JP3532691B2 - Method of manufacturing aperture, mold for manufacturing aperture, and method of manufacturing the same - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing an aperture for beam shaping used for drawing a pattern on a substrate, an LSI manufacturing apparatus equipped with this aperture, a mold for manufacturing the aperture and a manufacturing method thereof.

[0002]

2. Description of the Related Art As an aperture for forming a beam in an LSI manufacturing apparatus, for example, an electron beam exposure apparatus, Pt is conventionally used.
A heavy metal thin plate such as or Ta machined (punched and formed) has been used. However, since these apertures are machined, there is a problem that sufficient machining accuracy cannot be obtained.

Further, in order to cope with the high precision of the LSI manufacturing apparatus, there is a method of manufacturing an aperture applying a lithography technique for the purpose of improving the processing accuracy of the aperture.
It has been developed in recent years. Examples thereof include those formed by etching a Si thin film provided on a Si substrate, those formed by patterning an Au thin film on a Si substrate by a lift-off method, and the like. The method of forming the aperture pattern using the Au thin film has an advantage that the processing accuracy can be easily improved because the thickness of the Au thin film used for the aperture can be made thinner than that of the Si thin film. .

Conventionally, such an Au aperture has been manufactured by the following steps. Here, a method of forming an aperture pattern by Au plating using a thick film resist or the like provided on a Si single crystal substrate as a template will be described as an example.

It is assumed that the acceleration voltage of the electron beam exposure apparatus equipped with the beam shaping aperture is 50 keV. Fifty
The maximum range of the keV electron beam for Au (bulk: Au in general) is 3.7 μm. On the other hand, the density of the Au film formed by the electrolytic plating method can be 95% or more of the bulk. Therefore, it is sufficient that the Au thin film used as the aperture has a thickness of about 4 μm.
In this case, the thickness of the mold for Au plating may be about 5 μm. As the template, a positive resist for electron beam, for example, PMMA (polymethylmethacrylate) resist can be used.

The manufacturing process of the Au aperture will be briefly described. Pd used as a base for plating on a Si single crystal substrate
Etc., and then apply a resist film with a thickness of 5 μm,
Bake. After that, a pattern serving as a template is drawn using an electron beam exposure apparatus. Then, the resist is developed to form a resist template. Next, an Au thin film is formed on the substrate on which the resist template is formed by electrolytic plating. After that, the mold is removed, and the K
An opening including an aperture is provided in the substrate by using an anisotropic etching method using an OH (potassium hydroxide) aqueous solution or the like.

FIG. 16 (a) is a plan view showing the structure of a typical aperture, and FIG. 16 (b) is shown in FIG. 16 (a).
It is an a-16a sectional view. Here, for example, the outer shape L1 of the Si substrate 101 on which the aperture is mounted is set to 10 mm □, the thickness T of the Au thin film 106 provided near the center thereof is 4 μm, and the outer shape L2 is set to 1 mm □. The size L3 of the rectangular opening (aperture) is set to 200 μm □. The back surface of the substrate 101 in the aperture portion is provided with a tapered opening along the (111) plane.

Au plating film (aperture) as described above
Conventionally, the resist mold for patterning is formed as shown in FIGS. 17 (a) and 17 (b). Board 101
A plating base 102 is formed on top, and a resist mold 103 is formed on the plating base 102. Resist mold 103
In the above, the structure is such that the aperture forming portion is left in an island shape in the 1 mm square recessed region where Au is deposited. This island-shaped portion is a mold pattern 104 serving as an aperture pattern, and has a thickness of 5 μm and a rectangular shape with a side of 200 μm.

However, when the resist mold 103 has the above-mentioned thickness and size, the mold pattern 104 may be deformed by its own stress. Since this stress is a tensile stress, the rectangular corners in particular turn up or deform. Furthermore, even during plating
There is a problem that the mold is deformed by the stress of the plating film. This is a big problem because the shape accuracy of the mold pattern 104 directly reflects the shape accuracy of the aperture.

[0010]

As described above, in the prior art,
There has been a problem that sufficient processing accuracy of an aperture used in an LSI manufacturing apparatus that requires high accuracy cannot be obtained. The present invention has been made in view of the above circumstances, and an object thereof is a method of manufacturing an aperture with higher accuracy, an LSI manufacturing apparatus equipped with this aperture, a mold for manufacturing the aperture, and a method of manufacturing the same. To provide.

[0011]

As a typical first feature of the method of manufacturing an aperture of the present invention, in manufacturing an aperture including a step of forming a mold on a substrate and forming a thin film by a plating method, Regarding the island-shaped pattern on the mold side corresponding to the side wall of the aperture forming part, the aperture is formed using a mold having a nested pattern with a side wall inside.

Further features of the method for manufacturing the above-mentioned aperture are shown in (1) to (3) below. (1) In manufacturing an aperture including a step of forming a mold on a substrate by electron beam exposure and forming a thin film by a plating method, regarding the island-shaped pattern on the mold side corresponding to the side wall of the aperture forming part, the side wall on the inside Forming a mold having a nested pattern with the distance between the edge of the island pattern and the edge of the nested pattern longer than the radius of backscattering from the substrate by the electron beam. A step of forming a metal film on the substrate in the mold, a step of removing the mold, and etching a predetermined region from the back surface of the substrate on which the metal film is formed to form an opening. And a step of performing. (2) In manufacturing an aperture including a step of forming a mold on a substrate by electron beam exposure and forming a thin film by a plating method, in the formation of the mold, an LSI manufacturing apparatus in which the acceleration voltage of the electron beam uses the aperture. The island-shaped pattern on the mold side corresponding to the side wall of the aperture forming part, which is equal to or larger than the accelerating voltage of the electron beam used for, and has a nested pattern with side walls on the inside, and Forming a mold in which the distance between the edge of the island-shaped pattern and the edge of the nested pattern is longer than the radius of backscattering from the substrate by the electron beam; and a metal on the substrate in the mold. A step of forming a film, a step of removing the template,
And etching a predetermined region from the back surface of the substrate on which the metal film is formed to form an opening. (3) In such a method of manufacturing an aperture, the mold is made of X-type in order to be used in an LSI manufacturing apparatus that handles an electron beam whose acceleration voltage exceeds 50 kV.
It is characterized by being formed by a line exposure method.

A second characteristic of the method for manufacturing an aperture according to the present invention is, as a typical second feature, in manufacturing an aperture for an LSI manufacturing apparatus that handles a charged particle beam or energy rays, an aperture by a focused ion beam (FIB) is used in the manufacturing process. The method is characterized by including a step of correcting the pattern.

