CN111180578A - Phase change material nanowire and preparation method thereof - Google Patents
Phase change material nanowire and preparation method thereof Download PDFInfo
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- CN111180578A CN111180578A CN201911355126.XA CN201911355126A CN111180578A CN 111180578 A CN111180578 A CN 111180578A CN 201911355126 A CN201911355126 A CN 201911355126A CN 111180578 A CN111180578 A CN 111180578A
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- 239000002070 nanowire Substances 0.000 title claims abstract description 56
- 239000012782 phase change material Substances 0.000 title claims abstract description 52
- 238000002360 preparation method Methods 0.000 title claims abstract description 12
- 239000010410 layer Substances 0.000 claims abstract description 22
- 238000000034 method Methods 0.000 claims abstract description 15
- 239000011241 protective layer Substances 0.000 claims abstract description 8
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N silicon dioxide Inorganic materials O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 claims description 10
- 239000000463 material Substances 0.000 claims description 9
- 238000005229 chemical vapour deposition Methods 0.000 claims description 7
- 229910052814 silicon oxide Inorganic materials 0.000 claims description 7
- 238000000231 atomic layer deposition Methods 0.000 claims description 6
- 238000000151 deposition Methods 0.000 claims description 5
- 238000001755 magnetron sputter deposition Methods 0.000 claims description 5
- TWNQGVIAIRXVLR-UHFFFAOYSA-N oxo(oxoalumanyloxy)alumane Chemical compound O=[Al]O[Al]=O TWNQGVIAIRXVLR-UHFFFAOYSA-N 0.000 claims description 5
- 238000004549 pulsed laser deposition Methods 0.000 claims description 5
- 238000002207 thermal evaporation Methods 0.000 claims description 5
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 claims description 4
- 238000005566 electron beam evaporation Methods 0.000 claims description 4
- 238000001451 molecular beam epitaxy Methods 0.000 claims description 4
- 229910000480 nickel oxide Inorganic materials 0.000 claims description 4
- GNRSAWUEBMWBQH-UHFFFAOYSA-N oxonickel Chemical compound [Ni]=O GNRSAWUEBMWBQH-UHFFFAOYSA-N 0.000 claims description 4
- 229910052710 silicon Inorganic materials 0.000 claims description 4
- 239000010703 silicon Substances 0.000 claims description 4
- 230000008021 deposition Effects 0.000 claims description 3
- 239000010453 quartz Substances 0.000 claims description 3
- 239000000758 substrate Substances 0.000 claims description 3
- 229910005900 GeTe Inorganic materials 0.000 claims description 2
- 229910017629 Sb2Te3 Inorganic materials 0.000 claims description 2
- 229910052581 Si3N4 Inorganic materials 0.000 claims description 2
- GWEVSGVZZGPLCZ-UHFFFAOYSA-N Titan oxide Chemical compound O=[Ti]=O GWEVSGVZZGPLCZ-UHFFFAOYSA-N 0.000 claims description 2
- 238000009413 insulation Methods 0.000 claims description 2
- SOQBVABWOPYFQZ-UHFFFAOYSA-N oxygen(2-);titanium(4+) Chemical compound [O-2].[O-2].[Ti+4] SOQBVABWOPYFQZ-UHFFFAOYSA-N 0.000 claims description 2
- HQVNEWCFYHHQES-UHFFFAOYSA-N silicon nitride Chemical compound N12[Si]34N5[Si]62N3[Si]51N64 HQVNEWCFYHHQES-UHFFFAOYSA-N 0.000 claims description 2
- 238000004544 sputter deposition Methods 0.000 claims description 2
- OGIDPMRJRNCKJF-UHFFFAOYSA-N titanium oxide Inorganic materials [Ti]=O OGIDPMRJRNCKJF-UHFFFAOYSA-N 0.000 claims description 2
- 230000008020 evaporation Effects 0.000 claims 1
- 238000001704 evaporation Methods 0.000 claims 1
- 238000004519 manufacturing process Methods 0.000 abstract description 3
- 238000005285 chemical preparation method Methods 0.000 abstract description 2
- 238000000053 physical method Methods 0.000 abstract description 2
- 238000005516 engineering process Methods 0.000 description 10
- 230000008859 change Effects 0.000 description 7
- 239000004065 semiconductor Substances 0.000 description 6
- 238000003860 storage Methods 0.000 description 5
- 230000008569 process Effects 0.000 description 4
- 238000010438 heat treatment Methods 0.000 description 3
- 238000005240 physical vapour deposition Methods 0.000 description 3
- XKRFYHLGVUSROY-UHFFFAOYSA-N Argon Chemical compound [Ar] XKRFYHLGVUSROY-UHFFFAOYSA-N 0.000 description 2
- 239000000306 component Substances 0.000 description 2
- 239000000843 powder Substances 0.000 description 2
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 1
- 230000009471 action Effects 0.000 description 1
- 229910052786 argon Inorganic materials 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 239000002041 carbon nanotube Substances 0.000 description 1
- 229910021393 carbon nanotube Inorganic materials 0.000 description 1
- 239000008358 core component Substances 0.000 description 1
- 238000013500 data storage Methods 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000009826 distribution Methods 0.000 description 1
- 230000005684 electric field Effects 0.000 description 1
- 238000003912 environmental pollution Methods 0.000 description 1
- 239000007789 gas Substances 0.000 description 1
- 230000010354 integration Effects 0.000 description 1
- 239000012528 membrane Substances 0.000 description 1
- 230000005055 memory storage Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 239000002245 particle Substances 0.000 description 1
