CN114460819A - Alignment mark for electron beam exposure and preparation method thereof - Google Patents
Alignment mark for electron beam exposure and preparation method thereof Download PDFInfo
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- CN114460819A CN114460819A CN202210042527.5A CN202210042527A CN114460819A CN 114460819 A CN114460819 A CN 114460819A CN 202210042527 A CN202210042527 A CN 202210042527A CN 114460819 A CN114460819 A CN 114460819A
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- 238000002360 preparation method Methods 0.000 title abstract description 11
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- G—PHYSICS
- G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
- G03F—PHOTOMECHANICAL PRODUCTION OF TEXTURED OR PATTERNED SURFACES, e.g. FOR PRINTING, FOR PROCESSING OF SEMICONDUCTOR DEVICES; MATERIALS THEREFOR; ORIGINALS THEREFOR; APPARATUS SPECIALLY ADAPTED THEREFOR
- G03F9/00—Registration or positioning of originals, masks, frames, photographic sheets or textured or patterned surfaces, e.g. automatically
- G03F9/70—Registration or positioning of originals, masks, frames, photographic sheets or textured or patterned surfaces, e.g. automatically for microlithography
- G03F9/7073—Alignment marks and their environment
- G03F9/708—Mark formation
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- G—PHYSICS
- G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
- G03F—PHOTOMECHANICAL PRODUCTION OF TEXTURED OR PATTERNED SURFACES, e.g. FOR PRINTING, FOR PROCESSING OF SEMICONDUCTOR DEVICES; MATERIALS THEREFOR; ORIGINALS THEREFOR; APPARATUS SPECIALLY ADAPTED THEREFOR
- G03F7/00—Photomechanical, e.g. photolithographic, production of textured or patterned surfaces, e.g. printing surfaces; Materials therefor, e.g. comprising photoresists; Apparatus specially adapted therefor
- G03F7/20—Exposure; Apparatus therefor
- G03F7/2051—Exposure without an original mask, e.g. using a programmed deflection of a point source, by scanning, by drawing with a light beam, using an addressed light or corpuscular source
- G03F7/2059—Exposure without an original mask, e.g. using a programmed deflection of a point source, by scanning, by drawing with a light beam, using an addressed light or corpuscular source using a scanning corpuscular radiation beam, e.g. an electron beam
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- G—PHYSICS
- G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
- G03F—PHOTOMECHANICAL PRODUCTION OF TEXTURED OR PATTERNED SURFACES, e.g. FOR PRINTING, FOR PROCESSING OF SEMICONDUCTOR DEVICES; MATERIALS THEREFOR; ORIGINALS THEREFOR; APPARATUS SPECIALLY ADAPTED THEREFOR
- G03F7/00—Photomechanical, e.g. photolithographic, production of textured or patterned surfaces, e.g. printing surfaces; Materials therefor, e.g. comprising photoresists; Apparatus specially adapted therefor
- G03F7/70—Microphotolithographic exposure; Apparatus therefor
- G03F7/70483—Information management; Active and passive control; Testing; Wafer monitoring, e.g. pattern monitoring
- G03F7/70605—Workpiece metrology
- G03F7/70616—Monitoring the printed patterns
- G03F7/70633—Overlay, i.e. relative alignment between patterns printed by separate exposures in different layers, or in the same layer in multiple exposures or stitching
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- G—PHYSICS
- G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
- G03F—PHOTOMECHANICAL PRODUCTION OF TEXTURED OR PATTERNED SURFACES, e.g. FOR PRINTING, FOR PROCESSING OF SEMICONDUCTOR DEVICES; MATERIALS THEREFOR; ORIGINALS THEREFOR; APPARATUS SPECIALLY ADAPTED THEREFOR
- G03F9/00—Registration or positioning of originals, masks, frames, photographic sheets or textured or patterned surfaces, e.g. automatically
- G03F9/70—Registration or positioning of originals, masks, frames, photographic sheets or textured or patterned surfaces, e.g. automatically for microlithography
- G03F9/7073—Alignment marks and their environment
- G03F9/7076—Mark details, e.g. phase grating mark, temporary mark
Abstract
The application provides an alignment mark for electron beam exposure and a preparation method thereof, wherein the preparation method comprises the following steps: covering photoresist on the substrate; exposing and developing the photoresist in a predetermined shape to remove a portion of the photoresist on the substrate, thereby forming a pattern having the predetermined shape; enabling the photoresist remained on the substrate to expand under heat while depositing metal on the substrate and the photoresist remained on the substrate; and removing the photoresist remaining on the substrate and the metal deposited thereon, thereby obtaining the deposited metal having the predetermined shape on the substrate. The technical scheme of the application improves the alignment effect of the alignment mark.
