JP2004087817A - Micromachining method of substrate - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for micromachining a substrate by using a magnetic pattern. <P>SOLUTION: The micromachining method of the substrate includes each step for forming a magnetic film on the substrate, adding a desired magnetic pattern to the magnetic film, sprinkling magnetic powder onto the magnetic film where the magnetic pattern is given, selectively concentrating the magnetic powder according to the magnetic pattern, and performing reactive ion etching with the centrally arranged magnetic powder as a mask. The magnetic pattern is made, for example, by using a magnetic head that is modulated according to the data to be written while rotating the substrate. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a method for finely processing a substrate such as a semiconductor substrate.
[0002]
[Prior art]
In general, in semiconductor processing, a photoresist applied to a semiconductor substrate is exposed to a pattern through a photomask, developed and removed to remove unnecessary portions of the photoresist, and a fine processing method is performed by etching using the photoresist mask.
[0003]
There are two types of etching, wet etching and dry etching. However, since wet etching has a problem that processing accuracy is lowered due to undercut or the like, dry etching such as reactive ion etching (RIE) is frequently used recently.
[0004]
The pattern is exposed using ultraviolet light having a short wavelength such as a G line or an I line, or a KrF laser, an ArF laser, or the like. Since a high-precision optical system such as a stepper is required for pattern exposure, there is a problem that the cost increases as the line width becomes finer.
[0005]
[Problems to be solved by the invention]
As described above, in a normal semiconductor manufacturing process using photoresist and photolithography, the line width in ultraviolet exposure is limited to about 0.1 μm, and electron beam exposure apparatuses and the like have been studied to further reduce the line width. ing.
[0006]
However, the electron beam exposure apparatus requires development of many new technologies such as a mask necessary for a circuit printing process, and may be extremely expensive.
[0007]
Therefore, an object of the present invention is to provide a method for finely processing a substrate using a magnetic powder as a mask.
[0008]
[Means for Solving the Problems]
According to one aspect of the present invention, a magnetic film is formed on a substrate, a desired magnetic pattern is provided on the magnetic film, and magnetic powder is sprinkled on the magnetic film provided with the magnetic pattern, and the magnetic powder is A fine processing method for a substrate, characterized in that reactive ion etching is performed by using the magnetic powder, which is selectively concentrated according to the magnetic pattern, as a mask, as a mask.
[0009]
Since the minimum width of the magnetic pattern of the magnetic disk drive is about 0.05 μm in the current technology, a fine pattern can be relatively easily patterned using a magnetic head.
[0010]
By performing the reactive ion etching using the magnetic powder as a mask due to the selective arrangement of the magnetic powder attached to the magnetic film, a very fine groove can be formed in the substrate 2 in an arbitrary pattern.
[0011]
According to another aspect of the present invention, a magnetic film is formed on a substrate, a desired magnetic pattern is applied to the magnetic film, and a magnetic fluid containing magnetic powder is applied to the magnetic film provided with the magnetic pattern. A substrate, wherein the magnetic powder is selectively concentrated according to the magnetic pattern, the magnetic fluid is dried, and reactive ion etching is performed using the concentrated magnetic powder as a mask. Is provided.
[0012]
Preferably, the application of the magnetic pattern is performed using a magnetic head modulated according to data to be written while rotating the substrate. Alternatively, the magnetic film is a perpendicular magnetization film, and the application of the magnetic pattern is performed by irradiating the magnetic film with a laser beam modulated according to data to be written while applying a predetermined magnetic field. Alternatively, the irradiation can be performed using a coil modulated in accordance with data to be written while irradiating the magnetic film with a laser beam having a constant power.
[0013]
According to still another aspect of the present invention, a magnetic fluid containing a first magnetic powder is applied to a substrate, the applied magnetic fluid is dried, and the first magnetic powder is attached to a substrate, A first magnetic powder is provided with a desired magnetic pattern, a second magnetic powder is sprinkled on the first magnetic powder provided with the magnetic pattern, and the second magnetic powder is selectively concentrated according to the magnetic pattern. And performing reactive ion etching using the second magnetic powders arranged as a mask as a mask.
