CN103539122A - Silicon carbide preparation method - Google Patents
Silicon carbide preparation method Download PDFInfo
- Publication number
- CN103539122A CN103539122A CN201310477645.XA CN201310477645A CN103539122A CN 103539122 A CN103539122 A CN 103539122A CN 201310477645 A CN201310477645 A CN 201310477645A CN 103539122 A CN103539122 A CN 103539122A
- Authority
- CN
- China
- Prior art keywords
- silicon carbide
- preparation
- carbon source
- silicon
- feed particles
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Images
Abstract
The invention provides a preparation method of silicon carbide, and belongs to the technical field of semiconductor preparation. The invention aims at solving a problems of severe pollution and poor silicon carbide product purity of existing silicon carbide preparation methods. The method comprises the steps that: silica or metal silicon or a mixture of the two is completely coated by using a carbon source comprising carbon element, and raw material particles are prepared; and the raw material particles are subjected to a reaction under high temperature, such that silicon carbide is produced. The invention also discloses a method for preparing silicon carbide by using a device equipped with a plasma generation device. The invention also comprises a method for directly adding the carbon source and silica or metal silicon or the mixture of the two into plasma flame for carrying out a heating reaction and further producing silicon carbide. The invention also comprises a silicon carbide preparation method comprising a purification step. With the method, environment pollution can be avoided, and silicon carbide purity can be improved.
Description
Technical field
The invention belongs to semi-conductor preparing technical field, relate to a kind of as the raw-material silicon carbide preparation method of semiconductor device substrates.
Background technology
Existing silicon carbide preparation method adopts at the peripheral layer overlay carbon of quartz sand, then at carbon, repave last layer quartz sand outward, repave the carbon-coating that last layer coal or refinery coke are raw material, the quartz sand of every layer of laying is different with carbon-coating thickness, lay the 7 days above time of rear heat, by silicon-dioxide and carbon reaction, form SiC, but in quartz sand and carbon, also has a large amount of metallic impurity ash contents, under heat environment, also there is chemical reaction in these impurity, generate yellow, the red smog that waits multiple color, and these impurity also have considerable influence to the purity of SiC itself.After this, SiC is pulverized after sorting and pickling and packed.The silicon carbide of making is by this method very large to the pollution of environment, and the purity of silicon carbide is not high yet.
Summary of the invention
The present invention is directed to prior art and have the problems referred to above, proposed a kind of preparation method of silicon carbide, by this preparation method, can avoid the pollution to environment, can also improve the purity of silicon carbide.
The present invention realizes by following technical proposal: a kind of preparation method of silicon carbide, it is characterized in that, and the method comprises by the carbon source of carbon elements and wraps silica or Pure Silicon Metal or both mixtures completely and make feed particles; Feed particles is at high temperature reacted to Formed SiClx.
Be different from existing rough type preparation method, the present invention has carried out preprocessing to raw material, is about to carbon source and wraps silica completely, or wrap Pure Silicon Metal by carbon source, or by carbon source, wrap silica and Pure Silicon Metal mixture, then make the feed particles more bigger than sand.By this preprocessing step, the distance that can be just carbon source and silica or Pure Silicon Metal is more approaching, contact area is larger, thereby at high temperature can react fully and speed of response fast, and then improved production efficiency prepared by silicon carbide, and the pollution of the impurity that adopts this feed particles to produce can to avoid in carbon source to the silicon carbide generating.
In the preparation method of above-mentioned silicon carbide, described carbon source is solid-state, is the material that carbon plays reduction reaction or a carburizing reagent in reacting with element silicon.As preferably, can adopt Powdered solid-state.
In the preparation method of above-mentioned silicon carbide, described carbon source is one or more mixing in graphite, wooden carbon, coke, refinery coke or powder timber.Under hot environment, these materials can produce carbon, and carbon all can react with silica or Pure Silicon Metal.
In the preparation method of above-mentioned silicon carbide, the maximum diagonal of described feed particles or maximum diameter are 0.001mm～5mm.Be greater than after 5mm, feed particles at high temperature reaction effect can reduce, and being less than 0.001mm can increase the preparation cost of original particle.Therefore within 0.001mm～5mm scope, be, preferred.Wherein 2-3mm is best scope, takes into account cost and efficiency.
In the preparation method of above-mentioned silicon carbide, described feed particles is that single silica or single metal silicon are wrapped in the feed particles in carbon source; Or described feed particles is integrated into a whole feed particles for several individual particles, and individual particle refers to that single silica or single metal silicon are wrapped in carbon source.
In the preparation method of above-mentioned silicon carbide; after described carbon source, silica or Pure Silicon Metal or both mixtures mix; add again binding agent and water to stir and dry, by tablets press, form and a plurality of silica or Pure Silicon Metal or both mixtures are wrapped in to the feed particles in carbon source.
In the preparation method of above-mentioned silicon carbide, in carbon source, add binding agent and water to stir to form mucus, the single silica of monolayer alignment or Pure Silicon Metal are immersed in in this mucus or directly, by mucus, by spraying method, forming single silica or Pure Silicon Metal or both mixtures is wrapped in the feed particles in carbon source.
In the preparation method of above-mentioned silicon carbide, the silicon carbide that it is 0.5-10% that described feed particles also comprises containing weight percent.In feed particles, add silicon carbide can play the effect that prevents that newly-generated silicon carbide from boning mutually.Feed particles comprises inner silica or Pure Silicon Metal and is wrapped in the carbon source outside silica or Pure Silicon Metal, includes binding liquid, timber and silicon carbide in carbon source.Timber plays time-lag action.
In the preparation method of above-mentioned silicon carbide, the element silicon in described feed particles and the mass ratio of carbon are 3:1～3:3.Element silicon is 3 parts, carbon be 1 part just can Formed SiClx, carbon can have sufficient carbon to react with element silicon during more than 1 part, but too much more than carbon after 3 parts, the impurity in carbon source too much and the purity of silicon carbide.
