The making herbs into wool pretreatment fluid of a kind of diamond wire cutting polysilicon chip, making herbs into wool pretreatment process and making herbs into wool pre-treatment silicon chip and application thereof
Technical field
The invention belongs to polycrystalline silicon texturing technical field, be specifically related to the making herbs into wool pretreatment fluid of a kind of diamond wire cutting polysilicon chip, making herbs into wool pretreatment process and making herbs into wool pre-treatment silicon chip and application thereof.
Background technology
Silicon wafer is widely used in photovoltaic solar, liquid-crystal display and semiconductor applications, and the technology therefore adopting cutting silico briquette to obtain silicon chip is also developed.The cutting of current photovoltaic industry crystal silicon chip used mainly adopts mortar multi-wire saw technology, but the problem such as this technology exists that cutting technique inefficiency, cost are high, the exhaust emission of waste mortar is large after cutting.By contrast, solid abrasive diamond fretsaw cutting (being called for short diamond wire cutting) technology has the features such as cutting speed in feet per minute is fast, cutting accuracy is high, spillage of material is low, silicon chip tooling cost is low, clean environment, receives increasing concern.
In manufacture of solar cells process, silicon chip surface making herbs into wool is one critical process.Mostly current polysilicon chip is to adopt sour making herbs into wool, and it utilizes the affected layer of silicon chip surface to carry out isotropic etch, forms rugged surface, reduces silicon chip surface reflectivity, thus improves solar cell photoelectric transformation efficiency.
The surface damage layer of the polysilicon chip of conventional slurry cutting is comparatively even, is about 10-11 μm, surperficial without obvious stria (as shown in Figure 1), through RENA technique leather producing process, i.e. and HF-HNO
3-H
2o acid making herbs into wool, can obtain whole the uniform matte of corrosion (as shown in Figure 2); But the surface damage layer of diamond wire cutting polysilicon chip is more shallow, is about 5 ~ 6 μm, and its damage damages based on part small deep hole, the densely covered smooth cutting stria (as shown in Figure 3) in surface; If by the RENA leather producing process of normal polysilicon chip, the matte formed is very irregular and more shallow, be also shown in obvious stria texture (as shown in Figure 4), reflectivity is much higher than normal silicon wafer horizontal, its cell conversion efficiency is also lower, makes this novel cutting technique silicon chip cannot scale operation.
Therefore, be necessary to develop the leather producing process that can match with diamond cutting polysilicon chip, further battery production process can be carried out according to current existing operation.
In prior art; porous silicon is prepared in the chemical corrosion of metal auxiliary catalysis; normally carry out in two steps; first on silicon chip, adopt the method such as magnetron sputtering method, thermal evaporation heavy deposition metallic particles or metal film layer; then silicon chip is placed in the mixing solutions of hydrofluoric acid and oxygenant and corrodes; but porous silicon proceed step by step is prepared in corrosion, operates more loaded down with trivial details.
And the present invention is in step (a), a single metal Assisted Chemical Etching Process technology is adopted to prepare the silicon chip of vesicular structure, without the need to first preparing metallic particles.Namely silicon under the booster action of the metal ions such as silver, copper at HF/H
2o
2carry out chemical reaction in system, reaction process by the impact of the factors such as silicon chip surface degree of impairment, therefore can not form Porous Silicon structures at silicon chip surface, obtain preliminary chemical damage layer.
In the method, metallics has katalysis, and the generation of catalysis is that silicon face local exists electrochemical reaction, wherein H
2o
2negative electrode is made, H with part metals ion
2o
2+ 2H
++ 2e
-→ 2H
2o, metal ion becomes metal simple-substance particle simultaneously; And the silicon exposed is as anode, the ion of oxidisability can be assembled at the metallic particles of silicon face deposition, from preferential initiated oxidation reaction here, Si+2H
2o → SiO
2+ 4H
++ 4e
-;
SiO
2+6HF→H
2SiF
6+2H
2O;Si+6HF→H
2SiF
6+4H
++4e
-;
Total reaction is Si+H
2o
2+ 6HF → H
2siF
6+ 4H
2o.
