CN106970437A - The preparation method of reflective gratings based on ultraviolet photolithographic technology - Google Patents
The preparation method of reflective gratings based on ultraviolet photolithographic technology Download PDFInfo
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- CN106970437A CN106970437A CN201710321577.6A CN201710321577A CN106970437A CN 106970437 A CN106970437 A CN 106970437A CN 201710321577 A CN201710321577 A CN 201710321577A CN 106970437 A CN106970437 A CN 106970437A
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- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B5/00—Optical elements other than lenses
- G02B5/18—Diffraction gratings
- G02B5/1847—Manufacturing methods
- G02B5/1857—Manufacturing methods using exposure or etching means, e.g. holography, photolithography, exposure to electron or ion beams
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- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B5/00—Optical elements other than lenses
- G02B5/18—Diffraction gratings
- G02B5/1847—Manufacturing methods
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- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B5/00—Optical elements other than lenses
- G02B5/18—Diffraction gratings
- G02B5/1861—Reflection gratings characterised by their structure, e.g. step profile, contours of substrate or grooves, pitch variations, materials
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Abstract
The invention discloses a kind of preparation method of the reflective gratings based on ultraviolet photolithographic technology, it is a kind of efficient, high accuracy, high-resolution preparing grating method, the grating is using silica as substrate, multiple parallel wedge-shaped reflective faces are provided with substrate, whole grating surface is silver-plated, to improve reflecting effect.It is main in manufacturing process to apply inclination photoetching to make wedge-shaped reflecting surface, by controlling the size and shape of mask plate to make the grating device of arbitrary dimension.What is produced due to single is large-scale grating, sheet gration can be obtained into by cutting, so as to reach the benefit of monolithic grating.Meanwhile, Ultraviolet lithography will not produce ghost line and satellite line, in the absence of the microcosmic irregular or veining defect of ruled grating cutting.Even if occurring in that these defects in process, unqualified discarding can also be retained qualified grating and be dispatched from the factory in quality testing below.
Description
Technical field
The present invention relates to a kind of diffraction grating preparation method, more particularly to a kind of reflecting light based on ultraviolet photolithographic technology
The preparation method of grid, belongs to optical element technology field.
Background technology
Reflective gratings are a kind of common spectroscopic instruments, and application field is than wide.Reflective gratings are that white light is anti-
Penetrate, by interference and diffraction, by optical dispersion, so that complex light is decomposed into spectrum.
Traditional preparing grating mode has mechanical scratching, and photoelectricity delineation is replicated, holographic delineates four kinds, above method
It is all very high to required precision, and a sheet gration can only be once processed, processing cost and cycle are all very high.
From after the birth of nineteen sixty photoetching process, photoetching occupies definitely in the field such as IC manufacturing and MEMS
Status, the requirement with semiconductor to performance constantly lifts, and lithographic accuracy also more and more higher, cost is also more and more lower, allows light
Lithography is applied in preparing grating and is possibly realized.
The content of the invention
The technical problems to be solved by the invention are to provide a kind of making of the reflective gratings based on ultraviolet photolithographic technology
Method, this method is a kind of efficient, and high-precision reflecting light grid preparation method passes through ultraviolet photolithographic technology so that made
Journey is simple, and single batch output rises, and reduces the requirement to plant equipment.
