JP3358792B2 - Thin film forming apparatus and thin film forming method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thin film forming apparatus and method for continuously transferring a thin film to a substrate in a semiconductor manufacturing apparatus.

[0002]

2. Description of the Related Art A thin film forming method relating to an electronic component mainly includes:
Sputtering, chemical vapor deposition, vapor deposition, coating,
It is roughly divided into plating method and the like. When the area of a substrate on which a thin film is to be formed is small, any one of these methods can be used to handle an electronic component to be realized. However, as the diameter of a wafer used in the manufacture of LSIs increases and the area of a liquid crystal panel or the like increases, a thin film forming method suitable for the increase in diameter has become necessary. In addition, demands for not only an increase in diameter but also a technique for flattening a surface in forming a thin film are increasing. In particular, taking the field of LSI multilayer wiring technology as an example, in order to realize this multilayer wiring, it is necessary to completely flatten the surface of the insulating film.

Heretofore, as typical techniques of this flattening method, (1) SOG (Spin-On-Glass) method and PIQ method (K. Sat method)
o, S.Harada, A.Saiki, T.Kitamura, T.Okubo, and K.Muka
i, "A Nove1 Planar MultilevelInterconnection Techno
logy Utilizing Polyimide ", lEEE Trans.Part HybridPa
ckage., "PHP-9,176 (1973)" (2) Etchback method (P. Elikins, K. Reinhardt, and R.
Layer, "A planarization Process for double metal CM
OS using Spin-on Glass asaSacrificial Layer, "Proce
eding of 3rd lnternational IEEE VMIC Conf., 100 (198
6)) (3) Lift-off method (K. Ehara, T. Morimoto, S. Muramoto,
and S.Matsuo, "Planar lnterconnection Technology fo
r LSI Fabrication Utilizing Lift-off Process ", J. Ele
ctrochem. Soc ", Vol. 131, No. 2, 419 (1984)) and the like.

[0004] With respect to the SOG method, it is difficult to achieve complete flattening because the fluidity of the film is used.

The etch-back method is the most widely used technique, but has a problem of dust generation due to simultaneous etching of a resist and an insulating film, and is not an easy technique in terms of dust management.

The lift-off method has not been put to practical use because the stencil material to be used is not completely melted at the time of lift-off, so that it cannot be lifted off, and the controllability and yield are insufficient.

As a simple planarization method, 1978, CY
Ting et al. Proposed a bias sputtering method (CYTi
ng, VJVivalda and HGSchaefer, "Study of Planariz
edSputter-Deposited-SiO ₂ ", J.Vac.Sci.Technol. 15,
1105 (1978)).

Further, as a method for further applying to fine wiring by using a bias application, see, Machi
da et al. proposed a bias ECR method (K. Machida
andH.0ikawa, "SiO ₂ Planarization Technology with Bi
asing and ElectronCyclotron Resonance Plasma Depos
ition for SubmicronInterconnections, "J.Vac.Sci.Tec
hnol.B4,818 (1986)).

In these methods, a film is formed by sputtering or EC.
This is performed by an R plasma CVD method, an rf bias is applied to the substrate, sputtering occurs on the sample substrate, and a film is formed while etching the convex portion by utilizing the angle dependency, thereby realizing planarization. The features of these technologies include that the film quality is good even when formed at a low temperature, and that the planarization process is easy and simple. However, there are problems such as low throughput and damage to elements.

In the 1990s, a polishing method was proposed as a method for planarizing the surface of an interlayer film (WJPatrick, WLGu).
thrie, CLStandley, PMSchiable, "Application ofChe
mical Mechanical Polishing to the Fabrication of V
LSI Circuit Interconnections ", J.E1ectrochem.Soc., V
ol. 138, No. 6, June, 1778 (1991)). This polishing method is a technology that has attracted attention because good flatness can be obtained,
If the quality of the insulating film is poor, good polishing characteristics cannot be obtained. Therefore, there is a problem that a high-quality insulating film is required at a low temperature and polishing characteristics are unstable.

In recent years, the diameter of semiconductor substrates has been increasing from 8 inches to 12 inches, for example.
When the above-described conventional technology is applied to a large-diameter semiconductor substrate, it is difficult to secure flatness and uniformity of film thickness from the viewpoint of controllability. As a result, the present situation is that the cost is increased, for example, by adding a complicated process in order to cope with an increase in diameter. Therefore, there is a demand for the development of a technology for forming a thin film at a low cost corresponding to an increase in diameter and for easily planarizing the thin film.