Further features of the manufacturing method of the above-mentioned aperture are shown in (1) to (7) below. (1) In the step of correcting the aperture pattern by the FIB, the beam diameter of the focused ion beam is equal to or smaller than the dimensional accuracy required for the aperture. (2) The step of correcting the aperture pattern by the FIB is a step of etching a predetermined portion of the mold for forming the aperture pattern. (3) The step of correcting the aperture pattern by the FIB is a step of additionally forming a film on a predetermined portion of the mold for forming the aperture pattern. (4) The substance for forming a film additionally on a predetermined portion of the mold in the step of correcting the aperture pattern is carbon or hydrocarbon. (5) The step of correcting the aperture pattern by the FIB is a step of etching an edge portion of the aperture pattern of the thin film forming the aperture. (6) The FIB aperture pattern repairing step is a step of additionally forming a film on the edge portion of the aperture pattern of the thin film forming the aperture. (7) The substance additionally formed on the thin film forming the aperture is the same substance as this thin film or an alloy containing this substance, or Mo, Pd, Ag,
It is characterized by being one of Ta, W, Re, Pt, and Au, or an alloy containing these.

As a typical feature, the mold for manufacturing the aperture of the present invention relates to an island-shaped mold pattern corresponding to the side wall of the aperture forming portion, and has a pattern with a side wall inside the mold pattern. Characterize.

A typical feature of the method of manufacturing a mold for manufacturing an aperture of the present invention is that when forming an island-shaped mold pattern corresponding to a side wall of an aperture forming portion on a plate, the island-shaped mold pattern is formed. A step of simultaneously forming a nested pattern with a side wall inside the substrate by electron beam exposure, wherein the distance between the edge of the island pattern and the edge of the nested pattern is determined from the substrate by the electron beam. It is characterized by making it longer than the radius of backscattering.

According to the present invention, the following actions are involved. By applying the first typical feature of the above-described aperture manufacturing method, the area of the island-shaped pattern on the mold side is reduced, and the influence of stress on the corners and edges of the mold is reduced. Further, during plating, a plating film is formed not only on the outside of the island pattern of the mold but also on the inside. Therefore, the stress of the plating film can be canceled on the outer side and the inner side, and the mold deformation of the island pattern can be suppressed to be small. Since the shape accuracy of the mold is directly reflected on the shape accuracy of the aperture, highly accurate aperture processing is realized.

Further, by applying the second typical feature of the method of manufacturing the aperture, it is possible to selectively improve the precision of a part of the aperture and to adapt to various processing for forming the aperture.

If a mold for manufacturing the above-mentioned aperture is applied, the area of the island-shaped pattern on the mold side becomes small. Since the total stress is proportional to the length (size) of the film, reducing the pattern area reduces the influence of stress on the corners and edges of the thick film resist (mold).

Further, if the method of manufacturing the mold for manufacturing the aperture is applied, the influence of backscattering of the electron beam from the substrate due to the proximity effect is reduced. Achieve a vertical edge profile.

The present invention also provides an LSI manufacturing apparatus equipped with a high-precision aperture having the above characteristics. This expands the application range of the drawing pattern and contributes to a further leap in VLSI manufacturing.

[0022]

1 (a) and 1 (b) are respectively a plan view and a sectional projection view showing a process step which is a feature of a method of manufacturing a beam shaping aperture according to a first embodiment of the present invention. . A resist mold 13 is formed on the substrate 11. A plating base 12 is formed between the substrate 11 and the resist mold 13. On this resist mold 13, an island-shaped pattern (mold pattern) 14 on the mold side corresponding to the side wall of the aperture forming portion is formed. With respect to the island-shaped pattern 14, a nested pattern (dummy pattern) 15 with a side wall is provided inside. An Au thin film 16 is formed by a plating method using such a resist template 13. The distance between the edge of the mold pattern 14 (the outer edge of the island pattern) and the edge of the dummy pattern 15 (the inner edge of the island pattern) is ΔL.
And

By providing such a dummy pattern 15, the pattern area of the thick film resist mold pattern 14 is reduced. Since the total stress is proportional to the length (size) of the film, reducing the pattern area can alleviate the effect of stress on the corners and edges of the thick film resist forming the mold pattern 14. it can. As a result, the deformation of the mold due to stress can be reduced, and the dimensional accuracy at the time of finishing the aperture can be improved.

If such a dummy pattern 15 is provided, a plating film (Au thin film 16) is formed not only on the outside of the mold pattern 14 but also on the inside thereof during plating. Therefore, the stress of the plating film can be canceled between the outer side and the inner side, and the deformation of the mold pattern 14 for forming the aperture can be suppressed to be small. Therefore, also from this point, the dimensional accuracy of the aperture can be improved. In this case, since the plating film (Au thin film 16) formed in the area of the dummy pattern 15 inside the mold pattern 14 falls off from the back surface of the substrate during the step of forming the opening, it remains when the aperture is completed. Absent.

The method for manufacturing the aperture using the above mold will be described in more detail. 2 (a) to (e)
3A to 3C are cross-sectional views showing a method of manufacturing the aperture described in FIG. 1 in the order of steps. As shown in FIG. 2A, a silicon single crystal substrate having a main surface with a plane orientation of [100]
LPCVD of silicon nitride film (SiN) on both sides of 11
A 150 nm film is formed by (reduced pressure CVD method). Next, titanium (Ti) having a thickness of 100 nm and then palladium (Pd) having a thickness of 50 nm are continuously formed on the main surface of the substrate by a sputtering method. As a result, the plating base 12 is formed on the main surface of the substrate 11.

Next, as shown in FIG. 2 (b), PMMA
(Polymethylmethacrylate) resist thickness 4.3μm
Apply with. Next, the mold pattern 14 for the aperture and the dummy pattern 15 are exposed as described above using an electron beam exposure apparatus with an acceleration voltage of 50 kV. Next, the resist mold 13 is developed with a developing solution such as isopentyl acetate.
Development. Next, an RIE process is performed on the surface of the palladium (Pd) exposed by the development in order to remove the remaining resist residual film. By this process, the palladium layer used as the plating base and the Au plated
It is possible to improve the adhesion to the layer. Next, FIG.
As shown in (c), an Au thin film is formed by using an electroplating method.
16 is deposited to a thickness of 4 μm.

Next, as shown in FIG. 2 (d), a photoresist 17 is applied to the back surface of the substrate 11 and a double-sided exposure device is used.
The opening pattern is exposed by using a not-shown alignment mark provided in advance on the main surface and accurately aligning it with the portion to be the aperture. After developing the resist on the back surface of the substrate 11, the silicon nitride film (SiN) is patterned by RIE (Reactive Ion Etching). R
As the conditions of IE, for example, CHF ₃ : O ₂ = 40:
20 [sccm], pressure 60 mTorr, power 300
W for 2 minutes.

Thereafter, KO having a concentration of 20 w% and a liquid temperature of 90 ° C.
The silicon substrate is etched with an aqueous solution of H (potassium hydroxide). At this time, a jig is used on the side having the aperture pattern so that the KOH aqueous solution does not wrap around. In this etching, the silicon nitride film (SiN) provided on the main surface side serves as an etching stop layer.