Description
Technical Field
The application relates to the technical field of photoetching, in particular to an alignment mark for electron beam exposure and a preparation method thereof.
Background
Among the processing technologies such as pattern exposure (lithography), material etching, thin film generation, ion implantation, and bonding interconnection, the pattern exposure technology is the major driver of the development of microelectronic fabrication technology, and due to the increasing resolution and alignment precision of the exposed patterns, the integrated circuit integration level and the manufacturing cost are continuously improved. The electron beam exposure technology is a key technology for promoting the development of micro-electronics and micro-nano processing, and especially plays an irreplaceable role in the field of nano manufacturing.
The electron beam exposure is a technique of directly drawing or projecting and copying a pattern on a wafer coated with photosensitive resist by using an electron beam, and is characterized in that the wavelength of the electron beam is very short, the resolution is high (the limit resolution can reach 3-8 nm), the pattern is easy to generate and modify, and the manufacturing period is short. Electron beam exposure is one of the most interesting next-generation lithography technologies due to its high resolution, stable performance, powerful functions and relatively low cost.
In the micro-nano manufacturing of semiconductor devices, the manufacture of one device usually needs to use several or even ten times of electron beam exposure, and factors influencing the process error of the electron beam exposure include the resolution of an electron beam lithography machine and the precision of an electron resist, and also the precision of alignment of overlay between different layers of lithography patterns in the manufacturing process of the device. The overlay accuracy between multiple exposures is often a critical parameter for device performance. In addition, the deflection amplitude of the system electron beam needs to be adjusted to match the size of the write field specifically used, which is the write field calibration. In practical applications, either overlay or write field calibration, is implemented with high quality alignment marks.
Alignment marks are commonly used in electron beam alignment, and generally comprise protrusions or grooves having a cross shape, a circular shape, a square shape, an L shape, or the like, and having a right-angle structure. The alignment marks may be carried by the electron beam exposure system or prepared on the sample substrate. The alignment marks are of various shapes, but only one design principle is used, namely, the alignment marks help an operator or a machine to realize accurate positioning.
The current alignment mark has poor alignment effect and is easy to introduce errors. As shown in fig. 1, in actual scanning electron microscope imaging, during actual field adjustment or alignment, the alignment mark needs to be photographed in the scanning electron microscope, and a two-dimensional photo is formed for manual positioning, so as to accurately position the cross center. Especially after the alignment mark is used many times, the imaging quality becomes worse and it becomes more difficult to find the center.
The statements in this background section merely disclose technology known to the inventors and do not, of course, represent prior art in the art.
Disclosure of Invention
The application aims to provide an alignment mark for electron beam exposure and a preparation method thereof, and solves the problem of accurate positioning of the alignment mark.
According to an aspect of the present application, there is provided a method of preparing an alignment mark for electron beam exposure, including: covering a photoresist on the substrate; exposing and developing the photoresist in a predetermined shape to remove a portion of the photoresist on the substrate, thereby forming a pattern having the predetermined shape; heating and expanding the photoresist remained on the substrate while depositing metal on the substrate and the photoresist remained on the substrate; and removing the photoresist remaining on the substrate and the metal deposited thereon, thereby obtaining the deposited metal having the predetermined shape on the substrate.
According to some embodiments, wherein thermally expanding the photoresist remaining on the substrate comprises:
heating the photoresist remaining on the substrate by energy carried by metal deposited on the substrate and the photoresist remaining on the substrate.
According to some embodiments, wherein the emission source of the metal has a predetermined distance from the substrate.
According to some embodiments, wherein thermally expanding the photoresist remaining on the substrate comprises:
the substrate and/or the photoresist remaining on the substrate are heated using a separate heater.
According to an aspect of the present application, there is provided a method of preparing an alignment mark for electron beam exposure, including: covering a first photoresist on a substrate; covering a second photoresist on the first photoresist; exposing and developing the first photoresist and the second photoresist in a predetermined shape to remove a portion of the first photoresist and a portion of the second photoresist on the substrate, thereby forming a pattern having the predetermined shape; enabling the first photoresist and the second photoresist which are remained on the substrate to expand under heat while depositing metal on the substrate and the second photoresist which is remained on the substrate; and removing the first photoresist and the second photoresist remaining on the substrate and the metal deposited thereon, thereby obtaining a deposited metal having the predetermined shape on the substrate.
According to some embodiments, wherein the first photoresist has a higher sensitivity than the second photoresist, such that after exposure and development, the pattern of the first photoresist is larger than the pattern of the second photoresist.
