JP2002184015A - Information-recording and reproducing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve the problem of the practical use of a super high density information recording and reproducing device, such as the very high price of the information-recording and reproducing device, using a near-field optical head. SOLUTION: This information-recording and reproducing device using the near-field light, is constituted of a recording medium, a light source, the near- field optical head having an opening on the side of the recording medium, a distance control mechanism which controls the distance between the near-field optical head and the recording medium, a light guide structure which guides a luminous flux, from the light source to the near-field optical head and a photodetector. Therein, the near-field optical head is constituted by at least one bob-shaped projecting part which transmits light of a desired wavelength, a light-shielding film which covers at least the bob-shaped projecting part and an opening which is formed on the tip of the bob-shaped projecting part, by simultaneously applying a force to the bob-shaped projecting part and an opening control part which has the height nearly equal to the bob-shaped protrusion part by using a pressing body having nearly a flat surface.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an information recording / reproducing apparatus for recording / reproducing information on a recording medium by utilizing the interaction of near-field light.

[0002]

2. Description of the Related Art An information recording / reproducing apparatus using light has been evolving toward a larger capacity and a smaller size. Therefore, a higher density of recording bits is required. As a countermeasure, research using a blue-violet semiconductor laser has been carried out, but with this technology, improvement of only several times the current recording density can be expected due to the problem of the diffraction limit of light. On the other hand, an information recording / reproducing method using near-field light is expected as a technique for handling optical information in a minute area exceeding the diffraction limit of light.

This technique utilizes near-field light generated by the interaction between a minute area and an optical aperture having a size equal to or smaller than the wavelength of light formed in a near-field optical head. As a result, it becomes possible to handle optical information in a region where the wavelength is equal to or less than the wavelength of light, which has been a limit in a conventional optical system, and it is expected that the density of an optical memory will be increased. Briefly, the principle of reproduction is introduced. In a method generally called a collection mode, first, light is irradiated to the surface of a recording medium, so that near-field light is localized around the recording medium according to the structure of the minute mark. The near-field light and the minute aperture are optically interacted with each other to be converted into scattered light and detected through the aperture, thereby enabling data reproduction. In a method called an illumination mode, near-field light is generated around a small aperture by irradiating light to the small aperture. The near-field light is made to approach the surface of the recording medium, and interacts with minute optical information recorded on the surface of the recording medium. Therefore, the light can be reproduced by detecting the scattered light with a light receiving element provided separately. Further, as a method of recording information, near-field light generated from a minute aperture is irradiated on the surface of the recording medium to change the shape of a minute area on the recording medium (heat mode recording) or to refract the minute area. This is performed by changing the transmittance or transmittance (photon mode recording). By using such a near-field optical head having an optical minute aperture exceeding the diffraction limit of light, it is possible to achieve a higher density of recording bits than a conventional optical information recording / reproducing apparatus.

When manufacturing a near-field optical head for recording and reproducing such optical information, formation of a minute aperture which directly affects resolution and signal SN is an important step. As one of the methods for forming a minute opening, a method disclosed in Japanese Patent Application Laid-Open No. Hei 5-21201 is known. In this method of forming an aperture, the light-shielding film at the tip is plastically deformed by pressing the sharp light guide on which the light-shielding film is deposited onto a hard flat plate with a very small pressing amount that is well controlled by a piezoelectric actuator.

Another method of forming an opening is disclosed in
There is a method disclosed in 11-265520. In this method, the opening is formed by irradiating a FIB (Focused Ion Beam) from the side to the vicinity of the tip of the light-shielding film covering the projection, and removing the light-shielding film at the tip of the projection.

[0006]

However, according to the method disclosed in Japanese Patent Application Laid-Open No. Hei 5-21201, an aperture can be formed only by one light guide. In addition, the moving resolution is several nm
Since the pushing amount needs to be controlled by the piezoelectric actuator, the opening forming apparatus must be placed in an environment where the influence of vibrations such as other devices and air is small. Further, it takes time to adjust the light propagating rod so that the rod is perpendicular to the flat plate. In addition to the piezoelectric actuator having a small moving amount, a mechanical translation table having a large moving amount is required. Further, a control device is required to control the amount of depression by using a piezoelectric actuator having a small moving resolution, and it takes several minutes to control and form the opening. Therefore, a large-scale device such as a high-voltage power supply and a feedback circuit is required to form the opening. In addition, there was a problem that the cost required for forming the openings was increased.

According to the method disclosed in Japanese Patent Application Laid-Open No. H11-265520,
Although the processing target is a projection on a flat plate, since the opening is formed using the FIB, the time required for forming one opening is 10%.
Minutes and long. Also, in order to use FIB, the sample must be placed in a vacuum. Therefore, there is a problem that the production cost for producing the opening is increased.

Furthermore, the price of an information recording / reproducing apparatus using such a near-field optical head is extremely high, and there is a problem in practical use of an information recording / reproducing apparatus having a very high density.

[0009]

In order to solve the above-mentioned problems, a first information recording / reproducing apparatus according to the present invention comprises a recording medium, a light source, and a near-field optical head having an opening on the recording medium side. A distance control mechanism for controlling a distance between the near-field optical head and the recording medium; a light guide structure for guiding a light beam from the light source to the near-field optical head; and a light receiving unit. In an information recording / reproducing apparatus for recording or reproducing information using field light, the near-field optical head includes at least one cone-shaped projection transmitting a desired wavelength, and a light-shielding film covering at least the cone-shaped projection. And a push-in body having a substantially flat surface formed at the tip of the weight-shaped protrusion by simultaneously applying a force to the weight-shaped protrusion and an opening controller having substantially the same height as the weight-shaped protrusion. Consisting of openings and It has been.

According to the present invention, in the near-field optical head used in the information recording / reproducing apparatus, the displacement amount of the plate as the push body can be reduced by providing the aperture control section near the conical projection. Even without using an actuator having a high resolution, it is easy to form a minute opening having a uniform size at the tip of the weight-shaped protrusion, and an information recording / reproducing apparatus with a very high density can be realized.

