CN115440585A - Metal nanostructure and ion beam etching processing method thereof - Google Patents
Metal nanostructure and ion beam etching processing method thereof Download PDFInfo
- Publication number
- CN115440585A CN115440585A CN202211076513.1A CN202211076513A CN115440585A CN 115440585 A CN115440585 A CN 115440585A CN 202211076513 A CN202211076513 A CN 202211076513A CN 115440585 A CN115440585 A CN 115440585A
- Authority
- CN
- China
- Prior art keywords
- etching
- metal
- ion beam
- photoresist
- nano
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Images
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
- H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
- H01L21/04—Manufacture or treatment of semiconductor devices or of parts thereof the devices having at least one potential-jump barrier or surface barrier, e.g. PN junction, depletion layer or carrier concentration layer
- H01L21/18—Manufacture or treatment of semiconductor devices or of parts thereof the devices having at least one potential-jump barrier or surface barrier, e.g. PN junction, depletion layer or carrier concentration layer the devices having semiconductor bodies comprising elements of Group IV of the Periodic System or AIIIBV compounds with or without impurities, e.g. doping materials
- H01L21/30—Treatment of semiconductor bodies using processes or apparatus not provided for in groups H01L21/20 - H01L21/26
- H01L21/31—Treatment of semiconductor bodies using processes or apparatus not provided for in groups H01L21/20 - H01L21/26 to form insulating layers thereon, e.g. for masking or by using photolithographic techniques; After treatment of these layers; Selection of materials for these layers
- H01L21/3205—Deposition of non-insulating-, e.g. conductive- or resistive-, layers on insulating layers; After-treatment of these layers
- H01L21/321—After treatment
- H01L21/3213—Physical or chemical etching of the layers, e.g. to produce a patterned layer from a pre-deposited extensive layer
- H01L21/32139—Physical or chemical etching of the layers, e.g. to produce a patterned layer from a pre-deposited extensive layer using masks
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
- H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
- H01L21/04—Manufacture or treatment of semiconductor devices or of parts thereof the devices having at least one potential-jump barrier or surface barrier, e.g. PN junction, depletion layer or carrier concentration layer
- H01L21/18—Manufacture or treatment of semiconductor devices or of parts thereof the devices having at least one potential-jump barrier or surface barrier, e.g. PN junction, depletion layer or carrier concentration layer the devices having semiconductor bodies comprising elements of Group IV of the Periodic System or AIIIBV compounds with or without impurities, e.g. doping materials
- H01L21/30—Treatment of semiconductor bodies using processes or apparatus not provided for in groups H01L21/20 - H01L21/26
- H01L21/302—Treatment of semiconductor bodies using processes or apparatus not provided for in groups H01L21/20 - H01L21/26 to change their surface-physical characteristics or shape, e.g. etching, polishing, cutting
- H01L21/306—Chemical or electrical treatment, e.g. electrolytic etching
- H01L21/3065—Plasma etching; Reactive-ion etching
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
- H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
- H01L21/04—Manufacture or treatment of semiconductor devices or of parts thereof the devices having at least one potential-jump barrier or surface barrier, e.g. PN junction, depletion layer or carrier concentration layer
- H01L21/18—Manufacture or treatment of semiconductor devices or of parts thereof the devices having at least one potential-jump barrier or surface barrier, e.g. PN junction, depletion layer or carrier concentration layer the devices having semiconductor bodies comprising elements of Group IV of the Periodic System or AIIIBV compounds with or without impurities, e.g. doping materials
- H01L21/30—Treatment of semiconductor bodies using processes or apparatus not provided for in groups H01L21/20 - H01L21/26
- H01L21/302—Treatment of semiconductor bodies using processes or apparatus not provided for in groups H01L21/20 - H01L21/26 to change their surface-physical characteristics or shape, e.g. etching, polishing, cutting
- H01L21/306—Chemical or electrical treatment, e.g. electrolytic etching
- H01L21/308—Chemical or electrical treatment, e.g. electrolytic etching using masks
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
- H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
- H01L21/04—Manufacture or treatment of semiconductor devices or of parts thereof the devices having at least one potential-jump barrier or surface barrier, e.g. PN junction, depletion layer or carrier concentration layer
- H01L21/18—Manufacture or treatment of semiconductor devices or of parts thereof the devices having at least one potential-jump barrier or surface barrier, e.g. PN junction, depletion layer or carrier concentration layer the devices having semiconductor bodies comprising elements of Group IV of the Periodic System or AIIIBV compounds with or without impurities, e.g. doping materials
- H01L21/30—Treatment of semiconductor bodies using processes or apparatus not provided for in groups H01L21/20 - H01L21/26
- H01L21/31—Treatment of semiconductor bodies using processes or apparatus not provided for in groups H01L21/20 - H01L21/26 to form insulating layers thereon, e.g. for masking or by using photolithographic techniques; After treatment of these layers; Selection of materials for these layers
- H01L21/3205—Deposition of non-insulating-, e.g. conductive- or resistive-, layers on insulating layers; After-treatment of these layers
- H01L21/321—After treatment
- H01L21/3213—Physical or chemical etching of the layers, e.g. to produce a patterned layer from a pre-deposited extensive layer
- H01L21/32133—Physical or chemical etching of the layers, e.g. to produce a patterned layer from a pre-deposited extensive layer by chemical means only
- H01L21/32135—Physical or chemical etching of the layers, e.g. to produce a patterned layer from a pre-deposited extensive layer by chemical means only by vapour etching only
- H01L21/32136—Physical or chemical etching of the layers, e.g. to produce a patterned layer from a pre-deposited extensive layer by chemical means only by vapour etching only using plasmas
Landscapes
- Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Microelectronics & Electronic Packaging (AREA)
- General Physics & Mathematics (AREA)
- Manufacturing & Machinery (AREA)
- Computer Hardware Design (AREA)
- Condensed Matter Physics & Semiconductors (AREA)
- Power Engineering (AREA)
- Plasma & Fusion (AREA)
- Chemical & Material Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- General Chemical & Material Sciences (AREA)
- Drying Of Semiconductors (AREA)
Abstract
The present disclosure provides a method of processing a metal nanostructure using ion beam etching, the method comprising: s1, placing a sample to be processed in ion beam etching equipment, wherein the sample to be processed sequentially comprises a substrate, a metal film layer and a photoresist nano pattern layer from bottom to top, and the photoresist nano pattern layer is exposed out of an etching area of the metal film layer; s2, etching the etching area of the metal film layer by using ion beams, wherein the etching time is a first time length t 1 (ii) a S3, intermittent ion beam etching is carried out, and the intermittent time is a second duration t 2 (ii) a S4, repeating S2-S3 until the etching depth reaches the target thickness; and S5, removing the photoresist nano pattern layer to obtain the target metal nano structure. The method can improve the collimation of the ion beam and reduce the temperature rise effect caused by the ion beam etching, thereby improving the etching precision and etchingThe quality of the pattern.