By above-mentioned preparation method, make after silicon carbide, the present invention has also further proposed to adopt the equipment that is equipped with plasma generator to produce silicon carbide.
A preparation method for silicon carbide, is characterized in that, the method comprises and adopts the equipment be equipped with plasma generator to produce silicon carbide.Plasma generator can generate the high temperature of 3000 degrees Celsius, with plasma generation equipment, as high temperature source, in silicon carbide preparation, be of the present invention pioneering, because the common silicon carbide mode of production can not adopt plasma generator to heat, can only heat with carbon-point.
In the preparation method of above-mentioned silicon carbide, feed particles joins in the inner or inner gas duct of plasma generator or outside its exit end increasing in addition of plasma generator approaches in the conduit of gas duct.Plasma generator inside has cavity and communicates with gas duct, and gas duct is for gases such as logical argon gas, thereby its outlet is divided into ion through high-voltage, produces plasma flame, and it is higher that plasma flame more approaches air outlet temperature.The preparation method of this silicon carbide joins above-mentioned feed particles from the cavity of the inside of plasma generator or inner gas duct, and then along with gravity fall is carried out reacting by heating to the air outlet of gas duct by plasma thermal-flame moment.Except this directly in original plasma generator incoming stock particle, can also improve by article on plasma generating unit, at inner several conduits that increase of plasma generator, conduit upper end port is opened in the upper end of plasma generator, and the lower end that lower end is opened in plasma generator communicates with gas duct.
When using plasma generator to add hot preparation silicon carbide as high temperature source, the present invention has also further proposed more multimode silicon carbide preparation method.
A preparation method for silicon carbide, is characterized in that, comprises carbon source and silica or Pure Silicon Metal or both mixtures are directly put into and in plasma flame, carry out reacting by heating and then Formed SiClx simultaneously.
Present method is that carbon source and silica or Pure Silicon Metal are directly put in plasma flame by passage separately simultaneously, afterwards just can Formed SiClx as long as guarantee to mix fully between the two in input.
In the preparation method of above-mentioned silicon carbide, described carbon source is the material that carbon plays reduction reaction or a carburizing reagent in reacting with element silicon.
In the preparation method of above-mentioned silicon carbide, described carbon source is gaseous carbon source, and gaseous carbon source is one or several mixing in hydrocarbon, hydrocarbon polymer, fluorocarbon or carbon chlorine compound.
In the preparation method of above-mentioned silicon carbide, described carbon source is solid-state carbon source, and solid-state carbon source is one or more mixing in graphite, pure carbon, coke, refinery coke or timber.
In the preparation method of above-mentioned silicon carbide, carbon source and silica or Pure Silicon Metal or both mixtures are made to feed particles and directly put into and in plasma flame, carry out reacting by heating.
In the preparation method of above-mentioned silicon carbide, described plasma flame is produced by more than one or one plasma generator.
In the preparation method of above-mentioned silicon carbide, plasma flame is greater than the speed ejection of 50 meter per seconds with speed.Metal oxide in carbon source can generally easily not removed on the surface of silicon carbide at silicon carbide internal diffusion, thereby and the metals like gold that metal oxide generates after reacting with carbon source belongs to the purity that aluminium affects silicon carbide in can being diffused into silicon carbide under hot environment.And the speed of plasma flame can produce air-flow faster, and these air-flows can make ash content metal or metal oxide that carbon source forms in reaction just be blown away before touching silicon carbide, can improve in this way the preparation purity of silicon carbide.
After in aforesaid method, for improving the purity of Formed SiClx, present method comprises a purification step.
A kind of preparation method of silicon carbide, it is characterized in that, present method comprises a purification step, the thermograde that formation temperature increases continuously in purification passage, the silicon carbide of interior metal impurities progressively gasifies respectively boiling point lower than the metallic impurity of silicon carbide through purification passage, after silicon carbide gasification, the silicon carbide of gasification is detached and forms solid-state silicon carbide.
By aforesaid method, produce after silicon carbide, because metal can enter in silicon carbide crystallization when manufacturing silicon carbide, metal oxide can not enter, therefore silicon carbide and inside still have impurity existence, therefore, contain in the method silicon carbide purification step, this purification step is being that silicon carbide is put in purification passage after surperficial pickling and washing, because temperature in purification passage is Gradient distribution, the silicon carbide of interior metal impurities first passes through the first area of thermograde, in reaching gradually the high temperature of 1500 degrees Celsius, most of metallic impurity of silicon carbide inside progressively gasify according to the boiling point of oneself, the metallic impurity of gasification are discharged in silicon carbide crystallization according to the principle of thermal perturbation in silicon carbide crystallization, as metals such as iron aluminium, entered again second area, high temperature by 2800 degrees Celsius gasifies silicon carbide, the metallic impurity of silicon carbide inside also will gasify, because proportion is different, most of silicon carbide concentrates in one deck, at this moment the silicon carbide of gasification is detached and form solid-state silicon carbide, so just can mention 99.99999% silicon carbide purity.
In the preparation method of above-mentioned silicon carbide, described thermograde is divided into several heating regions, and each heating region is heated by each heating unit.
In the preparation method of above-mentioned silicon carbide, in heating region, be provided with the air feed port that supplied gas flows into.The inflow direction of gas is contrary with the inflow direction of silicon carbide.The obstruction flowing into by gas, silicon carbide can be suspended in this region more for a long time, thereby can extend the time of purification.
In the preparation method of above-mentioned silicon carbide, at heating region, be provided with the air outlet for the gas in purification passage and/or powder outflow.
In the preparation method of above-mentioned silicon carbide, the length of described air outlet is 1cm～5cm.
Compared with prior art, the preparation method of this silicon carbide adopts feed particles as the mode of heating source and employing high temperature purification, to prepare silicon carbide as raw material, plasma generator, this method can be avoided the pollution to environment, can also improve the purity of silicon carbide.