According to some embodiments, wherein the pattern of the predetermined shape has an inverted trapezoidal structure.
According to some embodiments, wherein thermally expanding the first photoresist and the second photoresist remaining on the substrate comprises: heating the first photoresist and the second photoresist remaining on the substrate by energy carried by metal deposited on the substrate and the second photoresist remaining on the substrate.
According to some embodiments, wherein the emission source of the metal has a predetermined distance from the substrate.
According to some embodiments, wherein thermally expanding the first photoresist and the second photoresist remaining on the substrate comprises:
the substrate and/or the first and second photoresists remaining on the substrate are heated using separate heaters.
According to an aspect of the present application, there is provided an alignment mark for electron beam exposure prepared using the method as described above.
According to some embodiments, wherein the alignment mark has a triangular, trapezoidal or granary-shaped cross-section.
Based on the alignment mark for electron beam exposure and the preparation method thereof, the distance between a metal emission source and a substrate is set to be a preset distance, incident metal atoms contain higher kinetic energy, as a metal material impacts on a photoresist or the substrate, the kinetic energy is transmitted to the photoresist or the substrate, the heat obtained in the deposition process is higher than the heat conducted away by a substrate base, the residual heat enables the photoresist to generate thermal expansion, and during the coating process, the openings of the preset shape of the photoresist are gradually reduced (such as the change trend of the initial stage, the middle stage and the final stage in the figures 2-3), so that the deposited metal film forms a trapezoid shape or a pointed shape; or in the deposition process, the photoresist is heated by the substrate base, so that the photoresist is thermally expanded, and in the coating process, the openings with the preset shapes of the photoresist are gradually reduced (such as the change trend of the initial stage, the middle stage and the final stage in the figures 2-3), so that the deposited metal film forms a trapezoid or a pointed shape, and the reliability of the alignment mark and the alignment accuracy are effectively improved.
For a better understanding of the nature and technical content of the present application, reference should be made to the following detailed description and accompanying drawings, which are provided to illustrate the present application and are not intended to limit the scope of the present application in any way.
Drawings
Embodiments of the present disclosure are described in detail below with reference to the accompanying drawings. The accompanying drawings, which are incorporated herein and constitute part of this disclosure, serve to provide a further understanding of the disclosure. The exemplary embodiments of the present disclosure and their description are provided to explain the present disclosure and not to limit the present disclosure. In the drawings:
fig. 1 shows a schematic diagram of a conventional scanning structure of an electron microscope.
Fig. 2 is a schematic flow chart illustrating the process of preparing an alignment mark from 1 layer of photoresist according to an exemplary embodiment of the present application.
Fig. 3 is a schematic flow chart illustrating a process of preparing an alignment mark from 2 layers of photoresist according to an exemplary embodiment of the present application.
Fig. 4 shows a schematic view of a scanning electron microscope structure according to an exemplary embodiment of the present application.
Detailed Description
In the following, only certain exemplary embodiments are briefly described. As those skilled in the art will recognize, the described embodiments may be modified in various different ways, all without departing from the spirit or scope of the present invention. Accordingly, the drawings and description are to be regarded as illustrative in nature, and not as restrictive.
In the description of the present invention, it is to be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", and the like, indicate orientations and positional relationships based on those shown in the drawings, and are used only for convenience of description and simplicity of description, and do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus, should not be considered as limiting the present invention. Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, features defined as "first", "second", may explicitly or implicitly include one or more of the described features. In the description of the present invention, "a plurality" means two or more unless specifically defined otherwise.
In the description of the present invention, it should be noted that unless otherwise explicitly stated or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, e.g., as meaning either a fixed connection, a removable connection, or an integral connection, either mechanically, electrically, or in communication with each other; either directly or indirectly through intervening media, either internally or in any other relationship. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.
In the present invention, unless otherwise expressly stated or limited, "above" or "below" a first feature means that the first and second features are in direct contact, or that the first and second features are not in direct contact but are in contact with each other via another feature therebetween. Also, the first feature being "on," "above" and "over" the second feature includes the first feature being directly on and obliquely above the second feature, or merely indicating that the first feature is at a higher level than the second feature. A first feature being "under," "below," and "beneath" a second feature includes the first feature being directly above and obliquely above the second feature, or simply meaning that the first feature is at a lesser level than the second feature.
The following disclosure provides many different embodiments or examples for implementing different features of the invention. To simplify the disclosure of the present invention, the components and arrangements of specific examples are described below. Of course, they are merely examples and are not intended to limit the present invention. Furthermore, the present invention may repeat reference numerals and/or letters in the various examples, such repetition is for the purpose of simplicity and clarity and does not in itself dictate a relationship between the various embodiments and/or configurations discussed. In addition, the present invention provides examples of various specific processes and materials, but one of ordinary skill in the art may recognize applications of other processes and/or uses of other materials.