Description
Technical Field
The disclosure relates to the technical field of semiconductor processing, in particular to a metal nanostructure and an ion beam etching processing method thereof.
Background
The development of nano devices has increasingly strict requirements on Critical Dimension (CD) of nano structures. The processing of metal nanostructures plays an important role in semiconductor processes and plasma nanophotonics devices. In semiconductor processing, chromium (Cr) metal films are commonly used as the absorber layer of reticles due to their physical and chemical stability, long lifetime, and high contrast. In a plasma nano-optical device, precious metal nanostructures such as gold (Au) and silver (Ag) are applied to sensing and detection and generation of special optical properties due to their strong light-substance interaction characteristics. For the etching of the patterns on the metal layers such as the Cr layer, the dry etching and the wet etching are available. The wet etching is to soak the sample in a chemical etchant, and the etchant etches the metal material exposed in the photoresist opening pattern. The characteristic of wet etching is isotropy, and the method is mainly used for etching micron-scale patterns. But dry etching is one of the main methods for etching patterns below micrometers.
At present, reactive ion etching is mainly adopted for etching a metal layer in a large-scale integrated circuit process. In reactive ion etching, the chemical gas of glow discharge and the metal film undergo a strong chemical reaction, which produces an etching effect on the exposed diaphragm. The reactive ion beam etching has ideal etching rate and selectivity and higher etching precision. However, in the process of reactive ion etching of the metal film structure, gases with extremely high toxicity, such as chlorine gas or chlorine-based gas, are often used as reaction gases, which have strict requirements on laboratory conditions, gas storage and treatment, and it is difficult for a general laboratory to satisfy the conditions for using these toxic gases.
The ion beam etching decomposes argon into argon ions by using a glow discharge principle, and the argon ions physically bombard the surface of a sample through the acceleration of an anode electric field so as to achieve the etching effect. The ion beam with certain energy enters the working chamber and is shot to the surface of the solid to bombard the atoms on the surface of the solid, so that the material atoms are sputtered to achieve the purpose of etching, and the method belongs to pure physical etching. The ion beam etching has the characteristics of good directionality, no undercutting and high steepness, and the line width CD of an etched pattern can be less than 100nm.
Although the ion beam etch rate is much lower than reactive ion beam etching, the selectivity is also inferior to reactive ion beam etching. For the etching of a metal film layer with the thickness of dozens of nanometers, the ion beam etching does not need toxic reaction gas, so the requirement on the laboratory condition is lower. The etching depth of the ion beam is positively correlated with the etching time. For a metal film with the thickness of tens of nanometers, the etching can be completed within 1 to 3 minutes usually, and the time is relatively fast. Therefore, in a general laboratory, the ion beam etching method is widely used in metal nanofabrication. However, during the ion beam etching process, the argon ion beam bombards the sputtering ions and gases generated on the surface of the metal film, which can affect the collimation of the ion beam and the energy reaching the surface of the sample; on the other hand, the sample can generate heat effect in the etching process, which can also affect the etching resistance of the photoresist and the etching precision of the chromium film layer.
Therefore, the conventional method can etch the metal film layer with a precision of usually more than 100nm, which is a challenge for etching patterns below 100nm and even below 50nm.
Disclosure of Invention
Technical problem to be solved
In order to solve the problems, the disclosure provides a metal nanostructure and an ion beam etching processing method thereof, which are used for solving the technical problems of low etching precision and the like of the traditional ion beam etching method.
(II) technical scheme
One aspect of the present disclosure provides a method of processing a metal nanostructure using ion beam etching, including: s1, placing a sample to be processed in ion beam etching equipment, wherein the sample to be processed sequentially comprises a substrate, a metal film layer and a photoresist nano pattern layer from bottom to top, and the photoresist nano pattern layer is exposed out of an etching area of the metal film layer; s2, etching the etching area of the metal film layer by using ion beams, wherein the etching time is a first time length t 1 (ii) a S3, intermittent ion beam etchingThe intermittent time is a second time length t 2 (ii) a S4, repeating S2-S3 until the etching depth reaches the target thickness; and S5, removing the photoresist nano pattern layer to obtain the target metal nano structure.