Accompanying drawing explanation
Fig. 1, Fig. 2 and Fig. 3 are the feed particles in the preparation method of this silicon carbide.
Fig. 4 is the plasma generator adopting in the preparation method of this silicon carbide.
Fig. 5 is the equipment of plasma generator that is equipped with in the preparation method of this silicon carbide.
Fig. 6 is the another kind of equipment of plasma generator that is equipped with in the preparation method of this silicon carbide.
Fig. 7 is purifying plant in the preparation method of written or printed documents silicon carbide.
In figure, 1, silica; 2, carbon source; 3, feed particles; 41, cavity; 42, gas duct; 43, sleeve; 44, feed-pipe; 5, crucible; 6, lifting pin; 7, pallet; 8, cooling line; 81, cooling water inlet; 82, cooling water outlet; 9, gas is adjusted cylinder; 10, inlet mouth; 11, air outlet; 12, pod; 13, feed conduits; 14, exhaust-duct; 15, air-flow is adjusted cylinder; 16, Reaktionsofen; 161, gas feed one; 162, silicon carbide is collected mouth; 163, impurity is collected mouth; 164, venting port; 165, gas feed two; 166, gas feed three; 17, raw material supplying bucket; 18, speed regulator; 19, the first temperature province; 20, the second temperature province; 21, gas-sparging head.
Embodiment
Be below specific embodiments of the invention, and by reference to the accompanying drawings technical scheme of the present invention be further described, but the present invention is not limited to these embodiment.
Embodiment 1:
The preparation method of silicon carbide is that employing silicon-dioxide and pure carbon are raw material, and at high temperature silicon-dioxide is reduced by carbon, generates the silicon carbide of solid and the carbonic acid gas of gas, and gas and the powder of ash content, impurity are released.The temperature of this reaction and speed are decided by the distance length of the size of silicon-dioxide and the carbon of silicon-dioxide and reducing material: the less and silicon-dioxide of silicon-dioxide and carbon distance are shorter, and the temperature of reacting required is lower, and speed is faster.
For this reason, the present invention adopts following steps to realize the production of silicon carbide: by the carbon source of carbon elements, wrap silica 1 completely and make feed particles 3; Feed particles 3 is at high temperature reacted to Formed SiClx.The main component of silica 1 is silicon-dioxide.In this example, silica 1 can replace with Pure Silicon Metal, or replaces silica 1 to be all fine with silica 1 and Pure Silicon Metal mixture.
Specifically, as Figure 1-3, carbon source 2 is solid state powder shape, is the material that carbon plays reduction reaction or a carburizing reagent in reacting with element silicon.Carbon source 2 can be one or more mixing in graphite, wooden carbon, coke, refinery coke or powder timber.Under hot environment, these materials can produce carbon, and carbon all can react with silica or Pure Silicon Metal.In this example, adopt the mixture of graphite and powder timber as carbon source 2.Powder timber at high temperature can be produced carbon, because powder timber Formed element needs the regular hour, can control by the blending ratio of powder timber the speed of silicon carbide reactor like this.In a large amount of tests, it is the most suitable that the weight blending ratio of powder timber and graphite is controlled at 3:8.
The maximum diagonal of feed particles 3 or maximum diameter are 0.001mm～5mm.Be greater than after 5mm, feed particles 3 at high temperature reaction effect can reduce, and being less than 0.001mm can increase the preparation cost of original particle.Therefore within 0.001mm～5mm scope, be, preferred.Wherein 2-3mm is best scope, takes into account cost and efficiency.The silicon carbide that it is 0.5-10% that feed particles 3 also comprises containing weight percent.In feed particles 3, increase silicon carbide and can play the effect that the silicon carbide that prevents from generating bonds mutually.Element silicon in feed particles 3 and the mass ratio of carbon are 3:1～3:3.
Feed particles 3 is that single silica or single metal silicon are wrapped in the feed particles 3 in carbon source 2.This feed particles 3 is by add binding agent and water to stir to form mucus in carbon source 2, the single silica of monolayer alignment or Pure Silicon Metal is immersed in in this mucus or directly, by mucus, by spraying method, forming single silica or Pure Silicon Metal or both mixtures is wrapped in the feed particles 3 in carbon source 2.
Feed particles 3 can be also that several individual particles are integrated into a whole feed particles 3, and individual particle refers to that single silica or single metal silicon are wrapped in carbon source 2; After this feed particles 3 is mixed by carbon source 2, silica or Pure Silicon Metal or both mixtures; add again binding agent and water to stir and dry, by tablets press, form and a plurality of silica or Pure Silicon Metal or both mixtures are wrapped in to the feed particles 3 in carbon source 2.The mucus that binding agent and water form can be made by the aqueous solution (PVA is polyvinyl alcohol) of 5%PVA.
Therefore, the feed particles 3 in this example comprises inner silica or Pure Silicon Metal and is wrapped in the carbon source 2 outside silica or Pure Silicon Metal, includes binding liquid, timber and silicon carbide in carbon source 2.
As preferably, feed particles 3 of the present invention is as follows:
The particle diameter of silicon-dioxide: 0.01mm-1mm, is preferably 50um, and weight ratio is: the 2-4 of carbon source 2 doubly.Be preferably 3 times.
The diameter of carbon source 2 particles: 1um-100um, is preferably 50um.
The gross weight of carbon source 2 is 20-40% of silicon-dioxide, is preferably 30%, and wherein wood chip is the 4-6% of carbon source 2, is preferably 5%; Bamboo carbon is the 25-35% of whole carbon sources 2, is preferably 30%.
Ash oontent: below 1ppm; Ash content is the impurity in silicon carbide.
Bonding prevents material: silicon carbide, the 2-7% that weight is silica weight, is preferably 5%.
When carrying out a series of reaction, reaction in feed particles 3 or near carry out, atmosphere in conversion unit is oxidizing gas, so just can prevent that ash content from polluting the silicon carbide generating, and can reduce to 1/10th of original method to the pollution of product.