Further, since the height of the cone-shaped projection and the height of the aperture control section are always controlled to be the same, the production yield of the aperture of the near-field optical head is improved, and the quality of the information recording / reproducing apparatus is stabilized.

Further, since the near-field optical head can be formed by a photolithography process, a plurality of near-field optical heads can be formed on a sample having a large area such as a wafer. An opening having a uniform opening size can be formed for each of the created works. Further, since it is very easy to change the magnitude of the force F, it is possible to individually form openings having different opening sizes for a plurality of workpieces. In addition, since the opening is formed by simply applying the force F,
The time required to create the opening is very short, from several seconds to several tens of seconds.
Therefore, a large number of near-field optical heads can be produced at a low price, and the information recording / reproducing apparatus can be made at a very low price.

Further, since the process of forming the opening does not depend on the processing atmosphere, the processing can be performed in the atmosphere, and the processing state can be immediately observed with an optical microscope or the like. Further, by processing in a scanning electron microscope, it is possible to observe the processing state at a higher resolution than in an optical microscope. Further, by processing in a liquid, the liquid functions as a damper, so that processing conditions with further improved controllability can be obtained. Therefore, the accuracy of the aperture size of the near-field optical head is improved, and variations between devices are reduced, and stable recording and reproduction can be performed.

Further, by applying a force F to a sample on which a plurality of workpieces have been prepared, a plurality of openings having a uniform opening size can be prepared at once. In the case of processing all at once, the processing time per opening is extremely short, several hundred milliseconds or less, depending on the number of workpieces per wafer. Therefore, mass production of the near-field optical head used for the information recording / reproducing apparatus is possible, and the cost can be reduced.

Further, around the opening of the near-field optical head,
Since the light-shielding film near the tip of the cone-shaped protrusion is plastically deformed by being placed on the plate, the thickness of the light-shielding film near the opening is thick and strong. Therefore, the light blocking ratio in the vicinity of the opening is improved, and when recording information on the recording medium, the edges of the recording marks are clearly recorded, thereby improving the SN of information reproduction from the recording medium on which the information is recorded. it can. Also,
Since the strength of the opening is increased, the service life can be improved by increasing the impact resistance and the abrasion resistance.

In order to solve the above-mentioned problems, a second information recording / reproducing apparatus according to the present invention comprises a recording medium, a light source,
A near-field optical head having an opening on the recording medium side, a distance control mechanism for controlling a distance between the near-field optical head and the recording medium, and a light guide structure for guiding a light beam from the light source to the near-field optical head An information recording / reproducing apparatus configured to record or reproduce information using near-field light, comprising: a light-receiving unit; and an aperture forming mechanism. Three weight-shaped protrusions, a light-shielding film covering at least the weight-shaped protrusions, and an opening control unit having substantially the same height as the weight-shaped protrusions and the weight-shaped protrusions by using a pressing body having a substantially flat surface. At the same time, an opening is formed at the tip of the weight-shaped projection by applying a force, and the opening forming mechanism is formed of a light shielding film forming portion and an opening forming portion.

According to the present invention, in addition to the effects of the first information recording / reproducing apparatus according to the present invention, the opening of the normal near-field optical head is damaged for some reason, and the reproduction of data recorded on the recording medium can be performed. Even when data cannot be recorded, the opening of the near-field optical head can be created again to record and reproduce data. Even in the situation where the aperture of the near-field optical head is damaged once and the data recorded so far cannot be reproduced, and important data is lost, not only the reproduction of the recorded information but also the recording medium It is also possible to record information on the information recording / reproducing apparatus, and the reliability of the information recording / reproducing apparatus is dramatically improved. In addition, MO and DVD-RAM
When the information recording / reproducing device uses a structure that can replace the recording medium such as this, the life of the device can be drastically extended, and the effect of extending the life of the device and improving the reliability can be obtained. Can be obtained.

According to a third information recording / reproducing apparatus according to the present invention, there is provided a first information recording / reproducing apparatus according to the present invention, wherein the distance control mechanism comprises: An air bearing surface formed on the optical head.

According to the present invention, in addition to the effects of the first or second information recording / reproducing apparatus according to the present invention, the near-field optical head is moved by the air bearing surface formed on the near-field optical head. Since the tracking can be performed quickly, a stable interaction always occurs between the opening and the recording medium, and a stable signal output is always obtained during recording / reproducing of information.

According to a fourth aspect of the present invention, there is provided a fourth information recording / reproducing apparatus according to the present invention, wherein the distance control mechanism is a piezoelectric actuator. is there.

According to the present invention, in addition to the effects of the first or second information recording / reproducing apparatus according to the present invention, the height of the near-field optical head and the recording medium is measured by a capacitance sensor or the like, and the measured value is obtained. Since the height of the near-field optical head and the recording medium is controlled by the piezoelectric actuator based on the height, the height of the near-field optical head and the recording medium can be controlled well, and a signal that is always stable when recording and reproducing information Recording and output signals are obtained.

According to a fifth aspect of the present invention, there is provided a fifth information recording / reproducing apparatus according to the present invention, wherein at least a part of the aperture control mechanism comprises the air It is a bearing surface.

According to the present invention, in addition to the effect of the third information recording / reproducing apparatus according to the present invention, at least a part of the cone-shaped projection serving as the aperture control mechanism is an air bearing surface. Structure can be simplified, the number of masks required for the production, the production process can be simplified, the production time can be reduced, and the production cost can be further reduced. In an information recording / reproducing apparatus according to the sixth aspect, in the first or second information recording / reproducing apparatus according to the present invention, at least a part of the aperture control mechanism is a protective section for the aperture.

According to the present invention, in addition to the effects of the first or second information recording / reproducing apparatus according to the present invention, even when minute dust on the recording medium or a strong impact is applied to the entire apparatus, the aperture control is performed. Since the portion is near the cone-shaped protrusion having the opening formed therein, the portion also has a role as a protection portion for protecting the opening, and the opening is damaged by the protection portion. The possibility that recording on a recording medium cannot be performed can be greatly reduced, the life of the information recording / reproducing apparatus can be prolonged, and the impact resistance can be greatly improved.