[0014]
According to still another aspect of the present invention, a photoresist containing a magnetic powder is applied on a substrate, the applied photoresist is dried, a desired magnetic pattern is applied to the photoresist, and a magnetic pattern is applied. The magnetic powder is dropped on the exposed photoresist, the magnetic powder is selectively concentrated according to the magnetic pattern, and exposure and development are performed, so that a portion of the photoresist that is not covered with the magnetic powder is exposed. A resist is removed, and reactive ion etching is performed using the magnetic powder arranged as a mask as a mask.
[0015]
BEST MODE FOR CARRYING OUT THE INVENTION
First, a microfabrication method of a substrate according to a first embodiment of the present invention will be described with reference to FIGS. 1 (A) and 1 (B). First, as shown in FIG. 1A, a magnetic film 4 such as a Co alloy magnetic film is formed on a substrate 2 such as a semiconductor substrate. The magnetic film 4 is an in-plane magnetized film, and a known method such as sputtering can be used for forming the magnetic film 4.
[0016]
Next, as shown in FIG. 1B, a desired magnetic pattern 6 is applied to the magnetic film 4. The application of the magnetic pattern 6 can be performed using a magnetic head for a magnetic disk drive.
[0017]
Referring to FIG. 3, a schematic diagram of magnetic patterning using the magnetic head 18 is shown. While rotating the substrate 2 in the direction of arrow 16 by the spindle motor 14, the magnetic pattern 6 is written on the magnetic film 4 by the magnetic head 18 modulated according to the data to be written.
[0018]
Since the minimum width of a magnetic pattern (recording mark) of a magnetic disk device is about 0.05 μm in the current technology, a fine magnetic pattern can be relatively easily patterned using a magnetic disk magnetic head.
[0019]
Next, when the magnetic powder 8 is sprinkled on the magnetic film 4, the magnetic powder 8 is selectively concentrated according to the magnetic pattern 6 as shown in FIG. That is, as shown in FIG. 2, since the magnetic force lines 12 are concentrated most at the boundary between the adjacent magnetic patterns 6, the magnetic powder 8 is intensively arranged at this portion.
[0020]
Next, when reactive ion etching (RIE) is performed using the magnetic powders 8 arranged as a mask as a mask, the selectivity can be given to RIE depending on the presence or absence of the magnetic powders 8. As shown, a groove 10 having a very small line width can be formed in the substrate 2.
[0021]
FIG. 4 is a view showing the concentrated arrangement of magnetic powder when the perpendicular magnetization film 4 ′ is formed on the substrate 2. The perpendicular magnetization film 4 ′ is, for example, a magneto-optical recording film, and is magnetized in the vertical direction as indicated by reference numeral 20. That is, the magnetic pattern 20 is oriented in the vertical direction.
[0022]
Also in the case of the perpendicular magnetization film 4 ′, since the magnetic force lines 22 are concentrated on the interface between the adjacent magnetic patterns 20, the magnetic powder 24 is concentrated on the interface between the adjacent magnetic patterns 20.
[0023]
FIG. 5 schematically shows how the magnetic patterning is performed on the magneto-optical recording film. On the substrate 2, a magneto-optical recording film 26 having perpendicular magnetic anisotropy is formed.
[0024]
A mirror 34 reflects a laser beam 28 modulated in accordance with data to be written while applying a predetermined magnetic field 36 with a magnet 34, and then focuses the laser beam 28 on the magneto-optical recording film 26 with an objective lens 32. A perpendicular magnetic pattern can be written on the magneto-optical recording film 26.
[0025]
FIG. 6 schematically shows how magnetic patterning is performed on a magneto-optical recording film by a magneto-optical disk device of a magnetic field modulation recording system. A coil 40 for generating a magnetic field is formed on the lower surface of the glass substrate 38, and a hemispherical lens 42 is bonded to the upper surface of the glass substrate 38.
