CN113421826A - Atomic-level precision lossless layer-by-layer etching method for two-dimensional layered material - Google Patents
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Abstract
The invention provides an atomic-scale precision lossless layer-by-layer etching method for a two-dimensional layered material, which comprises the following steps of: manufacturing lattice defects on the surface layer of a material to be etched by utilizing a surface treatment technology; depositing a thermal diffusion sacrificial material on the surface layer of the material to be etched; thermally annealing the material to be etched at a certain temperature to enable the diffusion sacrificial material to diffuse into the surface layer of the material to be etched to form an alloy layer; removing the diffusion sacrificial material and the alloy layer thereof by utilizing selective chemical reaction to complete local etching; the two-dimensional layered material to be etched comprises one or a combination of metal sulfide, metal selenide, metal telluride, graphene and black phosphorus; the diffusion sacrificial material comprises one or a combination of low-atomic-radius metal, low-atomic-radius non-metallic material and small-molecule organic matter. The sacrificial layer is not diffused into the internal retention layer of the material to be etched, so that the etching process does not damage the crystal lattice of the material retention layer, the intrinsic electrical property of the material is maintained, and the method is a lossless etching technology.
Description
Technical Field
The invention relates to the field of semiconductor material processing, in particular to an atomic-level precision lossless layer-by-layer etching method for a two-dimensional layered material.
Background
As semiconductor microelectronic transistor dimensions continue to shrink, moore's law is gradually moving towards the physical limits of material processing. The decline of the channel mobility caused by the factors such as the etching precision and the thickness fluctuation is a main bottleneck for limiting the further reduction of the silicon-based device. The way to break through the bottleneck is to develop a semiconductor channel with atomic-level thickness and flatness and a matched etching processing technology thereof. The two-dimensional material with the layered atomic structure meets the structural requirements of the materials, is a powerful candidate for the next-generation semiconductor channel material, and receives extensive attention and research. However, the CMOS compatible complete ultrahigh atomic precision nondestructive etching technology is still lacked at present, and the etching technology can realize atomic-level etching precision and can ensure that the etched material keeps intrinsic electrical characteristics.
The material with three-dimensional atomic structure (such as silicon) is limited by atomic chemical bonds, and the etched surface is filled with unsaturated chemical bonds, so that a nondestructive etching scheme does not exist. The two-dimensional layered material has a unique layered atomic structure, so that after the surface layer is etched, the chemical bond on the new surface is self-saturated, and theoretically, lossless etching can be obtained. At present, some schemes are reported to perform atomic-level high-precision processing on two-dimensional materials, but most of the schemes cannot achieve the aim of nondestructive etching.
Such as Castellanos-Gomez, A.et al, Laser-thining of MoS2On Demand Generation of a Single-Layer Semiconductor, Nano Lett.,12,3187(2012) (Castellanos-Gomez et al, MoS2Laser thinning: customized single-layer semiconductors, nanometer Kuntze letters, volume 2012, p 3187) discloses a MoS with nanometer thickness ablated by laser2Nanosheets to obtain a single layer of MoS2The method of (1). The disadvantage of this approach is that the etch accuracy is low, down to the atomic level, and the lattice integrity of the target sample is compromised.
Such as Wu, J.et al, Layer thinking and ething of mechanical extended MoS2Nanosheets by Thermal Annealing in Air, Small,9,3314(2013) (Wu J et al, MoS mechanical exfoliation by Thermal Annealing in Air2The layered thinning and etching of the nanosheets, volume 9 of 2013, page 3314) discloses that the layer-by-layer etching precision is realized by precisely controlling the oxidation temperature and atmosphere by using a thermal oxidation etching method, but the scheme still damages the electrical properties of the target material.