[0012]

As described above, when the prior art is applied to a large-diameter semiconductor substrate, it is difficult to ensure flatness and uniformity of film thickness from the viewpoint of controllability. There is a problem that adding a complicated process to cope with an increase in the diameter increases the cost.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned conventional problems. It is an object of the present invention to form a thin film continuously on a large-diameter substrate at low cost. It is an object of the present invention to provide a thin film forming apparatus and a thin film forming method capable of solving transfer failure of a thin film due to deflection of a sheet film and securing flatness and uniformity of the film thickness.

[0014]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention provides a sheet film supply apparatus, an apparatus for applying a thin film to a sheet film supplied by the sheet film supply apparatus, and drying the sheet film. A decompressible thin film forming chamber to which the formed sheet film is supplied, and a sample stage having a heating unit disposed in the thin film forming chamber,
A transfer plate for transferring the thin film to a substrate mounted on the sample stage opposite to the sample stage and the sheet film,
A sheet film supporting mechanism for supporting the sheet film in a state where tension is applied to the sheet film, a mechanism for penetrating a film portion to which a thin film of the sheet film is transferred, and a thin film being transferred and the film portion being penetrated. A sheet film collecting device for collecting the sheet film,
A mechanism for peeling the pierced film portion from the substrate. Further, the present invention is a thin film forming method of transferring a thin film formed on a sheet film to a semiconductor substrate by a transfer plate, wherein a step of forming a thin film on the sheet film, and forming the thin film on which the thin film is formed Supplying the sheet film to the thin film forming chamber, applying a tension to the sheet film, pressing the sheet film against the semiconductor substrate by the transfer plate, and transferring the thin film, and penetrating the film portion pressed against the semiconductor substrate. And a step of peeling off the pierced film portion from the semiconductor substrate.

In the present invention, tension is applied to the sheet film by the sheet film support mechanism, and the sheet film is pressed against the substrate by the transfer plate. Instead, the thin film can be reliably transferred to the substrate. Further, since the thin film to be transferred is formed on the sheet film, the transfer to a large-diameter substrate is enabled. Also,
In the present invention, a sheet film is supplied by a sheet film supply device, a film portion pressed against a semiconductor substrate is pierced by a piercing mechanism at the time of transferring a thin film, and the pierced film portion is separated from the substrate by a peeling mechanism. I do. The sheet film on which the thin film is transferred and the film portion is cut through is collected by a sheet film collecting device. Therefore, the transfer of the thin film can be performed continuously.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail based on an embodiment shown in the drawings. FIG. 1 is a schematic configuration diagram showing one embodiment of a thin film forming apparatus according to the present invention, and FIG. 2 is a plan view showing a main part of a sheet fill. In these drawings, a thin film forming apparatus 1 includes a thin film forming chamber 2 and a sheet film feeding apparatus 3 provided outside the thin film forming chamber 2.
A device 5 for applying and drying a thin film on the surface of the sheet film 4 supplied by the sheet film supply device 3, a transfer mechanism 7 for transferring the wafer 6 into the thin film forming chamber 2, and remaining on the transferred wafer 6. A peeling mechanism 8 for peeling off the film portion 4a and the film portion 4a on which the thin film is transferred.
A sheet film recovery device 13 for recovering the sheet film 4 that has been cut through, a sample table 9, a transfer plate 10, a sheet film support mechanism 11 disposed in the thin film forming chamber 2, and transfer of the thin film during transfer of the thin film. Film part 4a
And the like.

The pressure in the thin film forming chamber 2 is reduced by a vacuum pump (not shown). The sheet film supply device 3
1 includes a supply reel disposed on the left side of the thin film forming chamber 2 in FIG. 1, and the sheet film collecting device 13 includes a take-up reel disposed on the opposite side of the thin film forming chamber 2 from the supply reel. . The sheet film 4 is in the form of a roll, and is supplied by a supply reel 15 by intermittent rotation of a writing reel.
The film is applied intermittently, and the thin film is applied to the surface by a thin film coating / drying device 5 and dried by heating. Then, the thin film is transferred to the thin film forming chamber 2, the thin film is transferred to the wafer 6, and the winding reel It is wound up. The sheet film 4 is given a predetermined tension by being supported by the sheet film support mechanism 11. The sheet film support mechanism 11 includes a rotation shaft 17 and a tension roller 18 that applies a predetermined tension to the sheet film 4. The rotating shaft 17 is vertically movably disposed below the sheet film 4, and is configured to be lifted integrally with or separately from the sample stand 9 and to be pressed against the sheet film 4 when transferring a thin film. When tension is applied to the sheet film 4 by such a sheet film support mechanism 11, it is possible to prevent the sheet film 4 from being stretched during the transfer of the thin film, thereby preventing the sheet film 4 from being bent. The thin film coating / drying device 5 includes a coating device 5A and a drying device 5B.

