阅读说明：本技术 一种perc双面太阳能电池及其制备方法 (A kind of PERC double-sided solar battery and preparation method thereof ) 是由 白玉磐 陈园 鲁军 付少剑 于 2019-09-06 设计创作，主要内容包括：本发明提供了一种PERC双面太阳能电池及其制备方法,其中,通过使所述PERC双面太阳能电池的正面绒面的形貌为类金字塔形；背面绒面的形貌为碗状,进而使得到的双面太阳能电池所制作的双玻组件单位辐照、单瓦功率的发电效率(PR)明显提高；且制备工艺简单,易于实现工业化生产。(The present invention provides a kind of PERC double-sided solar batteries and preparation method thereof, wherein by the pattern pyramid-like shape for making the front flannelette of the PERC double-sided solar battery；The pattern of back side flannelette be it is bowl-shape so as to double-sided solar battery made by solar double-glass assemblies unit irradiation, single watt of power generating efficiency (PR) significantly improve；And preparation process is simple, it is easy to accomplish industrialized production.)

1. a kind of PERC double-sided solar battery, which is characterized in that in the PERC double-sided solar battery, the shape of front flannelette Looks are pyramid-like shape；The pattern of back side flannelette is bowl-shape.

2. PERC double-sided solar battery according to claim 1, which is characterized in that the front micron order pyramid suede In face, tower width is 0.5~4 μm, and tower height is 0.5~3 μm.

3. PERC double-sided solar battery according to claim 1, which is characterized in that the back side flannelette is nanoscale bowl In shape flannelette, suede hole dia is 300~900nm, and suede hole depth is 200~500nm.

4. a kind of preparation method of PERC double-sided solar battery, comprising:

1) two silicon wafers are subjected to single side cleaning and making herbs into wool back-to-back, obtain the silicon wafer that front flannelette is pyramid flannelette；

2) silicon wafer for the positive making herbs into wool for obtaining step 1) carries out positive doping, obtains the silicon wafer of front doping；

3) silicon wafer of front doping is gone to obtain the silicon wafer that the back side is bowl-shape flannelette around plating and back side making herbs into wool；

4) silicon chip back side that the back side is bowl-shape flannelette is sequentially depositing aluminium oxide and silicon nitride；

5) silicon wafer for obtaining step 4) carries out silk-screen printing and sintering, obtains PERC double-sided solar battery.

5. the preparation method according to claim 4, which is characterized in that the front making herbs into wool is lye with reaction system and contains The reaction system of isopropanol additive, wherein the lye is potassium hydroxide aqueous solution or sodium hydrate aqueous solution.

6. the preparation method according to claim 4, which is characterized in that the temperature of making herbs into wool is 80~85 in the step 1) ℃。

7. the preparation method according to claim 4, which is characterized in that in the silicon wafer of the front doping, matrix silicon face The N-type silicon of formation with a thickness of 0.2~0.4 μm.

8. the preparation method according to claim 4, which is characterized in that back side making herbs into wool is using MCCE method in the step 3) Carry out making herbs into wool.

9. the preparation method according to claim 4, which is characterized in that the aluminium oxide of the backside deposition with a thickness of 50~ 90nm。

10. the preparation method according to claim 4, which is characterized in that the silicon nitride of the backside deposition with a thickness of 70 ~90nm.

Technical field

The present invention relates to area of solar cell more particularly to a kind of PERC double-sided solar battery and preparation method thereof.

Background technique

It pursues and improves battery conversion efficiency, while reducing even maintenance manufacturing cost is the target and mention that industry is constantly pursued The place of itself high competitiveness.Relative to the conventional crystal silicon solar cell of single side light, double-sided solar battery using just, Two light-receiving surfaces are carried on the back, higher density of photocurrent can be obtained, largely improve generated output.

Double-side solar cell structure include the flannelette appearance structure of front and back, PN junction emitter, passivated reflection reducing dielectric layer, Front and back electrode etc..Wherein, the flannelette at the back side can effectively improve ground and Ambient in the suction at the double-side cell back side It receives, is the important feature of double-side solar cell.At present there are two types of the backside structures of double-sided solar battery, the first is that the back side is thrown Light, no suede structure, as shown in FIG. 1, FIG. 1 is the PERC double-sided solar battery structure charts that the back side is smooth surface for structure；It is prepared Technique is as follows: alkali making herbs into wool, forms the flannelette of micron level in silicon chip surface；2) diffusing, doping adulterates one layer in silicon wafer front surface 0.3 μm or so of N-type silicon；3) etching trimming cleaning, removes the N-type silicon of silicon chip back side and side using wet etching；4) table afterwards Face deposits A12O3 passivating film+SixNy antireflective coating in the way of PECVD；5) front surface deposits SixNy film using PECVD； 6) laser carries out differential trench open to back side Al2O3 and SixNy film；7) front surface prints electrode, and rear surface prints back electrode；Separately A kind of PERC double-sided solar battery is using the pyramid flannelette appearance structure similar with front, as shown in Fig. 2, Fig. 2 is back Face is the PERC double-sided solar battery of similar pyramid flannelette；Wherein, 100 be monocrystalline substrate, and 1 is positive wheat flour suede pattern knot Structure, 2 be front doping emitter junction, and 3 be front passivated reflection reducing dielectric layer, and 4 be front electrode, and 5 be back side making herbs into wool appearance structure, 5a is platform structure, and 6 be back surface field, and 7 be passivating back anti-reflection dielectric layer, and 8 be rear electrode.But it is presently disclosed The incident photon-to-electron conversion efficiency raising of PERC double-sided solar battery is not obvious, and how further to improve PERC double-sided solar electricity The performance in pond is still current problem to be solved.

Summary of the invention

In view of this, technical problem to be solved by the present invention lies in provide a kind of PERC double-sided solar battery and its system Preparation Method, solar battery provided by the invention have high incident photon-to-electron conversion efficiency.

The present invention provides a kind of PERC double-sided solar batteries, which is characterized in that the PERC double-sided solar battery In, the pattern of front flannelette is pyramid-like shape；The pattern of back side flannelette is bowl-shape.

Preferably, the front tower width is 0.5~4 μm, and tower height is 0.5~3 μm.

Preferably, the back side suede hole dia is 300~900nm, and suede hole depth is 200~500nm.

The present invention also provides a kind of preparation methods of PERC double-sided solar battery, comprising:

1) two silicon wafers are subjected to single side cleaning and making herbs into wool back-to-back, obtain the silicon wafer that front flannelette is pyramid flannelette；

2) silicon wafer for the positive making herbs into wool for obtaining step 1) carries out positive doping, obtains the silicon wafer of front doping；

3) silicon wafer of front doping is gone to obtain the silicon wafer that the back side is bowl-shape flannelette around plating and back side making herbs into wool；

4) silicon chip back side that the back side is bowl-shape flannelette is sequentially depositing aluminium oxide and silicon nitride；

5) silicon wafer for obtaining step 4) carries out silk-screen printing and sintering, obtains PERC double-sided solar battery.

Preferably, the positive making herbs into wool is the reaction system of lye and the additive containing isopropanol with reaction system, wherein institute Stating lye is potassium hydroxide aqueous solution or sodium hydrate aqueous solution.

Preferably, the temperature of making herbs into wool is 80~85 DEG C in the step 1).

Preferably, it is described front doping silicon wafer in, matrix silicon face formed N-type silicon with a thickness of 0.2~0.4 μm.

Preferably, back side making herbs into wool is to carry out making herbs into wool using MCCE method in the step 3).

Preferably, the aluminium oxide of the backside deposition with a thickness of 50~90nm.

Preferably, the silicon nitride of the backside deposition with a thickness of 70~90nm.

Compared with prior art, the present invention provides a kind of PERC double-sided solar batteries, wherein by making the PERC The pattern of the front flannelette of double-sided solar battery is pyramid-like shape；The pattern of back side flannelette is bowl-shape, so that arrive Solar double-glass assemblies unit made by double-sided solar battery irradiates, the generating efficiency (PR) of single watt of power significantly improves, experiment knot Fruit shows that solar double-glass assemblies PR made by double-sided solar battery provided by the invention promotes 2~5% percentage points.

Detailed description of the invention

Fig. 1 is the PERC double-sided solar battery structure chart that the back side is smooth surface；

Fig. 2 is the PERC double-sided solar battery that the back side is similar pyramid flannelette；

The structural schematic diagram for the solar battery that Fig. 3 is；

Fig. 4 is the positive flannelette shape appearance figure of PERC double-sided solar battery；

Fig. 5 is the flannelette shape appearance figure at the PERC double-sided solar battery back side.

Specific embodiment

The present invention provides a kind of PERC double-sided solar batteries, wherein in the PERC double-sided solar battery, front The pattern of flannelette is pyramid-like shape；The pattern of back side flannelette is bowl-shape.

According to the present invention, in double-sided solar battery of the present invention, the front flannelette is preferably micron-sized ruler It is very little；In the front micron order pyramid flannelette, tower width is 0.5~4 μm, and tower height is 0.5~3 μm, preferably 1~2 μm；Institute Stating back side flannelette is preferably nanoscale size；The back side flannelette be the bowl-shape flannelette of nanoscale in, suede hole dia be 300~ 900nm, suede hole depth are 200~500nm.In the present invention, the present invention sends out the other structures in double-sided solar battery, such as PN junction Emitter-base bandgap grading, passivated reflection reducing dielectric layer, front electrode and rear electrode do not have particular/special requirement, and those skilled in the art can be according to reality Border experiment condition etc. selects each layer of composition and thickness.

The present invention also provides a kind of preparation methods of PERC double-sided solar battery, comprising:

1) two silicon wafers are subjected to single side cleaning and making herbs into wool back-to-back, obtain the silicon wafer that front flannelette is pyramid flannelette；

2) silicon wafer for the positive making herbs into wool for obtaining step 1) carries out positive doping, obtains the silicon wafer of front doping；

3) silicon wafer of front doping is gone to obtain the silicon wafer that the back side is bowl-shape flannelette around plating and back side making herbs into wool；

4) silicon chip back side that the back side is bowl dress flannelette is sequentially depositing aluminium oxide and silicon nitride；

5) silicon wafer for obtaining step 4) carries out silk-screen printing and sintering, obtains PERC double-sided solar battery.

According to the present invention, two silicon wafers are carried out single side cleaning and making herbs into wool by the present invention back-to-back, obtain front flannelette as gold The silicon wafer of word tower flannelette；Wherein, the positive making herbs into wool is the reaction system of lye and the additive containing isopropanol with reaction system；Institute Stating lye is potassium hydroxide aqueous solution or sodium hydrate aqueous solution；The temperature of making herbs into wool is 80~85 DEG C in the step 1)；This hair In bright, further include that the two panels silicon wafer for finishing making herbs into wool separates, clean in an acidic solution, to remove surface impurity.In the present invention, By the way that two silicon wafers are carried out single side cleaning or making herbs into wool back-to-back, corrosion of the Woolen-making liquid to back side silicon wafer is avoided, silicon wafer is reduced Loss of weight it is more difficult to lose so that the silicon wafer substrate of obtained solar battery is thicker.

According to the present invention, the silicon wafer for the positive making herbs into wool that the present invention also obtains step 1) carries out positive doping, obtains front The silicon wafer of doping；Wherein, it is POCl that the front, which is doped with dopant,₃, it is described front doping silicon wafer in, matrix silicon face shape At N-type silicon with a thickness of 0.2~0.4 μm, more preferably 0.25~0.3 μm；The front doping is specific: utilizing POCl₃For Dopant is passed through O in diffusion process₂, the two, which is reacted, generates P elements, diffuses into inside silicon wafer, makes under the high temperature conditions Matrix silicon face forms the N-type silicon of 0.3 μm of left and right thickness, and then forms cell piece nuclear structure PN junction, particularly, after matching Continuous passivation membrane process, diffusing procedure use and (N are lightly doped_d< 10e21).

According to the present invention, the present invention also goes the silicon wafer of front doping around plating and back side making herbs into wool, and obtaining the back side is bowl The silicon wafer of shape flannelette, wherein described to go around plating to be HF/HNO with reaction system₃System；After completing retrial, the present invention uses MCCE Method carries out back side making herbs into wool, obtains the silicon wafer of bowl dress flannelette；In the present invention, the present invention also carries out the silicon wafer after the making herbs into wool of the back side with HF Cleaning, removes the phosphorosilicate glass on surface.

According to the present invention, the silicon chip back side that the back side is bowl dress flannelette is also sequentially depositing aluminium oxide and silicon nitride by the present invention； Wherein, the aluminium oxide of the backside deposition with a thickness of 5~30nm, preferably 10~25nm；The silicon nitride of the backside deposition With a thickness of 50~90nm, preferably 70~80nm；Specifically, the method for deposition of aluminium oxide of the present invention and silicon nitride are as follows: use PECVD cvd furnace, with TMA and N₂O is reactant, carries out Al to the back side₂O₃Deposition, thickness control is in 5~30nm, temperature control At 250~350 DEG C, with SiH₄And NH₃For reactant, in Al₂O₃Upper progress SixNy deposition, thickness control 50~90nm it Between, to obtain best passivation, anti-reflective effect, temperature is controlled at 400~450 DEG C.Upper surface deposits SiNx, with SiH₄With NH₃For reactant, thickness control, to obtain best anti-reflective effect, is particularly depositing SixNy between 70~90nm Preceding to be made annealing treatment, specifically, the temperature of annealing is maintained between 400~500 DEG C.

According to the present invention, the silicon wafer that the present invention also obtains step 4) carries out silk-screen printing and sintering, and it is two-sided to obtain PERC Solar battery；For the present invention to the method for silk-screen printing and sintering there is no particular/special requirement, those skilled in the art can basis Actual needs takes suitable method, such as can be with: carrying out slot treatment to back surface using laser, specifically, control laser function The size of rate can just melt the Al of passivation dielectric layer₂O₃And SixNy, it is not damaged to matrix silicon, the figure of processing and the back side The pattern of alum gate line and back electrode carries out matching fluting；Front surface prints Ag electrode, and back surface prints A1 grid line and Ag electrode, special Not, the front surface Ag slurry is high contact performance slurry, to match being lightly doped for diffusing procedure, the figure of Al grid line printing Matching Chong Die with laser ablation open area, the printing of Ag back electrode are matched to laser non-open areas.

PERC double-sided solar battery provided by the invention, by the front flannelette for making the PERC double-sided solar battery Pattern be pyramid-like shape；The pattern of back side flannelette is bowl-shape, so that the photoelectricity of obtained double-sided solar battery turns Change efficiency to significantly improve；And preparation method provided by the invention is simple, obtained finished product rate is high, it is easy to accomplish industrial metaplasia It produces.

It is clearly and completely described below in conjunction with the technical solution of the embodiment of the present invention, it is clear that described implementation Example is only a part of the embodiment of the present invention, instead of all the embodiments.Based on the embodiments of the present invention, this field is common Technical staff's every other embodiment obtained without making creative work belongs to the model that the present invention protects It encloses.