Further, S1 further includes preparing a sample to be processed, including: s11, cleaning the substrate; s12, depositing a layer of metal on the surface of the substrate to obtain a metal film layer; and S13, coating photoresist on the metal film layer, and exposing and developing to obtain the photoresist nano pattern layer.
Further, before S12, the method further includes: and depositing an adhesion-promoting layer on the surface of the substrate to improve the adhesion between the substrate and the metal film layer.
Further, the substrate in S11 includes one of quartz, a silicon wafer, and sapphire; the metal in S12 comprises one of chromium, gold and silver; the photoresist in S13 includes a positive photoresist or a negative photoresist.
Further, the first time period t in S2 1 In the range of 5s ≤ t 1 Less than or equal to 250s; second duration t in S3 2 In the range of 5s ≤ t 2 Less than or equal to 250s; and t is 2 ≥t 1 。
Further, the number of times of repeating S2 to S3 in S4 is more than 3.
Further, the removing the photoresist nanopattern layer in S5 includes: s51, removing the photoresist nano pattern layer by using oxygen plasma; and S52, cleaning the sample to be processed by a wet method to obtain the target metal nano structure.
Further, the target metal nanostructure obtained in S5 includes one of a metal nano round hole, a metal nano square hole, a metal nano groove, a metal nano gap, and a metal nano lattice; the characteristic size range of the metal nano structure is 5 nm-100 nm.
Another aspect of the present disclosure provides a metal nanostructure processed according to the foregoing method for processing a metal nanostructure using ion beam etching.
In still another aspect, the present disclosure provides an application of the method for processing a metal nanostructure by ion beam etching in uv lithography chrome mask processing, metal plasma nanostructure processing, metal nano antenna processing, and super surface processing.
(III) advantageous effects
According to the metal nanostructure and the ion beam etching processing method thereof, on one hand, by adopting an intermittent etching method of etching a first time length and an intermittent etching second time length by using the ion beam, in the intermittent time of each etching, the vacuum degree in an ion beam etching cavity is recovered, the collimation of the ion beam is improved, and the energy loss when the ion beam reaches the surface of a sample is reduced; meanwhile, the temperature rise effect caused by ion beam etching is reduced, the photoresist deformation on the surface of the metal film layer is reduced, and the etching resistance is improved, so that the etching precision and the quality of an etched pattern are improved, and the etching of a metal nano structure with the characteristic dimension of 100nm or even below 50nm can be realized. On the other hand, the method disclosed by the invention is simple to operate, and can realize the processing of the metal nano structure with high resolution and high quality by only regulating and controlling the etching method without using toxic reaction gas.
Drawings
FIG. 1 schematically illustrates a flow chart of a method for processing metallic nanostructures using ion beam etching, in accordance with an embodiment of the present disclosure;
FIG. 2 schematically illustrates an etch time-power diagram of an intermittent etch process according to an embodiment of the disclosure;
FIG. 3 is a schematic diagram illustrating a structure of a sample to be processed in a batch etching method according to an embodiment of the present disclosure;
FIG. 4 schematically illustrates a pressure variation in a chamber during an etch cycle in accordance with an embodiment of the present disclosure;
fig. 5a and 5b are scanning electron microscope images schematically illustrating the pattern structures with different sizes and different shapes etched on the Cr film according to the present embodiment 1 of the present disclosure;
FIGS. 6a and 6b are scanning electron microscope images schematically illustrating Cr lithography mask grating patterns processed according to embodiment 2 of the present disclosure;
FIGS. 7a and 7b are scanning electron micrographs schematically illustrating square and cross-shaped nanopore pattern structures processed on a chromium membrane according to example 3 of the present disclosure;
fig. 8 schematically shows a scanning electron micrograph of a nanograting structure fabricated on an Ag film according to example 4 of the disclosure;
figure 9 schematically shows a scanning electron microscope image of an open resonant ring SRR super surface device fabricated on an Au film in accordance with example 5 of the present disclosure;
fig. 10 schematically shows a scanning electron micrograph of Bowtie nanopores prepared on an Au film according to example 6 of the present disclosure.
Detailed Description
For the purpose of promoting a better understanding of the objects, aspects and advantages of the present disclosure, reference is made to the following detailed description taken in conjunction with the accompanying drawings.
The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the disclosure. The terms "comprises," "comprising," and the like, as used herein, specify the presence of stated features, steps, operations, and/or components, but do not preclude the presence or addition of one or more other features, steps, operations, or components.
The use of ordinal numbers such as "first," "second," "third," etc., in the specification and claims to modify a corresponding element does not by itself connote or represent any of the elements, nor do they represent the order in which an element is sequenced from another element or the order of fabrication, but are used merely to distinguish one element having a certain name from another element having a same name or name without departing from the scope of the invention.
In the ion beam etching process, the accelerated ion beam and the surface of the sample to be processed act, so that atoms on the surface of the sample to be processed are sputtered into the etching cavity, and the purity of etching gas in the etching cavity is reduced. The ion beam collides with other atoms in the etching cavity, so that the collimation of the ion beam and the energy of the ion beam reaching the surface of a sample to be processed are influenced, and the etching precision and the etching pattern quality of the ion beam are influenced; on the other hand, during the ion beam etching process, the ion beam interacts with the surface of the sample to be processed to generate heat, so that the temperature of the surface of the sample to be processed is increased, and the etching resistance of the photoresist and the contrast of the etched pattern of the substrate are affected.