According to a seventh aspect of the present invention, there is provided an information recording / reproducing apparatus according to any one of the first to sixth information recording / reproducing apparatuses according to the present invention. Two or all of the cone-shaped protrusion and the distance control mechanism are formed in one step.

According to the present invention, in addition to the effects of any of the first to sixth information recording / reproducing apparatuses according to the present invention, a cone-shaped protrusion mask for forming a cone-shaped protrusion and an opening control section is provided. Can be realized by a photolithography process using one type of photomask to form a mask for the aperture control unit, and the number of photomasks and the number of exposures for creating a near-field optical head can be reduced, further reducing costs. It becomes possible.
In addition, since the mask for the cone-shaped protrusion and the mask for the opening control unit are formed by one photomask, the positional error between the two masks can be reduced. In addition, since the step of creating the conical protrusion and the step of creating the opening control section can be realized in one step, the creation step can be simplified, the creation time can be reduced, and the creation cost can be further reduced.
Furthermore, since the process of creating the air bearing surface can also be formed by a photolithography process, a near-field optical head can be created by sharing a part of the mask with the mask for the cone-shaped protrusion and the mask for the aperture control unit. The number of masks can be reduced. Although it depends on the detailed structure of the near-field optical head, the head can also be formed with one type of mask, so that the manufacturing process can be further simplified, the creation time can be further reduced, and the creation cost can be further reduced.

According to an eighth aspect of the present invention, there is provided an information recording / reproducing apparatus according to the present invention, wherein the opening is provided in the near-field optical head. Are formed.

According to the present invention, in addition to the effects of the first or second information recording / reproducing apparatus according to the present invention, a plurality of apertures can be created in one near-field optical head, and information can be recorded on a recording medium. Since the recording of information and the reproduction of recorded information can be performed in parallel by the number of apertures, high-speed recording of information on a recording medium and reproduction of information from a recording medium can be realized.

[0029]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a method for forming an opening according to the present invention will be described in detail with reference to the accompanying drawings. (Embodiment 1) FIG. 1 schematically shows an information recording / reproducing apparatus according to Embodiment 1 of the present invention. In order to make the outline of the information recording / reproducing apparatus easy to understand, the suspension arm 10
9, the flexure 110 and the near-field optical head 106, and the suspension arm 111 and the light-receiving head 108 are shown in an exploded form, but actually, they are connected and fixed as needed.

The information reproducing apparatus according to the present embodiment has a similar basic structure to a conventional magnetic disk drive, and has a near-field optical head 10 having an aperture (not shown) for generating near-field light.
6 is rotated at a high speed in a state where the recording medium 107 is close to the surface of the recording medium 107 up to several tens of nanometers, and the near-field optical head 106 always floats with the recording medium 107 in a fixed relative position. It is formed at the tip of the suspension arm 109. The suspension arm 109 is movable in the radial direction of the recording medium 107 by a voice coil motor (not shown). here,
The near-field optical head 106 is arranged so that the opening faces the recording medium 107.

In order to guide the light beam from the laser 101 to the near-field optical head 106, an optical fiber 103 fixed to a suspension arm 109, a lens 104, and a mirror 105 are used.

Here, the optical fiber 103 is used.
This may use optical waveguides or aerial light propagation. Also,
If necessary, the laser 101 can be subjected to intensity modulation or the like by the circuit system 112.

Next, a method of reproducing information recorded on the recording medium 107 and a method of recording information will be described with reference to FIG.

The near-field optical head 106 having an optical aperture attached to the tip of the suspension arm 109 is floated to a certain height by the flying head technique, and an arbitrary data mark existing on the recording medium 107 is accessed. For this purpose, an air bearing surface is created in the near-field optical head. Further, in order to make the near-field optical head 106 follow the recording medium 107 rotating at a high speed, a function of a flexure 110 for stabilizing the posture corresponding to the undulation of the recording medium 107 is provided. A light beam emitted from the laser 101 is incident on a near-field optical head 106 by a lens 102, an optical fiber 103, a lens 104, and a mirror 105 having a light guiding structure. Thereafter, the light is guided to the opening of the near-field optical head 106, and near-field light is generated near the opening. The scattered light generated as a result of the interaction between the near-field light and the recording medium 107 is received by the light receiving head 108 fixed to the suspension arm 111, converted into an electric signal, and transmitted to the circuit system 112. This is amplified as needed to obtain an information reproduction signal. To record information on the recording medium 107, the near-field optical head 106 having an opening at a desired position of the recording medium is moved while the recording medium 107 is brought close to the opening, and near-field light is transmitted from the opening to the recording medium 107. It is realized by irradiating and performing a writing operation.

In the present embodiment, the near-field optical head 106 and the light-receiving head 108 for generating near-field light are respectively attached to the suspension arms, but the near-field optical head 106 and the light-receiving head 108 are integrated into one suspension. It is also possible to carry out with a suspension arm.

Further, the illumination mode in which near-field light is generated from the opening and scattered by the recording medium is performed. In the collection mode in which near-field light is generated on the recording medium surface and light scattered by the opening is collected. The implementation of the present invention can be performed similarly.

Since the interaction utilizing near-field light is used for reproducing and recording information from the recording medium, recording and reproducing at a recording density exceeding the diffraction limit of light can be realized. The near-field light generated from the opening attenuates strongly depending on the distance from the opening. However, the near-field optical head uses the air bearing surface formed in the near-field optical head and the flexure structure in the present embodiment to reduce the near-field optical head. In order to follow the movement, a stable interaction always occurs, and a stable signal output is always obtained during recording / reproducing of information.

In this embodiment, the flying head technology used in the HDD or the like is used for controlling the heights of the near-field optical head 106 and the recording medium 107. However, besides this control method, the near-field optical head 106 and the recording medium 1
07 is measured with a capacitance sensor or the like, and the near-field optical head 10 is measured with a piezoelectric actuator based on the measured height.
6 and the method of controlling the height of the recording medium 107 can also realize the information recording / reproducing apparatus. Even with such a piezoelectric actuator, the heights of the near-field optical head 106 and the recording medium 107 can be controlled well, and a stable signal recording and output signal can always be obtained in recording and reproducing information.