Embodiment 2:
According to our experiment, although the impurity containing in the silicon carbide that reaction generates is mainly derived from silicon-dioxide and carbon raw material, carbon during as heating member, also comprises carbon dioxide process carbon electrode, and the ash content in fact producing after reaction is very large on the purity impact of silicon carbide.At carbon, add in the reducing atmosphere of thermosetting, when silicon-dioxide is reduced, as the ash content of residue, also by reducing atmosphere around, to be reduced, the reduction elements diffusion wherein generating invades in the silicon carbide of generation, the silicon carbide generating is polluted, cause the purity of silicon carbide low.
In this case, the present invention includes and adopt the equipment that is equipped with plasma generator 4 to produce silicon carbide.Plasma generator 4 can generate the high temperature of 3000 degrees Celsius.Its exit end that feed particles 3 joins in the inner or inner gas duct of plasma generator 4 or plasma generator 4 outsides increase is in addition approached in the conduit of gas duct.Specifically, as shown in Figure 4, plasma generator 4 inside have the cavity 41 consisting of sleeve and communicate with gas duct 42, and gas duct 42 is for gases such as logical argon gas, thereby its outlet is divided into ion through high-voltage produces plasma flame, and it is higher that plasma flame more approaches air outlet temperature.Feed particles 3 joins from the cavity 41 of the inside of plasma generator 4 or inner gas duct 42, and then along with gravity fall is carried out reacting by heating to the air outlet of gas duct 42 by plasma thermal-flame moment.Especially, article on plasma generating unit 4 also improves in this example, at inner several conduits that increase of plasma generator 4, conduit upper end port is opened in the upper end of plasma generator 4, and the lower end that lower end is opened in plasma generator 4 communicates with gas duct 42.
Pollution for fear of the reduction of ash content and to the silicon carbide generating, must discharge ash content as early as possible or will after ash content oxidation, discharge by gas simultaneously by gas.Plasma flame is produced by more than one or one plasma generator, and plasma flame is greater than the speed ejection of 50 meter per seconds with speed.In isoionic thermal-flame, add feed particles 3, the gas and the impurity that in reduction reaction at a high speed, produce have little time just to contact and be discharged from the silicon carbide generating, and can prevent the pollution of ash content to silicon carbide.
While adopting this method to prepare silicon carbide, can adopt the equipment that plasma generator 4 is housed as follows:
As shown in Figure 5, the inside of Reaktionsofen is cavity, the isolated outside air of internal cavities of Reaktionsofen.Reaktionsofen bottom is provided with crucible 5 and lifting pin 6, and lifting pin 6 is positioned at crucible 5 bottoms, and lifting pin 6 is fixed with near the end of crucible 5 pallet 7 matching with crucible 5 bottom shapes, and crucible 5 is placed in pallet 7.Crucible 5 is for collecting the silicon carbide making, and pallet 7 is for fixing crucible 5, and lifting pin 6 can drive pallet 7 to move up and down; In taking-up, make silicon carbide time lifting pin 6 is fallen, the crucible 5 of conveniently taking away, when collecting silicon carbide, lifting pin 6 can be positioned at crucible 5 from gas duct 42 lower port a distance according to practical situation, and the silicon carbide that crucible 5 can be made is collected completely.Plasma generator 4 is one, be fixed on Reaktionsofen top, plasma generator 4 has a sleeve 43, gas duct 42 is located in sleeve 43, on sleeve 43 peripherys, there is radiator element, on plasma generator 4, be also provided with cooling line 8, cooling line 8 has cooling water inlet 81 and cooling water outlet 82.Cooling water inlet 81 is connected with a water pump, cooling-water flowing overcooling pipeline 8, and the heat that plasma generator 4 is produced is taken away, and makes plasma generator remain on safe working temperature.The arranged outside of plasma generator 4 has gas to adjust cylinder 9, and gas adjustment cylinder 9 can prevent air-flow upset plasma flame, makes feed particles can be subject to uniform heat, guarantees reacting completely of feed particles, improves the purity of the silicon carbide making.
In Reaktionsofen, be provided with by air-flow the product tripping device separated with impurity.Tripping device comprises and Reaktionsofen sidepiece lower end the inlet mouth 10 being communicated with in Reaktionsofen inner chamber and air outlet 11, inlet mouth 10 places are provided with gas blower, the bottom of Reaktionsofen is provided with the outer wall pod parallel with Reaktionsofen inwall 12, the inner air-flow that impurity is blowed to air outlet that forms of pod 12,11 places, air outlet have impurity and collect ware.During outlet in feed particles 3 by plasma generator 4, part impurity can be due to high-temperature gasification, and now silicon carbide is in solid-state; Gas blower is blown into gas identical in the internal cavities with Reaktionsofen from inlet mouth, impurity on reacted silicon carbide is taken away by air-flow, simultaneously also ash content can the be blown off surface of silicon carbide, air-flow to air outlet with impurity is located, and impurity reduces crystallization again at place, air outlet and collects on ware at impurity due to temperature.
The upper end of the sleeve 43 of plasma generator 4 is provided with four feed-pipes 44, and as shown in Figure 4, feed particles 3 enters sleeve 43 by feed-pipe to enlarged view, and the interior landing of cavity 41 between sleeve 43 and gas duct 42.When throwing raw materials particle 3, according to practical situation, can in gas duct 42, in company with gas, send into together in gas duct 42, also can in the feed-pipe from sleeve 43, drop into, outside feed particles 3 drops into sleeve 43, will enter in plasma flame, plasma flame is by producing in gas duct 42 ports, temperature progressively reduces by 12000 degrees Celsius, the silicon-dioxide of feed particles 3 or Pure Silicon Metal react Formed SiClx with carbon source 2 in plasma flame, and feed particles 3 chemical equation is at high temperature SiO
2+ 3C=SiC+2CO ↑.Plasma flame can produce blast air, the impurity that is attached to silicon carbide can be blown away; A part of impurity gasification when through plasma flame in raw material, the impurity after gasification can blow away from silicon carbide, only has the impurity of only a few to fall into Reaktionsofen, and the purity of the silicon carbide therefore making is high.
