CN105417546A - Cleaning fluid used for polycrystalline silicon material and cleaning process of polycrystalline silicon material - Google Patents
Cleaning fluid used for polycrystalline silicon material and cleaning process of polycrystalline silicon material Download PDFInfo
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- CN105417546A CN105417546A CN201510761871.XA CN201510761871A CN105417546A CN 105417546 A CN105417546 A CN 105417546A CN 201510761871 A CN201510761871 A CN 201510761871A CN 105417546 A CN105417546 A CN 105417546A
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- silicon material
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- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B33/00—Silicon; Compounds thereof
- C01B33/02—Silicon
- C01B33/037—Purification
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- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2006/00—Physical properties of inorganic compounds
- C01P2006/40—Electric properties
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Abstract
The invention provides cleaning fluid used for cleaning a polycrystalline silicon material. The cleaning fluid comprises hydrofluoric acid and hydrogen peroxide. According to the cleaning fluid used for the polycrystalline silicon material and a cleaning process of the polycrystalline silicon material, the silicon material to be cleaned is directly soaked in the cleaning fluid, the situation that the silicon material with mortar and the silicon material without mortar in a tail red area are cut off and separated to be cleaned is avoided, and the loss of the silicon material is reduced; besides, the silicon material cleaning process is simple, the obtained silicon material can directly serve as a recycling material to be fed into a furnace for use, melted production of the silicon material is omitted, and the energy loss in the ingot casting melted process is reduced.
Description
Technical field
The invention belongs to field of polysilicon technology, be specifically related to the cleaning of a kind of scavenging solution for polycrystalline silicon material and a kind of polycrystalline silicon material.
Background technology
Current crystal silicon solar energy battery is in occupation of the dominant position of photovoltaic industry.And the cost of silicon chip has accounted for the over half of list/polycrystalline silicon cost, therefore reduce the cost of silicon chip, improve the quality of silicon chip, the development for photovoltaic industry has extremely important meaning, by the silicon ingot of half process of smelting ingot casting, Si wafer quality and preparation efficiency are all better.
When being adopted half process of smelting growth casting polycrystalline crystal by ingot furnace, need bottom quartz crucible, to place fine particle material as seed crystal.Need to control bottom seed crystal in the unmelted polycrystalline silicon stage non-fusible, but in the evolution stage, mortar can invade the inside of these infusible bottom seed portion, mortar is full of void layer, and the mortar of this part uses pickling to remove, separate cleaning so afterbody red sector must be had mortar in truncated process and block without the silicon material of mortar, which increase the loss of silicon material, cut the silicon material of a cutter loss 3mm.Can reuse as reclaimed materials do not have the silicon material pickling of mortar after having cut after, but have the silicon material of mortar to need to be polished by bottom, sorting, breaks into pieces, just can melt down after a series of activities such as pickling, complex treatment process, and energy consumption is higher.
Summary of the invention
In view of this, the technical problem to be solved in the present invention is the cleaning providing a kind of scavenging solution for polycrystalline silicon material and a kind of polycrystalline silicon material, the scavenging solution of polycrystalline silicon material provided by the invention may be used for the cleaning of polycrystalline silicon material, cleaning is simple, energy consumption is low, and can reduce the loss of silicon material.
The invention provides a kind of scavenging solution for cleaning polycrystalline silicon material, comprising: hydrofluoric acid and hydrogen peroxide.
Preferably, in described scavenging solution, the mass concentration of hydrofluoric acid is 1wt% ~ 10wt%, and the mass concentration of hydrogen peroxide is 2wt% ~ 25wt%.
Present invention also offers a kind of cleaning of polycrystalline silicon material, comprise the following steps:
After the scavenging solution be placed in by silicon material to be cleaned for cleaning polycrystalline silicon material soaks, through overpickling, washing and drying, obtain the polycrystalline silicon material cleaned up, described scavenging solution comprises hydrofluoric acid and hydrogen peroxide.
Preferably, in described scavenging solution, the mass concentration of hydrofluoric acid is 1wt% ~ 10wt%, and the mass concentration of hydrogen peroxide is 2wt% ~ 25wt%.
Preferably, the time of described immersion is 6 ~ 20 hours, and the temperature of immersion is 20 ~ 60 DEG C.