Next, a method of manufacturing the near-field optical head used in the first embodiment will be described.

FIGS. 2 to 4 are views for explaining a method for producing a near-field optical head of the information recording / reproducing apparatus according to the first embodiment of the present invention. The work 2000 shown in FIG.
The transparent layer 205 formed on the substrate 204, the weight-shaped protrusion 201 and the ridge-shaped opening control part 202 formed on the transparent layer 205, and the weight-shaped protrusion 201 and the opening control part 202 and the transparent layer 205 are formed. The light shielding film 203 is formed on the substrate. In the work 2000, the transparent layer 205
It is not always necessary, and in that case, the light-shielding film 203 is formed on the conical protrusion 201, the opening control unit 202, and the substrate 204. Further, the light-shielding film 203 is
Only one may be deposited.

The height of the conical protrusion 201 is several mm or less, and the height of the opening control part 202 is several mm or less.
In the present embodiment, the height of the weight-shaped protrusion 201 is the same as the height of the opening control unit 202. Plumb 201
And the opening control section 202 is at most a few mm. Also,
Although the thickness of the light-shielding film 203 varies depending on the material of the light-shielding film 203, it is several tens nm to several hundreds nm.

The conical protrusion 201, the aperture control unit 202, and the transparent layer 205 are made of a dielectric material having a high transmittance in the visible light region such as silicon dioxide or diamond, or a dielectric material having a high transmittance in the infrared light region such as zinc selenium or silicon. A high dielectric material or a material having a high transmittance in an ultraviolet light region, such as magnesium fluoride or calcium fluoride, is used. Also,
As the material of the conical protrusion 201, any material that can transmit the conical protrusion 201 at least in a wavelength band of light passing through the opening can be used. Further, the weight-shaped protrusion 201, the opening control unit 202, and the transparent layer 205 may be made of the same material or may be made of different materials. The light shielding film 203 is made of, for example, aluminum, chromium, gold,
Metals such as platinum, silver, copper, titanium, tungsten, nickel, and cobalt, and alloys thereof are used.

FIG. 3 is a view showing a state in which the light-shielding film 203 on the conical protrusion 201 is plastically deformed in the method of forming the opening. The plate 206 and the pushing tool 20 serve as a pushing body for plastically deforming the light shielding film 203.
7 was used. On the work 2000 shown in FIG. 2, a plate 206 that covers the weight-shaped protrusion 201 and at least a part of the opening control unit 202, and that has at least the weight-shaped protrusion 201 and the opening control unit 202 side as a plane is placed. Further, the pushing tool 207 is placed on the plate 206. By applying a force F to the pushing tool 207 in the direction of the central axis of the weight-like protrusion 201, the plate 206 moves toward the weight-like protrusion 201. The contact area between the opening control unit 202 and the plate 206 is several hundred to tens of thousands times larger than the contact area between the conical protrusion 201 and the plate 206. Therefore, the applied force F is dispersed by the aperture control unit 202, and as a result, the displacement of the plate 206 is reduced. Since the amount of displacement of the plate 206 is small, the amount of plastic deformation received by the light shielding film 203 is very small. Further, the weight-shaped protrusion 201 and the opening control unit 202 receive only a very small elastic deformation.
The method of applying the force F includes a method of lifting a weight having a predetermined weight by a predetermined distance and allowing it to freely fall, and a method of attaching a spring having a predetermined spring constant to the pushing tool 7 and pressing the spring for a predetermined distance. is there. When the plate 206 is made of a material that is harder than the light-shielding film and softer than the weight-shaped protrusion 201 and the opening control unit 202, the force received by the weight-shaped protrusion 201 and the opening control unit 202 is absorbed by the plate 206. , The displacement of the plate 206 becomes smaller, and the light shielding film 2
03 can be easily reduced.

FIG. 4 is a view showing a state in which the plate 206 and the pushing tool 207 as the pushing body are removed after the force F is applied. Since the amount of plastic deformation of the light-shielding film 203 is very small, and the weight-like protrusion 201 and the opening control unit 202 are displaced only in the elastic deformation region, the weight-like protrusion 20
An opening 208 is formed at one end. The size of the opening 208 is about several nm to about the diffraction limit of the wavelength of light passing through the conical protrusion 201. In the above description, the plate 206 is inserted between the pressing tool 207 and the work 2000. However, the plate 206 is removed and the pressing tool 20 is directly inserted.
It goes without saying that the opening 208 can be similarly formed by pushing in with 7.

In order to introduce light into the opening 208,
By etching the substrate 204 from the side opposite to the surface on which the weight-shaped protrusion 201 is formed, a tapered portion 401 is formed, and at least a part of the transparent body 205 or the weight-shaped protrusion 201 is exposed, and light is transmitted to the opening 208. Form an inlet. Also,
When the substrate 4 is made of a transparent material, it goes without saying that the step of forming the light inlet can be omitted. Further, the tapered portion 401 may be formed before the light shielding film 203 is formed.

Further, by controlling the height of the weight-like protrusion 201 and the height of the opening control part 202, the weight-like protrusion 2
01, the amount of displacement of the upper light-shielding film can be controlled, and the size of the opening formed at the tip of the conical projection 201 can be controlled.

Further, the opening control section 202
, And the height is the same for both. Therefore, the opening control unit 202 also functions as a protection unit that protects the opening 208.

Further, in this embodiment, the plate 206 is pushed by the tool 207 to push the plate 206 to create the opening.
An opening can be similarly created by pressing 0 against the plate 206.

In the near-field optical head according to the present embodiment, the aperture control unit 202 is disposed,
08, the aperture control unit 202 may be removed.

Further, the aperture control unit 202 is not formed on the near-field optical head 106 but is formed on the plate 206 side, and the plate 206 is pushed by the pushing tool 207 to press the weight-like projection 201 or the work is formed on the plate. An opening can be similarly created by pressing. In that case, it goes without saying that the near-field optical head does not have an aperture control unit.

As described above, according to the opening forming method of the present invention, the amount of displacement of the plate 206, which is a push body, can be favorably controlled by the opening control unit 202, and the amount of displacement of the plate 206 can be reduced. Since it can be made very small, a small opening 208 having a uniform size can be easily formed at the tip of the weight-like projection 201. In addition, light can be emitted from the substrate side to generate near-field light from the opening 208.