Follow-up reaction process, metal ion does not participate in reaction, and the product of reaction is constantly transported by hydrofluoric acid, along with the carrying out of reaction, constantly sinks to bottom hole under gravity, finally forms Porous Silicon structures.
When porous silicon is prepared in the chemical corrosion of metal auxiliary catalysis, the aperture of required porous silicon preferably at 0.1-2 μm, but inevitably, there will be the pore structure of different size, usually comprises macropore silicon, mesoporous silicon and receiving bore silicon part.The aperture size of macropore silicon is at micron order, in poroid and columnar structure, the aperture size of mesoporous silicon is at 10-500nm, and the aperture of receiving bore silicon is at several ran, be made up of the Si crystal grain of the nanoscale of stochastic distribution, it has large specific surface area and very high chemically reactive.If but there is a large amount of receiving bore silicon in porous silicon, will cause also remaining nano pore structure in follow-up silicon wafer suede, these receiving bore can capture current carrier in the battery, cause that the resistance of silion cell increases, electric current declines, affect the efficiency of conversion of battery.Therefore, need to modify receiving bore silicon, remove.
Large based on receiving bore silicon specific surface area, chemically reactive is high, so as the polysilicon chip of vesicular structure and alkali lye or HNO
3during/HF reaction, by controlling concentration and the reaction times of the second treatment solution, preferentially receiving bore silicon can be removed, obtaining the polysilicon chip after vesicular structure modification.
Preferably, in the described second treatment solution A of step (1), described highly basic is KOH or NaOH.
Preferably, in the described second treatment solution A of step (1), the mass concentration of nitric acid is 10-20%, and the mass concentration of highly basic is 3-8%.
More preferably, in the described second treatment solution A of step (1), the mass concentration of nitric acid is 10%, and the mass concentration of highly basic is 5%.Described massfraction, refers to before unmixed formation processing liquid, the mass percent concentration of nitric acid, highly basic self.
Preferably, in the described second treatment solution B of step (1), the volume ratio 20-40:0.5-3:80-120 of nitric acid, hydrofluoric acid and water.
More preferably, in the described second treatment solution B of step (1), the volume ratio 30:1:100 of nitric acid, hydrofluoric acid and water.
Preferably, in described step (a), treatment temp is 20-34 DEG C, and the treatment time is 4-8min.
More preferably, in described step (a), treatment temp is 34 DEG C, and the treatment time is 4min.
Preferably, in described step (b), the modification time is 4-10min.
As described herein, in second step pre-treatment, namely when step (b) modifies Porous Silicon structures, in described second treatment solution A, B, all containing nitric acid, the effect of nitric acid is oxidized by the metallic particles such as copper, silver that silicon face is residual, obtains the metal ion of solubility, be convenient to be fallen by acid solution, deionized water rinsing.
Preferably, as use second treatment solution A, first process in the salpeter solution of described second treatment solution A, then process in the strong base solution of described second treatment solution A.
The making herbs into wool pretreatment process of diamond wire cutting polysilicon chip of the present invention is simple, and strong operability, the treatment time is short, and this making herbs into wool pretreatment process can match with the polysilicon chip of diamond cutting, and has good compatibility with existing silicon wafer wool making technique.There is uniform chemical damage layer, the sour leather producing process that recycling is conventional through the polysilicon chip that drilling-hole modification two-step method obtains, whole the uniform matte of corrosion can be obtained.
The third aspect, the invention provides a kind of making herbs into wool pre-treatment silicon chip, and described making herbs into wool pre-treatment silicon chip adopts the making herbs into wool pretreatment process described in second aspect present invention to obtain.