Preferably, the acid solution of described pickling is the mixing acid of nitric acid and hydrofluoric acid.
Preferably, the mass concentration of described nitric acid is 40wt% ~ 70wt%, and the mass concentration of described hydrofluoric acid is 40wt% ~ 60wt%.
Preferably, the volume ratio of described nitric acid and hydrofluoric acid is 1:5 ~ 1:10.
Preferably, the time of described pickling is 20 ~ 40s, and the temperature of described pickling is 60 ~ 100 DEG C.
Preferably, described washing adopts ultrasonic wave water washing.
Compared with prior art, the invention provides a kind of scavenging solution for cleaning polycrystalline silicon material, comprising: hydrofluoric acid and hydrogen peroxide.Silicon material to be cleaned is directly soaked in scavenging solution by the present invention, just afterbody red sector can be avoided to have mortar and block without the silicon material of mortar separating cleaning, decrease the loss of silicon material, and silicon material cleaning is simple, the silicon material obtained directly can be thrown stove as cycle stock and use, that exempts silicon material melts down production, and saving ingot casting melts down the energy loss in process.
Result shows, the polycrystalline silicon material surface after cleaning is without dirty; And inhale silicon material, without metal sucking-off with metal detection rod; The resistivity measuring described polycrystalline silicon material is 1 ~ 3 Ω m.
Embodiment
The invention provides a kind of scavenging solution for cleaning polycrystalline silicon material, comprising: hydrofluoric acid and hydrogen peroxide.
Scavenging solution provided by the invention is the mixed aqueous solution of hydrofluoric acid and hydrogen peroxide, and wherein, when carrying out mixed aqueous solution configuration, solvent is preferably pure water.
In described scavenging solution, the mass concentration of hydrofluoric acid is 1wt% ~ 10wt%, is preferably 2wt% ~ 8wt%; In some embodiments of the invention, the mass concentration of described hydrofluoric acid is 1wt%; In other embodiments of the present invention, the mass concentration of described hydrofluoric acid is 4wt%; In other embodiments of the present invention, the concentration of described hydrofluoric acid is 10wt%.In described scavenging solution, the mass concentration of hydrogen peroxide is 2wt% ~ 25wt%, is preferably 5wt% ~ 20wt%; In some embodiments of the invention, the mass concentration of described hydrogen peroxide is 2wt%; In other embodiments of the present invention, the mass concentration of described hydrogen peroxide is 12wt%; In other embodiments of the present invention, the mass concentration of described hydrogen peroxide is 25wt%.
Scavenging solution provided by the invention is for cleaning polycrystalline silicon material, and wherein, the kind of the present invention to described polycrystalline silicon material does not have particular restriction, is preferably the silicon material with mortar.
Present invention also offers a kind of cleaning of polycrystalline silicon material, comprise the following steps:
After the scavenging solution be placed in by silicon material to be cleaned for cleaning polycrystalline silicon material soaks, through overpickling, washing and drying, obtain the polycrystalline silicon material cleaned up, described scavenging solution comprises hydrofluoric acid and hydrogen peroxide.
Silicon material to be cleaned of the present invention is preferably the silicon material with mortar, is more preferably the silicon material of the bottom red sector after silicon ingot infra-red inspection.
After the silicon material of the bottom red sector after silicon ingot infra-red inspection blocks by the present invention, and before soaking in scavenging solution, preferably bottom red sector layer is polished, to remove the residual glue of bottom butt.The method of the present invention to polishing does not have particular restriction, well known to a person skilled in the art polishing process.
After bottom red sector layer polishing after silicon ingot infra-red inspection terminates, described silicon material to be cleaned is placed in scavenging solution and soaks.In the present invention, described scavenging solution is the mixed aqueous solution of hydrofluoric acid and hydrogen peroxide, and wherein, when carrying out mixed aqueous solution configuration, solvent is preferably pure water.
