CN105040096A - Novel spiral GaN monocrystal nanowire and preparation method thereof - Google Patents
Novel spiral GaN monocrystal nanowire and preparation method thereof Download PDFInfo
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Abstract
The invention relates to a novel spiral GaN monocrystal nanowire and a preparation method thereof, and belongs to the technical field of semiconductor nanomaterial production. According to the preparation method, a chemical vapor deposition method is adopted to prepare the spiral GaN nanowire, and the preparation method comprises the following steps: weighing a proper amount of Ga, and putting the Ga in a ceramic boat; putting the ceramic boat in the middle of a horizontal tube furnace; weighing a proper amount of MoCl5, and putting the MoCl5 in the ceramic boat; putting the ceramic boat in the upstream position 20-30 cm away from a middle temperature zone; at the same time, putting a gilded Si substrate in the position 20-25 cm away from the middle temperature zone; sealing the horizontal tube furnace; starting a vacuum system; when the vacuum degree in the furnace reaches 1*10<-3> Pa, introducing Ar gas; heating and keeping the temperature; adjusting the Ar gas flow rate to 10 sccm, and turning on an ammonia airflow valve for introducing ammonia gas at the same time; after reacting for 1-2 h, stopping ammonia gas introduction, and cooling to room temperature; finally, collecting a layer of sediment on the Si substrate, namely, the spiral GaN monocrystal nanowire. The preparation method is easy to implement, simple in technology and relatively low in cost.
Description
Technical field
The present invention relates to nano material and preparation method thereof, be specifically related to a kind of Novel spiral GaN monocrystal nanowire and preparation method thereof, relate to the preparation research of semiconductor material, belong to semiconductor nano material production technical field.
Background technology
GaN is a kind of semi-conductor with larger energy gap, belongs to the row of so-called wide bandgap semiconductor, and it is the excellent material of microwave power transistor, is also a kind of semi-conductor with significant application value in blue light luminescent device.GaN is the compound of stabilizer pole, and be again hard materials with high melting point, fusing point is about 1700 DEG C; GaN has high degree of ionization, is the highest in III-V compounds of group; At atmosheric pressure, GaN crystal is generally hexagonal wurtzite structure; It has 4 atoms in a cellular, and atomic volume is approximately the half of GaAs; Again because its hardness is high, it is a kind of good coating protection material.The research and apply of GaN material is forward position and the focus of the research of current global semiconductor, it is the novel semiconductor material of development microelectronic device, opto-electronic device, and together with the semiconductor material such as SIC, diamond, being described as is third generation semiconductor material after first-generation Ge, Si semiconductor material, s-generation GaAs, InP compound semiconductor materials.It has character and the strong Radiation hardness such as wide direct band gap, strong atomic bond, high thermal conductivity, chemical stability good (hardly by any acid corrosion), has wide prospect in photoelectron, high temperature high power device and high frequency microwave device application aspect.
GaN base dilute magnetic semiconductor has premium properties in optics, electricity, magnetics etc., and be with a wide range of applications based on the optics of GaN base dilute magnetic semiconductor material exploitation, electricity, magnetic component, its portioned product occupies a tiny space in the market.In recent years, about the various patterns of GaN nanostructure have had a large amount of report, as GaN nano-powder, nano wire, nanotube, nano belt, nanometer sheet, nano thin-film, triangular prism; Low dimensional structures GaN material can effectively reduce taking up room of device, and one-dimensional nano line can play a significant role in assemble nanometer device.The present invention mainly uses the MoCl of different concns at reaction source
5achieve the preparation of spirrillum GaN monocrystal nanowire.
Investigator is had to utilize chemical Vapor deposition process to have studied MnCl
2, CoCl
2and CrCl
3impact when growing GaN nano wire, and done the research of related mechanism aspect, insert the difference of the transition metal chloride substance withdrawl syndrome in tube furnace before the reaction, also respective change can be there is in the microscopic appearance of the GaN nanostructure grown, as there is hexagon, trilateral and square cross section, but do not relate to Z-shaped nano wire in this change, helicoidal structure occurs, consult NanoLetters, the 8th volume (the 9th phase) the 2674 to 2681 page.