Such as Lin, T.et al, Controlled Layer-by-Layer Etching of MoS2ACS appl. Mater. interfaces,7,15892(2015) (Lin T et al, controlled etch MoS layer by layer2Book of infection of the United statesSociety-applied materials & interfaces-volume 7, 2015 15892) disclosed a method for layer-by-layer etching using argon plasma bombardment of MoS2 surfaces. The scheme still can indiscriminately etch the etching and retaining layers of the sample because the surface of the material is not treated, and the electrical performance of the material is damaged.
All reported two-dimensional material etching technologies facing CMOS applications have a significant disadvantage, namely, poor etching selectivity; during the etching process, the high-energy etching medium acts on the layer to be etched and the remaining layer of the material at the same time, thereby causing lattice damage and significant degradation of electrical properties of the remaining layer.
Therefore, how to design an atomic-level precision lossless layer-by-layer etching method for a two-dimensional layered material can obtain single-atomic-level high-precision etching, and maintain the electrical performance of the material without damaging a reserved layer at the lower part of the material is a very important matter to be solved.
Disclosure of Invention
In view of the above, the present invention provides an atomic-level precision lossless layer-by-layer etching method for a two-dimensional layered material, which has an ultra-high etching selection ratio, can satisfy the ultra-high etching precision at the atomic level, and does not damage a lower retention layer of the material, so as to solve the problems in the background art.
In order to achieve the above object, the present application provides the following technical solutions.
An atomic-level precision lossless layer-by-layer etching method for a two-dimensional layered material comprises the following steps:
step 1: manufacturing lattice defects on the surface of a layer to be etched of a two-dimensional layered material to be etched by using a surface treatment technology;
step 2: depositing a thermal diffusion sacrificial material on the treated layer to be etched;
and step 3: thermally annealing the sample to be etched, which is attached with the diffusion sacrificial material, at a certain temperature to enable the diffusion sacrificial material to diffuse into the layer to be etched, so as to form an alloy layer;
and 4, step 4: and removing the non-diffused diffusion sacrificial material and the alloy layer thereof by utilizing selective chemical reaction to complete the local etching of the layer to be etched.
Preferably, before step 1, a PMMA electron beam glue is spin-coated on the two-dimensional layered material to be etched, and the area to be etched is defined by electron beam exposure.
Preferably, in step 1, the surface treatment technique includes one or a combination of plasma bombardment, high temperature thermal annealing, chemical molecular deposition, and chemical solvent immersion.
Preferably, in step 1, the two-dimensional layered material to be etched includes one or a combination of metal sulfide, metal selenide, metal telluride, graphene and black phosphorus.
Preferably, in step 2, the diffusion sacrificial material comprises one or a combination of a low atomic radius metal, a low atomic radius non-metallic material and a small molecule organic matter.
Preferably, after step 2, the PMMA glue and the overlying diffusion sacrificial material are removed, leaving only the diffusion sacrificial material on the areas to be etched.
Preferably, in step 3, the thermal annealing temperature is 80-500 ℃.
Preferably, in step 4, the selective chemical reaction includes one or a combination of acid cleaning, alkali cleaning and gas phase reaction.
Preferably, after completing one layer of etching in steps 1-4, repeating steps 1-4 to realize deep etching of the material layer by layer.
Compared with the prior art, the technical scheme of the invention has the following beneficial effects:
1. the invention utilizes the different thermal diffusion capability of the atoms of the sacrificial layer material between the two-dimensional layered material with rich defects and no defects to obtain the selective thermal diffusion of the sacrificial layer material to the surface layer and the interior of the layered material, thereby realizing the precise control of the diffusion depth and the atomic level of the subsequent etching.
2. The sacrificial layer in the invention does not diffuse into the material retaining layer to be etched, and has an ultra-high etching selection ratio during etching, so that the material retaining layer is not damaged by an etching medium on the premise of effectively removing the etching layer, the intrinsic physical property and the electrical property of the material retaining layer are maintained, and the method is a non-destructive etching technology.
3. The ultrahigh-precision etching step of the monoatomic layer can be repeated, the layer-by-layer etching of the layered material can be realized, and the controllability of the etching depth is realized.
