DETAILED DESCRIPTION OF THE INVENTION
BACKGROUND OF THE INVENTION 1. Field of the Invention
With regard to a disk manufacturing method and a three-dimensional fine processing method using the same,
In particular, it has a continuous density distribution as a mask pattern
Fabrication method of gray scale mask and three-dimensional fine
It relates to a fine processing method.
2. Description of the Related Art In recent years, electron beam lithography systems and laser
Contact drawing device and HEBS glass (High-Ene
Has been proposed for grayscale masks.
Chlorens and micro prisms have been manufactured (Ap
Plied Optics, Vol. 36, no. 2
0, 1997 pp. 4675-4680; Appli
ed Optics, Vol. 37, no. 32,19
98, pp. 7568-7576). These devices and
Lass is expensive and, in addition, the usual electron beam writing equipment
GDS2 format designed by CAD for integrated circuits
Grayscale for lines
It had to be expressed in combination. Conventionally,
Transfer the pattern of the ray scale mask to the resist
Transferred to glass using reactive ion etching technology
Therefore, the process was complicated and the cost was high. Also,
Lines such as the above are displayed on photosensitive glass in combination.
Exposure directly through the revealed grayscale mask
It has also been proposed to perform three-dimensional processing by (0-7)
803-4412-X / 98, 1998 IEEE, p.
p. 207-210), such a gray scale mass
It was not easy to make a lock.
The present invention relates to the prior art.
It was made in view of such problems as
Is a commercial parser without special drawing equipment or drawing software.
Using CAD software and printer for Sonal Computer
To produce a grayscale mask for 3D microfabrication
Method, its grayscale mask and photosensitive glass
Simple and inexpensive 3D microfabrication method in combination
It is to provide.
[MEANS FOR SOLVING THE PROBLEMS]
Akira's grayscale mask fabrication method is for 3D microfabrication
Gray scale mask
Black or black using a printer or laser printer.
A transparent pattern is expressed as a shade pattern expressed by the density of transparent pixels.
Print the original on a white sheet or white sheet
Original image expressed in coarse or dense black or opaque pixels
Using shadow optics, the image of each pixel of the original image is blurred and adjacent
For photographic materials at a magnification that cannot be resolved by being averaged with the pixel image
It is a method characterized by being produced by copying.
In this case, the reduction projection optical system uses
The image of each pixel is geometrically reduced to 0.5 μm or less
It is desirable to project on photographic materials at magnification.
The present invention has been manufactured in this manner.
It includes a grayscale mask.
The three-dimensional microfabrication method of the present invention
The gray scale mask manufactured by the manufacturing method
Contact the photosensitive glass with different etching amount
The photosensitive glass is sensed through the gray scale mask.
Irradiating the photosensitive glass,
The above sensitivity can be obtained by etching with a constant etching solution.
It is characterized by subjecting the surface of optical glass to three-dimensional fine processing.
Another three-dimensional microfabrication method of the present invention
Is a grayscale mask manufactured by the above method
With a photoresist whose etching amount varies depending on the exposure amount
Contact the surface of the substrate on which the layer of
The photoresist has sensitivity through a metal mask
Irradiating the photoresist layer with light,
Etch the photoresist layer with the specified etching solution
Through the remaining photoresist pattern.
Dry etching by reactive ion etching
By performing three-dimensional fine processing on the surface of the substrate,
And a method characterized by the following.
In the present invention, the ink jet printing
Black or opaque using a printer or laser printer.
Transparent sheet as a shade pattern expressed by the density of bright pixels
Print the original on a white sheet or white sheet
Reduced projection of the original image expressed in coarse or dense black or opaque pixels
Using an optical system, the image of each pixel of the original image is
The photographic material is copied at a magnification that cannot be resolved because it is averaged with the elementary image.
By taking a picture, a gray scale machine for three-dimensional micromachining
Since the disk is manufactured, it is simpler and cheaper than the conventional method.
Grayscale masks can be designed and manufactured. This gray
By combining a scale mask and photosensitive glass
3D glass structure with a depth of several mm and an accuracy of about 10 μm
The structure can be manufactured by one exposure and etching.
Wear. Also, the gray scale mask of the present invention
Reactive ion etching technology using photoresist
It can be applied to three-dimensional microfabrication method of silicon substrate etc.
BEST MODE FOR CARRYING OUT THE INVENTION
Principle of disk fabrication method and 3D microfabrication method using it
The embodiment will be described.