From literature survey and related data, not yet report utilizes chemical Vapor deposition process to prepare a large amount of spirrillum GaN nano wire at present, utilize this legal system for spirrillum GaN nano wire, the sample purity obtained is higher, under x-ray diffractometer limit of detection condition, does not find second-phase, and method is simple, sample obtains and is easy to repetition, little to environmental hazard, be easy to the advantages such as popularization, therefore can be widely used in the preparation of III-V race's semi-conductor.
Summary of the invention
The object of this invention is to provide a kind of Novel spiral GaN monocrystal nanowire and preparation method thereof, there is spiral helicine GaN nano wire method, to fill up spirrillum GaN nano wire microscopic appearance technological gap by chemical Vapor deposition process preparation; The present invention adopts metal Ga and NH
3gas respectively as Ga source and N source, MoCl
5powder as Mo source, with obtain controllable growth spirrillum GaN nano wire; Present method is simple, cost is low, and all raw materials are all very common, can realize suitability for industrialized production.
For achieving the above object, the technical solution used in the present invention is as follows:
A preparation method for Novel spiral GaN monocrystal nanowire, comprises the steps:
(1) taking metal Ga is contained in ceramic boat, and be placed on the middle part of horizontal pipe furnace, Mo/Ga=0.15 ~ 0.20 takes MoCl in molar ratio
5powder is contained in ceramic boat, is placed in the upstream position apart from center warm area 20 ~ 30cm, simultaneously at the Si substrate placing gold-plated process apart from 20 ~ 25cm position, warm area downstream, center, and sealed horizontal tube furnace;
(2) vacuum system is started, vacuum tightness to 1 × 10 in stove
-3during Pa, pass into Ar gas, Ar entraining air stream speed is 10 ~ 80sccm, is heated to 940 ~ 1050 DEG C, is incubated 0.5 ~ 2 hour, turns on ammonia draught damper simultaneously and pass into NH with 15 ~ 100sccm flow velocity
3gas, after 1 ~ 2h is carried out in reaction, disconnect ammonia and be cooled to room temperature, finally collect a surface sediments on a si substrate, be spirrillum GaN monocrystal nanowire, the GaN nano wire prepared presents spiral shape, and is single crystal structure.
The invention has the beneficial effects as follows: direct employing chemical Vapor deposition process of the present invention prepares spirrillum GaN nano wire, and still belong to the first time report, adds the variation of GaN nano wire microscopic appearance, for preparation GaN photoelectric device adds selectable range; The method preparation technology is simple, cost is low, be easy to control; Experimental product purity compared with high, good uniformity, controllability is good, environmental pollution is little, be easy to promote, thus there is important researching value and wide application prospect, the preparation of III-V race's semi-conductor can be widely used in.
figure of description
The SEM figure of Fig. 1 spirrillum GaN nano wire;
The single spirrillum GaN nano wire SEM of Fig. 2 schemes;
The TEM figure of Fig. 3 sample;
The TEM figure of Fig. 4 sample;
The HRTEM figure of Fig. 5 sample;
The SAED figure of Fig. 6 sample;
The XRD figure of Fig. 7 sample.
Embodiment
Be described in further details the present invention below by example, these examples are only used for the present invention is described, do not limit the scope of the invention.
Embodiment 1
A preparation method for Novel spiral GaN nano wire, is realized by following technique: utilize chemical Vapor deposition process to prepare Novel spiral GaN nano wire, adopts metal Ga and NH
3gas respectively as Ga source and N source, MoCl
5powder is as Mo source, and take appropriate metal Ga and be contained in ceramic boat, be placed on the middle part of horizontal pipe furnace, Mo/Ga=0.16 takes appropriate MoCl in molar ratio
5be contained in ceramic boat, be placed in the upstream position apart from center warm area 20 ~ 30cm, simultaneously at the Si substrate placing gold-plated process apart from warm area 20 ~ 25cm position, center, sealed horizontal tube furnace; Start vacuum system, vacuum tightness to 1 × 10 in stove
-3during Pa; Pass into Ar gas, when being heated to 970 degrees Celsius, by Ar controlled atmosphere to 10sccm, turn on ammonia draught damper to pass into 30sccm flow velocity simultaneously, after 1h is carried out in reaction, disconnect ammonia and be cooled to room temperature, finally collect a surface sediments on a si substrate, be spirrillum GaN monocrystal nanowire.