4. All the process flows in the invention are compatible with the existing CMOS process, and are suitable for industrial application.
Drawings
In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings needed to be used in the description of the embodiments or the prior art will be briefly introduced below, and it is obvious that the drawings in the following description are some embodiments of the present application, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without creative efforts. Throughout the drawings, like elements or portions are generally identified by like reference numerals. In the drawings, elements or portions are not necessarily drawn to scale.
FIG. 1 is a flow chart of an atomic-scale precision lossless layer-by-layer etching method for a two-dimensional layered material according to the present invention;
FIG. 2 is a schematic diagram of a lattice defect produced on a surface layer of a two-dimensional layered material to be etched by using a surface treatment technique in an atomic-scale precision lossless layer-by-layer etching method for the two-dimensional layered material according to the present invention;
FIG. 3 is a schematic diagram of depositing a thermal diffusion sacrificial material on a layer to be etched in an atomic-scale precision lossless layer-by-layer etching method for a two-dimensional layered material according to the present invention;
FIG. 4 is a schematic diagram of a process of forming an alloy layer by diffusing a sacrificial material into a layer to be etched during thermal annealing of the material to be etched attached with the sacrificial layer in the atomic-scale precision lossless layer-by-layer etching method for a two-dimensional layered material according to the present invention;
FIG. 5 is a schematic diagram of local etching of a two-dimensional layered surface layer after a sacrificial material and an alloy layer thereof are removed by selective chemical reaction in the atomic-scale precision lossless layer-by-layer etching method for a two-dimensional layered material according to the present invention;
FIG. 6 is a local atomic force microscope photograph including sample etching and an original region in the atomic-scale precision lossless layer-by-layer etching method for a two-dimensional layered material provided by the present invention;
FIG. 7 shows single-layer and double-layer MoS prepared in the atomic-scale precision lossless layer-by-layer etching method for two-dimensional layered materials provided by the invention2Comparing the value of the electrical mobility of the sample with that of the sample with the same thickness obtained by other destructive etching methods;
FIG. 8 shows MoS after two times of etching along vertical and horizontal directions in the atomic-scale precision lossless layer-by-layer etching method for two-dimensional layered materials provided by the invention2A surface-defined checkerboard pattern;
FIG. 9 shows MoS in the atomic-scale precision lossless layer-by-layer etching method for a two-dimensional layered material provided by the invention2The raman spectra of the areas where the surface was not etched, etched once and etched twice.
In the figure: 11. etching the two-dimensional layered material; 12. etching the layer to be etched; 13. a retention layer; 14. diffusing the sacrificial material; 15. a material to be etched to which a diffusion sacrificial material is attached; 16. an alloy layer; 21. an unetched original region; 22. etching the once region; 23. regions are alternately etched twice.
Detailed Description
In order to make the objects, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are some embodiments of the present application, but not all embodiments. In the following description, specific details such as specific configurations and components are provided only to help the embodiments of the present application be fully understood. Accordingly, it will be apparent to those skilled in the art that various changes and modifications may be made to the embodiments described herein without departing from the scope and spirit of the present application. In addition, descriptions of well-known functions and constructions are omitted in the embodiments for clarity and conciseness.
It should be appreciated that reference throughout this specification to "one embodiment" or "the embodiment" means that a particular feature, structure or characteristic described in connection with the embodiment is included in at least one embodiment of the present application. Thus, the appearances of the phrase "one embodiment" or "the present embodiment" in various places throughout this specification are not necessarily all referring to the same embodiment. Furthermore, the particular features, structures, or characteristics may be combined in any suitable manner in one or more embodiments.
Further, the present application may repeat reference numerals and/or letters in the various examples. This 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.
The term "and/or" herein is merely an association describing an associated object, meaning that three relationships may exist, e.g., a and/or B, may mean: a exists alone, B exists alone, and A and B exist at the same time, and the term "/and" is used herein to describe another association object relationship, which means that two relationships may exist, for example, A/and B, may mean: a alone, and both a and B alone, and further, the character "/" in this document generally means that the former and latter associated objects are in an "or" relationship.