Next, of the silicon nitride film remaining on the back surface of the substrate 11 and the exposed silicon nitride film of the KOH etching stop layer, CDE (Chem
icalDry Etching). The CDE condition is, for example, CF ₄ : O ₂ = 100: 100 [scc
m] and RF power of 300 W for 2 minutes.

Next, in order to penetrate the aperture portion, the titanium layer is removed using hydrofluoric acid, and the palladium layer is removed using a mixed acid of hydrochloric acid: nitric acid: acetic acid = 3: 30: 200. At this stage, the Au film formed in the dummy pattern 15 falls off. Next, the resist mold 13 that was the plating mold is removed by CDE. C
The DE condition is, for example, CF ₄ : O ₂ = 100: 5 [sc
cm] and an RF power of 300 W for 10 minutes.

Next, although not shown, the substrate is washed with a mixed solution of sulfuric acid and hydrogen peroxide. After that, gold is deposited to 50 nm on both surfaces of the substrate using a vacuum vapor deposition device. Next, if you do dicing and attach it to the holder,
The aperture is completed.

When an electron beam exposure apparatus is used to expose the resist mold 13 for plating described in the first embodiment, the following points should be noted. Care must be taken that the proximity effect associated with the exposure of the dummy pattern 15 does not deteriorate the dimensional accuracy of the mold pattern. Hereinafter, the second aspect of the present invention
Will be described as an embodiment.

FIGS. 3A and 3B are sectional views showing a comparison of the dimensional accuracy of the mold pattern when the distance ΔL between the edge of the mold pattern 14 and the edge of the dummy pattern 15 in FIG. 1 is changed. . That is, as shown in FIG.
The distance ΔL between the edge of the template pattern 14 and the edge of the dummy pattern 15 is the backscattering radius β of the electron beam used for writing.
When ΔL1 is shorter than b, the template pattern is affected by the backscattered electrons generated during exposure of the dummy pattern 15 (so-called proximity effect). The profile of the mold pattern 14 has an inverse taper shape, which may deteriorate the edge profile of the mold pattern to an unacceptable dimensional error.

As shown in FIG. 3B, the mold pattern 14
The distance ΔL between the edge of the dummy pattern 15 and the edge of the dummy pattern 15 is longer than the backscattering radius βb of the electron beam used for writing ΔL.
When 2, the influence of backscattered electrons (proximity effect) generated during exposure of the dummy pattern 15 is reduced, and
The 14 profiles are close to vertical, and the dimensional error can be reduced.

Here, βb is, for example, for a Si substrate, βb (μm) = 0.4 Rs = 1.25 × 10 ⁻² E ₀ ^1.7 (1) where Rs is the range E of the electron beam with respect to the substrate. ₀ can be determined as the electron beam energy (keV) (JSGreeneich, J.Vac.Sci.Tech
nol. 16, PP.1749-1753, 1979, and references therein). Therefore, it is necessary to make ΔL shown in FIG. 1 long enough to ignore the influence of the proximity effect, that is, longer than the backscattering radius of the electron beam used for exposure.

By the way, the thickness of the plating mold 13 is 4 μm.
When it is m or more, the acceleration voltage of the electron beam exposure apparatus for drawing the image is preferably high. If the acceleration voltage is not sufficiently high, the forward scattering component of the electron beam will increase and the edge profile of the mold pattern 14 will deteriorate.
If an electron beam exposure apparatus with an accelerating voltage of 50 kV or higher is used for exposing a resist mold having a thickness of 4.3 μm, the dimensional error of the edge profile can be suppressed to about 0.8 μm or less (see later).

Therefore, if an electron beam exposure apparatus with an accelerating voltage of 50 kV is used for the exposure of the mold 13 described in FIG. 2, the distance between the edge of the mold pattern 14 and the edge of the dummy pattern 15 shown in FIG. ΔL is 10 using the equation (1).
It may be about μm.

Next, a third embodiment will be described. When a thick film resist such as the mold 13 is drawn by the electron beam drawing apparatus as described above, the edge profile of the resist pattern deteriorates due to the forward scattering of the electron beam in the resist. For example, when PMMA resist is used, the edge profile has an inverse taper shape or an arc shape.

The forward scattering radius βf (unit: angstrom) of the electron beam in the resist is, for example, Gree.
As described in the neich reference, βf = 34.73Pe + 5.47Pe ² , ... (2-1). However, here, Pe is the number of events of elastic scattering, and for a PMMA resist, Pe = 413z ₀ (μm) / E ₀ (keV), (2-2) (For details, see JS Greeneich, J. Vac.Sci.Technol.1
6, PP.1749-1753, 1979, and references therein). Here, z ₀ is the film thickness of the PMMA resist,
E ₀ is the energy of the electron beam.

PMM calculated from equations (2-1) and (2-2)
The forward scattering radius of the electron beam in the A resist is shown in FIG. Here, the horizontal axis represents the acceleration voltage E ₀ of the electron beam writing apparatus equipped with the aperture, and the vertical axis represents the forward scattering radius (FWHM (full width half maximum) when the forward scattering is approximated by Gaussian). In FIG. 4, a solid line indicates a case where the accelerating voltage ( _denoted by E ₀₀ ) of the lithographic apparatus for writing the PMMA resist is the same as the accelerating voltage E _{0 of the} lithographic apparatus equipped with the aperture.
The forward scattering radius in the PMMA resist is shown, while the broken line draws the PMMA resist with a drawing device having an acceleration voltage E ₀₀ = 100 kV for any E ₀ (that is, for any PMMA film thickness). This shows the forward scattering radius in the case of performing. In this calculation, the film thickness of the PMMA resist is set to a value in which a margin of + 15% is considered in the maximum range of the electron beam energy of the drawing apparatus equipped with the aperture with respect to Au.

For example, the acceleration voltage E ₀ of the drawing apparatus equipped with the aperture is set to 50 kV. When the accelerating voltage EE ₀₀ of the drawing device for drawing the PMMA resist used for manufacturing this aperture is 50 kV, the film thickness of the PMMA resist is required to be 4.3 μm, and the forward scattering radius in this PMMA resist is 0. It becomes 0.83 μm (solid line in FIG. 4). On the other hand, when E ₀₀ is 100 kV, the forward scattering radius is 0.26 μm (broken line in FIG. 4).

The precision required for the edge profile of the aperture can be roughly determined by the reduction ratio of the drawing device and the precision required on the sample. For example, the reduction ratio is 1/8
0, and the required accuracy on the sample is 0.01 μm, the accuracy required for the edge profile of the aperture is 0.8
μm. As described above, when E ₀ = E ₀₀ = 50 kV, the forward scattering radius in the PMMA resist is 0.83.
μm, which is slightly worse than the accuracy required for the edge profile. Therefore, in order to satisfy the above-mentioned required accuracy, it is necessary to draw a resist with a drawing device having an acceleration voltage that satisfies E ₀ <E ₀₀ . For example, E ₀₀ = 1
At 00 kV, the forward scattering radius is 0.2 as described above.
When it is 6 μm and the reduction ratio is 1/80, it becomes 0.0033 μm on the sample. This is the required accuracy of 0.
It is sufficiently smaller than 01 μm.