Next, a method of manufacturing the work 2000 will be described with reference to FIGS. FIG. 5 shows that after forming a transparent material 503 on a substrate material 504, a mask 5
01 and a state in which a mask 502 for an opening control unit is formed. FIG. 5A shows a top view, and FIG.
FIG. 5B is a cross-sectional view at a position indicated by AA ′ in FIG. The transparent material 503 is formed on the substrate material 504 by chemical vapor deposition (CVD) or spin coating. Further, the transparent material 503 can also be formed on the substrate material 504 by a method such as solid phase bonding or adhesion. Next, a mask 501 for a pyramidal projection and a mask 502 for an opening control unit are formed over the transparent material 503 by a photolithography process using a photomask. Conical projection mask 501 and aperture control mask 502
May be formed simultaneously or separately.

The mask 501 for the cone-shaped protrusions and the mask 502 for the aperture control unit are made of a photoresist or a nitride film, depending on the material of the transparent material 503 and the etchant used in the next step. The transparent material 503 is made of a dielectric material having a high transmittance in a visible light region such as silicon dioxide or diamond, a dielectric material having a high transmittance in an infrared light region such as zinc selenium or silicon, or a material such as magnesium fluoride or calcium fluoride. A material having a high transmittance in an ultraviolet light region is used.

The diameter of the cone-shaped projection mask 501 is, for example, several mm or less. The width W1 of the opening control unit mask 502 is, for example, equal to or smaller than the diameter of the cone-shaped projection mask 501 by several tens nm to several μm. In addition, the length of the opening control unit mask 502 is several tens μm or more.

FIG. 6 shows a state in which the weight-like projection 201 and the opening control section 202 are formed. FIG. 6A is a top view, and FIG. 6B is a cross-sectional view taken along a line AA ′ in FIG. 6A. After forming the cone-shaped projection mask 501 and the opening control section mask 502, the cone-shaped projection 2 is isotropically etched by wet etching.
01 and the aperture control unit 202 are formed. Transparent material 50
The transparent layer 205 shown in FIG. 2 may or may not be formed by adjusting the relationship between the thickness of No. 3 and the heights of the weight-shaped protrusion 201 and the opening control unit 202. The tip radius of the conical protrusion 201 is several nn to several hundred nm. Thereafter, a work 2000 shown in FIG. 2 can be formed by depositing a light shielding film by a method such as sputtering or vacuum evaporation. Further, the light-shielding film 203 is
In the case where the light-shielding film 203 is deposited only, in the step of depositing the light-shielding film 203, a metal mask having a shape such that the light-shielding film is deposited on the conical projection 201 is put thereon, and sputtering or vacuum deposition is performed. Further, after the light shielding film 203 is deposited on the entire surface of the work 2000 on which the cone-shaped protrusions are formed, a photolithography process in which the light-shielding film 203 is left only on the cone-shaped protrusions 201 may be used. Needless to say, the light shielding film 203 can be formed only on the portion 201.

Further, the near-field optical head shown in FIG.
Since the flying head technology used for D and the like is used, an air bearing surface is required to control the height of the near-field optical head 106 and the recording medium 107 to a constant value. This air bearing surface can be formed by photolithography on the side where the weight-shaped protrusion 201 is formed before the light-shielding film 3 is formed. Further, the opening control section can be used as the air bearing surface. As explained above,
According to the first embodiment of the present invention, since the opening control section 202 is provided in the vicinity of the weight-shaped projection 201, the displacement amount of the plate 206, which is a push body, can be reduced.
It is easy to form a small opening 208 having a uniform size at the tip of the weight-shaped protrusion 201 without using an actuator having a high resolution. In our experiment, we just hit the pushing tool 7 with a hammer, etc.
An opening 208 of m or less could be formed. In addition, since the height of the weight-shaped protrusion 201 and the height of the opening control unit 202 are always controlled to be the same, the production yield of the opening 208 is improved. Further, the work 20 described in the first embodiment of the present invention.
00 can be formed by a photolithography process, so that a plurality of samples can be formed on a sample having a large area such as a wafer. Thus, the opening 208 having a uniform opening size can be formed. Further, since it is very easy to change the magnitude of the force F, it is possible to individually form openings 208 having different opening sizes for a plurality of works 2000. Further, since the opening 208 is formed simply by simply applying the force F, the time required for forming the opening is very short, from several seconds to several tens of seconds. Therefore, a large number of near-field optical heads can be produced at a low price, and the information recording / reproducing apparatus can be made at a very low price. Further, according to the first embodiment of the present invention, the process of forming the opening is not limited to the processing atmosphere. Therefore, processing can be performed in the atmosphere, and the processing state can be immediately observed with an optical microscope or the like. Further, by processing in a scanning electron microscope, it is possible to observe the processing state at a higher resolution than in an optical microscope. Further, by processing in a liquid, the liquid functions as a damper, so that processing conditions with further improved controllability can be obtained. Therefore, the accuracy of the aperture size of the near-field optical head is improved, and variations between devices are reduced, and stable recording and reproduction can be performed.

Further, a plurality of openings 208 having a uniform opening size can be formed at once by applying a force F to a sample on which a plurality of works 2000 are formed. In the case of processing all at once, the processing time per opening is very short, several hundred milliseconds or less, depending on the number of works 2000 per wafer. It is also easy to create a plurality of apertures in one near-field optical head. In this case, recording of information on a recording medium and reproduction of recorded information can be performed in parallel with the number of apertures. High-speed recording of information on a medium and reproduction of information from a recording medium can be realized.