The transport mechanism 7 comprises a transport belt or the like.
The wafer 6 is transferred onto the sample table 9, and is guided to the peeling mechanism 8 when the thin film is transferred. The sample stage 9 is provided with heating means 19 such as a heater for heating the wafer 6 mounted on the upper surface, and moves up and down integrally with or separately from the rotation shaft 17 of the sheet film support mechanism 11. The heating temperature by the heating means 19 is 2
It can be controlled from 5 ° C to 300 ° C. The transfer plate 1
Reference numeral 0 is disposed above the sample table 9 so as to oppose the sheet film 4 therebetween. The transfer plate 10 can move up and down, and moves down during the transfer of the thin film to move downward.
Is pressed onto the upper surface of the wafer 6 to transfer the thin film. At this time, the film portion 4a (see FIG. 2) on which the thin film has been formed is pierced by the piercing mechanism 12, and when the thin film is peeled off from the wafer 6 by the peeling mechanism 8 after being transferred, it is recovered by a recovery device (not shown). .

Next, a thin film forming operation of the thin film forming apparatus having the above configuration will be described with reference to FIGS. First, the heater 19 is heated by evacuating the thin film forming chamber 2. The transfer mechanism 7 transfers the wafer 6 onto the sample table 9.

Next, the sheet film 4 is fed out from the sheet film supply device 3, a thin film is applied to the surface of the sheet film 4, a thin film is formed by the drying device 5, and then guided into the thin film forming chamber 2. The sheet film 4 guided to the thin film forming chamber 2 is tensioned by applying a predetermined tension by the sheet film support mechanism 11. FIG. 3 shows this state.

Next, in order to transfer the thin film formed on the sheet film 4 to the wafer 6, the transfer plate 10 is lowered and brought into contact with the back surface of the sheet film 4 as shown in FIG. Further, the sample table 9 and the rotating shaft 17 of the sheet film support mechanism 11 are lifted integrally or separately, and the rotating shaft 17 is pressed against the sheet film 4. Further, when the transfer plate 10 is lowered and the sheet film 4 is uniformly stretched and pressed against the upper surface of the wafer 6, the thin film formed on the sheet film 4 is transferred to the wafer 6. FIG. 5 shows this state.
Therefore, the sheet film 4 does not bend, and the thin film can be reliably and flatly transferred to the wafer 6. Further, since the size of the sheet film 4 can be arbitrarily changed, the thin film can be transferred to the large-diameter wafer 6.

At the time of thin film transfer, the film portion 4a to which the thin film of the sheet film 4 is transferred is formed by the hollow mechanism 1
2 (FIG. 6). As a method of breaking through, a method of burning off thermally can be adopted,
In this embodiment, a rotary cutter is used to avoid contamination of the vacuum device. Also, the film portion 4a to be pierced is pierced so as not to cut off the sheet film 4 to enable continuous transfer.
In the present embodiment, an example is shown, which is larger than the wafer 6 and is hollowed out in a circle as shown in FIG. The film portion 4a is attached to the upper surface of the wafer 6 via the transferred thin film.

When the piercing of the film portion 4a is completed,
As shown in FIG. 7, the transfer plate 10 and the sample table 9 are moved in the directions opposite to those at the time of transfer, and are returned to their initial positions. Thereafter, as shown in FIG. 8, the wafer 6 on the sample table 9 is discharged to the outside of the thin film forming chamber 2 by the transfer mechanism 7 and guided to the peeling mechanism 8, and the film portion adhering to the upper surface of the wafer 6 is transferred. 4a is peeled off and collected in a collecting device. Further, the sheet film 4 on which the thin film is transferred and the film portion 4a is pierced is collected by the sheet film collecting device 13.

Hereinafter, by repeating the above operation, the transfer of the thin film to the wafer 6 can be continuously performed.

Here, in the present embodiment, an example is shown in which the transfer plate 10 and the sample table 9 are disposed so as to be vertically movable.
Not limited to this, it goes without saying that the thin film can be similarly transferred by pressing only one of the sheet films 4 against the wafer 6 by moving one of them.

[0026]

Next, an example in which an insulating film is formed on a semiconductor substrate using the above-described thin film forming apparatus will be described. FIG. 9 is a sectional view of the sheet film. In this embodiment, a thermoplastic resin film is used as the sheet film 4, and a coating liquid for forming a silica-based insulating film containing one or more polysilazanes of an SOG material represented by the following Chemical Formula 1 is used as the thin film. Was applied on the sheet film 4 to form an insulating film 30.