[0026]
After the laser beam 28 ′ having a constant power is reflected by the mirror 30, it is focused on the magneto-optical recording film 26 by the hemispherical lens 42. Then, the current flowing through the coil 40 is modulated according to the data to be written, and a perpendicular magnetic pattern is written on the magneto-optical recording film 26 by the modulated magnetic field.
[0027]
Next, with reference to FIGS. 7A to 7D, a method for finely processing a substrate according to the second embodiment of the present invention will be described. The step of forming the magnetic film 4 in FIG. 7A and the step of providing a magnetic pattern in FIG. 7B are the same as those in the first embodiment.
[0028]
In this embodiment, after the magnetic pattern providing step shown in FIG. 7B, a magnetic fluid containing magnetic powder is applied on the magnetic film 4 provided with the magnetic pattern as shown in FIG. 7C. Then, the magnetic powder 44 is selectively concentrated according to the magnetic pattern 6.
[0029]
As the magnetic fluid, a liquid obtained by dissolving magnetic powder on a colloid in a resin solution containing a volatile solvent can be employed. Next, the magnetic fluid is dried, and the magnetic powder 44 is selectively and intensively attached to the magnetic film 4 according to the magnetic pattern 6.
[0030]
Next, when reactive ion etching (RIE) is performed using the magnetic powders 44 arranged as a mask as a mask, fine grooves 10 are formed in the substrate 2 by the selectivity of RIE as shown in FIG. it can.
[0031]
FIGS. 8A to 8D show a fine processing method for a substrate according to a third embodiment of the present invention. First, as shown in FIG. 8A, a magnetic fluid 46 containing a first magnetic powder 45 is applied on the substrate 2, the applied magnetic fluid 46 is dried, and the first magnetic powder 46 is applied on the substrate 2. 45 is deposited. As the magnetic fluid, a liquid obtained by dissolving magnetic powder on a colloid in a resin solution containing a volatile solvent can be employed.
[0032]
Next, as shown in FIG. 8B, a desired magnetic pattern 6 is applied to the first magnetic powder 45. The application of the magnetic pattern 6 is performed using, for example, a magnetic head, as in the first and second embodiments.
[0033]
Next, as shown in FIG. 8C, the second magnetic powder 8 is sprinkled on the first magnetic powder 45 provided with the magnetic pattern 6, and the second magnetic powder 8 is selectively applied according to the magnetic pattern 6. Focus.
[0034]
Next, when reactive ion etching (RIE) is performed using the second magnetic powder 8 arranged as a mask as a mask, fine grooves 10 are formed in the substrate 2 by RIE selective etching as shown in FIG. can do.
[0035]
Next, a method for finely processing a substrate according to a fourth embodiment of the present invention will be described with reference to FIGS. First, as shown in FIG. 9A, a photoresist 48 containing magnetic powder is applied on the substrate 2 and baked at a predetermined temperature to dry the photoresist 48.
[0036]
Next, as shown in FIG. 9B, a desired magnetic pattern 6 is applied to the photoresist 48 using the magnetic head 18 shown in FIG. When the magnetic powder 8 is sprinkled on the photoresist 48 provided with the magnetic pattern 6 as described above, the magnetic powder 8 is selectively concentrated according to the magnetic pattern 6 as shown in FIG. Placed on top.
[0037]
Next, the photoresist 48 is exposed and developed using the magnetic powder 8 arranged as a mask as a mask, and the exposed portion of the photoresist 48 is removed as shown in FIG. 9D.
[0038]
Next, when reactive ion etching (RIE) is performed using the magnetic powder 8 arranged as a mask as a mask, fine grooves 10 can be formed in the substrate 2 as shown in FIG.
[0039]
Next, a method of magnetically transferring a magnetic film to a magnetic medium using a substrate provided with a desired magnetic pattern on a magnetic film as a master substrate is described. First, as shown in FIG. 10A, a magnetic medium (magnetic disk) 52 is initialized by applying a magnetic field P in a predetermined direction by a magnet.