As described above, in order to reduce the deterioration of the edge profile due to forward scattering in the resist, the accelerating voltage of the drawing device used for drawing the resist is made larger than the accelerating voltage of the drawing device equipped with the aperture. do it. For example, in the process of manufacturing the aperture described in the first embodiment, if a drawing device with an acceleration voltage of 100 kV is used for drawing the PMMA resist, the forward scattering radius becomes 0.26 μm and 50 kV as described above.
It is possible to obtain much better edge profile accuracy of the resist than in the case of drawing with the above apparatus.

Next, a fourth embodiment will be described.
In order to cope with the miniaturization of LSI, the acceleration voltage of the electron beam exposure apparatus may be increased. In particular, the minimum line width is 0.
An electron beam exposure apparatus having an accelerating voltage exceeding 50 kV is required to draw a pattern of 1 μm or less. The film thickness of the aperture used in such an exposure apparatus must be very large. For example, 100ke
The transmission limit film thickness of Au for a V electron beam is 11.5.
μm. Therefore, the film thickness of the PMMA resist mold for manufacturing the aperture made of the Au thin film needs to be 13.2 μm (with a margin of + 15% taken into consideration). A 13.2 μm-thick PMMA resist was used, and an acceleration voltage E ₀₀ = 1.
When writing with a writing device of 00 kV, the forward scattering radius in the resist is 1.82 μm (see FIG. 4).

By the way, as described above, E ₀ = E ₀₀ =
In the case of 50 kV, the forward scattering radius was 0.83 μm, which was slightly worse than the accuracy required for the resist edge profile. However, E ₀ = E ₀₀ = 10
In the case of 0 kV, as described above, the accuracy is far worse than that required for the edge profile. Thus, in the case of E ₀ = E ₀₀ (that is, using the drawing apparatus equipped with the aperture, PMMA serving as the template of the aperture is used).
When drawing a resist), the forward scattering radius in the resist increases as the acceleration voltage increases,
Therefore, the degree of deterioration of the accuracy of the edge profile increases. On the other hand, it is not easy to increase the accelerating voltage of the drawing device. Therefore, it is not easy to manufacture an aperture for a drawing device having a high acceleration voltage exceeding 50 kV with sufficient edge profile accuracy.

In order to accurately form the edge profile of such a resist template pattern having a high aspect ratio, the X-ray exposure method may be used. That is, in the aperture manufacturing method described with reference to FIG. 2, X-ray exposure is used for exposing the mold pattern with the PMMA resist.

Here, as the X-ray mask, for example, one having a structure in which a 2 μm thick SiC thin film is used for the membrane and a 1 μm thick Au thin film is used for the absorber is used. Also,
In this case, as the X-ray light source, for example, orbital radiation having a wavelength of 1 nm is used, and the irradiation amount is 5000 J / cm ² . For development after exposure, for example, isopropyl acetate may be used. The other manufacturing process may be based on the process described in FIG.

As described above, when the X-ray exposure is used for exposing the thick PMMA resist, the deterioration of the edge profile of the resist pattern can be suppressed to about 0.1 to 0.2 μm. Further, when the film thickness of the resist is several tens of μm, the wavelength of X-ray used for exposure may be further shortened (for example, 0.2 to 0.3 nm). In such a case, as the X-ray mask, for example, a Be thin film having a thickness of 20 μm for the membrane and an Au thin film having a thickness of 10 μm for the absorber may be used.

When the thickness of the resist becomes tens of μm, the deformation of the resist template due to the film stress of the resist becomes much more remarkable than when the film thickness is about 5 μm. Therefore, it is very effective to reduce the deformation of the island-shaped mold by forming a nested pattern inside the island-shaped mold to mitigate the influence of the film stress.

Since the shape accuracy of the mold is directly reflected on the shape accuracy of the aperture, it is possible to manufacture a highly accurate aperture by performing the above-described manufacturing method, and it is expected that the accuracy of the LSI manufacturing apparatus will be improved. For example, there are currently two types of electron beam exposure apparatuses used as lithography apparatuses: a reticle (mask) writing apparatus and a wafer direct writing apparatus. In these devices, a drawing method called a variable shaped beam (VSB) method or a character projection (CP) method is adopted in order to secure a sufficient throughput. Cha 53
Is a rectangle of 100 μm □, for example. In this case, the first
The beam that has passed through the shaping aperture 53 is shaped into 100 μm □. The shaped beam passes through the projection lens 54 and is projected onto the second shaping aperture 56. here,
The second shaping aperture 56 has, for example, an arrow shape in which a rectangle having a side length of 141 μm is rotated by 45 degrees and aligned with a rectangle having a side length of 100 μm. A shaping deflector 55 is provided upstream of the second shaping aperture 56, and the position of the first shaping aperture image projected on the second shaping aperture 56 can be changed. Depending on this position, a rectangular beam or a triangular beam having different sizes can be formed. The shaped beam is transmitted to the sub deflector 57, the objective lens 58, and the main deflector.
It is positioned by 59 and reaches a predetermined position on the sample surface (wafer) 60.

FIG. 5 is a block diagram showing a main part of an electron beam exposure apparatus as a fifth embodiment of the present invention. V
In the SB system, the two apertures in the figure, namely the first aperture
Beam shaping is performed using the shaping aperture 53 and the second shaping aperture 56. This will be described step by step. The electron beam emitted from the electron gun 51 passes through the condenser lens 52 and irradiates the first shaping aperture 53. Here, the first shaping aperture is the manufacturing method of the aperture as described in the first to fifth embodiments with respect to each of the first shaping aperture 53 and the second shaping aperture 56 in the LSI manufacturing apparatus as described above. If the above is applied, a more accurate LSI manufacturing apparatus can be expected.

Next, a more novel method for manufacturing the high precision aperture of the present invention will be described below. LSI
As device integration progresses, the requirements for accuracy and throughput of lithographic apparatus used in LSI manufacturing become more and more stringent. Some LSI device patterns include many repetitive patterns, particularly as represented by DRAM. Therefore, this repetitive pattern is formed on the above-mentioned second shaping aperture. As a result, the number of shots can be significantly reduced as compared with the VSB method. That is, it is possible to significantly increase the drawing throughput as compared with the VSB method. This drawing method is called a character projection (CP) method. Usually, in the electron beam exposure apparatus and the like, the CP method and the VSB method are used in combination. In this case, as the aperture plate, the CP aperture and the VSB aperture are provided in a mixed manner.