Embodiment 3:
When using plasma generator 4 to add hot preparation silicon carbide as high temperature source, the present invention has also further proposed the silicon carbide preparation method of plurality of raw materials form.
A preparation method for silicon carbide, comprises carbon source 2 and silica 1 or Pure Silicon Metal or both mixtures is directly put into and in plasma flame, carry out reacting by heating and then Formed SiClx simultaneously.Present method is that carbon source 2 and silica 1 or Pure Silicon Metal are directly put in plasma flame by passage separately simultaneously, afterwards just can Formed SiClx as long as guarantee to mix fully between the two in input.
Specifically, carbon source 2 is materials that carbon plays reduction reaction or a carburizing reagent in reacting with element silicon.Described carbon source 2 is gaseous carbon source 2, and gaseous carbon source 2 is one or several mixing in hydrocarbon, hydrocarbon polymer, fluorocarbon or carbon chlorine compound.
Described carbon source 2 is solid-state carbon source 2, and solid-state carbon source 2 is one or more mixing in graphite, pure carbon, coke, refinery coke or timber.
In reaction, according to the component of silica or Pure Silicon Metal, ensure enough carbon sources.
The method adopts the equipment that plasma generator 4 is housed as follows:
As shown in Figure 6, a kind of plasma heating device, comprise that inside is the Reaktionsofen of cavity, at least one plasma generator 4, the gas duct 42 of plasma generator 4 is positioned at the crucible 5 of Reaktionsofen, the gas duct 42 lower port places of plasma generator 4 can produce plasma flame, outside plasma generator 4, have additional some feed conduits 13, the discharge port of feed conduits 13 down, and converge and approach gas duct 42 lower port, the angle 15-45 degree of feed conduits 13 and gas duct 42.Feed conduits 13 is uniformly distributed.During use, carbon source 2, silica 1 or Pure Silicon Metal drop into by above-mentioned method steps respectively from feed conduits 13.
The isolated outside air of internal cavities of Reaktionsofen.Reaktionsofen top has the exhaust-duct 14 being connected with the cavity of Reaktionsofen, and the sidepiece of Reaktionsofen has venting channels.Between exhaust-duct 14 and Reaktionsofen, by air-flow, adjusting cylinder 15 is communicated with, the gas duct 42 of plasma generator 4 and feed conduits 13 are all positioned at air-flow and adjust cylinder 15, air-flow adjustment cylinder 15 is truncated cone-shaped, the less one end of air-flow adjustment cylinder 15 diameters is positioned at Reaktionsofen, and the larger one end of air-flow adjustment cylinder 15 diameters is positioned at exhaust-duct 14.Plasma generator 4 can produce air-flow in use, and exhaust-duct and venting channels can guide air-flow to flow out from Reaktionsofen, and can in Reaktionsofen, not produce sinuous flow; The plasma flame of plasma generator 4 ejection is subject to the protection that air-flow is adjusted cylinder, guarantees the shape of flame, makes raw material be positioned at plasma flame from feed conduits 13 out.
Embodiment 4:
For improving the purity of Formed SiClx, present method comprises a purification step.The purification step of present method is that silicon carbide is put in purification passage after surperficial washing and pickling, the thermograde that formation temperature increases continuously in purification passage, impure silicon carbide progressively gasifies respectively fusing point lower than the metallic impurity of silicon carbide through purification passage, after silicon carbide gasification, the silicon carbide of gasification is detached and forms solid-state silicon carbide.Because temperature in purification passage is Gradient distribution, impure silicon carbide first passes through the first area of thermograde, by the high temperature of 1500 degrees Celsius, the metallic impurity of silicon carbide are gasified, entered again second area, high temperature by 2800 degrees Celsius gasifies silicon carbide, the metallic impurity of silicon carbide inside also will gasify, because proportion is different, most of silicon carbide concentrates in one deck, at this moment the silicon carbide of gasification is detached and form solid-state silicon carbide, so just can mention 99.99999% silicon carbide purity.Thermograde is divided into several heating regions, and each heating region is heated by each heating unit.In heating region, be provided with the air feed port that supplied gas flows into.The inflow direction of gas is contrary with the inflow direction of silicon carbide.The obstruction flowing into by gas, silicon carbide can be suspended in this region more for a long time, thereby can extend the time of purification.At heating region, be provided with the air outlet for the gas in purification passage and/or powder outflow.In order as soon as possible gas to be discharged, the passage of exhaust must be the shortest, and in the structure of former Reaktionsofen, the distance of passage is oversize, must cause secondary pollution, and the length of air outlet is 1cm～5cm.
Shielding gas passes into the direction contrary with silicon carbide.Shielding gas is argon gas, allows feed particles 3 remain on floating state, and the impurity of evaporation is discharged from its intrinsic temperature province, finally can collect in high-temperature part the high-purity carborundum of distillation.For the amount of distillation, the effect of swimming of the gas of bottom ejection is very large, compares with the distillation amount of the effect of not swimming, and the amount of collection is its 3 times.
Use after method of purification, the content of impurity reduces to 1/4th of original content nearly.