Photoetching is a key process link in the industries of semiconductors, flat panel displays, MEMS, photoelectrons and the like at present. The photolithography technique is a technique for preparing a micro-nano pattern on a substrate by using a photoresist (photoresist) as a medium under the action of short-wavelength light. Taking a semiconductor process as an example, a semiconductor device is completed by various special materials through complicated micro-nano processing flows of photoetching, ion etching, polishing and the like. The photoetching equipment is the most central equipment in the semiconductor process, and the photoetching technology is used in the links of mask preparation, chip manufacturing and packaging.
The types of lithography techniques are divided into two main categories, direct-write lithography and projection lithography. The direct-write lithography is a key link for preparing a micro-nano structure source in a device, and computer design data are prepared on a specific substrate to form a graphic layout of a high-precision micro-nano structure. Direct writing is the direct application of a focused electron beam spot onto a substrate having a surface coated with a photoresist, without the need for the most expensive and time consuming masks of optical lithography. Direct-write lithography is the most common and used technology, and its role in scientific research is becoming more and more widespread with the miniaturization of direct-write electron beam exposure machines.
Laser direct writing and electron beam direct writing are two major direct writing techniques in the industry. The laser direct writing can meet the requirements of preparing node masks of 0.25 micron and above of a semiconductor and preparing partial masks of less than 0.25 micron. About 75% of the total amount of the current semiconductor mask is prepared by a laser direct writing device, and the rest of the mask is finished by an electron beam direct writing device. A large-format mask in the field of flat panel display is 100% prepared by laser direct writing equipment.
The direct-write lithography and the projection lithography are two types of lithography with definite division of labor in the current industry, and the projection lithography has the characteristics of higher line width resolution, higher precision and higher production efficiency. Although direct-write lithography can not meet the requirement of large-scale manufacturing of devices, in the circuit board industry, the trend that laser direct-write replaces a traditional exposure machine is clear, maskless lithography is an ideal target which is always pursued by the industry, the expenditure of expensive masks can be reduced, the development efficiency of new products is improved, and the requirement of small-batch diversified production is met. In addition, direct write lithography has greater flexibility and wide applicability due to its digital nature. An innovative exposure mode can be developed and used as a basic technology of digital micro-nano processing, so that the method is expected to become a key technology for iterative upgrading of processes and innovation of new products in semiconductor and photoelectron related industries.
In the photoetching application field with substrate warping and substrate deformation, the self-adaptive adjustment capability of direct-write photoetching enables the photoetching to have the advantages of high yield and good consistency. With the development of advanced packaging schemes such as FanOut, COF, etc., the packaging lithography technology needs to have smaller line width, larger format, and better capability of pattern alignment overlay.
In the new field of micro-nano photoelectron, the development of ALoT needs the innovative research and development of a large number of photoelectric sensing devices. 3D photoetching and micro-nano manufacturing are novel stone-based technologies of photoelectronic products, and have a plurality of industrial application values, such as 3D perception, augmented reality display, optical sensing devices (such as TOF), ultrathin imaging, three-dimensional display, novel optical films and the like. The micro-nano photonic device is gradually applied to the fields of smart phones, augmented reality AR and vehicles. Different from an integrated circuit graph, the micro-nano photon sensing device requires higher position arrangement precision, longitudinal surface type precision and structural morphology and has the characteristic of dense continuous curved surface morphology. Therefore, the novel 3D direct-write lithography technology realizes the accurate matching of the exposure writing dose and the position morphology, and is an innovative technical path for preparing the grade micro-nano structure morphology of the novel photoelectron sensor.
The preferred embodiments of the present invention will be described below with reference to the accompanying drawings, and it should be understood that the preferred embodiments described herein are merely for purposes of illustrating and explaining the present invention and are not intended to limit the present application.
Example one
Fig. 2 is a schematic flow chart illustrating the process of preparing an alignment mark from 1 layer of photoresist according to an exemplary embodiment of the present application.
As shown in fig. 2, according to an exemplary embodiment of the present application, the present application discloses a method of preparing an alignment mark 10 for electron beam exposure, including: covering a substrate 100 with a photoresist 101; exposing and developing the photoresist 101 in a predetermined shape to remove a portion of the photoresist 101 on the substrate 100, thereby forming a pattern having a predetermined shape; simultaneously depositing metal on a substrate 100 and a photoresist 101 remained on the substrate 100, and enabling the photoresist 101 remained on the substrate 100 to expand by heat; and removing the photoresist 101 remaining on the substrate 100 and the metal deposited thereon, thereby obtaining a deposited metal having a predetermined shape on the substrate 100.