The term "at least one" herein is merely an association relationship describing an associated object, and means that there may be three relationships, for example, at least one of a and B, may mean: a exists alone, A and B exist simultaneously, and B exists alone.
It is further noted that, herein, relational terms such as first and second, and the like may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion.
Example 1
The embodiment introduces an atomic-scale precision lossless layer-by-layer etching method for a two-dimensional layered material.
The difficulty of the invention is that the following two points are simultaneously realized in the material etching processing:
1) obtaining high-precision etching of single atom level;
2) the ultra-high etching selection ratio is obtained, so that the etching medium does not damage the material retaining layer and keeps the intrinsic physical properties of the material retaining layer on the premise of effectively removing the etching layer.
Referring to fig. 1, fig. 1 is a flowchart of an atomic-scale precision lossless layer-by-layer etching method for a two-dimensional layered material according to the present invention, which shows an atomic-scale precision lossless layer-by-layer etching method for a two-dimensional layered material, including the following steps:
referring to fig. 2, fig. 2 is a schematic diagram of manufacturing lattice defects on a surface layer of a two-dimensional layered material 11 to be etched by using a surface treatment technique in an atomic-scale precision lossless layer-by-layer etching method for a two-dimensional layered material according to the present invention, which shows step 1: lattice defects are created in the layer to be etched 12 of the two-dimensional layered material 11 to be etched by means of a surface treatment technique.
Referring to fig. 3, fig. 3 is a schematic diagram of depositing a thermal diffusion sacrificial material 14 on a layer to be etched 12 in an atomic-scale precision lossless layer-by-layer etching method for a two-dimensional layered material according to the present invention, which shows step 2: a thermally diffusing sacrificial material 14 is deposited over the layer to be etched 12.
Referring to fig. 4, fig. 4 is a schematic diagram of a process of forming an alloy layer 16 by diffusing a sacrificial material into a layer to be etched 12 during thermal annealing of a material to be etched attached with the sacrificial layer in the atomic-scale precision lossless layer-by-layer etching method for a two-dimensional layered material according to the present invention, which shows step 3: the material to be etched 15 with the attached diffusion sacrificial material is thermally annealed at a certain temperature to diffuse the diffusion sacrificial material 14 into the layer to be etched 12 to form an alloy layer 16.
Referring to fig. 5, fig. 5 is a schematic diagram of a two-dimensional layered surface layer to be etched after removing a sacrificial material and an alloy layer 16 thereof by using a selective chemical reaction in the atomic-scale precision lossless layer-by-layer etching method for a two-dimensional layered material according to the present invention, which shows step 4: as shown in fig. 4, the diffusion sacrificial material 14 and its alloy layer 16 are removed by selective chemical reaction to complete the partial etching of the layer to be etched 12.
Further, the two-dimensional layered material to be etched 11 includes a layer to be etched 12 and a remaining layer 13.
Further, before step 1, a PMMA electron beam glue is spin-coated on the two-dimensional layered material 11 to be etched, and an area to be etched is defined by electron beam exposure.
Further, after step 2, the PMMA glue and the overlying diffusion sacrificial material 14 are removed, leaving only the diffusion sacrificial material 14 on the areas to be etched.
Further, in step 1, the surface treatment technique includes one or a combination of plasma bombardment, high-temperature thermal annealing, chemical molecular deposition, and chemical solvent immersion.
Further, in step 1, the two-dimensional layered material 11 to be etched includes one or a combination of a metal sulfide, a metal selenide, a metal telluride, graphene and black phosphorus.
Further, in step 2, the diffusion sacrificial material 14 includes one or a combination of a low atomic radius metal, a low atomic radius non-metallic material, and a small molecule organic substance.
Further, in the step 3, the thermal annealing temperature is 80-500 ℃.