As described above, there is a method of applying the lithography technique to the manufacture of the aperture for the purpose of improving the processing accuracy of the aperture. That is, there are a method of forming an aperture pattern by etching a Si thin film provided on a Si substrate, a method of forming an Au thin film by plating after forming a template layer on the Si substrate, and the like. This is an example. Regarding the method of forming an aperture pattern by forming an Au thin film by plating, in the first embodiment, it was necessary to enhance the precision of the mold.

When the lithography technique is used for manufacturing the aperture, the degree of freedom regarding the shape and size of the aperture pattern is increased, and the patterning accuracy is improved. Therefore, not only the VSB aperture but also CP apertures having various shapes applicable to the CP drawing method can be accurately manufactured.

FIG. 6 shows an example of a typical beam shaping aperture (second shaping aperture) for CP + VSB. In this example, an Au thin film layer having a thickness of 4 μm and an outer shape of 3 mm □ is provided on a Si substrate of 10 mm □, and an aperture and a CP for a variable shaped beam (VSB) are provided on the Au thin film layer.
Apertures are arranged in an array. On the Si substrate, tapered openings are provided from the back surface at positions corresponding to the respective apertures. The VSB aperture is a rectangular type with a side of 200 μm, and the CP aperture is about 2
An aperture pattern corresponding to a part of the LSI pattern is included in the area of 00 μm □. Here, FIG.
The beam shaping aperture for CP + VSB of 1 is simply referred to as the second shaping aperture (61).

The reduction ratio of the optical system of the electron beam drawing apparatus equipped with such a second shaping aperture is, for example, 1 /
40 and the drawing accuracy is ± 0.005 μm or less on the sample surface, the dimensional accuracy of the aperture is ± 0.2.
It must be less than μm.

By the way, in the aperture manufacturing method applying the lithography technique, the method of forming the aperture pattern by using the Au thin film, as described above, improves the processing accuracy as compared with the aperture made of the Si thin film. Can be expected.

However, as described above, if the thickness of the resist used for the plating mold is 5 μm or more, a restrictive technique is required to accurately pattern the resist. It is difficult to adapt such a technique to the CP aperture. This is because a plurality of aperture patterns corresponding to a part of the LSI pattern are provided in a limited area, so that each aperture becomes finer.

Therefore, when an electron beam drawing apparatus is used as a resist mold for manufacturing such a fine CP aperture, the following problems may occur. (a) The edge profile of the resist pattern deteriorates due to the forward scattering of the electron beam in the resist and the back scattering from the substrate. (b) Edge roughness occurs due to resist heating. (c) The corners of the pattern are rounded. (d) Due to the backscattering and resist heating described above, a slight error occurs between the design size and the resist patterning size.

On the other hand, when the X-ray exposure method is used for the exposure of the resist template, the verticality of the profile of the template is further improved as compared with the electron beam exposure method. However, even in this case, the following problems are raised. (e) Since the X-ray exposure method is proximity exposure, the roundness at the corners of the pattern may be more noticeable than in the case of electron beam exposure. (f) When the dimensional accuracy of the X-ray mask pattern is not sufficient, the dimensional accuracy of the resist pattern also becomes poor. (g) Secondary electrons are generated from the substrate due to X-ray irradiation, so that the edge profile of the resist is deteriorated.

The shape accuracy of the resist mold directly reflects the shape accuracy of the aperture. Therefore, whichever of the above exposure methods is used, it is necessary to solve or mitigate the effects caused by these problems.

There are some other problems in aperture manufacturing using a thick film resist mold and a plating method. For one, when an X-ray mask is used for exposing a mold pattern, even if there is a demand for making a slight change to the pattern, it is not easy to meet this demand. This is because it takes a lot of labor and time to newly manufacture the X-ray mask, and it is not easy to modify the pattern provided on the X-ray mask.

In addition to this, abnormal growth of particles may occur during plating, and the dimensional accuracy of the aperture may deteriorate. When a large number of apertures are provided on the same aperture plate like the aperture for CP (Character Projection), the finish of some apertures may not be good. In such a case, the aperture plate as a whole cannot satisfy the desired specifications, and the yield of aperture manufacturing is reduced.

In view of this, the present invention uses a focused ion beam (FIB) when the dimensional accuracy of the aperture pattern is not sufficient in the aperture manufacturing method in which the aperture pattern is formed by a plating method using a thick film resist as a template. It is provided that the dimensional accuracy of the pattern is improved by modifying and processing the pattern.

As a method for improving the dimensional accuracy of the aperture pattern, the following complementary (aperture side and mold side) methods can be used depending on the situation. (1) When processing in a direction in which the aperture opening portion is widened (i) A pattern edge portion of a thin film provided with an aperture, for example, an Au thin film is directly sputtered by using FIB to be processed.

(Ii) Prior to plating, a thin film such as a carbon film is added to the edge portion of the template layer by applying the assisted film forming method by FIB. (2) When processing in a direction to narrow the aperture opening portion (i) Add a thin film such as an Au film by applying an assisted film formation method by FIB to a pattern edge portion of a thin film provided with an aperture, for example, an Au thin film .

(Ii) Before plating, the edge portion of the resist mold is processed by sputtering with FIB. Further, regarding the curvature of the corner portion of the pattern, which is a problem in the accuracy of the aperture, it is possible to perform processing with sufficient accuracy by making the beam diameter of the FIB smaller than the desired radius of curvature.

The technique based on the above FIB will be described with reference to each embodiment. First, a sixth embodiment will be described below. For example, the CP aperture manufacturing method by the conventional thick film resist template / Au plating method is performed.
That is, on a substrate of Si single crystal, P serving as a base for plating
Then, a film such as d is formed, and then PMMA resist is applied to a thickness of 5 μm and baked. Then, a pattern serving as a template is drawn by using electron beam exposure or X-ray exposure. The template pattern is, for example, as follows. A
The area where the u thin film is formed is set to 3 mm □, and the pattern of the portion to be the aperture is provided therein. The variable shaping aperture is a rectangular type of 200 μm □, and the CP aperture is formed by extracting a part of the pattern from the actual device pattern for line / space patterns, contact holes, etc. in consideration of the periodicity. To use.

Then, the resist is developed to form a resist mold. Next, this resist template is formed by electrolytic plating to form an Au thin film on the substrate. Then, an opening is provided in the substrate from the back surface of the substrate by using an anisotropic etching method using a KOH (potassium hydroxide) aqueous solution or the like. By depositing gold on both surfaces of the substrate, dicing it and mounting it on a holder, a second molding aperture (61) as shown in FIG. 6 is completed.

The details of the manufacturing process of the above configuration are shown in FIG.
According to the process of. However, the aperture pattern is different. Further, in the template resist, the dummy pattern may or may not be formed in the aperture-corresponding region (for example, a large rectangular region or the like) where the dummy pattern can be formed.

When it is judged that the dimensional accuracy of the manufactured aperture is not sufficient, the dimensional accuracy is improved as follows by sputtering etching using a focused ion beam (FIB) device.