The present invention uses following technical scheme to solve above-mentioned technical problem：
The present invention provides a kind of preparation method of the reflective gratings based on ultraviolet photolithographic technology, the reflective gratings bag
The N number of wedge-shaped raster unit for including silica substrate and being set in substrate, and order is 1 to wedge-shaped raster unit numbering,
2,…,N；Wherein, the reflective face width of single wedge-shaped raster unit is that a, grating constant are that d, inclination angle are β, summit away from substrate
A height of m, summit to substrate vertical line vertical point to inclination angle summit distance be b；
The preparation method of the reflective gratings includes step in detail below：
Step 1, silica substrate is prepared；
Step 2, first time ultraviolet photolithographic：It is uniformly coated with substrate after the photoresist that thickness is m, by substrate by horizontal
State is tiltedUltraviolet photolithographic is carried out after angle, n wedge-shaped impression is formed, wherein,N is that numbering is odd number
Wedge-shaped raster unit number；
Step 3, silica is splashed into for the first time：The substrate that step 2 photoetching is completed tilts β angles by horizontality,
Silica is splashed into the wedge-shaped impression formed under Action of Gravity Field to step 2 respectively, all wedge-shaped light that numbering is odd number are formed
Grid unit；
Step 4, the photoresist in substrate is removed；
Step 5, second of ultraviolet photolithographic：It is uniformly coated with substrate after the photoresist that thickness is m, by substrate by horizontal
State is tiltedUltraviolet photolithographic is carried out after angle, n' wedge-shaped impression is formed, wherein, n' is the wedge-shaped grating list that numbering is even number
First number；
Step 6, silica is splashed into for the second time：The substrate that step 5 photoetching is completed tilts β angles by horizontality,
Silica is splashed into the wedge-shaped impression formed under Action of Gravity Field to step 5 respectively, all wedge-shaped light that numbering is even number are formed
Grid unit；
Step 7, the photoresist in substrate is removed；
Step 8, silver-plated on the grating delineated and dicing.
As the further technical scheme of the present invention, the preparation method also includes carrying out matter to the finished product grating of dicing
Amount detection, and to detecting that underproof product is cut again.
As the further technical scheme of the present invention, the transparent area and shading sector width of mask plate are cdsin α,
Wherein, c is minification of the ultraviolet pattern after lens.
As the further technical scheme of the present invention, the position of mask plate during relative to first time ultraviolet photolithographic, second
Mask plate moves the order of magnitude of a line width in the vertical direction of groove during ultraviolet photolithographic, that is, moves cdsin
α。
As the further technical scheme of the present invention, silica is splashed into for the first time and for the second time and is completed under vacuo.
As the further technical scheme of the present invention, the photoresist in substrate is removed for the first time and for the second time in cooling
Afterwards.
As the further technical scheme of the present invention, the silica substrate prepared in step 1 is circle.
The present invention uses above technical scheme compared with prior art, with following technique effect：
1st, mechanical equipment requirements are declined, this new preparing grating method based on ultraviolet photolithographic technology, it is only necessary to
Need to use common mechanical cutter device in last cutting step, without using hi-precision cutting when producing grating fringe
Equipment, reduces the requirement to mechanical device；
2nd, grating final product quality is high, compared to replica, and the grating that this method makes is entirely former quarter grating, can pole
The quality of grating finished product is improved in big degree, it is ensured that the resolution ratio of product；
3rd, single production yields is high, and existing all grating processing methods are all that same equipment can only be to a piece of less
Grating is processed, in replica method, and one block of former grating of carving can only once produce a piece of replica；What mechanical scratching was processed
Raster size is strictly controlled, and the method based on ultraviolet photolithographic technology can once produce large-scale lenticular lenses, then by cutting
The a large amount of gratings of acquisition are cut, so as to improve overall yield；Although holographic delineation can produce large-scale grating, special to technical requirements
It is not high；
4th, with short production cycle, in addition to replica, remaining traditional preparing grating method can only once delineate one
Groove, it is therefore desirable to take a long time to produce a small amount of grating, overall time cost is high.Remove and be based on ultraviolet photolithographic technology
Preparing grating method Twi-lithography, be splashed into after can just produce all grooves, substantially increase production efficiency；
5th, grating resolution is high, has in preparing grating method, the groove of mechanical scratching and photoelectricity delineation be up to 1000/
Mm, the groove of holographic technology is about 4000/mm, that is to say, that existing preparing grating method wall scroll groove is most narrow about
For 250nm, the preparing grating method based on ultraviolet photolithographic can then reach that 180nm is even lower；
6th, very thin grating can be made：To the pressure of lenticular lenses during due to traditional mechanical scratching and photoelectricity delineation processing
Can be very big, be easy to damage if substrate is excessively thin, in process not into grating, and based on the grating of ultraviolet photolithographic technology
Preparation method is to substrate almost without pressure or directly destruction, therefore can process very thin grating；
7th, production cost is low：With the progress of photoetching process, the cost of photoetching is also more and more lower, and existing maturation process is
Through having reached 40nm and 28nm, and preparing grating only needs to the other photoetching of submicron order, therefore production cost is not high.