In view of the above two problems, the present disclosure provides a method for processing a metal nanostructure by ion beam etching, referring to fig. 1, including: s1, placing a sample to be processed in ion beam etching equipment, wherein the sample to be processed sequentially comprises a substrate, a metal film layer and a photoresist nano pattern layer from bottom to top, and the photoresist nano pattern layer is exposed out of an etching area of the metal film layer; s2, etching the etching area of the metal film layer by using ion beams, wherein the etching time is a first time length t 1 (ii) a S3, intermittent ion beam etching is carried out, and the intermittent time is a second duration t 2 (ii) a S4, repeating S2-S3 until the etching depth reaches the target thickness; and S5, removing the photoresist nano pattern layer to obtain the target metal nano structure.
The intermittent etching method provided by the present disclosure, as shown in fig. 2, first uses an ion beam to etch the surface of a sample to be processed for a first time period t 1 Off for a second duration t 2 (ii) a Then etching the first time length t 1 Rest for a second duration t 2 N periods (t) 1 +t 2 ) Then the etching is finished, and the etching power is 200-300W. During the off-time, the degree of vacuum of the etching chamber is restored to a certain extent (as shown in fig. 4), so that the purity of the etching gas in the chamber in the next etching period is improved, and the temperature of the substrate is reduced during the off-time, thereby improving the etching precision of the sample pattern.
According to the method, an intermittent etching method is adopted, on one hand, the vacuum degree in the ion beam etching cavity is recovered in the intermittent time of each etching, the collimation of the ion beam is improved, and the energy loss when the ion beam reaches the surface of a sample to be processed is reduced. On the other hand, the temperature rise effect caused by ion beam etching can be reduced in the intermittent process, the photoresist deformation on the surface of the metal film layer is reduced, and the etching resistance is improved. By utilizing the effects of the two aspects, the etching precision and the quality of the etched pattern are finally improved, and the etching of the metal nano structure with the characteristic dimension of 100nm or even below 50nm can be realized.
On the basis of the above embodiment, S1 further includes preparing a sample to be processed, including: s11, cleaning the substrate; s12, depositing a layer of metal on the surface of the substrate to obtain a metal film layer; and S13, coating photoresist on the metal film layer, and exposing and developing to obtain the photoresist nano pattern layer.
Before etching the metal nanostructure, preparing a photoresist nano pattern layer, wherein the preparation of the photoresist nano pattern layer comprises the following steps: cleaning the substrate by using a conventional semiconductor cleaning method to remove pollutants on the surface of the substrate; depositing a metal film layer on the surface of the substrate, wherein the deposition method comprises magnetron sputtering deposition, electron beam evaporation deposition and the like; spin-coating photoresist on the metal film layer, wherein the thickness of the photoresist is 80-100 nm, after the photoresist is spin-coated, pre-baking the photoresist on a constant-temperature hot plate, and evaporating to remove an organic solvent in the photoresist; and exposing the photoresist layer obtained in the last step by a photoetching method, and developing to obtain the designed photoresist nano pattern layer. After the photoresist nano graph layer is prepared, the photoresist nano graph layer is placed in ion beam etching equipment for etching, and the structural schematic diagram of the intermittent etching method is shown in fig. 3.
On the basis of the above embodiment, S12 further includes: and depositing an adhesion promoting layer on the surface of the substrate to improve the adhesion between the substrate and the metal film layer.
If metals such as silver are directly deposited on the substrate, the adhesion may be poor, and then the adhesion between the substrate and the metal film layer can be improved by depositing an adhesion-promoting layer between the substrate and the metal film layer, so as to facilitate the subsequent ion beam etching process.
On the basis of the above embodiment, the substrate in S11 includes one of quartz, a silicon wafer, and sapphire; the metal in S12 comprises one of chromium, gold and silver; the photoresist in S13 includes a positive photoresist or a negative photoresist.
The material of the substrate comprises quartz, silicon wafers, sapphire and the like; the metal film layer is made of chromium, gold, silver and the like; the ion beam is an argon ion beam. The photoresist may be a positive photoresist such as PMMA (MicroChem Corp, USA), ZEP520A (Zeon Corp, japan), AR-P6200 (All Resist Gmbh, germany), or a negative photoresist such as HSQ (Micro Resist Technology Gmbh, germany), ma-N2400 series (Micro Resist Technology Gmbh, germany).
The shape of the substrate comprises a round shape, a square shape and the like; the diameter of the circular substrate is D, and the value range of D is more than 5mm and less than or equal to 220mm; the side length of the square substrate is L, and the value range of L is more than 5mm and less than or equal to 220mm.
On the basis of the above embodiment, the first time length t in S2 1 In the range of 5s ≤ t 1 Less than or equal to 250s; second duration t in S3 2 In the range of 5s to t 2 Less than or equal to 250s; and t is 2 ≥t 1 。
The value range of the thickness d of the metal film layer is that d is not less than 10nm and not more than 100nm; total etch time t = N (t) 1 +t 2 ) First duration t 1 Has a value range of t being not less than 5s 1 250s or less, preferably 5s or less t 1 150s or less, more preferably 10s or less t 1 Less than or equal to 20s; a second time period t 2 Has a value range of t less than or equal to 5s 2 250s or less, preferably 50s or less t 2 150s or less, more preferably 60s or less t 2 Less than or equal to 120s, wherein t 2 ≥t 1 ，t 2 ≥t 1 The vacuum degree in the etching chamber can be better recovered.