Further, in the case where the mask for the cone-shaped protrusion and the mask for the opening control unit for forming the cone-shaped protrusion and the opening control unit are formed by a photolithography process using one type of photomask. In addition, the number of photomasks and the number of exposures for fabricating the near-field optical element can be reduced, and the cost can be further reduced. In addition, since the mask for the cone-shaped protrusion and the mask for the opening control unit are formed by one photomask, the positional error between the two masks can be reduced. In addition, since the step of creating the conical protrusion and the step of creating the opening control section can be realized in one step, the creation step can be simplified, the creation time can be reduced, and the creation cost can be further reduced. Furthermore, since the process of creating the air bearing surface can also be formed by a photolithography process, a near-field optical head can be created by sharing a part of the mask with the mask for the cone-shaped protrusion and the mask for the aperture control unit. The number of masks can be reduced. Although it depends on the detailed structure of the near-field optical head, it can be made with one type of mask, which can further simplify the creation process, reduce the creation time, and further reduce the creation cost. When the bearing surface is a pyramidal projection, the structure of the near-field optical head is simplified,
A reduction in the number of masks required for fabrication, simplification of the fabrication process, and a reduction in fabrication time and further reduction in fabrication cost can be realized. Because it is plastically deformed,
The thickness of the light-shielding film in the vicinity of the opening is thick and strong. Therefore, the light blocking ratio in the vicinity of the opening is improved, and when recording information on the recording medium, the edges of the recording marks are clearly recorded, so that information can be reproduced from the recording medium on which the information has been recorded.
SN can be improved. In addition, since the strength of the opening is increased, the service life can be improved by increasing the impact resistance and wear resistance.

Further, when a minute dust on the recording medium or a strong impact is applied to the entire apparatus, the opening control section is located near the cone-shaped projection having the opening, so that the protection section for protecting the opening is provided. It also has the role of With this protection,
The possibility that the opening is damaged and the information recorded on the recording medium cannot be reproduced or cannot be recorded on the recording medium can be greatly reduced, the life of the information recording / reproducing apparatus can be extended, and the impact resistance can be greatly improved. Can be improved. (Embodiment 2) FIG. 7 is a diagram showing an information recording / reproducing apparatus according to Embodiment 2 of the present invention. In this embodiment,
This is an embodiment in which an opening forming mechanism is added to the first embodiment of FIG. Therefore, portions other than the opening forming mechanism are the same as those in the first embodiment, and the description of the same portions as those in the first embodiment will be partially omitted or simplified.

FIG. 7 shows the information recording / reproducing apparatus described in the first embodiment of FIG.
FIG. 13 is a view of the top view of the apparatus with the addition of the opening creation unit 702 and the top view.

In the second embodiment, when the opening of the near-field optical head 106 is damaged due to an impact applied to the information recording / reproducing device, abrasion, aging, etc. Film forming portion 701 provided in
An opening can be formed again without removing the near-field optical head from the apparatus by the opening forming mechanism including the opening forming unit 702 and the opening forming unit 702.

When the opening of the near-field optical head 106 is damaged, the light-shielding film forming the opening may come off,
There is a case where a deposit is attached to the upper part of the opening and blocks the opening.

Therefore, a light-shielding film is formed again at the tip of the conical protrusion in the light-shielding film forming portion 701, and then the opening forming portion 7
At 02, an opening is created at the tip of the conical projection.

Needless to say, an opening can be created in the opening forming section 702 by incorporating the information recording / reproducing apparatus of the present embodiment into the information recording / reproducing apparatus without forming an opening at the tip of the conical projection of the near-field optical head.

The method of recording information on the recording medium 107 and the method of reproducing the information in the second embodiment are exactly the same as those in the first embodiment, and a description thereof will be omitted.

Next, a method for forming an opening using the opening forming mechanism will be described.

FIG. 8 shows the vicinity of the light-shielding film forming portion of the opening forming mechanism. The light-shielding film forming portion 701 includes a light-shielding film material container 802.
And the light shielding film material 801 set in the light shielding film material container 802. The light shielding film material container 802 includes a heater for melting the set light shielding film material 801.

The near-field optical head 106 is connected to the light-shielding film forming section 70.
The light shielding film material 801 put in the light shielding film material container 802 is heated by the heater of the light shielding film material container 802 to melt the light shielding film material 801. The tip of the conical projection 201 of the near-field optical head 106 is inserted into the melted light shielding film material 801. Thereafter, the heating of the heater is stopped so that the tip of the weight-like projection 201 is covered with the light shielding film material.

The light-shielding film material 801 is made of, for example, a metal such as aluminum, chromium, gold, platinum, silver, copper, titanium, tungsten, nickel or cobalt, or an alloy thereof. This light shielding film material 801 is used for the near-field optical head 106.
It is desired that the material be the same as that of the light-shielding film 203.
Yes, they need not be the same.

Next, the cone-shaped protrusion 20 is formed by the light-shielding film forming portion.
1 moves the near-field optical head 106 covered with the light-shielding film to the upper part of the opening forming part 702.

FIG. 9 shows the vicinity of the opening forming portion of the opening forming mechanism. The opening forming part 702 includes the plate 901 and the pushing tool 90.
Consists of two. The method of forming an opening using the plate 901 and the pushing tool 902 is exactly the same as the method described in the first embodiment, and a description thereof will be omitted.

The conical projection 201 of the near-field optical head 106
In the case where an adhered substance is attached to the tip of the opening, the step in the light shielding film forming section 701 can be omitted, and the opening can be formed again only by the step in the opening forming section 702.

As described above, according to the second embodiment of the present invention, the aperture of the normal near-field optical head 106 is damaged for some reason, and the reproduction of data recorded on the recording medium and the recording of data are not performed. If you can no longer do that,
The aperture of the near-field optical head can be created again to record and reproduce data.

When a structure in which a recording medium employed in an HDD or the like is fixed inside the information recording / reproducing apparatus is used in the present information recording / reproducing apparatus, the opening of the near-field optical head is once damaged. Thus, even recorded data cannot be reproduced, and important data is lost. According to the present embodiment, even in such a situation, not only reproduction of recorded information but also reproduction to a recording medium can be performed. Information can be recorded, and the reliability of the information recording / reproducing apparatus is dramatically improved. Furthermore, even when the information recording / reproducing apparatus uses a structure in which a recording medium such as MO or DVD-RAM is replaceable, the life of the apparatus can be greatly extended, and the life of the apparatus can be extended. An effect such as improvement in reliability can be obtained.