Brief description of the drawings
Fig. 1 is the sectional view of whole grating.
Fig. 2 is the sectional view in single wedge-shaped reflective face.
Fig. 3 is sectional view when most starting to coat photoresist.
Sectional view when Fig. 4 is first time ultraviolet photolithographic.
Fig. 5 is the sectional view after first time ultraviolet photolithographic.
Fig. 6 is sectional view when being splashed into silica for the first time.
Fig. 7 is to be splashed into the sectional view after silica for the first time.
Fig. 8 is sectional view when coating photoresist for the second time.
Sectional view when Fig. 9 is second of ultraviolet photolithographic.
Sectional view during Figure 10 after second of ultraviolet photolithographic.
Figure 11 is sectional view when being splashed into silica for the second time.
Figure 12 is to be splashed into the sectional view after silica for the second time.
Figure 13 is the sectional view after electroplate.
Embodiment
Below in conjunction with the accompanying drawings and specific embodiment is described in further detail to technical scheme：
The reflecting light grid preparation method based on ultraviolet photolithographic technology of the present invention is a kind of new, efficient, high accuracy, height
The reflecting light grid preparation method of resolution ratio.The grating is provided with multiple parallel wedge shapes using silica as substrate in substrate
Reflecting surface, whole grating surface is silver-plated, to improve reflecting effect.This preparing grating method application tilts photoetching and is splashed into dioxy
SiClx makes wedge-shaped reflecting surface, therefore independent of high-precision scoring apparatus；Delineate a plurality of simultaneously by way of ultraviolet photolithographic
Groove, can greatly reduce the production cycle；And this preparation method can make the groove that width is below 180nm, therefore
The grating resolution produced is very high；This preparation method can also produce the grating of arbitrary dimension, then be obtained by cutting
Into sheet gration, so as to improve overall yield.
The reflective gratings that the present invention makes include silica substrate and the N number of wedge-shaped grating list set in substrate
Member, as shown in figure 1, order is 1,2 to wedge-shaped raster unit numbering ..., N.As shown in Fig. 2 single wedge-shaped raster unit is anti-
Penetrate formula face width be a, grating constant be d, inclination angle be β, summit away from a height of m of substrate, summit to substrate vertical line vertical point to inclination angle
The distance on summit is b.
The preparation method of reflective gratings as shown in Figure 1 based on ultraviolet photolithographic technology is：
1) silica substrate is prepared：Single crystal-like Silicon Wafer preparation method, but material uses silica, base
Bottom requires surfacing, and high purity, preferably circular piece can be more uniformly distributed when such resist coating.
2) as shown in figure 3, being uniformly coated with the photoresist that thickness is m in the silica substrate produced, m is that grating is high
Degree.
3) first time photoetching：As shown in figure 4, the silica substrate after gluing is tilted by horizontalityAfter angle
Carry out ultraviolet photolithographic,Transparent area and shading sector width are cdsin α, d on mask
For grating constant, c is minification of the ultraviolet pattern after lens, and the substrate section that photoetching terminates is as shown in Figure 5.
4) silica is splashed into for the first time：As shown in fig. 6, the substrate that first time photoetching is completed tilts β by horizontality
Angle,Silica is splashed into groove in a vacuum, the silica being splashed into will be formed under gravity
The reflective face of wedge shape.
5) removed photoresist after cooling down, all wedge-shaped raster units that numbering is odd number are made, now the section of substrate such as Fig. 7 institutes
Show.
6) as shown in figure 8, coating the photoresist that thickness is m again to the substrate in 5).