In addition to the above embodiment, the number of times of repeating S2 to S3 in S4 is more than 3.
The etching period is N, which has a value range N > 0, preferably N is greater than 3, which is determined by the thickness d of the metal film layer.
On the basis of the above embodiment, the removing the photoresist nanopattern layer in S5 includes: s51, removing the photoresist nano pattern layer by using oxygen plasma; and S52, cleaning the sample to be processed by a wet method to obtain the target metal nano structure.
And performing plasma etching on the photoresist layer by using oxygen plasma, removing the residual photoresist on the surface of the metal nano structure, and then cleaning by a wet method to obtain the target metal nano structure.
On the basis of the above embodiment, the target metal nanostructure obtained in S5 includes one of a metal nano circular hole, a metal nano square hole, a metal nano groove, a metal nano gap, and a metal nano lattice; the characteristic size range of the metal nano structure is 5 nm-100 nm.
The method disclosed by the invention can realize the preparation of the metal nano structure with the characteristic size of less than 100nm, and particularly can realize the processing of a gap with the minimum characteristic size of 22nm on a Cr film; the metal nanostructures that can be fabricated are not limited to the above 5, and other structures within the above-described feature size range can be realized by the design of the photoresist nanopattern layer.
The present disclosure also provides a metal nanostructure processed according to the aforementioned method of processing a metal nanostructure using ion beam etching.
The method disclosed by the invention is simple to operate, and can realize the processing of the metal nano structure with high resolution and high quality by only regulating and controlling the etching method without using toxic reaction gas to obtain the target metal nano structure.
The present disclosure also provides an application of the method for processing a metal nanostructure by using ion beam etching in ultraviolet lithography chrome mask processing, metal plasma nanostructure processing, metal nano antenna processing, and super surface processing.
The method for etching and processing the metal film nanostructure can be used for processing ultraviolet photo-etching chromium mask plates, metal plasma nanostructures, metal nano antennas, super surfaces and the like, and is wide in application.
The present disclosure is further illustrated by the following detailed description. The metal nanostructure and the ion beam etching method thereof are specifically described in the following embodiments. However, the following examples are only for illustrating the present disclosure, and the scope of the present disclosure is not limited thereto.
The method for processing the metal nano structure by using the ion beam etching comprises the following steps of:
s11, cleaning the substrate;
s12, depositing a metal film layer on the surface of the substrate;
and S13, coating photoresist on the metal film layer, and exposing and developing to obtain the photoresist nano pattern layer.
And S2-S4, placing a sample to be processed, which is provided with the photoresist nano pattern and the metal film layer with the thickness of d on the substrate, into an ion beam etching machine, and performing intermittent etching on the metal film layer for a plurality of periods by utilizing the ion beam. Each etching cycle includes: etching a sample to be processed by utilizing an ion beam for a first time period t 1 (ii) a Intermittent second time length t 2 To increase chamber vacuum and reduce sample temperature. The number N of the etching cycles is determined according to the thickness of the metal film layer.
And S5, removing the residual photoresist nano pattern layer to obtain the target metal nano structure.
From the above-described step S11 to step S5, 6 specific examples are provided below.
Example 1:
this example illustrates the preparation of a chromium film nanopattern, which includes the following steps:
step 11: preparing a circular transparent quartz substrate; the quartz substrate had a thickness of 3mm and a diameter of 25.4mm. Cleaning a quartz substrate by using a conventional semiconductor cleaning method to remove pollutants on the surface; corresponds to the above step S11.
Step 12: sputtering a chromium film (metal film layer) with the thickness of 40nm on the surface of a quartz substrate; corresponds to the above step S12.
Step 13: and spin-coating a layer of positive electron beam photoresist on the surface of the chromium layer by using a spin coater, wherein the thickness of the photoresist is 80-100 nm. After the photoresist is spin-coated, prebaking is carried out on a constant-temperature hot plate at 150 ℃, and organic solvent in the photoresist is removed by evaporation;
step 14: placing the quartz substrate coated with the positive electron beam photoresist in electron beam lithography equipment, directly writing and exposing nano patterns with different sizes and shapes on the photoresist by using an electron beam lithography technology, and then developing to obtain a photoresist nano pattern layer; corresponds to the above step S13.
Step 15: the quartz substrate with the photoresist nano pattern layer is placed into an ion beam etching machine, and the pattern is etched by the ion beam by adopting the intermittent etching method disclosed by the invention. Firstly, putting a sample into an etching cavity, and vacuumizing to a required value; then sequentially performing argon ion beamEtching for a first time period t 1 =10s, intermittent for a second time period t 2 =60s, 20 cycles total (i.e. N = 20); corresponds to the above steps S2 to S4.
Step 16: processing by oxygen plasma, and then removing residual photoresist on the surface of the chromium film after ion beam etching by using chemical liquid to obtain a required chromium film nano pattern; corresponds to the step S5.
And step 17: and characterizing the etched chromium film nano pattern by using a scanning electron microscope. Fig. 5a and 5b show patterns having different sizes and different shapes etched on the Cr film using the present embodiment. It can be seen that the mask pattern has clear edges and uniform pattern size distribution; the minimum feature size CD is 22nm.
Example 2:
this example illustrates the preparation of a Cr photolithographic mask grating pattern, which is performed as follows:
step 21: cleaning a quartz substrate with the diameter of 25.4mm and the thickness of 3mm, and depositing a layer of metal Cr film on the quartz substrate by adopting a magnetron sputtering method, wherein the thickness of the Cr film is 40nm; corresponds to the above steps S11 to S12.