Further, in step 4, the selective chemical reaction includes, but is not limited to, one or a combination of acid cleaning, alkali cleaning, and gas phase reaction.
Further, after the step 1-4 is completed, the step 1-4 is repeated to realize the layer-by-layer etching of the material.
The invention utilizes the different thermal diffusion capability of the atoms of the sacrificial layer material between the two-dimensional layered material with rich defects and no defects to obtain the selective thermal diffusion of the sacrificial layer material to the surface layer and the interior of the layered material, thereby realizing the precise control of the diffusion depth and the atomic level of the subsequent etching.
The sacrificial layer in the invention does not diffuse into the material retaining layer to be etched, and has an ultra-high etching selection ratio during etching, so that the material retaining layer is not damaged by an etching medium on the premise of effectively removing the etching layer, the intrinsic physical property and the electrical property of the material retaining layer are maintained, and the method is a non-destructive etching technology.
Example 2
Based on the foregoing embodiment 1, this embodiment describes in detail an atomic-scale precision lossless layer-by-layer etching method for a two-dimensional layered material.
Step 1: MoS to be etched by using mechanical stripping method2The nanosheets were transferred to a silicon wafer.
Step 2: and (3) spin-coating PMMA electron beam glue, and defining an area to be etched through electron beam exposure.
And step 3: the patterned MoS to be etched2The nanosheets are subjected to Reactive Ion Etching (RIE), and bombarded with plasma at low power (30W) for 30s, so that lattice defects are introduced on the surface of the area to be etched.
And 4, step 4: in the MoS to be etched2And evaporating 10nm metal aluminum on the nano-sheet as a thermal diffusion sacrificial layer.
And 5: and removing the PMMA glue and the upper layer of aluminum by using a solvent stripping method, and only leaving the aluminum sacrificial layer on the area to be etched.
Step 6: MoS to be etched with sacrificial layer2The nano-sheet is placed in an annealing furnace at 250 ℃ for half an hour to promote the diffusion of the metal aluminum sacrificial layer into the MoS2The defective surface layer of (2).
And 7: soaking the sample in hydrochloric acid for half an hour to dissolve the aluminum sacrificial layer and the MoS alloyed by aluminum after diffusion2Defective surface layer, realizing single-layer MoS2And (3) once patterning high-precision etching.
Referring to fig. 6, fig. 6 is a local afm image of an original area and a sample etching included in the atomic-scale precision lossless layer-by-layer etching method for a two-dimensional layered material according to the present invention, which shows that the height of the etched area is reduced by 0.67 nm.
Referring to fig. 7, fig. 7 shows a single-layer and a double-layer MoS fabricated in the atomic-level precision lossless layer-by-layer etching method for two-dimensional layered materials according to the present invention2The comparison of the electrical mobility values of samples with the same thickness obtained by other lossy etching methods shows that the samples prepared by the etching scheme of the invention have higher mobility compared with the samples prepared by the etching schemes of thermal oxidation, laser, plasma, hand tearing and the like. Sample quality and intrinsic mechanical exfoliation of the present inventionThe same as the sample, the crystal lattice of the etched material is hardly damaged, and the intrinsic electrical property of the material is maintained.
Example 3
Based on the foregoing embodiment 2, this embodiment mainly introduces an atomic-scale precision lossless layer-by-layer etching method for a two-dimensional layered material.
Step 1: MoS to be etched by using mechanical stripping method2The nanosheets were transferred to a silicon wafer.
Step 2: the single layer was etched in the vertical direction by repeating steps 2 to 7 of example 2 to form a strip-like thinned region having a vertical periodic structure.
And step 3: the steps 2-7 of example 2 were repeated to etch the single layer in the horizontal direction to form the strip-like thinned region with a horizontal periodic structure.