FIG. 7 is a plan view showing a part of the second shaping aperture 61 manufactured as shown in FIG. An example of a method of correcting the pattern when the pattern of the manufactured aperture is finished small (solid line AP) with respect to the design pattern (broken line DP) will be described. In this case, the pattern edge portion of the Au thin film forming the aperture may be sputter-etched to widen the opening portion so as to match the design pattern (broken line DP).

The FIB conditions are as follows, for example.
Ga ⁺ is used for the ions, the acceleration voltage is 30 kV, and the beam current is 100 pA. Here, for example, if the radius of curvature of the corner portion of the pattern is desired to be 0.1 μm or less, the beam diameter is focused to 0.1 μmφ or less. Under these conditions, the aperture thin film is etched by scanning the Ga ⁺ beam in the region to be etched.

The FIB sputtering rate is
It can be roughly estimated to be several atoms / ion. Here, the sputtering rate for Au is 5 atoms /
Assume ion. In this case, the time required to etch a 50 μm × 0.4 μm region of a 4 μm-thick Au thin film while beam scanning is about 30 minutes.

By etching the edge of the aperture pattern using the FIB in this way, the pattern can be modified so that the error from the design dimension is reduced.
The radius of curvature of the corner portion of the pattern or the roughness of the pattern edge can be equal to or less than the beam size.

Next, a seventh embodiment will be described below. This corresponds to the opposite case. FIG. 8 is a plan view showing a part of the second shaping aperture 61 manufactured as shown in FIG. When the pattern of the manufactured aperture is large compared to the design pattern (dashed line DP) (solid line A
An example of the correction method of P) will be described. In this case, on the pattern edge portion of the Au thin film forming the aperture,
By additionally depositing Au, the aperture is made to match the design pattern (broken line DP). For additional film formation of Au, a beam assisted film formation method using FIB or an electron beam may be used.

To form an Au thin film by the beam assisted film forming method, for example, C ₇ H ₇ F ₆ O ₂ A is used as a film forming gas.
u is used. Using FIB, for example, 15 ke
Using a Ga ⁺ beam with V and a current density of 0.05 A / cm ² , it is possible to deposit 4 to 5 Au atoms per ion.

By the way, when the Au thin film is additionally formed to correct the pattern, it is desirable that the underlayer remains in the aperture opening portion when the pattern is corrected. Figure 2
For example, it is desirable that at least the palladium layer (plating base), the titanium layer, and the SiN layer immediately below them exist. Thus, if there is a layer of the plating base, it becomes easy to carry out the step of depositing Au on the layer. Therefore, in the manufacturing process including the process of additionally forming Au to correct the pattern, the substrate opening process using KOH (potassium hydroxide) is performed in accordance with the manufacturing process of the sixth embodiment, and the plating base layer after that is used. Regarding the removal of the SiN layer and the SiN layer, the process may be changed so that it is performed after the correction step by FIB is completed and the template layer is further removed.

Generally, the patterning accuracy is higher in etching than in assisted film formation. Therefore, in the correction by FIB of the seventh embodiment, etching may be further performed after the assisted film formation, if necessary.

Next, an eighth embodiment will be described below. As a correction method when the pattern of the manufactured aperture is small compared to the design pattern,
In addition to the correction method described in the above embodiment, by applying assisted film formation using FIB to the pattern edge portion of the resist template layer to additionally form carbon or the like,
There is a way to modify it so that it matches the design pattern.

To form a carbon thin film by the beam assisted film forming method using FIB, styrene, pyrene or the like may be used as a film forming gas. For the FIB, for example, a Ga ⁺ beam of 30 keV is used. Under this condition, 10 carbon atoms can be deposited per ion.

As described above, F was applied to the plating template layer.
By applying the beam assisted film formation by IB, the aperture portion of the aperture can be corrected in the direction of widening, and the dimensional accuracy after the correction can be made sufficiently excellent.

Incidentally, the patterning accuracy of the etching is usually higher than that of the assisted film formation. Therefore,
In the above correction, if necessary after assist film formation,
Further etching may be performed.

Next, the ninth embodiment will be described below. As a correction method when the pattern of the aperture made for the design pattern is greatly finished,
In addition to the repair method described in the seventh embodiment, there is a method of repairing the pattern edge portion of the resist template layer by sputter etching with FIB so as to match the design pattern. If the FIB condition and the scan region condition are the same as in the sixth embodiment, the time required to etch the PMMA resist having a thickness of 5 μm is about 30 minutes. This step is performed after the PMMA development and before plating. If necessary, a light RIE process may be performed after this step.

The end point of sputter etching by FIB can be monitored by using a mass spectrometer. In the above-described aperture manufacturing process, the lower layer of the resist template layer is Pd which is a base of plating. Therefore, in this case, by monitoring Pd, the time when the etching should be finished can be known.

As described above, FI was applied to the resist template.
By using the sputter etching with B, it is possible to correct the aperture of the aperture in the direction of narrowing it, and it is possible to make the dimensional accuracy after the correction sufficiently excellent.

Next, the tenth embodiment will be described below. When exposing a thick film resist, generally, the thinner the resist film, the better the verticality of the edge profile of the resist pattern. On the other hand, the Au thin film is required to have a thickness necessary to block the electron beam. For example, the transmission limit film thickness of the Au thin film for an electron beam of 50 keV is about 3.7 μm. In order to deposit 3.7 μm of Au by plating, the thickness of the mold is required to be about 4 μm.

By the way, when the film thickness of the resist template is thinner than 4 μm, for example, when it is about 2.5 μm, the film thickness is 4 μm.
The verticality of the edge profile is improved as compared with the case of m. However, the thickness of the mold with a film thickness of 2.5 μm is 3.7 μm.
When the Au thin film of m is formed, the Au thin film is formed so as to overflow the mold.

FIGS. 9A to 9C are sectional views showing a method of forming an aperture according to the tenth embodiment. When the Au thin film 16 having a thickness of 3.7 μm is formed on the resist mold 13 having a film thickness of 2.5 μm, the Au thin film 16 overhangs the mold 13 and is formed. The dimensional accuracy of the aperture is determined by the portion 161 of this overhang.

In the above example, the thickness of the overhanging portion 161 is 1.2 μm. On the other hand, since the forming accuracy of the mold is improved because the film thickness of the mold 13 is thin, the dimensional accuracy of the portion not overhanging is good (FIG. 9 (b)). Therefore, the overhung part 161
If only this is removed using the FIB, an aperture with high dimensional accuracy can be realized (FIG. 9C). According to this method, as compared with the case of a usual manufacturing method in which an Au thin film having a thickness of 3.7 μm is formed on a mold having a thickness of 4 μm and the edge portion of the Au thin film is removed by a thickness of 3.7 μm, This has the advantage that the time required for sputter etching can be reduced.

As described above, by using a method of making the resist mold film thinner than originally required and etching away the overhanging aperture layer on the mold layer by FIB after the plating step, An aperture with excellent accuracy can be easily formed.