Step 22: spin-coating 80nm electron beam photoresist on the quartz substrate plated with the Cr film, and performing prebaking, wherein the model of the spin-coated electron beam photoresist is AR-P6200; the pre-drying temperature is 150 ℃, and the pre-drying time is 10min;
step 23: the raster pattern is directly written by the electron beam exposure system. Developing the exposed pattern by using a developing solution after the exposure is finished to obtain a photoresist grating pattern layer; corresponds to the above step S13.
And step 24: and etching the developed grating pattern layer by using the ion beam etching equipment by adopting the intermittent etching method disclosed by the invention. When etching, the vacuum degree of the etching equipment cavity is pumped to 6 multiplied by 10 -7 Torr, starting radio frequency power, etching with argon ion beam, the radio frequency power during etching is 244W, and the pressure of the cavity during etching is 1.8 × 10 -4 Torr, etching with an argon ion beam for a first time period t 1 =15s, and is interrupted for a second time period t 2 Etching for 15 cycles (N = 20) =60 s; corresponds to the above steps S2 to S4.
Step 25: removing the electron beam photoresist by using oxygen plasma, and then cleaning by a wet method to obtain a Cr photoetching mask nano-grating structure; corresponds to the step S5.
FIGS. 6a and 6b are scanning electron micrographs of the Cr photomask raster pattern obtained by the process. The width of the grating gap is 22-25 nm, and the grating period is 130nm.
Example 3:
in this embodiment, the preparation of the square and cross-shaped nanopore Cr structure is exemplified, and the implementation steps are as follows:
step 31: cleaning a quartz substrate with the side length of 76.2mm and the thickness of 6.35mm, and plating a layer of chromium film on the quartz substrate by adopting a magnetron sputtering method, wherein the thickness of the chromium film is 40nm; corresponds to the above steps S11 to S12.
Step 32: the square-hole chromium film structure was prepared by the method of steps 22 to 25 in example 2. Etching with argon ion beam for a first time period t in performing the intermittent etching 1 =20s, intermittent for a second time period t 2 =120s, etching 10 cycles (N = 20); corresponding to steps S13 to S5 described above.
Fig. 7a and 7b are electron micrographs of square and cross-shaped nanopore patterned structures fabricated on a chromium membrane using the batch etching method of the present disclosure. The corners of the square hole pattern are relatively clear, and the minimum size of the square hole is 40nm. The minimum size of the cruciform nanopore is 20nm.
Example 4:
in this embodiment, the fabrication of nano-holes and nano-grating structures on an Ag film is exemplified, and the implementation steps are as follows:
step 41: cleaning a quartz substrate, plating a 3nm Cr film on a circular quartz substrate with the diameter of 25mm by using an electron beam evaporation method, and then plating a 50nm Ag film, wherein the Cr film is used as an adhesion layer to improve the adhesion between the Ag film and the quartz surface; corresponds to the above steps S11 to S12.
Step 42: spin-coating a layer of AZ3170 photoresist on a quartz substrate, wherein the thickness is 30nm; baking the photoresist for 60s by using a hot plate, wherein the temperature of the hot plate is 110 ℃;
step 43: exposing the photoresist by using an ultraviolet near-field photoetching method, and developing to obtain a designed photoresist nano graphic layer; corresponds to the above step S13.
Step 44: and etching the developed photoresist nano graph layer by using ion beam etching equipment by adopting the intermittent etching method disclosed by the invention. When etching, the vacuum degree of the etching equipment cavity is pumped to 6 multiplied by 10 -7 Torr, starting radio frequency power, etching with argon ion beam, the radio frequency power during etching is 244W, and the pressure of the cavity during etching is 1.8 × 10 -4 Torr, etching with an argon ion beam for a first time period t 1 =10s, intermittent for a second time period t 2 Etching for 6 cycles (N = 6) =80 s; corresponds to the above steps S2 to S4.
Step 45: removing the residual photoresist on the surface of the Ag film by using oxygen plasma, and then cleaning by a wet method to obtain Ag nano holes and a nano grating structure; corresponding to step S5 above.
Fig. 8 is a scanning electron micrograph of a nanograting grating prepared by the batch etching method of the present disclosure, and the width of the gap in the nanograting grating in fig. 8 is 70nm.
Example 5:
this example illustrates the processing of Au nanostructures, and the implementation steps are as follows:
step 51: cleaning a silicon substrate, plating a 5nm Cr film on the silicon substrate with the size of 2.5mm multiplied by 2.5mm by a magnetron sputtering method, and then plating a 50nm Au film, wherein the Cr film is used as an adhesion layer to improve the adhesion between the Ag film and the quartz surface; corresponds to the above steps S11 to S12.
Step 52: and spin-coating a layer of negative photoresist Ma-N2401 on the surface of the plated Au film, wherein the thickness of the photoresist is 100nm. Baking the wafer coated with the photoresist on a hot plate for 1 minute, wherein the temperature of the hot plate is 95 ℃;
step 53: exposing the designed SRR super-surface pattern by using electron beam lithography, and developing after exposure is finished to obtain a designed photoresist nano-pattern layer; corresponds to step S13 described above.
Step 54: and etching the developed photoresist nano graph layer by using ion beam etching equipment by adopting the intermittent etching method disclosed by the invention. During etchingPumping the vacuum degree of the etching equipment cavity to 6 multiplied by 10 -7 Torr, then starting radio frequency power, and etching with argon ion beam, wherein the radio frequency power during etching is 244W, and the pressure of the cavity during etching is 1.8 multiplied by 10 -4 Torr, etching with an argon ion beam for a first time period t 1 =15s, intermittent for a second time period t 2 Etching for 6 cycles (N = 6) =60 s; corresponds to the above steps S2 to S4.