In described scavenging solution, the mass concentration of hydrofluoric acid is 1wt% ~ 10wt%, is preferably 2wt% ~ 8wt%; In some embodiments of the invention, the mass concentration of described hydrofluoric acid is 1wt%; In other embodiments of the present invention, the mass concentration of described hydrofluoric acid is 4wt%; In other embodiments of the present invention, the concentration of described hydrofluoric acid is 10wt%.In described scavenging solution, the mass concentration of hydrogen peroxide is 2wt% ~ 25wt%, is preferably 5wt% ~ 20wt%; In some embodiments of the invention, the mass concentration of described hydrogen peroxide is 2wt%; In other embodiments of the present invention, the mass concentration of described hydrogen peroxide is 12wt%; In other embodiments of the present invention, the mass concentration of described hydrogen peroxide is 25wt%.
The time of described immersion is 6 ~ 20 hours, is preferably 8 ~ 15 hours; In some embodiments of the invention, described soak time is 6h, and in other embodiments of the present invention, described soak time is 12 hours; In other embodiments of the present invention, described soak time is 20 hours.The temperature of described immersion is 20 ~ 60 DEG C, is preferably 30 ~ 50 DEG C; In some embodiments of the invention, described soak time is 20 DEG C; In other embodiments of the present invention, described soak time is 40 DEG C; In other embodiments of the present invention, described soak time is 60 DEG C.
After immersion terminates, by the silicon material after described immersion successively through overpickling, washing and drying, obtain the polycrystalline silicon material cleaned up.
The method of the present invention to the pickling of described silicon material, washing and drying does not have particular restriction, well known to a person skilled in the art the method for the pickling of silicon material, washing and drying.
In the present invention, the pickling of described silicon material is preferably carried out as follows:
Silicon material after described immersion is placed in acid solution and carries out pickling, described acid solution is the mixing acid of nitric acid and hydrofluoric acid.
The collocation method of the present invention to described mixing acid does not have particular restriction, is mixed by nitric acid with hydrofluoric acid.Wherein, the mass concentration of described nitric acid is 40wt% ~ 70wt%, is preferably 60wt%.The mass concentration of described hydrofluoric acid is 40wt% ~ 60wt%, is preferably 48wt%.The volume ratio of described nitric acid and hydrofluoric acid is 1:5 ~ 1:10, is preferably 1:8.
The time of described pickling is 20 ~ 40s, is preferably 30s.The temperature of described pickling is 60 ~ 100 DEG C, is preferably 80 DEG C.
After pickling terminates, described silicon material is washed.In the present invention, preferably adopt at ultrasonic wave water washing.Described cleaning solvent is preferably ultrapure water.The time of described cleaning is 30 ~ 50min, is preferably 40min; Ultrasonic cleaning acc power is 21000 ~ 29000Hz, is preferably 25000Hz.
After cleaning terminates, described silicon material is dry, and the temperature of described drying is 80 ~ 120 DEG C, is preferably 100 DEG C.The time of described drying is 1 ~ 2.5h, is preferably 1.5h, finally obtains the polycrystalline silicon material cleaned up.
The present invention carries out oxidizing reaction by the weak oxide of hydrogen peroxide to the mortar remaining in silicon material surface, and carries out departing from from the surface of silicon material under the acidic conditions that mortar is provided at hydrofluoric acid thus reach the object removing mortar.After having soaked, the surface of mixing acid to silicon material of recycling hydrofluoric acid and nitric acid processes, and the silicon material of immersion is carried out ultrasonic cleaning oven dry again and add inspection after pickling, namely can be used as cycle stock throwing stove use by the silicon material of inspection.
Silicon material to be cleaned is directly soaked in scavenging solution by the present invention, just afterbody red sector can be avoided to have mortar and block without the silicon material of mortar separating cleaning, decrease the loss of silicon material, and silicon material cleaning is simple, the silicon material obtained directly can be thrown stove as cycle stock and use, that exempts silicon material melts down production, and saving ingot casting melts down the energy loss in process.
In order to understand the present invention further, be described for the scavenging solution of polycrystalline silicon material and the cleaning of polycrystalline silicon material provided by the invention below in conjunction with embodiment, protection scope of the present invention is not limited by the following examples.
Embodiment 1
After the silicon material of the bottom red sector after silicon ingot infra-red inspection is blocked, red sector layer bottom this block is first polished and removes the residual glue of bottom butt, then silicon material is put into the reaction vessel (by having the one side of mortar upwards) filling scavenging solution, wherein, in described scavenging solution, the mass concentration of hydrogen peroxide is 2wt%, the mass concentration of hydrofluoric acid is 1wt%, soak time 20h, and soaking temperature is 60 DEG C.