Referring to fig. 8, fig. 8 shows a MoS after two times of etching along the vertical and horizontal directions in the atomic-level precision lossless layer-by-layer etching method for two-dimensional layered materials according to the present invention2A chessboard pattern defined on the surface showing the MoS formed after two etchings along the vertical crossing direction by the above step 2 and step 32The nano-sheet has chessboard pattern characteristics locally. In the figure 21 is an unetched original area 21, 22 is an area 22 etched once, and 23 is an area 23 alternately etched twice.
Referring to fig. 9, fig. 9 shows MoS in the atomic-level precision lossless layer-by-layer etching method for two-dimensional layered material according to the present invention2Raman spectra of the areas with un-etched, etched once and etched twice of the surface, showing raman thickness measurements of the above areas, 21 from the un-etched original area 21, 22 from the area with etched once 22, 23 from the area with alternating etched twice 23. The raman characteristic peak spacings indicated that the regions 21, 22, 23 had thicknesses of 3 layers, 2 layers and 1 layer, respectively.
The ultrahigh-precision etching step of the monoatomic layer can be repeated, and the layered material can be deeply etched layer by layer.
Example 4
Based on the foregoing embodiment 1, this embodiment mainly introduces another atomic-scale precision lossless layer-by-layer etching method for a two-dimensional layered material.
The two-dimensional layered material to be etched is MoSe2。
Step 1: MoSe to be etched by using mechanical stripping method2The nanosheets were transferred to a silicon wafer.
Step 2: to-be-etched MoSe2And (3) annealing the nanosheets in the air at 300 ℃ for 10 minutes to introduce lattice defects on the nanosheets.
And step 3: in the presence of MoSe to be etched2And evaporating 10nm metal aluminum on the nano-sheet as a thermal diffusion sacrificial layer.
And 4, step 4: MoSe to be etched with sacrificial layer2The nano-sheet is placed in an annealing furnace at 250 ℃ for half an hour to promote the diffusion of the metal aluminum sacrificial layer into the MoSe2The defective surface layer of (2).
And 5: place the sample in Cl2Plasma dry etching to remove sacrificial layer and alloyed MoSe after diffusion of aluminum2Defect surface layer to realize single-layer MoSe2One global etch of (1).
All the process flows in the invention are compatible with the existing CMOS process, and are suitable for industrial application.
The above description is only a preferred embodiment of the present invention, and it is not intended to limit the scope of the present invention, and various modifications and changes may be made by those skilled in the art. Variations, modifications, substitutions, integrations and parameter changes of the embodiments may be made without departing from the principle and spirit of the invention, which may be within the spirit and principle of the invention, by conventional substitution or may realize the same function.
Claims (9)
1. An atomic-level precision lossless layer-by-layer etching method for a two-dimensional layered material is characterized by comprising the following steps of:
step 1: manufacturing lattice defects on the surface of a layer (12) to be etched of a two-dimensional layered material (11) to be etched by using a surface treatment technology;
step 2: depositing a thermal diffusion sacrificial material (14) on the treated layer (12) to be etched;
and step 3: thermally annealing a sample of the material to be etched (15) with the diffusion sacrificial material attached thereto at a certain temperature to diffuse the diffusion sacrificial material (14) into the layer to be etched (12) to form an alloy layer (16);
and 4, step 4: the non-diffused diffusion sacrificial material (14) and its alloy layer (16) are removed by selective chemical reaction to complete the partial etching of the layer to be etched (12).
2. The atomic-scale precision lossless layer-by-layer etching method for the two-dimensional layered material as claimed in claim 1, wherein before step 1, PMMA electron beam glue is spin-coated on the two-dimensional layered material (11) to be etched, and the area to be etched is defined by electron beam exposure.
3. A method for atomic-scale precision non-destructive, layer-by-layer etching of a two-dimensional layered material, as claimed in claim 2, wherein after step 2, the PMMA glue and the overlying diffusion sacrificial material (14) are removed, leaving only the diffusion sacrificial material (14) on the areas to be etched.