In other words, fig. 2 shows a process flow for preparing the alignment mark 10 of the present application, and the dotted line is a cross-sectional position. The preparation process comprises four steps:
1) firstly, covering a substrate 100 with a photoresist 101;
2) performing exposure of a predetermined pattern of the alignment mark 10 and development, the predetermined pattern being displayed on the photoresist 101;
3) the deposition of the material of the alignment mark 10 is performed, including but not limited to electron beam evaporation, magnetron sputtering, etc., and the material includes metal, such as Ti \ Au, Ti \ Pd, Ni, etc., which have high secondary electron yield, so as to facilitate the imaging of the scanning electron microscope.
4) The substrate 100 covered with the photoresist 101 is immersed in a solution capable of dissolving the photoresist 101, and after a suitable time, the substrate is peeled off to obtain the alignment mark 10. The scanning electron microscope imaging of the alignment mark 10 realized by the preparation process of the application can be seen as shown in fig. 4, and the alignment mark 10 of the application is changed from a planar structure to a three-dimensional structure, so that an auxiliary alignment line appears in the imaging of the scanning electron microscope.
According to the embodiment of the present application, the predetermined shape may be a cross 103, a circle, or a square, and the present application is not particularly limited.
According to the embodiment of the present application, when the predetermined shape is the cross 103, the opening width of the pattern of the predetermined shape is 50nm to 5 μm.
According to the embodiment of the present application, wherein expanding the photoresist 101 remaining on the substrate 100 by heat comprises: the photoresist 101 remaining on the substrate 100 is heated by energy carried by the metal deposited on the substrate 100 and the photoresist 101 remaining on the substrate 100.
According to the embodiment of the present application, the emission source of the metal has a predetermined distance from the substrate 100.
According to an embodiment of the present application, a predetermined distance between the emission source of the metal and the substrate 100 may be set to 20cm to 60 cm.
According to the embodiment of the present application, in the step 3, the distance between the metal emission source and the substrate 100 is set to be a predetermined distance, the incident metal atoms have higher kinetic energy, and as the metal material impinges on the photoresist 101 or the substrate 100, the kinetic energy is transferred to the photoresist 101 or the substrate 100, and the heat obtained during the deposition process is higher than the heat conducted away by the substrate base, so that the residual heat causes the photoresist 101 to thermally expand, and during the coating process, the openings of the predetermined shape of the photoresist 101 gradually decrease (as the variation trend of the initial stage, the middle stage and the final stage in fig. 2), so that the deposited metal film forms a trapezoid or a sharp peak.
According to the embodiment of the present application, wherein expanding the photoresist 101 remaining on the substrate 100 by heat comprises: the substrate 100 and/or the photoresist 101 remaining on the substrate 100 are heated using a separate heater.
According to the embodiment of the present application, in the step 3, the photoresist 101 may also obtain heat by heating the substrate base during the deposition process, so that the photoresist 101 undergoes thermal expansion, and during the coating process, the openings of the predetermined shape of the photoresist 101 are gradually reduced (as shown in the initial, middle and final variation trends in fig. 2), so that the deposited metal film forms a trapezoid or a pointed shape, thereby effectively improving the reliability and the alignment accuracy of the alignment mark 10.
Example two
Fig. 3 is a schematic flow chart illustrating a process of preparing an alignment mark from 2 layers of photoresist according to an exemplary embodiment of the present application. Fig. 4 shows a schematic view of a scanning electron microscope structure according to an exemplary embodiment of the present application.
As shown in fig. 3, according to an aspect of the present application, there is provided a method for preparing an alignment mark 10 for electron beam exposure, including: covering the substrate 100 with a first photoresist 105; covering the first photoresist 105 with a second photoresist 106; exposing and developing the first and second photoresists 105 and 106 in a predetermined shape to remove a portion of the first and second photoresists 105 and 106 on the substrate 100, thereby forming a pattern having a predetermined shape; while depositing metal on the substrate 100 and the second photoresist 106 remaining on the substrate 100, thermally expanding the first photoresist 105 and the second photoresist 106 remaining on the substrate 100; and removing the first and second photoresists 105 and 106 remaining on the substrate 100 and the metal deposited thereon, thereby obtaining a deposited metal having a predetermined shape on the substrate 100.