[0040]
Next, using the substrate 2 having the desired magnetic pattern 6 on the magnetic film 4 shown in FIG. 1B as a master substrate, the master substrate 2 is superimposed on the magnetic medium 52, and the magnet 54 opposes the magnetic field P during initialization. The magnetic pattern 52 on the master substrate 2 is transferred to the magnetic medium 52 by rotating the magnetic medium 52 in the direction of arrow R while applying the magnetic field Q in the direction. Thereby, the magnetic medium 52 having the magnetic pattern transferred magnetically as shown in FIG. 10C is completed.
[0041]
The present invention includes the following supplementary notes.
[0042]
(Supplementary Note 1) A magnetic film is formed on a substrate,
Giving a desired magnetic pattern to the magnetic film,
Sprinkling magnetic powder on the magnetic film provided with a magnetic pattern, selectively concentrate the magnetic powder according to the magnetic pattern,
Performing reactive ion etching using the magnetic powder arranged as a mask as a mask,
A microfabrication method for a substrate, comprising:
[0043]
(Supplementary Note 2) The substrate fine processing method according to Supplementary Note 1, wherein the application of the magnetic pattern is performed using a magnetic head modulated in accordance with data to be written while rotating the substrate.
[0044]
(Supplementary Note 3) The magnetic film is a perpendicular magnetization film,
2. The method according to claim 1, wherein the application of the magnetic pattern is performed by irradiating the magnetic film with a laser beam modulated according to data to be written while applying a predetermined magnetic field. .
[0045]
(Supplementary Note 4) The magnetic film is a perpendicular magnetization film,
2. The method according to claim 1, wherein the application of the magnetic pattern is performed by irradiating the magnetic film with a laser beam having a constant power and using a coil modulated in accordance with data to be written.
[0046]
(Supplementary Note 5) A magnetic film is formed on the substrate,
Giving a desired magnetic pattern to the magnetic film,
A magnetic fluid containing a magnetic powder is applied on the magnetic film provided with a magnetic pattern, and the magnetic powder is selectively concentrated according to the magnetic pattern.
Drying the magnetic fluid,
Performing reactive ion etching using the magnetic powder arranged as a mask as a mask,
A microfabrication method for a substrate, comprising:
[0047]
(Supplementary Note 6) The method for fine processing a substrate according to Supplementary Note 5, wherein the application of the magnetic pattern is performed using a magnetic head modulated according to data to be written while rotating the substrate.
[0048]
(Supplementary Note 7) The magnetic film is a perpendicular magnetization film,
6. The method according to claim 5, wherein the application of the magnetic pattern is performed by irradiating the magnetic film with a laser beam modulated in accordance with data to be written while applying a predetermined magnetic field. .
[0049]
(Supplementary Note 8) The magnetic film is a perpendicular magnetization film,
6. The method according to claim 5, wherein the application of the magnetic pattern is performed by irradiating the magnetic film with a laser beam having a constant power and using a coil modulated in accordance with data to be written.
[0050]
(Supplementary Note 9) A magnetic fluid containing the first magnetic powder is applied on the substrate,
Drying the applied magnetic fluid, causing the first magnetic powder to adhere to a substrate,
Imparting a desired magnetic pattern to the first magnetic powder;
Sprinkling a second magnetic powder on the first magnetic powder provided with a magnetic pattern, and selectively concentrating the second magnetic powder according to the magnetic pattern;
Performing reactive ion etching using the second magnetic powder, which is centrally arranged, as a mask;
A microfabrication method for a substrate, comprising:
[0051]
(Supplementary Note 10) The microfabrication method for a substrate according to supplementary note 9, wherein the application of the magnetic pattern is performed using a magnetic head modulated in accordance with data to be written while rotating the substrate.