7) second of photoetching：As shown in figure 9, substrate is tilted by horizontalityUltraviolet photolithographic is carried out after angle.This
When the order of magnitude of a line width is moved in the vertical direction of groove, that is, is moved compared to the first time photoetching in 3), mask
Dynamic cdsin α, the section after photoetching terminates is as shown in Figure 10.
8) silica is splashed into for the second time：As shown in figure 11, the substrate second of photoetching completed tilts β by horizontality
Angle, is splashed into silica into groove in a vacuum, and it is reflective that the silica being splashed into will form wedge shape under gravity
Face.
9) removed photoresist after cooling down, all wedge-shaped raster units that numbering is even number are made, now the section of substrate such as Figure 12 institutes
Show.
10) it is silver-plated on the grating delineated, as shown in figure 13.
11) dicing, quality testing is carried out to finished product grating, and qualified grating directly dispatches from the factory, and underproof product exists
Checking will be cut after underproof part again, and the right rail of acquisition can also dispatch from the factory.
Processing method with above manufacturing process is the reflective gratings based on ultraviolet photolithographic technology for being considered as the present invention
Preparation method.During the preparing grating of the present invention, mainly apply inclination photoetching to make wedge-shaped reflecting surface, covered by control
The size and shape of template can make the grating device of arbitrary dimension.What is produced due to single is large-scale grating, can
To obtain into sheet gration by cutting, so as to reach the benefit of monolithic grating.Meanwhile, Ultraviolet lithography will not produce ghost
Line and satellite line, in the absence of the microcosmic irregular or veining defect of ruled grating cutting.Even if occurring in that this in process
A little defects, unqualified discarding in quality testing below can also be retained qualified grating and dispatched from the factory.
It is described above, it is only the embodiment in the present invention, but protection scope of the present invention is not limited thereto, and appoints
What be familiar with the people of the technology disclosed herein technical scope in, it will be appreciated that the conversion or replacement expected, should all cover
Within the scope of the present invention, therefore, protection scope of the present invention should be defined by the protection domain of claims.
Claims (7)
1. the preparation method of the reflective gratings based on ultraviolet photolithographic technology, it is characterised in that the reflective gratings include two
Oxidation silicon base and the N number of wedge-shaped raster unit set in substrate, and order is 1,2 to wedge-shaped raster unit numbering ...,
N；Wherein, the reflective face width of single wedge-shaped raster unit be a, grating constant be d, inclination angle be β, summit away from a height of m of substrate,
Summit to substrate vertical line vertical point to inclination angle summit distance be b；
The preparation method of the reflective gratings includes step in detail below：
Step 1, silica substrate is prepared；
Step 2, first time ultraviolet photolithographic：It is uniformly coated with substrate after the photoresist that thickness is m, substrate is inclined by horizontality
TiltedlyUltraviolet photolithographic is carried out after angle, n wedge-shaped impression is formed, wherein,N is the wedge that numbering is odd number
Shape raster unit number；
Step 3, silica is splashed into for the first time：The substrate that step 2 photoetching is completed tilts β angles by horizontality, in gravity
Silica is splashed into the wedge-shaped impression formed under effect to step 2 respectively, all wedge-shaped grating lists that numbering is odd number are formed
Member；
Step 4, the photoresist in substrate is removed；
Step 5, second of ultraviolet photolithographic：It is uniformly coated with substrate after the photoresist that thickness is m, substrate is inclined by horizontality
TiltedlyUltraviolet photolithographic is carried out after angle, n' wedge-shaped impression is formed, wherein, n' is the wedge-shaped raster unit that numbering is even number
Number；
Step 6, silica is splashed into for the second time：The substrate that step 5 photoetching is completed tilts β angles by horizontality, in gravity
Silica is splashed into the wedge-shaped impression formed under effect to step 5 respectively, all wedge-shaped grating lists that numbering is even number are formed
Member；
Step 7, the photoresist in substrate is removed；
Step 8, silver-plated on the grating delineated and dicing.