The present invention first forms vesicular structure by a single metal Assisted Chemical Etching Process technology on diamond wire cutting polysilicon chip surface, again vesicular structure is modified, obtain making herbs into wool pre-treatment silicon chip, the densely covered stria caused by the cutting of silicon chip surface diamond wire obtains planarization, forms the uniform affected layer of one deck.Described making herbs into wool pre-treatment silicon chip, can directly adopt existing RENA leather producing process to process, and obtains having whole the uniform matte of corrosion.
Fourth aspect, the invention provides the etching method of a kind of diamond wire cutting polysilicon chip, described etching method, comprises the making herbs into wool pretreatment process described in second aspect present invention, after described making herbs into wool pretreatment process, comprises conventional making herbs into wool further.
As described in the present invention, described conventional acid making herbs into wool adopts the mixing solutions of nitric acid, hydrofluoric acid and water to carry out making herbs into wool process.
As described in the present invention, the acid formula of described conventional leather producing process is: the volume ratio 5-15:1-5:5-10 of nitric acid, hydrofluoric acid and water, and making herbs into wool temperature is 5-10 DEG C, and the time is 90-150s, and the chemical equation of silicon chip acid leather producing process is:
4HNO
3+3Si=SiO
2+4NO
2+2H
2O;SiO
2+HF=H
2SiF
6+2H
2O;
H
2siF
6with water-soluble, form worm channel shape matte at silicon chip surface; Again at room temperature, with the KOH solution process 25-40s of mass concentration 5%, remove the porous silicon of silicon chip surface, then fall the alkali lye of remained on surface through deionized water rinsing; Finally use the mixing solutions process polysilicon chip 50-90s of HF and HCl, wherein the volume ratio of hydrofluoric acid, hydrochloric acid and water is 3:5:12, the various impurity metal ions etc. of removing silicon chip surface, and uses deionized water rinsing acidic surface.
The etching method of described diamond wire cutting polysilicon chip is simple, operability, practical, and this etching method and existing battery manufacturing process have good compatibility.
5th aspect, the invention provides a kind of diamond wire cutting polycrystalline silicon texturing product, and described diamond wire cutting polycrystalline silicon texturing product adopts the etching method described in fourth aspect present invention to obtain.
The matte of described diamond wire cutting polycrystalline silicon texturing product is even, reflectivity is low, can conveniently battery manufacturing procedure operation (comprising expansion phosphorus-trimming-depositing antireflection film etc.), described silicon wafer wool making production is become photovoltaic cell, the battery efficiency of the polysilicon chip that diamond wire is cut is unaffected, thus promotes the application of silicon wafer cut by diamond wire technology.
Compared with prior art, the present invention has following beneficial effect:
(1) proportioning of the making herbs into wool pretreatment fluid of described diamond wire cutting polysilicon chip is simple, and cost is low;
(2) the making herbs into wool pretreatment process of described diamond wire cutting polysilicon chip is simple, strong operability, and the treatment time is short, and this making herbs into wool pretreatment process and existing silicon wafer wool making technique have good compatibility;
(3) surface of described making herbs into wool pre-treatment silicon chip has the uniform affected layer of one deck, and the densely covered stria caused by diamond wire cutting obtains planarization;
(4) etching method of described diamond wire cutting polysilicon chip is simple, operability, practical, and this etching method and existing battery manufacturing process have good compatibility, have promoted the quick application of diamond wire cutting technique;
(5) diamond wire cutting polycrystalline silicon texturing product of the present invention, its matte is even, low about the 4-6% of diamond wire cutting polysilicon chip after the conventional making herbs into wool of luminance factor, the battery height 0.2-0.3% that the polysilicon chip that the cell photoelectric efficiency of conversion finally made is cut than diamond wire obtains through conventional leather producing process.
Summary of the invention
In cell fabrication processes, use for diamond wire saw polysilicon chip that existing RENA leather producing process cannot be formed evenly, the matte of antiradar reflectivity, the invention provides the making herbs into wool pretreatment fluid of a kind of diamond wire cutting polysilicon chip, making herbs into wool pretreatment process and making herbs into wool pre-treatment silicon chip and application thereof.