In other words, fig. 3 shows a process flow for preparing the alignment mark 10 of the present application, and the dotted line is a cross-sectional position. The preparation process comprises four steps:
1) firstly, covering a first photoresist 105 and a second photoresist 106 on a substrate 100, wherein the two photoresists have difference in sensitivity, and the second photoresist 106 with high sensitivity is arranged below the substrate;
2) performing exposure of a predetermined pattern of the alignment mark 10 and development, the predetermined pattern being displayed on the photoresist, and forming the undercut structure shown in the second step, as seen in a cross-sectional view, since the sensitivity of the second photoresist 106 at the bottom is high, the width of the predetermined pattern after development may be larger;
3) the deposition of the material of the alignment mark 10 is performed, including but not limited to electron beam evaporation, magnetron sputtering, etc., and the material includes metal, such as Ti \ Au, Ti \ Pd, Ni, etc., which have high secondary electron yield, so as to facilitate the imaging of the scanning electron microscope.
4) The substrate 100 is immersed in a solution capable of dissolving the photoresist, and after a suitable time, is peeled off to obtain the alignment mark 10. The scanning electron microscope imaging of the alignment mark 10 realized by the process of the present application can be seen, as shown in fig. 4, that the alignment mark 10 of the present application is changed from a planar structure to a three-dimensional structure, so that an auxiliary alignment line appears in the imaging of the scanning electron microscope.
According to the embodiment of the present application, the predetermined shape may be a cross 103, a circle, or a square, and the present application is not particularly limited.
According to the embodiment of the present application, when the predetermined shape is the cross 103, the opening width of the pattern of the predetermined shape on the second photoresist 106 is 50nm to 5 μm.
According to the embodiment of the present application, the first photoresist 105 has a higher sensitivity than the second photoresist 106, so that the pattern of the first photoresist 105 is larger than the pattern of the second photoresist 106 after exposure and development.
According to an embodiment of the present application, the sensitivity of the first photoresist 105 is more than 1.2 times the sensitivity of the second photoresist 106.
According to the embodiment of the present application, the pattern of the predetermined shape has an inverted trapezoidal structure 104.
According to an embodiment of the present application, wherein thermally expanding the first photoresist 105 and the second photoresist 106 remaining on the substrate 100 comprises: the first photoresist 105 and the second photoresist 106 remaining on the substrate 100 are heated by energy carried by the metal deposited on the substrate 100 and the second photoresist 106 remaining on the substrate 100.
According to the embodiment of the present application, there is a predetermined distance between the emission source of the metal and the substrate 100.
According to the embodiment of the present application, a predetermined distance between the emission source of the metal and the substrate 100 may be set to 20cm to 60 cm.
According to the embodiment of the present application, in the step 3, the distance between the metal emission source and the substrate 100 is set to be a predetermined distance, the incident metal atoms have higher kinetic energy, and as the metal material impinges on the photoresist or the substrate 100, the kinetic energy is transferred to the photoresist or the substrate 100, and the heat obtained during the deposition process is higher than the heat conducted away by the substrate base, so that the residual heat causes the photoresist to thermally expand, and during the coating process, the openings of the photoresist with a predetermined shape are gradually reduced (as the initial, middle and final change trends in fig. 3), so that the deposited metal film forms a trapezoid or a pointed shape;
according to an embodiment of the present application, wherein thermally expanding the first photoresist 105 and the second photoresist 106 remaining on the substrate 100 comprises: the substrate 100 and/or the first and second photoresists 105 and 106 remaining on the substrate 100 are heated using separate heaters.
According to the embodiment of the present application, in the step 3, the photoresist may also obtain heat by heating the substrate base during the deposition process, so that the photoresist is thermally expanded, and during the coating process, the openings of the predetermined shape of the photoresist are gradually reduced (as shown in the variation trend of the initial stage, the middle stage and the final stage in fig. 3), so that the deposited metal film forms a trapezoid or a pointed shape, thereby effectively improving the reliability of the alignment mark 10 and the accuracy of the alignment.
According to an aspect of the present application, an alignment mark 10 for electron beam exposure is provided, which is prepared using the above method.
According to the embodiment of the application, the alignment mark 10 has a triangular, trapezoidal or granary-shaped cross section, so that the reliability of the alignment mark 10 and the alignment accuracy are effectively improved.
Finally, it should be noted that: although the present disclosure has been described in detail with reference to the foregoing embodiments, it will be apparent to those skilled in the art that changes may be made in the embodiments and/or equivalents thereof without departing from the spirit and scope of the disclosure. Any modification, equivalent replacement, improvement and the like made within the spirit and principle of the present disclosure should be included in the protection scope of the present disclosure.