[0052]
(Supplementary Note 11) A photoresist containing magnetic powder is applied on the substrate,
Drying the applied photoresist,
Imparting a desired magnetic pattern to the photoresist,
Dropping the magnetic powder on the photoresist provided with the magnetic pattern, selectively concentrate the magnetic powder according to the magnetic pattern,
By performing exposure and development, to remove the photoresist of the portion not covered with the magnetic powder,
Performing reactive ion etching using the magnetic powder arranged as a mask as a mask,
A microfabrication method for a substrate, comprising:
[0053]
(Supplementary Note 12) The method for fine processing a substrate according to Supplementary Note 11, wherein the application of the magnetic pattern is performed using a magnetic head modulated according to data to be written while rotating the substrate.
[0054]
【The invention's effect】
According to the present invention, as described in detail above, fine etching of a substrate can be performed relatively easily by performing reactive ion etching using magnetic powder selectively concentrated in a magnetic pattern as a mask.
[Brief description of the drawings]
FIGS. 1A to 1D are views showing a microfabrication method of a substrate according to a first embodiment of the present invention.
FIG. 2 is a diagram showing a concentrated arrangement of magnetic powder when the magnetic film is an in-plane magnetized film.
FIG. 3 is a schematic diagram of patterning using a magnetic head.
FIG. 4 is a diagram showing a concentrated arrangement of magnetic powder when the magnetic film is a perpendicular magnetization film.
FIG. 5 is a schematic diagram of magnetic patterning using a magneto-optical disk device of a light modulation recording system.
FIG. 6 is a schematic diagram of magnetic patterning using a magneto-optical disk device of a magnetic field modulation recording system.
FIGS. 7A to 7D are views showing a fine processing method for a substrate according to a second embodiment of the present invention.
8 (A) to 8 (D) are views showing a method for microfabrication of a substrate according to a third embodiment of the present invention.
FIGS. 9A to 9E are diagrams showing a fine processing method for a substrate according to a fourth embodiment of the present invention.
FIGS. 10A to 10C are views for explaining a magnetic transfer method.
[Explanation of symbols]
2 Substrate 4 Magnetic film 6 Magnetic pattern 8 Magnetic powder 10 Groove (etched part)
12 magnetic field lines 18 magnetic head 20 magnetic pattern 24 magnetic powder 26 magneto-optical recording film

Claims (5)

Form a magnetic film on the substrate,
Giving a desired magnetic pattern to the magnetic film,
Sprinkling magnetic powder on the magnetic film provided with a magnetic pattern, selectively concentrate the magnetic powder according to the magnetic pattern,
Performing reactive ion etching using the magnetic powder arranged as a mask as a mask,
A microfabrication method for a substrate, comprising: Form a magnetic film on the substrate,
Giving a desired magnetic pattern to the magnetic film,
A magnetic fluid containing a magnetic powder is applied on the magnetic film provided with a magnetic pattern, and the magnetic powder is selectively concentrated according to the magnetic pattern.
Drying the magnetic fluid,
Performing reactive ion etching using the magnetic powder arranged as a mask as a mask,
A microfabrication method for a substrate, comprising: Applying a magnetic fluid containing the first magnetic powder on the substrate,
Drying the applied magnetic fluid, causing the first magnetic powder to adhere to a substrate,
Imparting a desired magnetic pattern to the first magnetic powder;
Sprinkling a second magnetic powder on the first magnetic powder provided with a magnetic pattern, and selectively concentrating the second magnetic powder according to the magnetic pattern;
Performing reactive ion etching using the second magnetic powder, which is centrally arranged, as a mask;
A microfabrication method for a substrate, comprising: Apply a photoresist containing magnetic powder on the substrate,
Drying the applied photoresist,
Imparting a desired magnetic pattern to the photoresist,
Dropping the magnetic powder on the photoresist provided with the magnetic pattern, selectively concentrate the magnetic powder according to the magnetic pattern,
By performing exposure and development, to remove the photoresist of the portion not covered with the magnetic powder,
Performing reactive ion etching using the magnetic powder arranged as a mask as a mask,
A microfabrication method for a substrate, comprising: 5. The method according to claim 1, wherein the application of the magnetic pattern is performed using a magnetic head modulated according to data to be written while rotating the substrate.

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