First aspect, the invention provides the making herbs into wool pretreatment fluid of a kind of diamond wire cutting polysilicon chip, described making herbs into wool treatment solution comprises the first treatment solution and the second treatment solution, first treatment solution is the mixing solutions of hydrofluoric acid, hydrogen peroxide, metal-salt and water, wherein, the volume ratio of hydrofluoric acid, hydrogen peroxide, water is 1-5:10-15:5-10, and in described first treatment solution, the volumetric molar concentration of metal ion is 5-100 μm of ol/L;
Second treatment solution comprises the second treatment solution A or the second treatment solution B, described second treatment solution A comprises nitric acid and highly basic, wherein, the mass concentration of nitric acid is 5-30%, the mass concentration of highly basic is 1-10%, described second treatment solution B is the mixing solutions of nitric acid, hydrofluoric acid and water, wherein, and the volume ratio 10-50:0.1-5:50-150 of nitric acid, hydrofluoric acid and water.
Preferably, in described first treatment solution, metal-salt comprises the one in cupric nitrate, Silver Nitrate, Palladous nitrate, cupric chloride, hydrochloro-auric acid and Platinic chloride.
More preferably, in described first treatment solution, metal-salt is Silver Nitrate.
Preferably, in described first treatment solution, the volumetric molar concentration of metal ion is 10-30 μm of ol/L.
Preferably, in described first treatment solution, the volume ratio of hydrofluoric acid, hydrogen peroxide, water is 2-4:12-14:6-9.
As described herein, if no special instructions, above-mentioned chemical all refers to streat drug, and massfraction is respectively: hydrofluoric acid is 49%, and hydrogen peroxide is 30%.Described massfraction, refers to before unmixed formation processing liquid, the mass percent concentration of hydrofluoric acid, hydrogen peroxide self.
Making herbs into wool pretreatment fluid proportioning of the present invention is simple, and cost is low, and described making herbs into wool pretreatment fluid can be used for process diamond wire cutting polysilicon chip, obtains uniform affected layer.
Second aspect, the invention provides the making herbs into wool pretreatment process of a kind of diamond wire cutting polysilicon chip, comprises the steps:
(1) first, second treatment solution is prepared:
Hydrofluoric acid, hydrogen peroxide, metal-salt and water are mixed, obtain the first treatment solution, wherein, the volume ratio of hydrofluoric acid, hydrogen peroxide, water is 1-5:10-15:5-10, and in described first treatment solution, the volumetric molar concentration of metal ion is 5-100 μm of ol/L;
Prepare nitric acid and strong base solution respectively, obtain the second treatment solution A, wherein, the mass concentration of nitric acid is 5-30%, and the mass concentration of highly basic is 1-10%; Nitric acid, hydrofluoric acid and water are mixed, obtains the second treatment solution B, wherein, the volume ratio 10-50:0.1-5:50-150 of nitric acid, hydrofluoric acid and water;
(2) pre-treatment:
A. Porous Silicon structures is prepared:
The polysilicon chip getting diamond wire cutting cleans, be placed in described first treatment solution and carry out pre-treatment, treatment temp is 10-50 DEG C, and the treatment time is 2-10min, obtains the polysilicon chip of vesicular structure;
B. vesicular structure is modified:
Get the polysilicon chip of the described vesicular structure of step (a), be placed in described second treatment solution A or the second treatment solution B, carry out the modification of surface porosity at normal temperatures, the modification time is 2-12min, obtain the polysilicon chip after vesicular structure modification, i.e. making herbs into wool pre-treatment polysilicon chip.
As described herein, if no special instructions, above-mentioned chemical all refers to streat drug, and massfraction is respectively: hydrofluoric acid is 49%, and nitric acid is about 69%, and hydrogen peroxide is 30%, hydrochloric acid 37%.