Claims (12)
1. A method of preparing an alignment mark for electron beam exposure, comprising:
covering a photoresist on the substrate;
exposing and developing the photoresist in a predetermined shape to remove a portion of the photoresist on the substrate, thereby forming a pattern having the predetermined shape;
enabling the photoresist remained on the substrate to expand under heat while depositing metal on the substrate and the photoresist remained on the substrate; and
and removing the photoresist and the metal deposited on the photoresist remained on the substrate, thereby obtaining the deposited metal with the preset shape on the substrate.
2. The production method according to claim 1, wherein causing a photoresist remaining on the substrate to thermally expand comprises:
heating the photoresist remaining on the substrate by energy carried by metal deposited on the substrate and the photoresist remaining on the substrate.
3. The production method according to claim 2, wherein a predetermined distance is provided between a radiation source of the metal and the substrate.
4. The production method according to claim 1, wherein causing a photoresist remaining on the substrate to thermally expand comprises:
the substrate and/or the photoresist remaining on the substrate are heated using a separate heater.
5. A method of preparing an alignment mark for electron beam exposure, comprising:
covering a first photoresist on a substrate;
covering a second photoresist on the first photoresist;
exposing and developing the first photoresist and the second photoresist in a predetermined shape to remove a portion of the first photoresist and a portion of the second photoresist on the substrate, thereby forming a pattern having the predetermined shape;
enabling the first photoresist and the second photoresist which are remained on the substrate to expand under heat while depositing metal on the substrate and the second photoresist which is remained on the substrate; and
and removing the first photoresist and the second photoresist which remain on the substrate and the metal deposited on the first photoresist and the second photoresist, thereby obtaining the deposited metal with the preset shape on the substrate.
6. The production method according to claim 5, wherein the first photoresist has a higher sensitivity than the second photoresist, so that after exposure and development, the pattern of the first photoresist is larger than that of the second photoresist.
7. The production method according to claim 5, wherein the pattern of the predetermined shape has an inverted trapezoidal structure.
8. The manufacturing method according to claim 5, wherein thermally expanding the first photoresist and the second photoresist remaining on the substrate comprises:
heating the first photoresist and the second photoresist remaining on the substrate by energy carried by metal deposited on the substrate and the second photoresist remaining on the substrate.
9. The production method according to claim 8, wherein a predetermined distance is provided between a radiation source of the metal and the substrate.
10. The manufacturing method according to claim 5, wherein thermally expanding the first photoresist and the second photoresist remaining on the substrate comprises:
the substrate and/or the first and second photoresists remaining on the substrate are heated using separate heaters.
11. An alignment mark for electron beam exposure prepared by the method of any one of claims 1-10.
12. The alignment mark according to claim 11, wherein the alignment mark has a triangular, trapezoidal or granary-shaped cross-section.
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| CN202210042527.5A CN114460819B (en) | 2022-01-14 | 2022-01-14 | Alignment mark for electron beam exposure and preparation method thereof |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN117270339A (en) * | 2023-11-21 | 2023-12-22 | 中国科学院上海微系统与信息技术研究所 | High-precision electron beam overlay mark on insulating substrate and preparation method |
Citations (17)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4379833A (en) * | 1981-12-31 | 1983-04-12 | International Business Machines Corporation | Self-aligned photoresist process |
| JPH01192115A (en) * | 1988-01-28 | 1989-08-02 | Toshiba Corp | Formation of alignment marker |
| US5128283A (en) * | 1988-06-08 | 1992-07-07 | Nec Corporation | Method of forming mask alignment marks |
| JPH07201889A (en) * | 1993-12-10 | 1995-08-04 | Korea Electron Telecommun | Method for manufacturing t-shaped gate by double exposure |