The concrete structure of purifying plant is as follows:
A kind of heating purifying plant, comprise purified reaction stove 16, purified reaction stove 16 tops are connected with raw material supplying bucket 17, between raw material supplying bucket 17 and purified reaction stove 16, input speed setter 18 is set, input speed setter 18 is by regulating openings of sizes to control the speed that raw material enters purified reaction stove 16 inner chambers.Purified reaction stove 16 bottoms are connected with the gas feed 1 for the material of purified reaction stove 16 being swum and moving, heating purifying plant also comprises can make the interior different zones temperature of purified reaction stove 16 reach respectively the heating unit of setting numerical range, the temperature that in the present embodiment, heating unit makes a purified reaction stove 16 from top to bottom minute temperature increases progressively successively, form continuous thermograde, can be divided into two-layer, be respectively the first temperature province 19 and the second temperature province 20, on purified reaction stove 16, be provided with in temperature province 19, in 20, extract the silicon carbide collection mouth 162 of high-purity product and the impurity of derivation impurity out and collect mouth 163, purified reaction stove 16 tops are also provided with venting port 164, the metallic impurity that comprise various gasifications with all gas of discharge.Heating unit comprises graphite heating body and copper electrode, and graphite heating body covers Reaktionsofen outside surface, and copper electrode one end is connected with graphite heating body, and the other end is connected with power supply.Purified reaction stove 16 bottoms are also provided with for pass into the gas feed 2 165 of reactive gas to purified reaction stove 16.Reactive gas can be hydrogen or chlorine, and reactive gas can increase the activity of silicon-carbide particle.In purified reaction stove 16, be also provided with the gas-sparging head 21 of at least one the auxiliary use of swimming, gas-sparging head 21 is disc, on gas-sparging head 21, have some gas ejection ports, the gas-sparging head 21 of the auxiliary use of swimming is communicated with corresponding gas feed 3 166 respectively by pipeline.Gas-sparging head 21 lays respectively at the first temperature province 19 and the second temperature province 20, and the gas-sparging head 21 that is positioned at the first temperature province 19 makes silicon carbide longer in the time of the first temperature province 19, makes impurity have time enough gasification; The gas-sparging head 21 that is positioned at the second temperature province 20 can make silicon carbide major part swim in the second temperature province 20, and the auxiliary silicon carbide having gasified enters faster silicon carbide and collects mouthfuls 162 simultaneously.
Gas feed top arranges the disk that level covers purified reaction barrel cavity, and disc surfaces is evenly distributed with several gas jetting holes.The gas entering from gas feed 1 disperses after disperseing by the gas jetting hole 21 disk, increase the crystallization number of the silicon carbide of the gasification that is positioned at purified reaction stove 16 bottoms, improve the recovery rate of highly purified silicon carbide, it is more even that gas jetting hole by disk makes to spray into the gas of purified reaction bucket simultaneously, the swim effect of increase to silicon-carbide particle, slows down the speed that drops of particle.
Embodiment 5:
Voltage: direct current 120V; Electric current: 200A; Striking voltage: 20000V; Plasma gas: argon gas; Flow: 20L/ divides.
The operating condition of heating is: heating member: the heating member of carbon/carbon composite; Voltage: 55V; Electric current: 2500A; The formation in differing temps region: prepare several heating members, voltage 55V fixes, according to the control formation temperature gradient to electric current.
According to experimental result, the source of generation of clear and definite impurity is ash content, and the also clear and definite silicon carbide reactor that carries out in the atmosphere of oxidation can suppress the diffuse pollution to silicon carbide of impurity in ash content.Composition silica being contained if also clear and definite manages, and does not need special method of purification, according to production method of the present invention, can access purity and be 99.99% silicon carbide.In addition, if use feed particles 3, by high speed, react and high speed exhaust, pollute for 2 times that can significantly be reduced in technique.
Except 5 above-mentioned embodiment, can also combine embodiment 1,2,3,4, form different preparation methods.
Claims (23)
1. a preparation method for silicon carbide, is characterized in that, the method comprises that the carbon source (2) by carbon elements wraps silica (1) or Pure Silicon Metal or both mixtures completely and makes feed particles (3); Feed particles (3) is at high temperature reacted to Formed SiClx.
2. the preparation method of silicon carbide according to claim 1, is characterized in that, described carbon source (2) is solid-state, is the material that carbon plays reduction reaction or a carburizing reagent in reacting with element silicon.
3. the preparation method of silicon carbide according to claim 2, is characterized in that, described carbon source (2) is one or more mixing in graphite, wooden carbon, coke, refinery coke or powder timber.
4. the preparation method of silicon carbide according to claim 1 and 2, is characterized in that, the maximum diagonal of described feed particles (3) or maximum diameter are 0.001mm～5mm.
5. the preparation method of silicon carbide according to claim 3, is characterized in that, described feed particles (3) is that single silica (1) or single metal silicon are wrapped in the feed particles (3) in carbon source (2); Or described feed particles (3) is integrated into a whole feed particles (3) for several individual particles, and individual particle refers to that single silica (1) or single metal silicon are wrapped in carbon source (2).
6. the preparation method of silicon carbide according to claim 5; it is characterized in that; after described carbon source (2), silica (1) or Pure Silicon Metal or both mixtures mix; add again binding agent and water to stir and dry, by tablets press, form and a plurality of silica (1) or Pure Silicon Metal or both mixtures are wrapped in to the feed particles (3) in carbon source (2).
7. the preparation method of silicon carbide according to claim 5, it is characterized in that, in carbon source (2), add binding agent and water to stir to form mucus, the single silica (1) of monolayer alignment or Pure Silicon Metal are immersed in this mucus or directly by mucus, by spraying method, form single silica (1) or Pure Silicon Metal or both mixtures be wrapped in the feed particles (3) in carbon source (2).
8. the preparation method of silicon carbide according to claim 5, is characterized in that, the silicon carbide that it is 0.5-10% that described feed particles (3) also comprises containing weight percent.
9. the preparation method of silicon carbide according to claim 8, is characterized in that, the element silicon in described feed particles (3) and the mass ratio of carbon are 3:1～3:3.
10. a preparation method for silicon carbide, is characterized in that, the method comprises and adopts the equipment be equipped with plasma generator (4) to produce silicon carbide.
The preparation method of 11. silicon carbide according to claim 10, it is characterized in that, feed particles (3) joins in plasma generator (4) inner (41) or inner gas duct (42) or outside its exit end increasing in addition of plasma generator (4) approaches in the conduit (13) of gas duct (42).