- 238000001259 photo etching Methods 0.000 description 1
- 230000002441 reversible effect Effects 0.000 description 1
- 238000001338 self-assembly Methods 0.000 description 1
- LIVNPJMFVYWSIS-UHFFFAOYSA-N silicon monoxide Chemical compound [Si-]#[O+] LIVNPJMFVYWSIS-UHFFFAOYSA-N 0.000 description 1
- 239000011863 silicon-based powder Substances 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 230000007704 transition Effects 0.000 description 1
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- H—ELECTRICITY
- H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
- H10N—ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
- H10N70/00—Solid-state devices without a potential-jump barrier or surface barrier, and specially adapted for rectifying, amplifying, oscillating or switching
- H10N70/801—Constructional details of multistable switching devices
- H10N70/881—Switching materials
- H10N70/882—Compounds of sulfur, selenium or tellurium, e.g. chalcogenides
- H10N70/8828—Tellurides, e.g. GeSbTe
-
- H—ELECTRICITY
- H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
- H10N—ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
- H10N70/00—Solid-state devices without a potential-jump barrier or surface barrier, and specially adapted for rectifying, amplifying, oscillating or switching
- H10N70/011—Manufacture or treatment of multistable switching devices
- H10N70/021—Formation of the switching material, e.g. layer deposition
Abstract
The invention discloses a phase-change material nanowire and a preparation method thereof, wherein the preparation method comprises the following steps: and loading a layer of phase change material on the outer surface of the insulated nanowire, and optionally loading a protective layer on the outer surface of the phase change material to form a limiting structure of the phase change material. The invention adopts a physical method to prepare the phase-change material nanowire, avoids various pollutions caused by a chemical preparation method, and prepares the phase-change material nanowire cleanly and reliably. The method for preparing the phase-change material nanowire is flexible and controllable in diameter, simple and easy to implement, and can be used for assembling the phase-change memory from bottom to top, manufacturing the phase-change memory in a micro mode and the like.
Description
Technical Field
The invention belongs to the technical field of nano processing, and relates to a phase change material nanowire and a preparation method thereof.
Background
With the rapid development of the semiconductor industry, the size of semiconductor devices tends to be smaller and smaller due to the continuous shrinkage of semiconductor process nodes, and the semiconductor memory chip, as a core component of a large-scale integrated circuit, occupies more than one third of the market share of the integrated circuit chip around the world. Smaller memory sizes are needed to meet future demands for high density memory storage devices. But the development of flash memory technology (one type of non-volatile memory) that is currently widely used to store data has met with a bottleneck. Firstly, in the aspect of reliability, the erasable frequency of a flash memory is only 10^ 6; in the writing time, the flash memory is written in by taking block as a unit, so that the writing time of the flash memory is microsecond magnitude; most importantly, when the photoetching limit node is below 22nm, the leakage current of the flash memory is too large, the stability is greatly limited, and the cell size of the flash memory is difficult to further shrink, so that the development of the flash memory is greatly limited.
New semiconductor memory technologies that are currently receiving wide attention include 3D-NANAD flash memory technology, Resistive Random Access Memory (RRAM) technology, magnetic memory (MRAM) technology, ferroelectric memory (FeRAM) technology, and phase change memory (PCRAM) technology. Compared with other novel semiconductor storage technologies, the phase change memory based on the phase change storage technology has the advantages of nonvolatility, good micro performance, long cycle life (the erasing and writing times are more than 10^ 6), high-speed reading (nanosecond magnitude), multistage storage and the like, is considered as the most potential next generation non-volatile storage technology, and realizes the mass production of small batches at present.
The phase-change material is used as a storage medium of the PCRAM, and the data storage of logic '0' and '1' is realized by reversible phase change between an amorphous state (RESET, high resistance) and a crystalline state (SET, low resistance) under the action of an electric field. Rapid transition of the phase change material between the two resistance states can be achieved by current-induced joule heating. The phase-change memory material is the core of the PCRAM, the size of the phase-change memory material directly determines the size of the PCRAM, and the phase-change material under the nanometer level has the performance advantages of low power consumption, high-speed memory and the like, thereby being beneficial to further high integration of an integrated circuit. Therefore, the preparation of nano-scale phase change memory materials is meaningful and indispensable.