Step 55: removing the residual photoresist on the surface of the Au nano structure by using oxygen plasma, and then cleaning by a wet method to obtain an Au SRR structure super-surface device; corresponds to the step S5.
FIG. 9 is a scanning electron micrograph of an open resonant ring SRR super surface device made using the batch etching method of the present disclosure. The width of the splitting gap of the SRR resonant ring is 36nm.
Example 6:
this example illustrates the processing of a Bowtie-shaped nanopore in a gold membrane, which is performed as follows:
step 61: cleaning a quartz substrate, plating a 5nm Cr film on the quartz substrate with the size of 2.5mm multiplied by 2.5mm by a magnetron sputtering method, and then plating a 50nm Au film; corresponds to the above steps S11 to S12.
Step 62: and spin-coating a layer of electron beam photoresist PMMA on the surface of the plated Au film, wherein the thickness of the photoresist is 150nm. Baking the wafer coated with the photoresist on a hot plate for 1 minute, wherein the temperature of the hot plate is 150 ℃;
and step 63: exposing the designed Bowtie graph by using electron beam lithography, and developing after exposure is finished to obtain a designed Bowtie photoresist nano graph layer; corresponds to the above step S13.
Step 64: and etching the developed photoresist nano graph layer by using ion beam etching equipment by adopting the intermittent etching method disclosed by the invention. When etching, the vacuum degree of the cavity of the etching equipment is pumped to 6 multiplied by 10 -7 Torr, then starting radio frequency power, and etching with argon ion beam, wherein the radio frequency power during etching is 244W, and the pressure of the cavity during etching is 1.8 multiplied by 10 -4 Torr, etching with an argon ion beam for a first time period t 1 =12s, intermittent for a second time period t 2 Etching for 6 pieces of etching solution for =80sPeriod (N = 6); corresponds to the above steps S2 to S4.
Step 65: removing the electron beam photoresist remained on the surface of the Au film by using oxygen plasma, and then cleaning by a wet method to obtain a gold film nanopore structure; corresponding to step S5 above.
FIG. 10 is a scanning electron micrograph of a gold film Bowtie nanopore prepared by the batch etching method of the present disclosure, and the gap size of the processed gold film Bowtie-shaped nanopore is 35nm.
According to the method, a metal film layer sample to be etched is placed in ion beam etching equipment, and is etched by using argon ion beams; and carrying out intermittent etching for a plurality of periods on the metal film layer. Each etching cycle includes: etching a sample to be processed for a first time period by using an argon ion beam; and intermittent for a second time period. In the second time of the intermittent etching, the purity of etching ions in the cavity of the etching equipment is recovered, the temperature of the sample is reduced, and the collimation and the energy retentivity of the etching ions and the etching resistance of the photoresist are improved.
The above-mentioned embodiments are intended to illustrate the objects, aspects and advantages of the present disclosure in further detail, and it should be understood that the above-mentioned embodiments are only illustrative of the present disclosure and are not intended to limit the present disclosure, and any modifications, equivalents, improvements and the like made within the spirit and principle of the present disclosure should be included in the scope of the present disclosure.
Claims (10)
1. A method of processing metallic nanostructures using ion beam etching, comprising:
s1, placing a sample to be processed in ion beam etching equipment, wherein the sample to be processed sequentially comprises a substrate, a metal film layer and a photoresist nano pattern layer from bottom to top, and the photoresist nano pattern layer is exposed out of an etching area of the metal film layer;
s2, etching the etching area of the metal film layer by using an ion beam, wherein the etching time is a first time length t 1 ；
S3, intermittently etching the ion beam, wherein the intermittent time is a second time length t 2 ；
S4, repeating the steps S2 to S3 until the etching depth reaches the target thickness;
and S5, removing the photoresist nano pattern layer to obtain the target metal nano structure.
2. The method for processing a metal nanostructure using ion beam etching as claimed in claim 1, wherein the S1 further comprises preparing the sample to be processed, comprising:
s11, cleaning the substrate;
s12, depositing a layer of metal on the surface of the substrate to obtain the metal film layer;
and S13, coating photoresist on the metal film layer, and exposing and developing to obtain the photoresist nano pattern layer.
3. The method for processing a metal nanostructure using ion beam etching as claimed in claim 2, wherein the S12 is preceded by:
and depositing an adhesion-promoting layer on the surface of the substrate to improve the adhesion between the substrate and the metal film layer.
4. The method of processing a metal nanostructure using ion beam lithography according to claim 2, wherein the substrate in S11 comprises one of quartz, silicon wafer, sapphire;
the metal in S12 comprises one of chromium, gold and silver;
the photoresist in S13 includes a positive photoresist or a negative photoresist.
5. The method of claim 1, wherein the first time period t in S2 is longer than the second time period t 1 In the range of 5s to t 1 Less than or equal to 250s; a second duration t in S3 2 In the range of 5s to t 2 Less than or equal to 250s; and t is 2 ≥t 1 。
6. The method of claim 1, wherein the number of times of repeating the S2 to S3 in the S4 is greater than 3.
7. The method of processing a metal nanostructure using ion beam etching as claimed in claim 1, wherein the removing of the photoresist nanopattern layer in S5 comprises:
s51, removing the photoresist nano pattern layer by using oxygen plasma;
and S52, cleaning the sample to be processed by a wet method to obtain the target metal nano structure.