Next, the eleventh embodiment will be described below. When the resist template pattern is exposed by the X-ray exposure method, the X-ray mask is provided with a basic pattern. This is a pattern as shown in FIG. 10, for example. After transferring this pattern to the resist,
Using the methods according to the embodiments of 10 to 10, the basic pattern is modified to have a desired shape. For example, by etching the Au thin film by the method described in the sixth embodiment, the aperture pattern can be changed into the shape as shown in FIG. Further, the shape as shown in FIG. 12 can be changed by the method described in the seventh embodiment. In addition, the method described in the eighth and ninth embodiments, that is, the method of processing the resist mold may be applied.

In this way, the X-ray mask is provided with a basic pattern, and after X-ray exposure, the plating mold or the thin film provided with the aperture can be processed into a desired shape. it can. By using this technique, it is not necessary to manufacture an X-ray mask every time the pattern is changed, which contributes to cost reduction.

Next, the twelfth embodiment will be described below. As shown in the plan view of FIG. 13, even when the aperture plate is composed of the Si thin film 131 and the substrate 132 holding the Si thin film 131, the dimensional accuracy of the aperture can be improved by correcting the pattern using the FIB. Can be improved. In this case, only the correction to widen the shape of the aperture by etching is performed. Therefore,
In order to obtain sufficient dimensional accuracy, the opening is formed in advance to have a size smaller than the desired size (solid line AP), and etching is performed by the FIB so that the desired size, that is, the design pattern (broken line DP) is obtained. The method of doing

When the Si thin film is sputter-etched by FIB, the conditions described in the sixth embodiment can be used. That is, Ga ⁺ is used for the ions, the acceleration voltage is 30 kV, the beam current is 100 pA, and the beam is focused to 0.1 μmφ or less. Then, the portion to be removed by etching is scanned with a beam. Assuming a sputter rate of 5 atoms / ion, 50 μm × 0.4 μm
The region can be etched at a speed of about 6 minutes / μm.

Next, the thirteenth embodiment will be described below. A method for improving the dimensional accuracy of the aperture pattern by etching using FIB is Pt, Ta.
It can also be applied to improve the dimensional accuracy of a conventional aperture manufactured by machining a thin metal plate such as. In this case, note the following two points.

(1) The edge of the opening portion of the aperture is tapered. (2) The aperture M is larger than the desired size by a margin M.
Just make it small. In this case, the length of the margin M is set to M ≧ D / tan θ. Here, θ is the above-mentioned taper angle, and D is the desired plate thickness (thickness sufficient to block the electron beam).

As shown in FIG. 14, the metal thin plate 141 is FI
When the pattern edge is etched with B, the margin M may be removed by etching. If the margin and the taper angle are set as in the above (2), only the minimum necessary thickness needs to be etched, and the processing becomes easy. The method paying attention to the above (1) and (2) can be applied to the fabrication of the Au aperture or Si aperture described above.

As described above, the pattern edge portion of the template layer or the aperture thin film layer is processed by using the etching method or the film forming method using FIB, so that the aperture opening portion can be widened or narrowed. Also, the aperture pattern can be modified. Further, with respect to the problem of making the curvature of the corner portion of the pattern sufficiently small, which has been difficult in the past, it is possible to obtain sufficient dimensional accuracy by making the beam diameter smaller than the desired dimensional accuracy.

Similarly, by including the processing by FIB in the manufacturing process, it becomes easy to change the shape of the aperture pattern. Therefore, when it is desired to change the shape of the aperture pattern, a new X-ray mask is manufactured. There is no need to do it. Therefore, every time the pattern is changed, X
It is possible to save the labor and time of remaking the line mask.

If a large number of apertures are provided on the same aperture plate like the aperture for character projection and some of the apertures are not finished well, they are corrected using FIB. As a result, the yield of aperture manufacturing can be improved.

FIG. 15 is a block diagram showing a main part of an electron beam exposure apparatus as a fourteenth embodiment of the present invention.
The electron beam emitted from the electron gun 151 irradiates the first shaping aperture 152. The beam that has passed through the first shaping aperture 152 and is shaped passes through the selection changer 153 to the second shaping aperture 153.
It is selectively projected onto the shaping aperture 154. The second shaping aperture 154 is a beam shaping aperture for CP + VSB. The beam thus shaped is positioned by the objective lens (reduction lens) 155 and the positioning deflector 156 and reaches a predetermined position on the sample surface (wafer) 157.

The manufacturing method of the aperture as described in the sixth to twelfth embodiments is appropriately applied to each of the first shaping apertures 152 and the second shaping apertures 153 in the above LSI manufacturing apparatus. As a result, it is possible to provide a higher-precision LSI manufacturing apparatus and expand the range of application of drawing patterns. This is effective in manufacturing a versatile aperture such as an ASIC.

[0104]

As described above, according to the present invention,
Focusing on that the shape accuracy of the mold for forming the aperture is directly reflected on the shape accuracy of the aperture, and satisfying various manufacturing conditions, a highly accurate aperture can be manufactured. Also, when manufacturing an aperture with a mold, FI
By including the step of correction by B, the dimensional accuracy of the aperture pattern can be easily improved. Further, it is possible to significantly improve the dimensional accuracy of an inexpensive aperture manufactured by machining a thin metal plate. As a result, the yield of aperture manufacturing can be improved, which contributes to cost reduction, improves the accuracy of the LSI manufacturing apparatus, and expands the range of application of drawing patterns.

[Brief description of drawings]

1A and 1B are respectively a plan view and a sectional projection view showing a step in the process which is a feature of a method of manufacturing a beam shaping aperture according to a first embodiment of the present invention.

2A to 2E are cross-sectional views showing a method of manufacturing the aperture described in FIG. 1 in process order.

3 (a) and 3 (b) relate to a second embodiment of the present invention, and the dimensional accuracy of the mold pattern when the distance ΔL between the edge of the mold pattern and the edge of the dummy pattern in FIG. 1 is changed. FIG.

FIG. 4 is a PMM relating to third and fourth embodiments of the present invention.
The characteristic view explaining the forward scattering radius of the electron beam in A resist.

FIG. 5 is a configuration diagram showing a main part of an electron beam exposure apparatus according to a fifth embodiment of the present invention.

FIG. 6 is an Au thin film and S according to a sixth embodiment of the present invention.
FIG. 3 is a projection diagram illustrating a configuration of a beam shaping aperture having a configuration of an i substrate.

FIG. 7 shows a sixth and an eighth embodiments of the present invention.
FIG.

FIG. 8 relates to the seventh and ninth embodiments of the present invention.
FIG.

9 (a) to 9 (c) are each a tenth embodiment of the present invention.
6A to 6C are cross-sectional views showing a method for creating an aperture relating to the embodiment of FIG.

FIG. 10 is a plan view showing a part of a basic pattern in an X-ray mask according to the eleventh embodiment of the present invention.