The volution GaN nano wire of gained, at the growth tail end of straight nano wire, all growth has spirrillum GaN nano wire, and its radial dimension is about about 70nm, the surperficial phase relative smooth of nano wire, as shown in Figure 1, Figure 2, Figure 3 and Figure 4; Sample has obvious lattice fringe, and obvious diffraction spot, as shown in Figure 5 and Figure 6, shows that sample is single crystal structure; The XRD diffract spectral line of sample shows that it is wurtzite GaN structure (ICDD-PDFNo.50-0792), as Fig. 7.
As can be seen from above example, the spirrillum GaN nano wire adopting chemical Vapor deposition process to prepare has room-temperature ferromagnetic, the feature that its product uniformity is good, controllability is good, technique is simple, cost is low, thus has important researching value and wide application prospect.
Embodiment 2
Preparation spirrillum GaN nano wire, the horizontal pipe furnace that system for use in carrying is heated by Si-Mo rod, air-channel system and vacuum system form, and utilize chemical Vapor deposition process to prepare novel GaN spirrillum nano wire, adopt metal Ga and NH
3gas respectively as Ga source and N source, MoCl
5powder is as Mo source;
(1) taking metal Ga is contained in ceramic boat, and be placed on the middle part of horizontal pipe furnace, Mo/Ga=0.15 takes MoCl in molar ratio
5powder is contained in ceramic boat, is placed in the upstream position apart from center warm area 20 ~ 30cm, simultaneously at the Si substrate placing gold-plated process apart from 20 ~ 25cm position, warm area downstream, center, and sealed horizontal tube furnace;
(2) vacuum system is started, vacuum tightness to 1 × 10 in stove
-3during Pa, pass into Ar gas, Ar entraining air stream speed is 10sccm, is heated to 940 DEG C, is incubated 2 hours, turns on ammonia draught damper simultaneously and pass into NH with 15sccm flow velocity
3gas, after 2h is carried out in reaction, disconnect ammonia and be cooled to room temperature, finally collect a surface sediments on a si substrate, be spirrillum GaN monocrystal nanowire, the GaN nano wire prepared presents spiral shape, and is single crystal structure.
Embodiment 3
Preparation spirrillum GaN nano wire, the horizontal pipe furnace that system for use in carrying is heated by Si-Mo rod, air-channel system and vacuum system form, and utilize chemical Vapor deposition process to prepare novel GaN spirrillum nano wire, adopt metal Ga and NH
3gas respectively as Ga source and N source, MoCl
5powder is as Mo source;
(1) taking metal Ga is contained in ceramic boat, and be placed on the middle part of horizontal pipe furnace, Mo/Ga=0.20 takes MoCl in molar ratio
5powder is contained in ceramic boat, is placed in the upstream position apart from center warm area 20 ~ 30cm, simultaneously at the Si substrate placing gold-plated process apart from 20 ~ 25cm position, warm area downstream, center, and sealed horizontal tube furnace;
(2) vacuum system is started, vacuum tightness to 1 × 10 in stove
-3during Pa, pass into Ar gas, Ar entraining air stream speed is 80sccm, is heated to 1050 DEG C, is incubated 0.5 hour, turns on ammonia draught damper simultaneously and pass into NH with 100sccm flow velocity
3gas, after 1h is carried out in reaction, disconnect ammonia and be cooled to room temperature, finally collect a surface sediments on a si substrate, be spirrillum GaN monocrystal nanowire, the GaN nano wire prepared presents spiral shape, and is single crystal structure.
Embodiment 4
Preparation spirrillum GaN nano wire, the horizontal pipe furnace that system for use in carrying is heated by Si-Mo rod, air-channel system and vacuum system form, and utilize chemical Vapor deposition process to prepare novel GaN spirrillum nano wire, adopt metal Ga and NH
3gas respectively as Ga source and N source, MoCl
5powder is as Mo source;
(1) taking metal Ga is contained in ceramic boat, and be placed on the middle part of horizontal pipe furnace, Mo/Ga=0.18 takes MoCl in molar ratio
5powder is contained in ceramic boat, is placed in the upstream position apart from center warm area 20 ~ 30cm, simultaneously at the Si substrate placing gold-plated process apart from 20 ~ 25cm position, warm area downstream, center, and sealed horizontal tube furnace;
(2) start vacuum system, in stove, vacuum tightness is down to 1 × 10
-3during Pa, pass into Ar gas, Ar entraining air stream speed is 40sccm, is heated to 1000 DEG C, is incubated 1 hour, turns on ammonia draught damper simultaneously and pass into NH with 60sccm flow velocity
3gas, after 1.5h is carried out in reaction, disconnect ammonia and be cooled to room temperature, finally collect a surface sediments on a si substrate, be spirrillum GaN monocrystal nanowire, the GaN nano wire prepared presents spiral shape, and is single crystal structure.