In the second embodiment, since the information recording / reproducing apparatus described in the first embodiment is provided with an opening forming mechanism, all the effects described in the first embodiment are combined. The reliability of the entire apparatus can be greatly improved with a slight increase in the cost of the forming mechanism.

Further, the near-field optical head can be incorporated in the information recording / reproducing apparatus without forming an opening when manufacturing the near-field optical head, and then the opening can be formed in the opening forming section.

[0077]

As described above, according to the first information recording / reproducing apparatus of the present invention, in the near-field optical head used for the information recording / reproducing apparatus, the aperture control section is provided in the vicinity of the conical projection. Since the displacement of the plate, which is the indented body, can be reduced, it is easy to form a uniform and minute opening at the tip of the weight-shaped projection without using an actuator with high resolution. A high-density information recording / reproducing device can be realized.

Further, since the height of the cone-shaped protrusion and the height of the aperture control section are always controlled to be the same, the production yield of the aperture of the near-field optical head is improved, and the quality of the information recording / reproducing apparatus is stabilized.

Further, since the near-field optical head can be formed by a photolithography process, a plurality of near-field optical heads can be formed on a sample having a large area such as a wafer. An opening having a uniform opening size can be formed for each of the created works. Further, since it is very easy to change the magnitude of the force F, it is possible to individually form openings having different opening sizes for a plurality of workpieces. Also, since the opening is formed by simply applying the force F,
The time required to create the opening is very short, from several seconds to several tens of seconds.
Therefore, a large number of near-field optical heads can be manufactured at a low price, and the information recording / reproducing apparatus can be made at a significantly lower price. Further, since the process of forming the opening does not depend on the processing atmosphere, the processing can be performed in the air, and the processing state can be immediately observed with an optical microscope or the like. Further, by processing in a scanning electron microscope, it is possible to observe the processing state at a higher resolution than in an optical microscope. Also, by working in liquid, the liquid acts as a damper,
Processing conditions with improved controllability can be obtained. Therefore, the accuracy of the aperture size of the near-field optical head is improved, and variations between devices are reduced, and stable recording and reproduction can be performed. Further, by applying a force F to a sample in which a plurality of workpieces are created at once, it is possible to create a plurality of apertures having the same aperture size at one time. In the case of processing all at once, the processing time per opening is very short, several hundred milliseconds or less, depending on the number of workpieces per wafer.
Therefore, mass production of the near-field optical head used for the information recording / reproducing apparatus is possible, and the cost can be reduced.

Further, around the opening of the near-field optical head,
Since the light-shielding film near the tip of the cone-shaped protrusion is plastically deformed by being placed on the plate, the thickness of the light-shielding film near the opening is thick and strong. Therefore, the light blocking ratio in the vicinity of the opening is improved, and when recording information on the recording medium, the edges of the recording marks are clearly recorded, thereby improving the SN of information reproduction from the recording medium on which the information is recorded. it can. Also,
Since the strength of the opening is increased, the service life can be improved by increasing the impact resistance and the abrasion resistance. As described above, according to the second information recording / reproducing apparatus of the present invention, in addition to the effect of the first information recording / reproducing apparatus of the present invention, the opening of the normal near-field optical head is damaged for some reason. Even when the data recorded on the recording medium cannot be reproduced or the data cannot be recorded, the opening of the near-field optical head can be created again to record and reproduce the data. Even in situations where the aperture of the near-field optical head is damaged once, or even the data recorded so far cannot be reproduced, and important data is lost, not only the recorded information can be reproduced but also recorded. It is also possible to record information on a medium, and the reliability of the information recording / reproducing apparatus is dramatically improved.
Furthermore, even when the information recording / reproducing apparatus uses a structure in which a recording medium such as MO or DVD-RAM is replaceable, the life of the apparatus can be greatly extended, and the life of the apparatus can be extended.
An effect such as improvement in reliability can be obtained. As described above, according to the third information recording / reproducing apparatus of the present invention, in addition to the effects of the first or second information recording / reproducing apparatus of the present invention, the air bearing surface formed on the near-field optical head As a result, the near-field optical head can quickly follow the movement of the recording medium, so that a stable interaction always occurs between the aperture and the recording medium, and a stable signal output is always obtained during recording / reproduction of information. As described above, according to the fourth information recording / reproducing apparatus according to the present invention, the first information recording / reproducing apparatus according to the present invention
Alternatively, in addition to the effect of the second information recording / reproducing device, the height of the near-field optical head and the recording medium is measured by a capacitance sensor or the like,
The height of the near-field optical head and the recording medium is controlled by the piezoelectric actuator based on the measured height, so that the height of the near-field optical head and the recording medium can be controlled well, and in recording and reproducing information. A stable signal recording and output signal can always be obtained. As described above, according to the fifth information recording / reproducing apparatus of the present invention, in addition to the effect of the third information recording / reproducing apparatus of the present invention, at least a part of the cone-shaped projection serving as the opening control mechanism is provided. Since the air bearing surface is used, the structure of the near-field optical head is simplified, and the number of masks required for the production, the production process can be simplified, the production time can be reduced, and the production cost can be further reduced. As described above, according to the sixth information recording / reproducing apparatus according to the present invention, in addition to the effects of the first or second information recording / reproducing apparatus according to the present invention, minute dust on the recording medium or strong impact on the entire apparatus is obtained. Even when the opening is added, since the opening control unit is located near the weight-shaped protrusion having the opening, the opening control unit also has a role as a protection unit for protecting the opening. The opening is damaged by the protection unit, and the recording medium is damaged. Greatly reduce the possibility can not be recorded on the reproducing or recording medium is recorded information, can prolong the life of the information recording and reproducing apparatus, and, impact resistance can also be greatly improved.