4. The atomic-scale precision lossless layer-by-layer etching method for the two-dimensional layered material as claimed in any one of claims 1 to 3, wherein in step 1, the surface treatment technique comprises one or a combination of plasma bombardment, high temperature thermal annealing, chemical molecular deposition and chemical solvent immersion.
5. The atomic-scale precision lossless layer-by-layer etching method for the two-dimensional layered material as claimed in claim 4, wherein in step 1, the two-dimensional layered material (11) to be etched comprises one or a combination of metal sulfide, metal selenide, metal telluride, graphene and black phosphorus.
6. The atomic-scale precision lossless layer-by-layer etching method for the two-dimensional layered material according to any one of claims 1 to 3 or 5, characterized in that, in the step 2, the diffusion sacrificial material (14) comprises one or a combination of low atomic radius metal, low atomic radius non-metallic material and small molecular organic matter.
7. The atomic-scale precision lossless layer-by-layer etching method for the two-dimensional layered material according to any one of claims 1 to 3 or 5, wherein in the step 3, the thermal annealing temperature is 80 to 500 ℃.
8. The atomic-scale precision lossless layer-by-layer etching method for the two-dimensional layered material according to any one of claims 1 to 3 or 5, wherein in the step 4, the selective chemical reaction comprises one or a combination of acid cleaning, alkali cleaning and gas phase reaction.
9. The atomic-scale precision lossless layer-by-layer etching method for the two-dimensional layered material as claimed in any one of claims 1 to 4, wherein after the completion of one layer etching in steps 1 to 4, the steps 1 to 4 are repeated to complete the deep layer-by-layer etching of the material.
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN117012812A (en) * | 2023-10-07 | 2023-11-07 | 之江实验室 | Method for etching two-dimensional tellurium alkene by combining wet method and dry method |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5350709A (en) * | 1992-06-13 | 1994-09-27 | Sanyo Electric Co., Ltd. | Method of doping a group III-V compound semiconductor |
| US5994208A (en) * | 1995-06-23 | 1999-11-30 | Prins; Johan Frans | Doping in crystalline diamond substrates |
| US7018877B1 (en) * | 2004-09-28 | 2006-03-28 | Palo Alto Research Center | Selective delamination of thin-films by interface adhesion energy contrasts and thin film transistor devices formed thereby |
| CN101774540A (en) * | 2010-02-09 | 2010-07-14 | 浙江大学 | Quantum well mixing method |
| CN103515197A (en) * | 2012-06-26 | 2014-01-15 | 中芯国际集成电路制造(上海)有限公司 | Self-aligned multi-patterning mask layer and formation method thereof |
| CN106276873A (en) * | 2016-08-08 | 2017-01-04 | 中国科学院上海微系统与信息技术研究所 | A kind of method preparing germanio grapheme nano-pore |
-
2021
- 2021-06-18 CN CN202110675975.4A patent/CN113421826B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5350709A (en) * | 1992-06-13 | 1994-09-27 | Sanyo Electric Co., Ltd. | Method of doping a group III-V compound semiconductor |
| US5994208A (en) * | 1995-06-23 | 1999-11-30 | Prins; Johan Frans | Doping in crystalline diamond substrates |
| US7018877B1 (en) * | 2004-09-28 | 2006-03-28 | Palo Alto Research Center | Selective delamination of thin-films by interface adhesion energy contrasts and thin film transistor devices formed thereby |
| CN101774540A (en) * | 2010-02-09 | 2010-07-14 | 浙江大学 | Quantum well mixing method |
| CN103515197A (en) * | 2012-06-26 | 2014-01-15 | 中芯国际集成电路制造(上海)有限公司 | Self-aligned multi-patterning mask layer and formation method thereof |
| CN106276873A (en) * | 2016-08-08 | 2017-01-04 | 中国科学院上海微系统与信息技术研究所 | A kind of method preparing germanio grapheme nano-pore |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN117012812A (en) * | 2023-10-07 | 2023-11-07 | 之江实验室 | Method for etching two-dimensional tellurium alkene by combining wet method and dry method |
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