Embodiment 5
Preparation spirrillum GaN nano wire, the horizontal pipe furnace that system for use in carrying is heated by Si-Mo rod, air-channel system and vacuum system form, and utilize chemical Vapor deposition process to prepare novel GaN spirrillum nano wire, adopt metal Ga and NH
3gas respectively as Ga source and N source, MoCl
5powder is as Mo source;
(1) taking metal Ga is contained in ceramic boat, and be placed on the middle part of horizontal pipe furnace, Mo/Ga=0.19 takes MoCl in molar ratio
5powder is contained in ceramic boat, is placed in the upstream position apart from center warm area 20 ~ 30cm, simultaneously at the Si substrate placing gold-plated process apart from 20 ~ 25cm position, warm area downstream, center, and sealed horizontal tube furnace;
(2) start vacuum system, in stove, vacuum tightness is down to 1 × 10
-3during Pa, pass into Ar gas, Ar entraining air stream speed is 60sccm, is heated to 1020 DEG C, is incubated 1.5 hours, turns on ammonia draught damper simultaneously and pass into NH with 80sccm flow velocity
3gas, after 1h is carried out in reaction, disconnect ammonia and be cooled to room temperature, finally collect a surface sediments on a si substrate, be spirrillum GaN monocrystal nanowire, the GaN nano wire prepared presents spiral shape, and is single crystal structure.
Claims (5)
1. a preparation method for Novel spiral GaN monocrystal nanowire, is characterized in that: utilize chemical Vapor deposition process to prepare Novel spiral GaN nano wire; Adopt metal Ga and NH
3gas respectively as Ga source and N source, MoCl
5as Mo source, concrete grammar comprises the steps:
(1) taking metal Ga is contained in ceramic boat, and be placed on the middle part of horizontal pipe furnace, Mo/Ga=0.15 ~ 0.20 takes MoCl in molar ratio
5be contained in ceramic boat, be placed in the upstream position apart from center warm area 20 ~ 30cm, simultaneously at the Si substrate placing gold-plated process apart from 20 ~ 25cm position, warm area downstream, center, sealed horizontal tube furnace;
(2) vacuum system is started, vacuum tightness to 1 × 10 in stove
-3during Pa, pass into Ar gas, heating and thermal insulation, by Ar controlled atmosphere to 10sccm, turn on ammonia draught damper simultaneously and pass into NH
3gas, after 1 ~ 2h is carried out in reaction, disconnects ammonia and is cooled to room temperature, finally collecting a surface sediments on a si substrate, be spirrillum GaN monocrystal nanowire.
2. the preparation method of a kind of Novel spiral GaN monocrystal nanowire according to claim 1, is characterized in that: the temperature of step (2) described heating is 940 ~ 1050 DEG C, is incubated 0.5 ~ 2 hour.
3. the preparation method of a kind of Novel spiral GaN monocrystal nanowire according to claim 1, is characterized in that: the airflow rate of the described Ar gas of step (2) is 10 ~ 80sccm, NH
3entraining air stream speed is 15 ~ 100sccm.
4. a Novel spiral GaN monocrystal nanowire, is characterized in that: utilize method described in claim 1 ~ 3 any one to prepare.
5. a kind of Novel spiral GaN monocrystal nanowire according to claim 4, is characterized in that: Novel spiral GaN monocrystal nanowire presents spiral shape, and is single crystal structure.
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107699863A (en) * | 2017-09-19 | 2018-02-16 | 北京工业大学 | A kind of method that MPCVD prepares GaN nano wire |
| CN107910243A (en) * | 2017-10-18 | 2018-04-13 | 中国科学院半导体研究所 | The method for preparing GaN nano wire on substrate |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107699863A (en) * | 2017-09-19 | 2018-02-16 | 北京工业大学 | A kind of method that MPCVD prepares GaN nano wire |
| CN107910243A (en) * | 2017-10-18 | 2018-04-13 | 中国科学院半导体研究所 | The method for preparing GaN nano wire on substrate |
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