Conventional gray scale mask for fine processing
Was designed with CAD for integrated circuits, as described above.
Because GDS2 format file is used, Grace
Kale had to be represented by a combination of lines.
In contrast, in the present invention, commercially available personal computers are used.
Data gradation functions of various CAD software
Gray scale with continuous density distribution
This is for producing a mask.
FIG. 1 is a diagram showing a gray scale mask according to the present invention.
FIG. 3 is a schematic diagram for explaining the basic principle of the manufacturing method.
Sonal Computer Inkjet Printer (Bab
LeJet (registered trademark) printer)
Various CAD software output from the printer
As shown in FIGS. 1 (a1) to (c1), the density expression
The density is expressed using the density of fine discrete black pixels P.
You. That is, in the case of FIG.
(B) is about 50% of the half,
(C1) is the case of about 25% of the half.
The density of such black or opaque pixels P
1 (a2) to (c) by locally averaging
As shown in 2), the concentration in the local plane is continuous.
You. FIGS. 1 (a2), (b2), and (c2) show (a)
1), (b1) and (c1).
For this purpose, in the present invention, the gray to be produced
With an enlarged scale mask, the inkjet
Use a linter or a laser printer to
Transparent) Transparent sheet as a pattern expressed by the density of pixels
Or printed on a white sheet, and the output black
(Opaque) Gray scale mass represented by density of pixels
Mask pattern when printing using the imaging optics.
High resolution photographic film, etc. projected at a reduced magnification to cancel
Bake on top.
FIG. 2 shows an arrangement for this, in which reduced projection is possible.
A high-resolution photographic film 11 and a high-performance projection lens system 1
Possible frame 3 and the above black (opaque) pixel density
Grayscale mask pattern (original image) 10
FIG. 2 shows a copying machine having a lighting device 2 for lighting.
In such an arrangement, the illumination device 2 causes the gray scale mask
The turn 10 is illuminated from the back, and the gantry 3 is
The high resolution photographic film 11 placed on the
Projection of the mask pattern 10 for example to 1/20
Image on gray scale mask pattern 10
Since the element P has a diameter of about 10 μm, the projection lens system 1
When the pixel P is reduced to 1/20 as described above, the pixel P becomes approximately
0.5 μm, but actually, the size of the projection lens system 1 is reduced.
Pixel P is blurred due to aberration and diffraction based on the limit.
Averaged on photographic film 11, high resolution
The mask obtained by developing the photographic film 11 has a density
Is a grayscale mask that is averaged and continuously distributed.
Here, the reduction magnification of the projection lens system 1 is
Means that the diameter of the pixel P is geometrically optically
It is desirable that the magnification is 0.5 μm or less in the long order.
You may make it shrink smaller than this.
As described above, in the present invention, the ink jet
Printer or laser printer, etc.
And expanded the grayscale mask to be made
The pattern expressed by the density of black (opaque) pixels in the shape
And print it on a transparent sheet or white sheet.
Grace expressed in density of black (opaque) pixels
Kale mask pattern (original image) 10 is reduced and projected optical system 1
, Each pixel is blurred and adjacent pixel on the photographic material
Copying in an averaged and unresolvable state
This is for producing a ray scale mask.
Now, in the present invention,
Photosensitive glass using the prepared gray scale mask
By performing contact exposure, gray scale mass
The concentration distribution of the etchant from the surface of the photosensitive glass
3D micro-processing of photosensitive glass
First, the characteristics of the photosensitive glass will be described.
You. Sumitomo Optical Glass Co., Ltd.
SG-1 was used. This photosensitive glass is made of SiOTwo-L
iO Two-AlTwoOThree A small amount of A
metal ions such as u, Ag, and Cu, and GeO as a sensitizerTwo
Etc. in small amounts. UV light on this photosensitive glass
Is exposed and then subjected to a heat treatment so that the exposed portion has L
iTwoO-2SiOTwo(Lithium metasilicate) precipitates
Etching by hydrofluoric acid (HF) aqueous solution
Rate is about 50 times higher than the unexposed glass.
The photosensitive glass of the present invention has
Exposure using a gray scale mask
Then, there is a density distribution on the gray scale mask.
In addition, because the photosensitive glass has transparency,
Exposure averaging occurs even when the glass is exposed,
The density of the pixel image remaining in the kale mask is averaged,
The distribution of the amount of UV exposure is transferred to the photosensitive glass.
