmethyldimethylaminosilane.   10. The substrate processing method according to claim 7, wherein the surface modification fluid is a gas or a liquid of a compound having a functional group that reacts with the metal film. 11.   A program that operates on a computer of a control unit that controls the substrate processing system so that the substrate processing method according to claim 1 is executed by the substrate processing system.   A readable computer storage medium storing the program according to claim 7. The base film of the substrate includes a first film and a second film, and a pattern having a shape corresponding to the shape of the first film is formed on the first film, or on the second film A substrate processing system for forming a pattern having a shape corresponding to the shape of the second film,
A surface modification device for modifying the surface of either the first film or the second film of the base film with a surface modification fluid;
An applicator for applying a block copolymer containing a first polymer and a second polymer to the base film;
A phase separation device that heats the substrate and phase-separates the block copolymer into a shape corresponding to the shape of the first film and the shape of the second film;
And a polymer removing device that selectively removes any one of the first polymer and the second polymer of the block-separated block copolymer.