[0027]

Embedded image

Here, in the above Chemical Formula ₁ , R ₁ , R
₂ and R ₃ are each independently a hydrogen atom or a carbon atom 1
To 8 alkyl groups, aryl groups and alkoxyl groups. In this embodiment, the insulating film 30 is formed with a thickness of 1 μm or more.

FIG. 10 shows an example in which the insulating film 30 is transferred to the semiconductor substrate 6 on which the electrode wiring 31 is formed by using the sheet film 4 shown in FIG. The structure shown in FIG. 10A uses Al as the electrode wiring 31 in this embodiment. A
The electrode wiring 31 of 1 was formed by forming Al to a thickness of 5000 angstroms by a sputtering method, followed by patterning by a photolithography step, and then processing by dry etching.

FIG. 10B shows a method of transferring an insulating film to a substrate by the present apparatus and method. After placing the semiconductor substrate 6 on the sample stage 9 shown in FIG.
Was evacuated. The degree of vacuum was set to 10 Torr or less. In the practice of the present invention, the thin film transfer has a weight of 5 kg,
The heating was performed at a heating temperature of 150 ° C. for a heating time of 10 minutes.

FIG. 10C is a cross-sectional view showing a state in which the insulating film 30 is transferred to the semiconductor substrate 6 and then the sheet film 4 is peeled off. FIG. FIG. 3 is a cross-sectional view of a semiconductor substrate showing a formed structure. A heat treatment step was performed to perform firing after peeling. In this embodiment, the heat treatment was performed at a temperature of 400 ° C. for a time period of 30 minutes in a steam atmosphere. The insulating film 30 finally obtained
Was 1.0 μm. Further, as shown in FIG. 10D, a structure having a flat surface was realized by using the apparatus of the present invention.

In the present invention, an example in which the present invention is applied to a semiconductor substrate has been described. However, the present invention is not limited to this.

[0033]

As described above, according to the thin film forming apparatus and the thin film forming method of the present invention, since no bending occurs, the transfer failure due to the bending can be solved, and the thin film can be stably and easily flattened. And a technology that can be applied to a large-area substrate at low cost can be easily realized. In addition, since the sheet film can be automatically supplied, the transfer of the thin film can be continuously performed, and an apparatus having high productivity can be provided.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram showing one embodiment of a thin film forming apparatus according to the present invention.

FIG. 2 is a plan view of a main part of the sheet film.

FIG. 3 is a view for explaining a thin film forming step.

FIG. 4 is a view for explaining a thin film forming step.

FIG. 5 is a view for explaining a thin film forming step.

FIG. 6 is a view for explaining a thin film forming step.

FIG. 7 is a view for explaining a thin film forming step.

FIG. 8 is a view for explaining a thin film forming step.

FIG. 9 is a cross-sectional view of a sheet film on which an insulating film is formed.

FIGS. 10A to 10D are views showing a step of transferring an insulating film to a semiconductor substrate.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Thin film formation apparatus, 2 ... Thin film formation chamber, 3 ... Sheet film supply apparatus, 4 ... Sheet film, 5 ... Thin film coating and heating apparatus, 6 ... Wafer, 7 ... Transport mechanism, 8 ... Peeling mechanism, 9
... Specimen stand, 10 ... Transfer plate, 11 ... Sheet film support mechanism, 12 ... Punch-through mechanism, 13 ... Sheet film recovery device, 17 ... Rotating shaft, 18 ... Tension roller, 30 ... Insulating film.

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) H01L 21/31 H01L 21/316

Claims (2)

(57) [Claims] 1. A sheet film supply apparatus, an apparatus for applying and drying a thin film on a sheet film supplied by the sheet film supply apparatus, and a decompressible thin film forming chamber to which the sheet film on which the thin film is formed is supplied And a sample stage having a heating means disposed in the thin film forming chamber, a transfer plate for transferring the thin film to a substrate mounted on the sample stage facing the sample stage and the sheet film, A sheet film supporting mechanism for supporting the sheet film in a state where tension is applied to the sheet film, a mechanism for penetrating a film portion to which a thin film of the sheet film is transferred, and a thin film being transferred and the film portion being penetrated. A sheet film collecting device for collecting the sheet film; and a mechanism for separating the cut-out film portion from the substrate. And a thin film forming apparatus. 2. A thin film forming method for transferring a thin film formed on a sheet film to a semiconductor substrate by a transfer plate, comprising: forming a thin film on the sheet film; A step of supplying the sheet film to the formation chamber, a step of applying a tension to the sheet film and pressing the sheet film against the semiconductor substrate by the transfer plate to transfer the thin film, and a step of penetrating a film portion pressed against the semiconductor substrate. Separating the cut-out film portion from the semiconductor substrate.