| US6118128A (en) * | 1997-11-26 | 2000-09-12 | Mitsubishi Denki Kabushiki Kaisha | Alignment mark for electron beam lithography |
| CN1502118A (en) * | 2000-09-12 | 2004-06-02 | Boc | Method for selective metal film layer removal using carbon dioxide jet spray |
| CN101207069A (en) * | 2006-12-22 | 2008-06-25 | 中芯国际集成电路制造(上海)有限公司 | Method for forming of via hole |
| CN101350297A (en) * | 2007-07-17 | 2009-01-21 | 中芯国际集成电路制造(上海)有限公司 | Method for manufacturing semiconductor device well |
| CN101452211A (en) * | 2007-11-28 | 2009-06-10 | 上海华虹Nec电子有限公司 | Method for producing photolithography alignment mark |
| CN103456659A (en) * | 2013-08-26 | 2013-12-18 | 中国电子科技集团公司第十三研究所 | Method for manufacturing photoetching registration mark for manufacturing semiconductor device |
| CN103487160A (en) * | 2013-09-27 | 2014-01-01 | 北京理工大学 | Method for manufacturing Pt resistor temperature sensor |
| CN104635432A (en) * | 2015-01-27 | 2015-05-20 | 中国科学院物理研究所 | To-be-exposed substrate for electron beam lithography and method of positioning alignment mark |
| WO2015172505A1 (en) * | 2014-05-15 | 2015-11-19 | 京东方科技集团股份有限公司 | Ion implantation method |
| CN105575789A (en) * | 2015-12-23 | 2016-05-11 | 昆山工研院新型平板显示技术中心有限公司 | Method for patterning thin film |
| CN107331601A (en) * | 2017-06-29 | 2017-11-07 | 苏州苏纳光电有限公司 | The photoresist deposition and method for stripping metal of double exposure |
| WO2021069708A1 (en) * | 2019-10-10 | 2021-04-15 | Merck Patent Gmbh | Positive tone photoresist formulation using crosslinkable siloxane compounds |
| CN113341664A (en) * | 2021-04-13 | 2021-09-03 | 西安电子科技大学广州研究院 | Concave SOI substrate electron beam alignment mark structure and preparation method thereof |
-
2022
- 2022-01-14 CN CN202210042527.5A patent/CN114460819B/en active Active
Patent Citations (17)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4379833A (en) * | 1981-12-31 | 1983-04-12 | International Business Machines Corporation | Self-aligned photoresist process |
| JPH01192115A (en) * | 1988-01-28 | 1989-08-02 | Toshiba Corp | Formation of alignment marker |
| US5128283A (en) * | 1988-06-08 | 1992-07-07 | Nec Corporation | Method of forming mask alignment marks |
| JPH07201889A (en) * | 1993-12-10 | 1995-08-04 | Korea Electron Telecommun | Method for manufacturing t-shaped gate by double exposure |
| US6118128A (en) * | 1997-11-26 | 2000-09-12 | Mitsubishi Denki Kabushiki Kaisha | Alignment mark for electron beam lithography |
| CN1502118A (en) * | 2000-09-12 | 2004-06-02 | Boc | Method for selective metal film layer removal using carbon dioxide jet spray |
| CN101207069A (en) * | 2006-12-22 | 2008-06-25 | 中芯国际集成电路制造(上海)有限公司 | Method for forming of via hole |
| CN101350297A (en) * | 2007-07-17 | 2009-01-21 | 中芯国际集成电路制造(上海)有限公司 | Method for manufacturing semiconductor device well |
| CN101452211A (en) * | 2007-11-28 | 2009-06-10 | 上海华虹Nec电子有限公司 | Method for producing photolithography alignment mark |
| CN103456659A (en) * | 2013-08-26 | 2013-12-18 | 中国电子科技集团公司第十三研究所 | Method for manufacturing photoetching registration mark for manufacturing semiconductor device |
| CN103487160A (en) * | 2013-09-27 | 2014-01-01 | 北京理工大学 | Method for manufacturing Pt resistor temperature sensor |
| WO2015172505A1 (en) * | 2014-05-15 | 2015-11-19 | 京东方科技集团股份有限公司 | Ion implantation method |
| CN104635432A (en) * | 2015-01-27 | 2015-05-20 | 中国科学院物理研究所 | To-be-exposed substrate for electron beam lithography and method of positioning alignment mark |
| CN105575789A (en) * | 2015-12-23 | 2016-05-11 | 昆山工研院新型平板显示技术中心有限公司 | Method for patterning thin film |
| CN107331601A (en) * | 2017-06-29 | 2017-11-07 | 苏州苏纳光电有限公司 | The photoresist deposition and method for stripping metal of double exposure |
| WO2021069708A1 (en) * | 2019-10-10 | 2021-04-15 | Merck Patent Gmbh | Positive tone photoresist formulation using crosslinkable siloxane compounds |
| CN113341664A (en) * | 2021-04-13 | 2021-09-03 | 西安电子科技大学广州研究院 | Concave SOI substrate electron beam alignment mark structure and preparation method thereof |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN117270339A (en) * | 2023-11-21 | 2023-12-22 | 中国科学院上海微系统与信息技术研究所 | High-precision electron beam overlay mark on insulating substrate and preparation method |
| CN117270339B (en) * | 2023-11-21 | 2024-02-27 | 中国科学院上海微系统与信息技术研究所 | High-precision electron beam overlay mark on insulating substrate and preparation method |
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|---|---|
| CN114460819B (en) | 2024-01-26 |
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