As described herein, in step (a), described cleaning, is adopt concentration to be that rare HF solution of 5-20% cleans, removes greasy dirt and the zone of oxidation of silicon chip surface.
As described herein, in described first treatment solution of step (1), metal-salt is the soluble salt of the metal of movable metallic after H.
Preferably, in described first treatment solution of step (1), metal-salt comprises the one in cupric nitrate, Silver Nitrate, Palladous nitrate, cupric chloride, hydrochloro-auric acid and Platinic chloride.
More preferably, in described first treatment solution, metal-salt is Silver Nitrate.
Preferably, in described first treatment solution of step (1), the volumetric molar concentration of metal ion is 10-30 μm of ol/L.
Preferably, in described first treatment solution of step (1), the volume ratio of hydrofluoric acid, hydrogen peroxide, water is 2-4:12-14:6-9.
More preferably, in described first treatment solution of step (1), the volumetric molar concentration of metal ion is 15 μm of ol/L.
More preferably, in described first treatment solution of step (1), the volume ratio of hydrofluoric acid, hydrogen peroxide, water is 3:13:8.
The present invention, in step (a), is adopt metal Assisted Chemical Etching Process technology to prepare the silicon chip of vesicular structure on polysilicon chip surface.
Accompanying drawing explanation
In order to be illustrated more clearly in the embodiment of the present invention or technical scheme of the prior art, be briefly described to the accompanying drawing used required in embodiment or description of the prior art below, apparently, accompanying drawing in the following describes is only some embodiments of the present invention, for those of ordinary skill in the art, under the prerequisite not paying creative work, other accompanying drawing can also be obtained according to these accompanying drawings.
Fig. 1 is surface scan Electronic Speculum (SEM) figure of the polysilicon chip of ordinary steel Linear cut;
Fig. 2 is the SEM figure after the frequent regulation suede of polysilicon chip of ordinary steel Linear cut;
Fig. 3 is the SEM figure of the polysilicon chip of diamond wire cutting;
Fig. 4 is the SEM figure after the frequent regulation suede of polysilicon chip of diamond wire cutting;
Fig. 5 is the SEM figure of the polysilicon chip in the embodiment of the present invention 1 after the first treatment solution process;
Fig. 6 is the SEM figure of making herbs into wool pre-treatment polysilicon chip in the embodiment of the present invention 1;
Fig. 7 is that the matte SEM of diamond wire cutting polycrystalline silicon texturing product in the embodiment of the present invention 1 schemes.
Embodiment
To be clearly and completely described technical scheme of the present invention below.Obviously, described embodiment is only the present invention's part embodiment, instead of whole embodiments.Based on the embodiment in the present invention, those of ordinary skill in the art, not making the every other embodiment obtained under creative work prerequisite, belong to the scope of protection of the invention.
Embodiment 1
A making herbs into wool pretreatment process for diamond wire cutting polysilicon chip, comprises the steps:
(1) first, second treatment solution is prepared:
Hydrofluoric acid, hydrogen peroxide, Silver Nitrate and water are mixed, obtains the first treatment solution, wherein, the volumetric molar concentration of silver ions is 15 μm of ol/L, the volume ratio of hydrofluoric acid, hydrogen peroxide, water is 3:13:8, and the mass concentration of hydrofluoric acid is 49%, and the mass concentration of hydrogen peroxide is 30%;
Prepare nitric acid and strong base solution respectively, obtain the second treatment solution A, wherein, the mass concentration of nitric acid is 10%, and the mass concentration of highly basic is 5%;
(2) pre-treatment:
A. Porous Silicon structures is prepared:
Get the polysilicon chip of diamond wire cutting, clean with rare HF solution that concentration is 10%, remove greasy dirt and the zone of oxidation of silicon chip surface, afterwards silicon chip is placed in described first treatment solution and carries out pre-treatment, treatment temp is 35 DEG C, treatment time is 5min, and with deionized water shower 2min, obtains the polysilicon chip of vesicular structure;
B. vesicular structure is modified:
Get the polysilicon chip of the vesicular structure described in step (a), be placed in described second treatment solution A, first normal temperature process 5min in the salpeter solution of 10%, use deionized water rinsing 2min afterwards, normal temperature process 4min in the KOH solution of 5% again, use deionized water rinsing 2min more afterwards, obtain the polysilicon chip after vesicular structure modification, i.e. making herbs into wool pre-treatment polysilicon chip.