8. The method of processing a metal nanostructure using ion beam lithography according to claim 1, wherein the target metal nanostructure obtained in S5 includes one of a metal nano circular hole, a metal nano square hole, a metal nano groove, a metal nano slit, and a metal nano lattice;
the characteristic size range of the metal nano structure is 5 nm-100 nm.
9. A metal nanostructure, characterized in that the metal nanostructure is processed according to any one of claims 1 to 8 by using the method of ion beam etching.
10. Use of the method of processing metallic nanostructures using ion beam lithography according to any of claims 1 to 8 in uv lithography chrome mask processing, metal plasma nanostructure processing, metal nanoantenna processing, super surface processing.
Priority Applications (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202211076513.1A CN115440585A (en) | 2022-09-01 | 2022-09-01 | Metal nanostructure and ion beam etching processing method thereof |
| PCT/CN2022/140699 WO2024045433A1 (en) | 2022-09-01 | 2022-12-21 | Metal nanostructure and ion beam etching processing therefor |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202211076513.1A CN115440585A (en) | 2022-09-01 | 2022-09-01 | Metal nanostructure and ion beam etching processing method thereof |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN115440585A true CN115440585A (en) | 2022-12-06 |
Family
ID=84246797
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202211076513.1A Pending CN115440585A (en) | 2022-09-01 | 2022-09-01 | Metal nanostructure and ion beam etching processing method thereof |
Country Status (2)
| Country | Link |
|---|---|
| CN (1) | CN115440585A (en) |
| WO (1) | WO2024045433A1 (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2024045433A1 (en) * | 2022-09-01 | 2024-03-07 | 中国科学院光电技术研究所 | Metal nanostructure and ion beam etching processing therefor |
Family Cites Families (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS62253785A (en) * | 1986-04-28 | 1987-11-05 | Tokyo Univ | Intermittent etching method |
| JP2005064408A (en) * | 2003-08-20 | 2005-03-10 | Nikon Corp | Reticle manufacturing method and exposure method |
| CN104142530B (en) * | 2013-05-06 | 2016-08-17 | 中国科学院物理研究所 | A kind of preparation method of the interdigital grating of metal nano |
| CN104326440A (en) * | 2014-10-31 | 2015-02-04 | 中国科学院光电技术研究所 | Manufacturing method of micro-nano structure capable of accurately controlling depth |
| CN111766222B (en) * | 2020-07-24 | 2022-03-15 | 江苏致微光电技术有限责任公司 | LSPR sensor based on flexible substrate and preparation method and application thereof |
| CN115440585A (en) * | 2022-09-01 | 2022-12-06 | 中国科学院光电技术研究所 | Metal nanostructure and ion beam etching processing method thereof |
-
2022
- 2022-09-01 CN CN202211076513.1A patent/CN115440585A/en active Pending
- 2022-12-21 WO PCT/CN2022/140699 patent/WO2024045433A1/en unknown
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2024045433A1 (en) * | 2022-09-01 | 2024-03-07 | 中国科学院光电技术研究所 | Metal nanostructure and ion beam etching processing therefor |
Also Published As
| Publication number | Publication date |
|---|---|
| WO2024045433A1 (en) | 2024-03-07 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US8894871B2 (en) | Lithography method using tilted evaporation | |
| JP3433721B2 (en) | Dry etching method and fine processing method | |
| US9684234B2 (en) | Sequential infiltration synthesis for enhancing multiple-patterning lithography | |
| CN103901516B (en) | The preparation method of grating | |
| US20130313223A1 (en) | Method for producing substrate having surface nanostructure | |
| JPH0258221A (en) | Etching method using carbon or mask mainly comprising carbon | |
| CN106809802A (en) | The preparation method of large-area metal nanometer pinpoint array in a kind of flexible substrate | |
| CN111071985B (en) | Method for firmly fixing metal nano particles by introducing anode aluminum oxide film of sacrificial layer | |
| CN104459854A (en) | Preparation method of metal grating | |
| CN101566799B (en) | Method for preparing hollowed-out polyimide evaporation shadow mask | |
| CN115440585A (en) | Metal nanostructure and ion beam etching processing method thereof | |
| CN109712879A (en) | A kind of metal mask forming method for wafer dry etch process | |
| JP2010503993A (en) | Improved etching techniques for lift-off patterning | |
| JP2010216012A (en) | Mask for vapor deposition | |
| JP4971305B2 (en) | Method for forming small getter deposition layer | |
| US20080085479A1 (en) | Pattern forming method and device production process using the method | |
| JP2010274650A (en) | Manufacturing of metal stamp for duplicating technique | |
| CN108569850A (en) | A kind of multiple layer metal mask seed layer and its manufacturing method for glass HF corrosion | |
| JP2012023242A (en) | Pattern manufacturing method and pattern formed body formed thereby | |
| JP2011167780A (en) | Pattern forming method and pattern formation object | |
| WO2005015308A2 (en) | Fabrication process for high resolution lithography masks using evaporated or plasma assisted electron sensitive resists with plating image reversal | |
| CN106154744A (en) | A kind of preparation method of metal nanometer line | |
| CN110928142A (en) | Method for improving binding force of photoresist and metal substrate | |
| CN109437093A (en) | Self-supporting micro nano structure and preparation method thereof | |
| KR100272517B1 (en) | Mask structuring method of semiconductor device |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination |