CN113223936A - Preparation method of InP-based nano periodic structure - Google Patents
Preparation method of InP-based nano periodic structure Download PDFInfo
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- CN113223936A CN113223936A CN202110342868.XA CN202110342868A CN113223936A CN 113223936 A CN113223936 A CN 113223936A CN 202110342868 A CN202110342868 A CN 202110342868A CN 113223936 A CN113223936 A CN 113223936A
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- inp
- electron beam
- periodic structure
- glue
- exposure
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- 230000000737 periodic effect Effects 0.000 title claims abstract description 18
- 238000002360 preparation method Methods 0.000 title claims abstract description 9
- 238000010894 electron beam technology Methods 0.000 claims abstract description 33
- 238000000034 method Methods 0.000 claims abstract description 26
- 239000003292 glue Substances 0.000 claims abstract description 24
- VNWKTOKETHGBQD-UHFFFAOYSA-N methane Chemical compound C VNWKTOKETHGBQD-UHFFFAOYSA-N 0.000 claims abstract description 18
- 239000000758 substrate Substances 0.000 claims abstract description 18
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 claims abstract description 9
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 claims abstract description 9
- 239000001257 hydrogen Substances 0.000 claims abstract description 9
- 229910052739 hydrogen Inorganic materials 0.000 claims abstract description 9
- 229910052710 silicon Inorganic materials 0.000 claims abstract description 9
- 239000010703 silicon Substances 0.000 claims abstract description 9
- 238000004140 cleaning Methods 0.000 claims abstract description 7
- 238000005530 etching Methods 0.000 claims abstract description 6
- 239000011248 coating agent Substances 0.000 claims abstract description 5
- 238000000576 coating method Methods 0.000 claims abstract description 5
- 238000005516 engineering process Methods 0.000 claims abstract description 5
- KFZMGEQAYNKOFK-UHFFFAOYSA-N Isopropanol Chemical compound CC(C)O KFZMGEQAYNKOFK-UHFFFAOYSA-N 0.000 claims description 8
- URLKBWYHVLBVBO-UHFFFAOYSA-N Para-Xylene Chemical group CC1=CC=C(C)C=C1 URLKBWYHVLBVBO-UHFFFAOYSA-N 0.000 claims description 8
- FXHOOIRPVKKKFG-UHFFFAOYSA-N N,N-Dimethylacetamide Chemical compound CN(C)C(C)=O FXHOOIRPVKKKFG-UHFFFAOYSA-N 0.000 claims description 4
- 230000001133 acceleration Effects 0.000 claims description 4
- 238000005229 chemical vapour deposition Methods 0.000 claims description 4
- 239000003085 diluting agent Substances 0.000 claims description 4
- 238000009616 inductively coupled plasma Methods 0.000 claims description 4
- 238000002791 soaking Methods 0.000 claims description 3
- 239000007789 gas Substances 0.000 claims description 2
- 238000004528 spin coating Methods 0.000 claims 2
- 238000000151 deposition Methods 0.000 abstract description 4
- 230000000694 effects Effects 0.000 abstract description 4
- 238000001020 plasma etching Methods 0.000 abstract description 4
- 238000009825 accumulation Methods 0.000 abstract description 3
- 238000006243 chemical reaction Methods 0.000 abstract description 3
- 230000008021 deposition Effects 0.000 abstract description 3
- 239000002086 nanomaterial Substances 0.000 abstract description 3
- 230000001808 coupling effect Effects 0.000 abstract description 2
- 230000002195 synergetic effect Effects 0.000 abstract description 2
- 230000008878 coupling Effects 0.000 abstract 1
- 238000010168 coupling process Methods 0.000 abstract 1
- 238000005859 coupling reaction Methods 0.000 abstract 1
- 230000001939 inductive effect Effects 0.000 abstract 1
- 238000000609 electron-beam lithography Methods 0.000 description 3
- 239000004065 semiconductor Substances 0.000 description 3
- 229920000642 polymer Polymers 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000003749 cleanliness Effects 0.000 description 1
- 238000001035 drying Methods 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 229920013730 reactive polymer Polymers 0.000 description 1
- 239000013049 sediment Substances 0.000 description 1
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
- H01L21/027—Making masks on semiconductor bodies for further photolithographic processing not provided for in group H01L21/18 or H01L21/34
- H01L21/0271—Making masks on semiconductor bodies for further photolithographic processing not provided for in group H01L21/18 or H01L21/34 comprising organic layers
- H01L21/0273—Making masks on semiconductor bodies for further photolithographic processing not provided for in group H01L21/18 or H01L21/34 comprising organic layers characterised by the treatment of photoresist layers
- H01L21/0277—Electrolithographic processes
-
- 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 potential barriers, e.g. a PN junction, depletion layer or carrier concentration layer
- H01L21/18—Manufacture or treatment of semiconductor devices or of parts thereof the devices having potential barriers, e.g. a PN junction, depletion layer or carrier concentration layer the devices having semiconductor bodies comprising elements of Group IV of the Periodic Table 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
Landscapes
- Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Condensed Matter Physics & Semiconductors (AREA)
- General Physics & Mathematics (AREA)
- Manufacturing & Machinery (AREA)
- Computer Hardware Design (AREA)
- Microelectronics & Electronic Packaging (AREA)
- Power Engineering (AREA)
- Plasma & Fusion (AREA)
- Electron Beam Exposure (AREA)
- Drying Of Semiconductors (AREA)
Abstract
A preparation method of an InP-based nano periodic structure comprises the following steps: coating electron beam glue on a silicon-based InP substrate, placing a wafer coated with the electron beam glue in an oven for prebaking, designing a mask pattern by using a layout design tool according to the reduction of the width of a theoretical exposure line by a certain multiple, carrying out electron beam exposure and development on the substrate by using the mask pattern, etching InP in a methane and hydrogen mixed atmosphere by using an inductive coupling plasma technology, and obtaining an InP nano periodic structure with a target line width after removing residual glue by using wet cleaning. By the aid of the synergistic coupling effect of the two steps of mask pattern shrinkage and etching deposition reduction, the electron proximity effect in the exposure process can be counteracted, the electron beam exposure uniformity is improved, the tiled accumulation of deposits in plasma etching reaction can be reduced, the edge morphology of the nano structure is improved, and accordingly the target line width nano periodic structure is obtained.
Description
Technical Field
The invention relates to the technical field of semiconductor micro-nano processing, in particular to a method for preparing an InP-based nano periodic structure by using electron beam lithography.
Background
The InP semiconductor material has high electro-optic conversion efficiency and electron mobility, and is widely applied to the field of photoelectron. In the preparation process of the InP-based chip, an electron beam lithography technique is often used to prepare an InP nano-periodic structure. The line width of the nano periodic structure, the edge structure of the pattern and the cleanliness greatly influence the performance of the semiconductor device.
When an InP-based nano-periodic structure is prepared by an electron beam lithography technique, the width of an electron beam resist exposure stripe is increased due to the proximity effect of electron beams, which causes pattern distortion. In addition, during the subsequent plasma etching process using the electron beam resist as a mask, the deposition of reactive polymer on the resist mask may also cause distortion of the etching pattern and deformation of the edge structure.
Therefore, there is a need to develop a simple and effective method for preparing InP-based nanostructures that prevents distortion of electron beam exposure patterns and accumulation of resist mask polymers.
Disclosure of Invention
The invention aims to provide a preparation method of an InP-based nano periodic structure, which aims to solve the problems of glue pattern distortion after electron beam exposure and glue grating polymer deposition after plasma etching, so as to obtain the InP nano periodic structure with the target aspect ratio.
In order to achieve the above purpose, the technical scheme of the invention is as follows:
a preparation method of an InP-based nano periodic structure comprises the following steps:
the method comprises the following steps: coating electron beam glue on a silicon-based InP substrate;
step two: putting the wafer coated with the electron beam glue in an oven for pre-baking;
step three: designing a mask pattern by using a layout design tool according to a certain multiple of reduction of the width of a theoretical exposure line;
step four: carrying out electron beam exposure and development on the substrate by adopting the mask pattern;
step five: etching InP in a mixed atmosphere of methane and hydrogen by using an inductively coupled plasma technology;
step six: and (4) cleaning by a wet method to remove residual glue to obtain the InP nano periodic structure with the target line width.
Furthermore, in the first step, the silicon-based InP substrate is an InP epitaxial wafer and is prepared by a chemical vapor deposition method, and the thickness of InP is 200-600 nm.
Further, in the first step, the electron beam glue is ZEP520 or a diluent thereof, the glue homogenizing condition is 2000-7000rpm, and the glue homogenizing time is 30-60 s.
Further, the pre-drying condition in the step two is that the temperature is 180 ℃ on a hot plate, and the time is 3 min.
Further, the theoretical exposure line width in step three refers to the exposure line width calculated according to the formula [ period x (1-duty ratio) ] according to the specified duty ratio.
Further, the reduction in step three by a certain factor is to reduce the width of the theoretical exposure line by 0.1-0.3 times.
Further, in the fourth step, the acceleration voltage of the electron beam used for exposing the substrate by the electron beam is 100kV, the beam size is 10-20nA, and the exposure dose is 100-400 μ C.
Further, in the fourth step, paraxylene is used as a developing solution for the development time of 60s, isopropanol is used as a fixing solution for the fixing time of 30-60 s.
Further, the ratio of methane to hydrogen in the mixed gas in the fifth step is 1: 4.
Further, the wet cleaning in the sixth step is to soak for 2 hours by using dimethylacetamide.
Compared with the prior art, the invention has the beneficial technical effects that:
the method of the invention can offset the proximity effect of electrons in the exposure process and improve the exposure uniformity of the electron beam by shrinking the mask pattern and reducing the synergistic coupling effect of the two steps of etching and depositing, and can reduce the tiling and accumulation of sediments in the plasma etching reaction and improve the edge appearance of the nano structure, thereby obtaining the nano periodic structure with the target line width.
Detailed Description
Example 1
A preparation method of an InP-based nano periodic structure with a period of 100nm and an aspect ratio of 0.5 comprises the following steps:
a. coating electron beam glue on silicon-based InP substrate
The silicon-based InP substrate is an InP epitaxial wafer and is prepared by adopting a chemical vapor deposition method, and the thickness of InP is 200 nm. The electron beam glue is ZEP520 or a diluent thereof, the glue homogenizing condition is 2000rpm, and the glue homogenizing time is 30 s.
b. And (3) placing the wafer coated with the electron beam glue in an oven for pre-baking, wherein the pre-baking condition is that a hot plate is 180 ℃ and the time is 3 min.
c. Designing a mask pattern by using a layout design tool according to a certain multiple of reduction of theoretical exposure line width
The layout design tool is L-Edit, and the theoretical exposure line width calculated by using a formula [ period x (1-aspect ratio) ] is 50nm according to the period and the aspect ratio. The line width of the designed mask pattern is reduced by 0.1 times, namely 45 nm.
d. Performing electron beam exposure and development on the substrate using the mask pattern
The acceleration voltage of the electron beam used for exposing the substrate by the electron beam is 100kV, the beam size is 10nA, and the exposure dose is 100 mu C. The developing process adopts paraxylene as a developing solution and takes 60s, and adopts isopropanol as a fixing solution and takes 30 s.
e. InP is etched in a mixed atmosphere of methane and hydrogen by using an inductively coupled plasma technology, wherein the volume ratio of the methane to the hydrogen is 1: 4.
f. And (3) removing residual glue by wet cleaning, namely soaking for 2 hours by using dimethylacetamide, so as to obtain the InP nano periodic structure with the target line width.
Example 2
A preparation method of an InP-based nano periodic structure with a period of 200nm and an aspect ratio of 0.5 comprises the following steps:
a. coating electron beam glue on silicon-based InP substrate
The silicon-based InP substrate is an InP epitaxial wafer and is prepared by adopting a chemical vapor deposition method, and the thickness of InP is 600 nm. The electron beam glue is ZEP520 or its diluent, the spin condition is 7000rpm, the spin time is 60s
b. And (3) placing the wafer coated with the electron beam glue in an oven for pre-baking, wherein the pre-baking condition is that a hot plate is 180 ℃ and the time is 3 min.
c. Designing a mask pattern by using a layout design tool according to a certain multiple of reduction of theoretical exposure line width
The layout design tool is KLayout, and the theoretical exposure line width calculated by using a formula [ period x (1-aspect ratio) ] is 100nm according to the period and the aspect ratio. The line width of the designed mask pattern is reduced by 0.3 times, namely 70 nm.
d. Performing electron beam exposure and development on the substrate using the mask pattern
The acceleration voltage of the electron beam used for exposing the substrate by the electron beam is 100kV, the beam size is 20nA, and the exposure dose is 400 mu C. The developing process adopts paraxylene as a developing solution and takes 60s, and adopts isopropanol as a fixing solution and takes 60 s.
e. InP is etched in a mixed atmosphere of methane and hydrogen by using an inductively coupled plasma technology, wherein the volume ratio of the methane to the hydrogen is 1: 4.
f. And (3) removing residual glue by wet cleaning, namely soaking for 2 hours by using dimethylacetamide, so as to obtain the InP nano periodic structure with the target line width.
Claims (10)
1. A preparation method of an InP-based nano periodic structure is characterized by comprising the following steps:
the method comprises the following steps: coating electron beam glue on a silicon-based InP substrate;
step two: putting the wafer coated with the electron beam glue in an oven for pre-baking;
step three: designing a mask pattern by using a layout design tool according to a certain multiple of reduction of the width of a theoretical exposure line;
step four: carrying out electron beam exposure and development on the substrate by adopting the mask pattern;
step five: etching InP in a mixed atmosphere of methane and hydrogen by using an inductively coupled plasma technology;
step six: and (4) cleaning by a wet method to remove residual glue to obtain the InP nano periodic structure with the target line width.
2. The method as claimed in claim 1, wherein the InP-based nano-periodic structure is prepared by chemical vapor deposition of InP epitaxial wafer on the silicon-based InP substrate with a thickness of 200-600 nm.
3. The method as claimed in claim 1, wherein the electron beam resist in step one is ZEP520 or its diluent, the spin coating conditions are 2000-7000rpm, and the spin coating time is 30-60 s.
4. The method of claim 1, wherein the pre-baking in step two is performed at 180 ℃ for 3 min.
5. The method according to claim 1, wherein the theoretical width of the exposed line in step three is calculated according to the formula [ period x (1-aspect ratio) ] according to a specified aspect ratio.
6. The method according to claim 1, wherein the reduction in the third step is 0.1-0.3 times the theoretical exposure line width.
7. The method according to claim 1, wherein the substrate is exposed to electron beams with an acceleration voltage of 100kV, a beam current of 10-20nA, and an exposure dose of 100-.
8. The method of claim 1, wherein the developing step in the fourth step is performed with paraxylene as a developing solution for a developing time of 60s and isopropanol as a fixing solution for a fixing time of 30-60 s.
9. The method according to claim 1, wherein the volume ratio of methane to hydrogen in the mixed gas in step five is 1: 4.
10. The method of claim 1, wherein the wet cleaning in step six is performed by soaking in dimethylacetamide for 2 h.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110342868.XA CN113223936B (en) | 2021-03-30 | 2021-03-30 | Preparation method of InP-based nano periodic structure |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110342868.XA CN113223936B (en) | 2021-03-30 | 2021-03-30 | Preparation method of InP-based nano periodic structure |
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| Publication Number | Publication Date |
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| CN113223936A true CN113223936A (en) | 2021-08-06 |
| CN113223936B CN113223936B (en) | 2024-05-03 |
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2021
- 2021-03-30 CN CN202110342868.XA patent/CN113223936B/en active Active
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