The making herbs into wool pre-treatment polysilicon chip that above-mentioned pretreatment process process of learning from else's experience obtains, carries out following conventional making herbs into wool process:
Preparation mixed acid solution, the acid formula of conventional leather producing process is: the volume ratio 9:3:7 of nitric acid, hydrofluoric acid, water, in above-mentioned mixed acid solution, carry out making herbs into wool, and making herbs into wool temperature is 8 DEG C, and the time is 120s;
Use the KOH solution normal temperature process 25-40s of mass concentration 5% again, remove the receiving bore silicon of silicon chip surface, the mixing solutions (volume ratio of hydrofluoric acid, hydrochloric acid and water is 3:5:12) of hydrofluoric acid and hydrochloric acid is finally adopted to process 50-90s, the various impurity metal ions of removing silicon chip surface, obtain the cutting of the diamond wire after making herbs into wool polysilicon chip, i.e. diamond wire cutting polycrystalline silicon texturing product.
In the present embodiment, the mass concentration of hydrofluoric acid is 49%, and the mass concentration of nitric acid is 69%, and the mass concentration of hydrochloric acid is 37%, all refers to unmixed front concentration.
Fig. 5 is the SEM figure of the polysilicon chip in the embodiment of the present invention 1 after the first treatment solution process, as can be seen from Figure 5, the polysilicon chip of diamond wire cutting, after metal Aided Wet chemical etching, define the silicon chip of vesicular structure, its surface energy obviously observes mesoporous, macroporous structure, but still can have much tiny receiving bore; But after the second treatment solution process, obtain making herbs into wool pre-treatment polysilicon chip, from the SEM figure of Fig. 6, the nano pore structure on its surface disappears, and obtain the polysilicon chip after modifying, have uniform chemical damage layer, the thickness of affected layer is 5-6 μm.
Fig. 7 is that the matte SEM of the diamond wire cutting polycrystalline silicon texturing product that the polysilicon chip of diamond wire cutting obtains after leather producing process (pore-hole modification-conventional making herbs into wool) process of the present embodiment 1 schemes, as can be seen from Figure 7, the matte size distribution of described polycrystalline silicon texturing product is even, and matte is rounded.And the reflectivity of gained silicon chip is measured, the average reflectance under 400nm-1000nm wave band is 24%.The polysilicon chip of the diamond wire cutting after above-mentioned making herbs into wool is made battery, and the efficiency recording this battery is 17.95%.
Comparative example 1
In order to the effect of outstanding leather producing process of the present invention, as a comparison, get the polysilicon chip of diamond wire cutting, clean with rare HF solution that concentration is 10%, remove greasy dirt and the zone of oxidation of silicon chip surface, only adopt conventional leather producing process to carry out processing (the conventional making herbs into wool step with in embodiment 1) polysilicon chip after cleaning afterwards, obtain the polysilicon chip after making herbs into wool.
Adopt the diamond wire cutting polysilicon chip after the conventional leather producing process process of scanning electron microscopic observation, as shown in Figure 4, as can be seen from Figure 4, matte is more shallow for its suede structure, and shape is very irregular, and what have is worm channel shape, is also shown in obvious stria texture.And the reflectivity of silicon chip is measured, the average reflectance under 400nm-1000nm wave band is 29%, illustrates that the light trapping effect of silicon chip reduces greatly.
The polysilicon chip that the diamond wire of above-mentioned the conventional making herbs into wool process of process cuts is made battery, and the efficiency recording this battery is 17.66%.