FIG. 11 shows an eleventh embodiment of the invention.
The 1st top view which changed the shape of the aperture pattern created by the basic pattern of.

FIG. 12 shows an eleventh embodiment of the invention.
FIG. 5 is a second plan view in which the shape of the aperture pattern created by the basic pattern of FIG.

FIG. 13 is a plan view showing an aperture composed of a Si thin film and a substrate holding the Si thin film according to a twelfth embodiment of the present invention.

FIG. 14 is a sectional view of an aperture made by machining a thin metal plate according to a thirteenth embodiment of the present invention.

FIG. 15 is a configuration diagram showing a main part of an electron beam exposure apparatus according to a fourteenth embodiment of the present invention.

16 (a) and 16 (b) are respectively a plan view and a cross-sectional view showing a configuration of a typical aperture.

17 (a) and 17 (b) are respectively a plan view and a cross-sectional view showing the structure of a conventional resist mold for forming an aperture.

[Explanation of symbols]

11, 132 ... Substrate 12 ... Plating base 13 ... Mold (resist mold) 14 ... Island pattern (mold pattern) 15 ... Nested pattern (dummy pattern) 16 ... Au thin film, 17 ... Photoresist 51, 151 ... Electron Gun 52 ... Condenser lenses 53, 152 ... First shaping aperture 54 ... Projection lens 55 ... Molding deflector 56 ... Second shaping aperture 57 ... Sub deflector 58 ... Objective lens 59 ... Main deflector 60, 157 ... Sample surface (wafer ) 61,154 ... Beam shaping aperture for CP + VSB (second shaping aperture) 131 ... Si thin film 141 ... Metal thin plate 153 ... Selective deflector 155 ... Objective lens (reducing lens) 156 ... Positioning deflector

─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Toru Koike 1 Komukai Toshiba Town, Saiwai-ku, Kawasaki City, Kanagawa Prefecture Toshiba Research and Development Center (72) Inventor Susumu Oki Komukai Toshiba-cho, Kawasaki City, Kanagawa Prefecture No. 1 in Toshiba R & D Center Co., Ltd. (72) Inventor Yoshimitsu Kato Komukai-cho, Komukai-ku, Kawasaki-shi, Kanagawa No. 1 In Toshiba R & D Center (72) Inventor Tadahiro Takigawa Komukai, Sachi-ku, Kawasaki-shi, Kanagawa Toshiba Town No. 1 in Toshiba Research & Development Center Co., Ltd. (56) Reference JP-A-7-78748 (JP, A) JP-A 1-216529 (JP, A) JP-A 63-211620 (JP, A) Special Kaihei 1-15922 (JP, A) JP 62-147731 (JP, A) JP 6-5497 (JP, A) JP 2-310913 (JP, A) (58) Fields investigated ( Int.Cl. ⁷ , DB name) H01L 21/027 C25D 1/20

Claims (10)

(57) [Claims] 1. A method of manufacturing an aperture including a step of forming a mold on a substrate and forming a thin film by a plating method,
Regarding the island-shaped pattern on the mold side corresponding to the side wall of the aperture forming part, a step of forming a mold having a nested pattern with a side wall inside, and forming a metal film on the substrate in the mold A method of manufacturing an aperture, comprising: a step of removing the template; and a step of etching a predetermined region from the back surface of the substrate on which the metal film is formed to form an opening. 2. A mold for making an aperture, which has an island-shaped mold pattern corresponding to a side wall of an aperture forming portion, and has a pattern with a side wall inside the mold pattern. 3. A mold for making an aperture, wherein an island-shaped mold pattern corresponding to a side wall of an aperture forming portion has a nested pattern with a side wall inside the mold pattern. 4. When forming an island-shaped mold pattern corresponding to the side wall of the aperture forming portion on a plate, a nested pattern with a side wall is simultaneously formed inside the island-shaped mold pattern by electron beam exposure. A step of manufacturing an aperture, comprising a step of making a distance between an edge of the island-shaped pattern and an edge of the nested pattern longer than a radius of backscattering from the substrate by the electron beam. Mold manufacturing method. 5. When forming an island-shaped mold pattern corresponding to a side wall of an aperture forming portion on a plate by electron beam exposure, a nested pattern accompanied by a side wall is simultaneously formed inside the island-shaped mold pattern. A step of forming by beam exposure, wherein an acceleration voltage of the electron beam is equal to or larger than an acceleration voltage of an electron beam used in an LSI manufacturing apparatus using the aperture,
And a method of manufacturing a mold for making an aperture, characterized in that the distance between the edge of the island-shaped pattern and the edge of the nested pattern is made longer than the radius of backscattering from the substrate by the electron beam. . 6. When forming an island-shaped mold pattern corresponding to a side wall of an aperture forming portion on a plate, a step of simultaneously forming a nested pattern with a side wall inside the island-shaped mold pattern is included. , The aperture has an acceleration voltage of 50
A method of manufacturing a mold for manufacturing an aperture, wherein the mold pattern is formed by an X-ray exposure method so as to be used in an LSI manufacturing apparatus that handles an electron beam exceeding kV. 7. An LS for treating a charged particle beam or energy beam, including a step of forming a mold on a substrate and forming a thin film having a plurality of aperture patterns by a plating method.
I In manufacturing an aperture for a manufacturing apparatus, by forming a plating thin film thicker than the layer thickness of the mold, the portion overhanging on the upper surface of the mold is
A method of manufacturing an aperture, comprising a step of removing by etching using IB. 8. In manufacturing an aperture for a charged particle beam exposure apparatus, an aperture pattern is first formed to have a size smaller than a desired size, and then an edge portion of the aperture pattern is removed by etching using an FIB to form an opening portion. A method of manufacturing an aperture, comprising the step of modifying the aperture pattern so as to have a desired opening size by expanding the aperture. 9. In manufacturing an aperture for a charged particle beam exposure apparatus, the thickness of a thin film or thin plate including an aperture pattern is first formed thicker than a thickness D required for exposure, and the size of an aperture opening. So as to be smaller than a desired dimension, a margin portion having a length M is provided at the edge portion of the aperture pattern, and the edge profile of the aperture pattern is tapered by a taper angle θ.
Is formed in a tapered shape, and then the margin portion is etched and removed so that the opening portion as the aperture has a desired size, and the length M of the margin portion of the aperture pattern is , The taper angle θ, and the thickness D required above,
A method of manufacturing an aperture, characterized in that a relationship of M ≧ D / tan θ is established. 10. The method of manufacturing an aperture according to claim 2, wherein X-ray exposure is used for patterning the template used in the plating method, and at this time, the X-ray mask for transferring the template pattern is basically used. A desired pattern is obtained by applying the aperture pattern correction step to the mold after transferring the pattern or to the thin film layer on which the aperture after plating is formed after transferring the pattern. A method for manufacturing an aperture characterized by the following.