The preparation method of 12. 1 kinds of silicon carbide, is characterized in that, comprises carbon source (2) and silica (1) or Pure Silicon Metal or both mixtures directly put in the plasma flame that generating unit produces and carry out reacting by heating simultaneously, and then Formed SiClx.
The preparation method of 13. silicon carbide according to claim 12, is characterized in that, carbon source (2) is the material that carbon plays reduction reaction or a carburizing reagent in reacting with element silicon.
The preparation method of 14. silicon carbide according to claim 13, it is characterized in that, described carbon source (2) is gaseous carbon source (2), and gaseous carbon source (2) is one or several mixing in hydrocarbon, hydrocarbon polymer, fluorocarbon or carbon chlorine compound.
The preparation method of 15. silicon carbide according to claim 13, is characterized in that, described carbon source (2) is solid-state carbon source (2), and solid-state carbon source (2) is one or more mixing in graphite, pure carbon, coke, refinery coke or timber.
The preparation method of 16. silicon carbide according to claim 13, it is characterized in that, carbon source (2) and silica (1) or Pure Silicon Metal or both mixtures are made to the feed particles (3) described in the claims 1-9 and directly put into and in plasma flame, carry out reacting by heating.
The preparation method of 17. silicon carbide according to claim 12, is characterized in that, described plasma flame is by one or above plasma generator (4) generation.
18. according to the preparation method of silicon carbide described in claim 10-17 any one, it is characterized in that, plasma flame is greater than the speed ejection of 50 meter per seconds with speed.
The preparation method of 19. 1 kinds of silicon carbide, it is characterized in that, present method comprises a purification step, the thermograde that formation temperature increases continuously in purification passage, the silicon carbide of interior metal impurities progressively gasifies respectively boiling point lower than the metallic impurity of silicon carbide crystallization boiling point through purification passage, after silicon carbide gasification, the silicon carbide of gasification is detached and forms solid-state silicon carbide.
The preparation method of 20. silicon carbide according to claim 19, is characterized in that, described thermograde is divided into several heating regions.
The preparation method of 21. silicon carbide according to claim 20, is characterized in that, is provided with the air feed port that supplied gas flows in heating region.
The preparation method of 22. silicon carbide according to claim 20, is characterized in that, at heating region, is provided with the air outlet for the gas in purification passage and/or powder outflow.
The preparation method of 23. silicon carbide according to claim 20, is characterized in that, the air outlet length of extracting out for silicon carbide is 1cm～15cm.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201310477645.XA CN103539122B (en) | 2013-10-12 | 2013-10-12 | A kind of preparation method of silicon carbide |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201310477645.XA CN103539122B (en) | 2013-10-12 | 2013-10-12 | A kind of preparation method of silicon carbide |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN103539122A true CN103539122A (en) | 2014-01-29 |
| CN103539122B CN103539122B (en) | 2015-12-02 |
Family
ID=49963045
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201310477645.XA Expired - Fee Related CN103539122B (en) | 2013-10-12 | 2013-10-12 | A kind of preparation method of silicon carbide |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN103539122B (en) |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108467035A (en) * | 2018-02-11 | 2018-08-31 | 安徽海德化工科技有限公司 | The preparation method of carbon molecular sieve based on petroleum coke |
| WO2020103280A1 (en) * | 2018-11-23 | 2020-05-28 | 山东天岳先进材料科技有限公司 | High-purity silicon carbide powder and preparation method therefor |
| CN111663184A (en) * | 2020-06-23 | 2020-09-15 | 柯良节 | Novel plasma sublimation crystallization furnace and preparation method of silicon carbide crystal rod |
| CN113716567A (en) * | 2021-09-30 | 2021-11-30 | 中国航发北京航空材料研究院 | Preparation method of silicon carbide nanotube based on direct current pulse excitation |
| CN114318290A (en) * | 2022-01-05 | 2022-04-12 | 巩义市泛锐熠辉复合材料有限公司 | Method and device for preparing focusing ring for semiconductor equipment |
Citations (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS63147812A (en) * | 1986-12-10 | 1988-06-20 | Nippon Sheet Glass Co Ltd | Production of silicon carbide powder |
| JPH01172205A (en) * | 1987-12-26 | 1989-07-07 | Ibiden Co Ltd | Raw material composition for producing metal carbide |
| WO1990010595A1 (en) * | 1989-03-16 | 1990-09-20 | Davy Research And Development Limited | Process |
| KR20010075561A (en) * | 1998-10-01 | 2001-08-09 | 조셉 제이. 스위니 | In situ deposition of low k si carbide barrier layer, etch stop, and anti-reflective coating for damascene applications |
| CN101254919A (en) * | 2008-04-07 | 2008-09-03 | 河南醒狮高新技术股份有限公司 | In-situ synthesis of high-pure green 6H-SiC |
| CN101434391A (en) * | 2007-11-14 | 2009-05-20 | 贾玉东 | Method for smelting green silicon carbide abrasive material |
| WO2010027545A2 (en) * | 2008-09-03 | 2010-03-11 | Ppg Industries Ohio, Inc. | Methods for the production of ultrafine metal carbide particles and hydrogen |
| JP2011042571A (en) * | 2010-10-04 | 2011-03-03 | National Institute For Materials Science | Manufacturing method for sic nanoparticle by nitrogen plasma |
| CN102123944A (en) * | 2008-08-19 | 2011-07-13 | 赢创德固赛有限公司 | Production of silicon by reacting silicon oxide and silicon carbide, optionally in the presence of a second carbon source |