2. the preparation method of the reflective gratings according to claim 1 based on ultraviolet photolithographic technology, it is characterised in that should
Preparation method also includes carrying out the finished product grating of dicing quality testing, and to detecting that underproof product is cut again
Cut.
3. the preparation method of the reflective gratings according to claim 1 based on ultraviolet photolithographic technology, it is characterised in that cover
The transparent area and shading sector width of film version are cdsin α, wherein, c is minification of the ultraviolet pattern after lens.
4. the preparation method of the reflective gratings according to claim 3 based on ultraviolet photolithographic technology, it is characterised in that phase
The position of mask plate during for first time ultraviolet photolithographic, mask plate is moved in the vertical direction of groove during second of ultraviolet photolithographic
The order of magnitude of one line width, that is, move cdsin α.
5. the preparation method of the reflective gratings according to claim 1 based on ultraviolet photolithographic technology, it is characterised in that the
Silica once and is for the second time splashed into complete under vacuo.
6. the preparation method of the reflective gratings according to claim 1 based on ultraviolet photolithographic technology, it is characterised in that the
The photoresist once removed with second in substrate is after cooling.
7. the preparation method of the reflective gratings according to claim 1 based on ultraviolet photolithographic technology, it is characterised in that step
The silica substrate prepared in rapid 1 is circle.
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110082847A (en) * | 2019-04-29 | 2019-08-02 | 重庆大学 | A kind of preparation method of silicon substrate MEMS balzed grating, |
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| US20020127497A1 (en) * | 1998-09-10 | 2002-09-12 | Brown Daniel J. W. | Large diffraction grating for gas discharge laser |
| JP2003162831A (en) * | 2001-11-27 | 2003-06-06 | Sharp Corp | Optical pickup |
| JP2003227912A (en) * | 2002-02-04 | 2003-08-15 | Nikon Corp | Diffraction optical element |
| US20090273841A1 (en) * | 2002-02-04 | 2009-11-05 | Nikon Corporation | Diffractive optical element and method for manufacturing same |
| CN102540302A (en) * | 2012-02-16 | 2012-07-04 | 苏州大学 | Manufacturing method of convex blazed grating |
| CN103901520A (en) * | 2014-04-23 | 2014-07-02 | 中国科学技术大学 | Method for manufacturing triangular groove echelon gratings with 90-degree vertex angles |
| CN105914180A (en) * | 2016-05-18 | 2016-08-31 | 中国电子科技集团公司第四十研究所 | Method of making reinforced metal hole |
| CN106154382A (en) * | 2016-08-18 | 2016-11-23 | 中国科学技术大学 | There is the preparation method of the heavy caliber thin film diffraction element of high-diffraction efficiency |
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2017
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Patent Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20020127497A1 (en) * | 1998-09-10 | 2002-09-12 | Brown Daniel J. W. | Large diffraction grating for gas discharge laser |
| JP2003162831A (en) * | 2001-11-27 | 2003-06-06 | Sharp Corp | Optical pickup |
| JP2003227912A (en) * | 2002-02-04 | 2003-08-15 | Nikon Corp | Diffraction optical element |
| US20090273841A1 (en) * | 2002-02-04 | 2009-11-05 | Nikon Corporation | Diffractive optical element and method for manufacturing same |
| CN102540302A (en) * | 2012-02-16 | 2012-07-04 | 苏州大学 | Manufacturing method of convex blazed grating |
| CN103901520A (en) * | 2014-04-23 | 2014-07-02 | 中国科学技术大学 | Method for manufacturing triangular groove echelon gratings with 90-degree vertex angles |
| CN105914180A (en) * | 2016-05-18 | 2016-08-31 | 中国电子科技集团公司第四十研究所 | Method of making reinforced metal hole |
| CN106154382A (en) * | 2016-08-18 | 2016-11-23 | 中国科学技术大学 | There is the preparation method of the heavy caliber thin film diffraction element of high-diffraction efficiency |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110082847A (en) * | 2019-04-29 | 2019-08-02 | 重庆大学 | A kind of preparation method of silicon substrate MEMS balzed grating, |
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