Embodiment 2
A making herbs into wool pretreatment process for diamond wire cutting polysilicon chip, comprises the steps:
(1) first, second treatment solution is prepared:
Hydrofluoric acid, hydrogen peroxide, Silver Nitrate and water are mixed, obtains the first treatment solution, wherein, the volumetric molar concentration of silver ions is 15 μm of ol/L, the volume ratio of hydrofluoric acid, hydrogen peroxide, water is 3:13:8, and the mass concentration of hydrofluoric acid is 49%, and the mass concentration of hydrogen peroxide is 30%;
Nitric acid, hydrofluoric acid and water are mixed, obtains the second treatment solution B, wherein, the volume ratio 30:1:100 of nitric acid, hydrofluoric acid and water;
(2) pre-treatment:
A. Porous Silicon structures is prepared:
Get the polysilicon chip of diamond wire cutting, clean with rare HF solution that concentration is 10%, remove greasy dirt and the zone of oxidation of silicon chip surface, afterwards silicon chip is placed in described first treatment solution and carries out pre-treatment, treatment temp is 34 DEG C, treatment time is 5min, and with deionized water shower 2min, obtains the polysilicon chip of vesicular structure;
(2) vesicular structure is modified:
Get the polysilicon chip of the vesicular structure described in step (a), be placed in described second treatment solution B, process 4min at normal temperatures, use deionized water rinsing 2min more afterwards, obtain the polysilicon chip after vesicular structure modification, i.e. making herbs into wool pre-treatment polysilicon chip.
The making herbs into wool pre-treatment polysilicon chip that above-mentioned pretreatment process process of learning from else's experience obtains, carries out following conventional making herbs into wool process:
Preparation mixed acid solution, the acid formula of conventional leather producing process is: the volume ratio 9:3:7 of nitric acid, hydrofluoric acid, water, in above-mentioned mixed acid solution, carry out making herbs into wool, and making herbs into wool temperature is 8 DEG C, and the time is 90-150s; Use the KOH solution normal temperature process 25-40s of mass concentration 5% again, remove the receiving bore silicon of silicon chip surface, the mixing solutions (volume ratio of hydrofluoric acid, hydrochloric acid and water is 3:5:12) of hydrofluoric acid and hydrochloric acid is finally adopted to process 50-90s, the various impurity metal ions of removing silicon chip surface, obtain the cutting of the diamond wire after making herbs into wool polysilicon chip, i.e. diamond wire cutting polycrystalline silicon texturing product.
Measure the reflectivity of the present embodiment 2 gained diamond wire cutting polycrystalline silicon texturing product, the average reflectance under 400nm-1000nm wave band is 24.5%.Afterwards above-mentioned diamond wire cutting polycrystalline silicon texturing product is made battery, the efficiency recording this battery is 17.91%.
Other embodiments
By the technical scheme described in embodiment 2, making herbs into wool is carried out to the polysilicon chip of diamond wire cutting in embodiment 3-6, just design parameter is slightly different, refer to table 1, afterwards the mensuration of reflectivity is carried out to the silicon chip (i.e. diamond wire cutting polycrystalline silicon texturing product) after making herbs into wool, and polysilicon chip is made battery, the efficiency of battery is tested, refers to table 1.
By the technical scheme described in embodiment 1, making herbs into wool is carried out to the polysilicon chip of diamond wire cutting in embodiment 7-10, just design parameter is slightly different, refer to table 1, afterwards the mensuration of reflectivity is carried out to the silicon chip (i.e. diamond wire cutting polycrystalline silicon texturing product) after making herbs into wool, and polysilicon chip is made battery, the efficiency of battery is tested, refers to table 1.
Table 1
Above to invention has been detailed description; its object is to allow the personage being familiar with this art can understand content of the present invention and be implemented; can not limit the scope of the invention with this; the equivalence change that all spirit according to the present invention are done or modification, all should be encompassed in protection scope of the present invention.