| CN102491330A (en) * | 2011-11-14 | 2012-06-13 | 朱胜利 | Production process of silicon carbide |
| KR20120121109A (en) * | 2011-04-26 | 2012-11-05 | (주)네오플랜트 | Production method for nano-sized silicone carbide using thermal plasma |
-
2013
- 2013-10-12 CN CN201310477645.XA patent/CN103539122B/en not_active Expired - Fee Related
Patent Citations (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS63147812A (en) * | 1986-12-10 | 1988-06-20 | Nippon Sheet Glass Co Ltd | Production of silicon carbide powder |
| JPH01172205A (en) * | 1987-12-26 | 1989-07-07 | Ibiden Co Ltd | Raw material composition for producing metal carbide |
| WO1990010595A1 (en) * | 1989-03-16 | 1990-09-20 | Davy Research And Development Limited | Process |
| KR20010075561A (en) * | 1998-10-01 | 2001-08-09 | 조셉 제이. 스위니 | In situ deposition of low k si carbide barrier layer, etch stop, and anti-reflective coating for damascene applications |
| CN101434391A (en) * | 2007-11-14 | 2009-05-20 | 贾玉东 | Method for smelting green silicon carbide abrasive material |
| CN101254919A (en) * | 2008-04-07 | 2008-09-03 | 河南醒狮高新技术股份有限公司 | In-situ synthesis of high-pure green 6H-SiC |
| CN102123944A (en) * | 2008-08-19 | 2011-07-13 | 赢创德固赛有限公司 | Production of silicon by reacting silicon oxide and silicon carbide, optionally in the presence of a second carbon source |
| WO2010027545A2 (en) * | 2008-09-03 | 2010-03-11 | Ppg Industries Ohio, Inc. | Methods for the production of ultrafine metal carbide particles and hydrogen |
| JP2011042571A (en) * | 2010-10-04 | 2011-03-03 | National Institute For Materials Science | Manufacturing method for sic nanoparticle by nitrogen plasma |
| KR20120121109A (en) * | 2011-04-26 | 2012-11-05 | (주)네오플랜트 | Production method for nano-sized silicone carbide using thermal plasma |
| CN102491330A (en) * | 2011-11-14 | 2012-06-13 | 朱胜利 | Production process of silicon carbide |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108467035A (en) * | 2018-02-11 | 2018-08-31 | 安徽海德化工科技有限公司 | The preparation method of carbon molecular sieve based on petroleum coke |
| WO2020103280A1 (en) * | 2018-11-23 | 2020-05-28 | 山东天岳先进材料科技有限公司 | High-purity silicon carbide powder and preparation method therefor |
| CN111663184A (en) * | 2020-06-23 | 2020-09-15 | 柯良节 | Novel plasma sublimation crystallization furnace and preparation method of silicon carbide crystal rod |
| CN113716567A (en) * | 2021-09-30 | 2021-11-30 | 中国航发北京航空材料研究院 | Preparation method of silicon carbide nanotube based on direct current pulse excitation |
| CN113716567B (en) * | 2021-09-30 | 2023-08-04 | 中国航发北京航空材料研究院 | Preparation method of silicon carbide nanotubes based on direct current pulse excitation |
| CN114318290A (en) * | 2022-01-05 | 2022-04-12 | 巩义市泛锐熠辉复合材料有限公司 | Method and device for preparing focusing ring for semiconductor equipment |
Also Published As
| Publication number | Publication date |
|---|---|
| CN103539122B (en) | 2015-12-02 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN103539122B (en) | A kind of preparation method of silicon carbide | |
| US8747524B2 (en) | Method and equipment for separating out molten dust in high temperature gas and use thereof | |
| WO2015131755A1 (en) | Method for preparing silicon carbide | |
| KR20100087603A (en) | Continuous process for preparing fine particulate zinc oxide, and the apparatus therefor | |
| CN1974383B (en) | Production process for high purity polycrystal silicon and production apparatus for the same | |
| CN101723387A (en) | Method and device for producing high purity quartz sand | |
| CN201512418U (en) | Polycrystalline silicon reducing furnace | |
| US20120251427A1 (en) | Reactor and method for production of silicon | |
| CN102994160B (en) | Entrained-flow bed gasifier for solid-phase deslagging | |
| CN202898362U (en) | Partially chilled dry pulverized coal or coal water slurry gasification system | |
| CN103160328A (en) | Coal dry powder gasification device | |
| CN106219488B (en) | A kind of method and device preparing hydrochloric acid and purifying quartz sand | |
| US2201738A (en) | Process for effecting reducing metallurgical reactions | |
| CN102012160A (en) | Smelting furnace | |
| CN206033688U (en) | Powdered coal gasification equipment | |
| CN205472696U (en) | Calcium carbide furnace | |
| CN107460340A (en) | A kind of quick blow-in method of copper bottom-blown smelting stove | |
| CN201470881U (en) | Submicron zinc powder preparation plant | |
| CN106637137A (en) | High-efficiency and energy-saving zinc selenide vapor deposition furnace | |
| CN102331169A (en) | Smelting furnace | |
| US2761767A (en) | Apparatus for the manufacture of red lead | |
| CN206590908U (en) | A kind of oxidizing process continuously prepares Nano-meter SiO_22Device | |
| CN102259859A (en) | Production technology for metallurgical silicon with low boron content and low phosphorus content | |
| CN202182611U (en) | Smelting furnace | |
| KR100985676B1 (en) | zinc oxide powder manufacturing apparatus and method |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| TR01 | Transfer of patent right | ||
| TR01 | Transfer of patent right |
Effective date of registration: 20200107 Address after: West of 4th floor, building 3, No. 818, east section of development avenue, Taizhou City, Zhejiang Province Patentee after: TAIZHOU BEYOND TECHNOLOGY Co.,Ltd. Address before: 318000, Zhejiang, Taizhou Province, 818 Eastern Road Development Avenue, 3, west side of the 4 Co-patentee before: Hoshino Masahiro Patentee before: TAIZHOU BEYOND TECHNOLOGY Co.,Ltd. |
|
| CF01 | Termination of patent right due to non-payment of annual fee | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20151202 Termination date: 20211012 |