Since the advent of nanowires and carbon nanotubes in the nano field, various nanowires have been successively prepared, such as silicon oxide nanowires, aluminum oxide nanowires, etc., and the preparation of nano-scale materials from nanowires has been widely studied and used to prepare electronic devices, which allow the self-assembly of integrated circuits from bottom to top. Therefore, in order to prepare the nano-scale phase change memory material, further reduce the size of the PCRAM and fully exert the performance advantages of the PCRAM, it is extremely important to explore the preparation of the nano-wire of the phase change memory material.
The existing chemical method for preparing the nanowire has complex process and serious environmental pollution, so that the exploration of a physical method for preparing the phase-change material nanowire is necessary and meaningful.
Disclosure of Invention
The invention aims to provide a phase-change material nanowire and a preparation method thereof.
The specific technical scheme for realizing the purpose of the invention is as follows:
a method for preparing phase change material nano-wires comprises the following steps: loading one or more layers of phase change materials on the surface of the insulated nanowire to obtain the phase change material nanowire; or after one or more layers of phase change materials are loaded on the surface of the insulated nanowire, loading a layer of insulated protective layer on the phase change materials to obtain the phase change material nanowire; wherein:
the phase change material is ternary Ge2Sb2Te、GeSb2Te4、GeSb4Te7Binary GeTe or Sb2Te3；
The phase change material layer or layers are loaded, and the outer surface of the insulated nanowire is coated with the phase change material layer or layers in a magnetron sputtering (PVD) mode, a Pulsed Laser Deposition (PLD) mode or an electron beam evaporation sputtering mode; or growing a phase change material film layer by adopting Molecular Beam Epitaxy (MBE), Chemical Vapor Deposition (CVD) or Atomic Layer Deposition (ALD) to enable the phase change material film to be coated on the outer surface of the insulated nanowire; or the silicon substrate with the phase-change film material grown thereon and the insulated nanowire are sealed in a vacuum quartz tube by adopting a thermal evaporation method, and the phase-change material is heated to volatilize so as to be coated on the outer surface of the insulated nanowire;
the insulating protective layer is made of silicon oxide, nickel oxide, titanium oxide, aluminum oxide or silicon nitride;
the load insulation protection layer is coated on the outer surface of the phase change material by adopting magnetron sputtering (PVD), Molecular Beam Epitaxy (MBE), Chemical Vapor Deposition (CVD), Atomic Layer Deposition (ALD), Pulsed Laser Deposition (PLD), electron beam evaporation or thermal evaporation.
The insulated nanowires are silicon oxide nanowires, nickel oxide nanowires, titanium dioxide nanowires or aluminum oxide nanowires.
The thickness of the loaded phase-change material is 1-100 nm.
The thickness of the insulating protective layer is 1-100 nm.
A phase change material nanowire prepared by the method.
The preparation method of the phase-change material nanowire avoids various pollutions caused by a chemical preparation method, and the prepared phase-change material nanowire is clean and reliable. The method for preparing the phase-change material nanowire has the advantages of flexible and controllable diameter, simple and easy realization, can be used for assembling the phase-change memory from bottom to top, and the micro-manufacturing of the phase-change memory, and has high industrial utilization value.
Drawings
FIG. 1 is a schematic cross-sectional view and a schematic plan view of a nanowire for depositing a phase-change material according to example 1 of the present invention;
FIG. 2 is a schematic cross-sectional view and a schematic plan view of a nanowire for depositing a phase change material and an insulating protective layer according to example 1 of the present invention;
fig. 3 is a physical diagram of a nanowire only deposited with a phase-change material according to embodiment 2 of the present invention.
Detailed Description
The essential features and advantages of the invention will be further elucidated by the following examples, which are to be construed as merely illustrative, but not limitative of the scope of the invention.
Example 1
The embodiment provides a preparation method of a phase-change material nanowire, which comprises the following specific steps:
step 1) adopting a thermal evaporation method, placing silicon (Si) powder in a quartz tank, wherein the distance between the silicon (Si) powder and a carrier is about 0.5mm, controlling the particle size and the distribution of silicon oxide nanowires by changing gas pressure and heating temperature, placing the Si powder in a tube furnace with the temperature of 1200 ℃ for heating and decomposing under the protection of 300Torr argon, and then collecting a layer of silicon oxide (SiO) on a carrier membrane2) A nanowire.
Step 2) preparing the 30nm SiO by using a magnetron sputtering (PVD) process in the step 1)2On the basis of nano wire, covering Ge2Sb2Te5Thickness of 50nm, the structure after deposition is shown in fig. 1, wherein, (a) is a plan view; (b) is a cross-sectional view.