After immersion terminates, carry out pickling after being taken out described silicon material, described spent pickling acid is the mixing acid of hydrofluoric acid and nitric acid, wherein, is that 1:8 carries out being mixed to get mixing acid by the hydrofluoric acid of 60wt% and the nitric acid of 48wt% according to volume ratio.The time of pickling is 30s, and the temperature of pickling is 80 DEG C.
After pickling terminates, taken out by described silicon material, carry out ultrasonic cleaning, solvent for cleaning is ultrapure water, and scavenging period is 40min, and ultrasonic cleaning agent power is 25000Hz.
After cleaning terminates, described silicon material is dry, dry temperature is 90 DEG C, and the dry time is 1.5h, finally obtains the polycrystalline silicon material cleaned up.
Detect described polycrystalline silicon material, result is: surface is without dirty; And inhale silicon material, without metal sucking-off with metal detection rod; The resistivity measuring described polycrystalline silicon material is 1 ~ 3 Ω m.
Embodiment 2
After the silicon material of the bottom red sector after silicon ingot infra-red inspection is blocked, red sector layer bottom this block is first polished and removes the residual glue of bottom butt, then these silicon material are put into the reaction vessel (by having the one side of mortar upwards) filling scavenging solution, wherein, in described scavenging solution, the mass concentration of hydrogen peroxide is 12wt%, the mass concentration of hydrofluoric acid is 4wt%, soak time 12h, and soaking temperature is 40 DEG C.
After immersion terminates, carry out pickling after being taken out described silicon material, described spent pickling acid is the mixing acid of hydrofluoric acid and nitric acid, wherein, is that 1:8 carries out being mixed to get mixing acid by the hydrofluoric acid of 60wt% and the nitric acid of 48wt% according to volume ratio.The time of pickling is 30s, and the temperature of pickling is 80 DEG C.
After pickling terminates, taken out by described silicon material, carry out ultrasonic cleaning, solvent for cleaning is ultrapure water, and scavenging period is 40min, and ultrasonic cleaning agent power is 25000Hz.
After cleaning terminates, described silicon material is dry, dry temperature is 90 DEG C, and the dry time is 1.5h, finally obtains the polycrystalline silicon material cleaned up.
Detect described polycrystalline silicon material, result is: surface is without dirty; And inhale silicon material, without metal sucking-off with metal detection rod; The resistivity measuring described polycrystalline silicon material is 1 ~ 3 Ω m.
Embodiment 3
After the silicon material of the bottom red sector after silicon ingot infra-red inspection is blocked, red sector layer bottom this block is first polished and removes the residual glue of bottom butt, then these silicon material are put into the reaction vessel (by having the one side of mortar upwards) filling scavenging solution, wherein, in described scavenging solution, the mass concentration of hydrogen peroxide is 25wt%, the mass concentration of hydrofluoric acid is 10wt%, soak time 6h, and soaking temperature is 20 DEG C.
After immersion terminates, carry out pickling after being taken out described silicon material, described spent pickling acid is the mixing acid of hydrofluoric acid and nitric acid, wherein, is that 1:8 carries out being mixed to get mixing acid by the hydrofluoric acid of 60wt% and the nitric acid of 48wt% according to volume ratio.The time of pickling is 30s, and the temperature of pickling is 80 DEG C.
After pickling terminates, taken out by described silicon material, carry out ultrasonic cleaning, solvent for cleaning is ultrapure water, and scavenging period is 40min, and ultrasonic cleaning agent power is 25000Hz.
After cleaning terminates, described silicon material is dry, dry temperature is 90 DEG C, and the dry time is 1.5h, finally obtains the polycrystalline silicon material cleaned up.
Detect described polycrystalline silicon material, result is: surface is without dirty; And inhale silicon material, without metal sucking-off with metal detection rod; The resistivity measuring described polycrystalline silicon material is 1 ~ 3 Ω m.
The above is only the preferred embodiment of the present invention; it should be pointed out that for those skilled in the art, under the premise without departing from the principles of the invention; can also make some improvements and modifications, these improvements and modifications also should be considered as protection scope of the present invention.