And Therefore, the grayscale mask according to the present invention is
By combining the characteristics of the
To perform chemical cutting (etching) of any three-dimensional shape
be able to.
FIG. 3 shows a gray scale mask pattern.
(Original) Gray scale floor of CAD software when drawing 10
(Gray value) and cutting in the above photosensitive glass
The result of experimentally determining the relationship between the amount (etching depth) is shown.
You. For exposure, use a semiconductor aligner MA10 from Mikasa Corporation.
UV irradiation for 90 minutes. After that, heat treatment
After 60 minutes at 13 ° C and 90 minutes at 548 ° C,
Lithium silicate is thinly clouded by precipitation,
Unexposed parts remain transparent. Grayscale mask
When the exposure amount is changed by using
Match the density of the scale (gray value)
Lithium oxide deposition concentration controlled by gray scale
Was confirmed. The opacity increases as the exposure time increases
However, if the value exceeds the optimum value, the exposed area turns yellow and
Exposure should be less than the optimal value, because the exposed area also becomes cloudy.
Is necessary. The glass in this state is
Put into a 5 wt% HF aqueous solution at 30 ° C, and adjust the etching time.
40 minutes, 80 minutes, 120 minutes and change the cutting amount (Etchin
FIG. 3 shows that the gray scale gradation is 10%.
At ~ 30%, a practical amount of cutting cannot be obtained and surface roughness
In this range, practical cutting amount adjustment is not possible.
I couldn't. Gray scale tone 30% -80% smell
The cutting amount approximately proportional to the gray scale
The removal amount is controlled by the function of gray scale gradation and etching time.
It was possible. 90 minutes exposure, 80% gradation, etchin
After 120 minutes of etching, an etching depth of 1 mm was obtained.
When the gray scale gradation is 80% or more, the cutting amount becomes saturated.
Because of the tendency to sum, gray
Depth ratio is determined using 30% to 80% gray scale
Absolute depth is adjusted by etching time and exposure time.
FIGS. 4 and 5 show a gray scale according to the present invention.
Using a light mask 20 on the photosensitive glass plate 21.
Contact exposure through the scale mask 20
3D fine processing on the surface of the photosensitive glass plate 21
Here is an example. In the case of FIG. 4, the gray scale mask 20 and
And the gradient density area 20 where the density is low on the left and high on the right1,
20TwoUsing a gray scale mask 20 having
(A) as shown in FIG.
The cover glass 22 is placed thereon, and the cover glass 22
Irradiate ultraviolet rays 23 from the side. Then, as shown in FIG.
As shown, the cover glass 22 and the gray scale mask 2
After removing 0, a predetermined heat treatment is performed. Next, FIG.
As shown in the figure, a predetermined concentration of hydrofluoric acid (HF) aqueous solution
Grayscale mask by time etching
Slope region 2 in the depth direction according to the transmittance gradient of 20
11’, 21Two′ With a three-dimensional surface
A lath plate 21 'is obtained. If necessary, level the surface.
By applying a coating etc. for lubrication, the microphone
Lorens, microprism, microcha for biotechnology
The most suitable glass products for channels and the like can be obtained. Or this
The surface of the photosensitive glass plate 21 'having a three-dimensional surface
By applying key and electrodeposition and molding,
A plastic mold can also be made.
In the case of FIG. 5, the gray scale mask 20 is used.
Area 20 with medium densityThree, Where the concentration is relatively high
Area 20Four, Region 20 with relatively low concentrationFiveGrace with
Using the kale mask 20, as shown in FIG.
The cover glass 2 is placed on the light-sensitive glass plate 21 and the cover glass 2 is placed thereon.
2 is placed, and ultraviolet rays 23 are irradiated from the cover glass 22 side.
I do. Then, as shown in FIG.
22 and the gray scale mask 20 are removed, and
Work. Next, as shown in FIG.
Etching with a hydrofluoric acid (HF) aqueous solution for a predetermined time
, The transmittance difference of the transmittance of the gray scale mask 20
Region 21 of different depth according toThree’, 21Four, 21Five’
A photosensitive glass plate 21 'having a three-dimensional surface having
Can be Similarly, if necessary, the surface may be smoothed.
, Microprisms, microchannels for biotechnology
An optimal glass product is obtained. Or this tertiary
Plating on the surface of the photosensitive glass plate 21 'having the original surface and
By applying electrodeposition and molding, these plastics
A lock mold can also be made.