Step 3) utilizing a CVD process, and preparing the Ge in the step 2)2Sb2Te5On the basis of the layer, SiN is coated, the thickness is 50nm, and the structure after deposition is shown as figure 2, wherein (a) is a plan view; (b) is a cross-sectional view.
Example 2
The difference between embodiment 2 and embodiment 1 is that only the phase change material layer is deposited with a thickness of 30nm, other steps are the same, and are not described herein again, and Ge is prepared2Sb2Te5The nanowire is shown in fig. 3.
The above embodiments are only used for illustrating the technical solutions of the present invention and are not limited. Variations and modifications of the embodiments disclosed herein are possible, and alternative and equivalent various components of the embodiments will be apparent to those skilled in the art. It will be clear to those skilled in the art that the present invention may be embodied in other forms, structures, arrangements, proportions, and with other substrates, materials, and components, without departing from the spirit or essential characteristics thereof. Any technical solutions that do not depart from the spirit and scope of the present invention should be construed as being included therein.
Claims (4)
1. A method for preparing phase change material nanowires is characterized by comprising the following steps: loading one or more layers of phase change materials on the surface of the insulated nanowire to obtain the phase change material nanowire; or after one or more layers of phase change materials are loaded on the surface of the insulated nanowire, loading a layer of insulated protective layer on the phase change materials to obtain the phase change material nanowire; wherein:
the phase change material is ternary Ge2Sb2Te、GeSb2Te4、GeSb4Te7Binary GeTe or Sb2Te3；
The phase-change material layer or layers are loaded, and the phase-change material layer or layers are coated on the outer surface of the insulated nanowire in a magnetron sputtering mode, a pulse laser deposition mode, an electron beam evaporation sputtering mode or an evaporation mode; or growing a phase change material film layer by adopting molecular beam epitaxy, chemical vapor deposition or atomic layer deposition to coat the outer surface of the insulated nanowire; or the silicon substrate with the phase-change film material grown thereon and the insulated nanowire are sealed in a vacuum quartz tube by adopting a thermal evaporation method, and the phase-change material is heated to volatilize so as to be coated on the outer surface of the insulated nanowire;
the insulating protective layer is made of silicon oxide, nickel oxide, titanium oxide, aluminum oxide or silicon nitride;
the load insulation protection layer is coated on the outer surface of the phase-change material by adopting magnetron sputtering, molecular beam epitaxy, chemical vapor deposition, atomic layer deposition, pulsed laser deposition, electron beam evaporation or thermal evaporation.
2. The method of claim 1, wherein the insulated nanowires are silicon oxide nanowires, nickel oxide nanowires, titanium dioxide nanowires, or aluminum oxide nanowires.
3. The preparation method according to claim 1, wherein the thickness of the loaded phase-change material is 1-100nm, and the thickness of the insulating protective layer is 1-100 nm.
4. A phase change material nanowire made by the method of claim 1.
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| CN1599068A (en) * | 2004-08-13 | 2005-03-23 | 中国科学院上海微系统与信息技术研究所 | Phase transformation micro, nano electronic memory device and manufacturing method |
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| CN101009214A (en) * | 2001-03-30 | 2007-08-01 | 加利福尼亚大学董事会 | Methods of fabricating nanostructures and nanowires and devices fabricated therefrom |
| US20080017842A1 (en) * | 2006-07-20 | 2008-01-24 | Thomas Happ | Phase change memory cell including nanocomposite insulator |
| CN101299453A (en) * | 2008-06-13 | 2008-11-05 | 中国科学院上海微系统与信息技术研究所 | Nano composite phase-changing material and preparation method thereof |
| CN101587905A (en) * | 2008-05-22 | 2009-11-25 | 上海市纳米科技与产业发展促进中心 | Phase change nanometer transistor unit device and manufacturing method thereof |
| CN102117823A (en) * | 2010-11-04 | 2011-07-06 | 中国科学院上海微系统与信息技术研究所 | Resistance conversion storage nano-structure and self-aligning manufacturing method thereof |
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2019
- 2019-12-25 CN CN201911355126.XA patent/CN111180578A/en active Pending
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101009214A (en) * | 2001-03-30 | 2007-08-01 | 加利福尼亚大学董事会 | Methods of fabricating nanostructures and nanowires and devices fabricated therefrom |
| CN1599068A (en) * | 2004-08-13 | 2005-03-23 | 中国科学院上海微系统与信息技术研究所 | Phase transformation micro, nano electronic memory device and manufacturing method |
| CN1801501A (en) * | 2005-11-25 | 2006-07-12 | 中国科学院上海微系统与信息技术研究所 | Method for preparing phase-change memory device unit using chalcogenide compound nanometer material |
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Application publication date: 20200519 |