As described above, according to the seventh information recording / reproducing apparatus according to the present invention, in addition to the effects of any of the first to sixth information recording / reproducing apparatuses according to the present invention, in addition to the conical projections, A photolithography process can be realized by using one type of photomask to form a cone-shaped projection mask for forming an aperture control unit and a mask for an aperture control unit, and the number of photomasks for producing a near-field optical head And the number of times of exposure can be reduced, and the cost can be further reduced. Also,
Since the mask for the cone-shaped protrusion and the mask for the opening control unit are formed by one photomask, the positional error between the two masks can be reduced. In addition, since the step of creating the conical protrusion and the step of creating the opening control section can be realized in one step, the creation step can be simplified, the creation time can be reduced, and the creation cost can be further reduced. Furthermore, since the process of creating the air bearing surface can also be formed by a photolithography process, a near-field optical head can be created by sharing a part of the mask with the mask for the cone-shaped protrusion and the mask for the aperture control unit. The number of masks can be reduced. Although it depends on the detailed structure of the near-field optical head, the head can also be formed with one type of mask, so that the manufacturing process can be further simplified, the creation time can be further reduced, and the creation cost can be further reduced.

As described above, according to the eighth information recording / reproducing apparatus according to the present invention, in addition to the effects of the first or second information recording / reproducing apparatus according to the present invention, a single near-field optical head is provided with a plurality of information recording / reproducing apparatuses. Apertures can be created, and information can be recorded on the recording medium and the recorded information can be reproduced in parallel by the number of apertures.
Reproduction of information from a recording medium can be realized.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating a configuration of an information recording / reproducing apparatus according to Embodiment 1 of the present invention.

FIG. 2 is a diagram for explaining a method of producing the near-field optical head according to the first embodiment of the present invention.

FIG. 3 is a diagram for explaining a method for producing the near-field optical head according to the first embodiment of the present invention.

FIG. 4 is a diagram illustrating a method for producing the near-field optical head according to the first embodiment of the present invention.

FIG. 5 is a diagram illustrating a method of manufacturing a work 2000.

FIG. 6 is a diagram illustrating a method of manufacturing a work 2000.

FIG. 7 is a diagram illustrating a configuration of an information recording / reproducing apparatus according to Embodiment 2 of the present invention.

FIG. 8 is a diagram illustrating a light-shielding film forming portion according to a second embodiment of the present invention.

FIG. 9 is a diagram illustrating an opening creating unit according to Embodiment 2 of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 101 Laser 102, 104 Lens 103 Optical fiber 105 Mirror 106 Near-field optical head 107 Recording medium 108 Light receiving head 109, 111 Suspension arm 110 Flexure 112 Circuit system 201 Conical projection part 202 Opening control part 203 Light shielding film 204 Substrate 205 Transparent layer 206 901 plate 207, 902 push tool 208 opening 401 taper portion 501 cone-shaped projection portion mask 502 opening control portion mask 503 transparent material 504 substrate material 701 light shielding film forming portion 702 opening forming portion 801 light shielding film material 802 light shielding film material input 2000 Work F force

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Hidetaka Maeda 1-8-8 Nakase, Mihama-ku, Chiba-shi, Chiba Inside SII RRD Center Co., Ltd. (72) Inventor Kenji Kato 1 Nakase, Mihama-ku, Chiba-shi, Chiba 8-8, SII IRD Center Co., Ltd. (72) Inventor Yasuyuki Mitsuoka 1-8-1, Nakase, Mihama-ku, Chiba, Chiba Prefecture SII IRD Center Co., Ltd. (72) Susumu Ichihara Chiba, Japan 1-8-8 Nakase, Mihama-ku, Chiba-shi, Ltd. Inside SII RLD Center Co., Ltd. (72) Inventor Takashi Shinwa 1-8-8 Nakase, Mihama-ku, Chiba-shi, Chiba Co., Ltd. Inventor Yoko Shinohara 1-8-8 Nakase, Mihama-ku, Chiba-shi, Chiba F-term (reference) in the SII IRD center (5D118 AA06 AA13 BA01 CA11 EA08 EA11 EA16 5D119 AA22 AA38 BA01 CA06 JA70 MA06 NA05

Claims (8)

[Claims] A recording medium; a light source; a near-field optical head having an opening on the recording medium side; a distance control mechanism for controlling a distance between the near-field optical head and the recording medium; An information recording / reproducing apparatus for recording or reproducing information using near-field light, comprising: a light guide structure for guiding a light beam to the near-field optical head; and a light receiving unit. At least one weight-shaped protrusion that transmits the same wavelength, a light-shielding film that covers at least the weight-shaped protrusion, and a height substantially equal to the height of the weight-shaped protrusion and the weight-shaped protrusion using a pressing body having a substantially flat surface. An information recording / reproducing apparatus, comprising: an opening formed at the tip of the weight-shaped projection by simultaneously applying a force to the opening control section having a height. A recording medium; a light source; a near-field optical head having an opening on the recording medium side; a distance control mechanism for controlling a distance between the near-field optical head and the recording medium; An information recording / reproducing apparatus configured to record or reproduce information using near-field light, comprising: a light guide structure for guiding a light beam to the near-field optical head; a light receiving unit; and an aperture forming mechanism. An optical head, at least one weight-shaped projection that transmits a desired wavelength, a light-shielding film that covers at least the weight-shaped projection, and the weight-shaped projection and the weight-shaped projection using a substantially flat indentation body. And an opening formed at the tip of the weight-shaped projection by simultaneously applying a force to the opening control section having substantially the same height as the section, wherein the opening forming mechanism comprises a light shielding film forming section and an opening forming section. Composed Information recording and reproducing apparatus characterized by there. 3. The information recording / reproducing apparatus according to claim 1, wherein the distance control mechanism is an air bearing surface formed on the near-field optical head. 4. The apparatus according to claim 1, wherein the distance control mechanism is a piezoelectric actuator.
An information recording / reproducing apparatus according to claim 1. 5. At least a part of the distance control mechanism includes:
The information recording / reproducing apparatus according to claim 3, wherein the information recording / reproducing apparatus is the air bearing surface. 6. At least a part of the distance control mechanism,
3. The information recording / reproducing apparatus according to claim 1, wherein the information recording / reproducing apparatus is a protection section for the opening. 7. The apparatus according to claim 1, wherein two or all of the opening control section, the weight-shaped projection section, and the distance control mechanism are formed in one step. Information recording and reproducing device. 8. The information recording / reproducing apparatus according to claim 1, wherein a plurality of the openings are formed in the near-field optical head.