The above is a description of the gray scale mass according to the present invention.
Example of three-dimensional fine processing on photosensitive glass using
However, gray materials according to the present invention were applied to materials other than photosensitive glass.
When transferring a scale mask, as in the prior art,
Transfer grayscale mask pattern to photoresist
And then remove it using reactive ion etching technology.
Transfer to materials such as silicon.
You. An example is shown in FIG. In this case, first, FIG.
As shown, a photoresist layer is formed on a silicon substrate 24.
25 is applied by spin coating, etc.
On the gray scale mask 20. In this example
Is the gray scale mask 20 and the density is
High right and low gradient density area 206Or a repeating pattern of
A gray scale mask 20 is used. Soshi
Then, ultraviolet rays 23 are irradiated from above. Then, the same figure
Remove the gray scale mask 20 as shown in FIG.
Then, the photoresist layer 25 is etched. Photore
The etching amount of the dist layer 25 increases in proportion to the exposure amount
Resist pattern after etching
25 'is a gradient of the density of the gray scale mask 20.
Depth inclined area 25 according to6’Repeating pattern
It consists of. Then, the resist pattern 2
Reactive ion etching of silicon substrate 24 through 5 '
As shown in FIG.
Thus, according to the gradient of the density of the gray scale mask 20,
Depth inclined area 246Consists of a repeating pattern of
A silicon substrate 24 having a three-dimensional surface is obtained.
As described above, the fabrication of the gray scale mask of the present invention
Method and three-dimensional microfabrication method using it
However, the present invention is not limited to these Examples and various modifications may be made.
It is possible. Also, a gray scale mask according to the present invention
And a three-dimensional microfabrication method using the micro-optical
Not only products and micro products in biotechnology, but also various
Of micro products in the field of
As is apparent from the above description, the present invention
Gray scale mask fabrication method and three-dimensional fine
According to the fine processing method, an inkjet printer or
Is the roughness of black or opaque pixels using a laser printer, etc.
A transparent sheet or as a dense and light pattern
Print the original image on a white sheet and print the black or
Uses a projection optical system to reduce the original image expressed by the density of transparent pixels.
The image of each pixel of the original image is blurred and
Copying to a photographic material at a scaled ratio that cannot be resolved
Creates grayscale masks for 3D microfabrication
Is easier and cheaper than conventional methods.
Masks can be designed and manufactured. This grayscale machine
By combining the disc and the photosensitive glass, the depth
mm, 3D glass structure with accuracy of about 10μm once
Can be manufactured by exposure and etching. Ma
In addition, the gray scale mask of the present invention is
And a reactive ion etching technique.
Can be applied to 3D microfabrication methods such as recon boards
BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic diagram for explaining a basic principle of a method for manufacturing a gray scale mask of the present invention. FIG. 2 is a diagram showing an example of an arrangement in which a gray scale mask according to the present invention is copied from an original image using a reduction projection optical system. FIG. 3 is a diagram showing a result of experimentally determining a relationship between a gray scale gradation and a cutting amount in a photosensitive glass. FIG. 4 is a view showing an example of performing three-dimensional fine processing on the surface of a photosensitive glass plate according to the present invention. FIG. 5 is a diagram showing another example of performing three-dimensional fine processing on the surface of a photosensitive glass plate according to the present invention. FIG. 6 is a diagram showing an example of performing three-dimensional fine processing on the surface of a silicon substrate according to the present invention. [Reference Numerals] P ... pixels 1 ... projection lens system (reduction projection optical system) 2 ... illuminating device 3 ... gantry 11 ... high resolution photographic film 10 ... gray scale mask pattern (original) 20 ... gray scale mask 20 1, 20 2 ... gradient density area 20 3 ... medium density area 20 4 ... relatively high density area 20 5 ... relatively low density area 20 6 ... gradient density area 21 ... photosensitive glass plate 21 '... photosensitive glass Plates 21 1 ′, 21 2 ′, inclined regions 21 3 ′, 21 4 , 21 5 ′, regions of different depths 22, cover glass 23, ultraviolet light 24, silicon substrate 24 6, inclined region 25, photoresist layer 25 ′ ... resist pattern 25 6 '... inclined area
──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. 7 Identification symbol FI Theme coat ゛ (Reference) H01L 21/027 H01L 21/30 502P 505