Claims (10)
1. for cleaning a scavenging solution for polycrystalline silicon material, it is characterized in that, comprising: hydrofluoric acid and hydrogen peroxide.
2. scavenging solution according to claim 1, is characterized in that, in described scavenging solution, the mass concentration of hydrofluoric acid is 1wt% ~ 10wt%, and the mass concentration of hydrogen peroxide is 2wt% ~ 25wt%.
3. a cleaning for polycrystalline silicon material, is characterized in that, comprises the following steps:
After the scavenging solution be placed in by silicon material to be cleaned for cleaning polycrystalline silicon material soaks, through overpickling, washing and drying, obtain the polycrystalline silicon material cleaned up, described scavenging solution comprises hydrofluoric acid and hydrogen peroxide.
4. cleaning according to claim 3, is characterized in that, in described scavenging solution, the mass concentration of hydrofluoric acid is 1wt% ~ 10wt%, and the mass concentration of hydrogen peroxide is 2wt% ~ 25wt%.
5. cleaning according to claim 3, is characterized in that, the time of described immersion is 6 ~ 20 hours, and the temperature of immersion is 20 ~ 60 DEG C.
6. cleaning according to claim 3, is characterized in that, the acid solution of described pickling is the mixing acid of nitric acid and hydrofluoric acid.
7. cleaning according to claim 6, is characterized in that, the mass concentration of described nitric acid is 40wt% ~ 70wt%, and the mass concentration of described hydrofluoric acid is 40wt% ~ 60wt%.
8. cleaning according to claim 7, is characterized in that, the volume ratio of described nitric acid and hydrofluoric acid is 1:5 ~ 1:10.
9. cleaning according to claim 3, is characterized in that, the time of described pickling is 20 ~ 40s, and the temperature of described pickling is 60 ~ 100 DEG C.
10. cleaning according to claim 3, is characterized in that, described washing adopts ultrasonic wave water washing.
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| Application Number | Priority Date | Filing Date | Title |
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| CN201510761871.XA CN105417546A (en) | 2015-11-10 | 2015-11-10 | Cleaning fluid used for polycrystalline silicon material and cleaning process of polycrystalline silicon material |
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| Application Number | Priority Date | Filing Date | Title |
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| CN201510761871.XA CN105417546A (en) | 2015-11-10 | 2015-11-10 | Cleaning fluid used for polycrystalline silicon material and cleaning process of polycrystalline silicon material |
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| CN105417546A true CN105417546A (en) | 2016-03-23 |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106115715A (en) * | 2016-06-26 | 2016-11-16 | 河南盛达光伏科技有限公司 | Polycrystalline silicon ingot casting partly melts the circulation tailing cleaning treatment method that technique produces |
| CN108847401A (en) * | 2018-07-12 | 2018-11-20 | 安徽日能中天半导体发展有限公司 | A kind of cleaning method of virgin polycrystalline silicon material |
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| CN101113029A (en) * | 2006-07-26 | 2008-01-30 | 金柏林 | Treatment recovery method for monocrystalline silicon cutting waste liquor |
| CN102502652A (en) * | 2011-11-07 | 2012-06-20 | 江西旭阳雷迪高科技股份有限公司 | Cleaning process for polycrystalline material |
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- 2015-11-10 CN CN201510761871.XA patent/CN105417546A/en active Pending
Patent Citations (2)
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| CN101113029A (en) * | 2006-07-26 | 2008-01-30 | 金柏林 | Treatment recovery method for monocrystalline silicon cutting waste liquor |
| CN102502652A (en) * | 2011-11-07 | 2012-06-20 | 江西旭阳雷迪高科技股份有限公司 | Cleaning process for polycrystalline material |
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106115715A (en) * | 2016-06-26 | 2016-11-16 | 河南盛达光伏科技有限公司 | Polycrystalline silicon ingot casting partly melts the circulation tailing cleaning treatment method that technique produces |
| CN108847401A (en) * | 2018-07-12 | 2018-11-20 | 安徽日能中天半导体发展有限公司 | A kind of cleaning method of virgin polycrystalline silicon material |
| CN108847401B (en) * | 2018-07-12 | 2020-12-08 | 安徽强钢钢化玻璃股份有限公司 | Method for cleaning primary polycrystalline silicon material |
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