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CN106835286B - A double-sided diffusion process for solar cells - Google Patents

A double-sided diffusion process for solar cells Download PDF

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Publication number
CN106835286B
CN106835286B CN201611234462.5A CN201611234462A CN106835286B CN 106835286 B CN106835286 B CN 106835286B CN 201611234462 A CN201611234462 A CN 201611234462A CN 106835286 B CN106835286 B CN 106835286B
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crystalline silicon
double
diffusion
silicon wafers
ceramic crucible
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CN106835286A (en
Inventor
樊华
王丹萍
蒋志强
徐建
钱明明
彭彪
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Huansheng Photovoltaic Jiangsu Co Ltd
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Eastern Link Photovoltaic (jiangsu) Co Ltd
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    • C—CHEMISTRY; METALLURGY
    • C30—CRYSTAL GROWTH
    • C30B—SINGLE-CRYSTAL GROWTH; UNIDIRECTIONAL SOLIDIFICATION OF EUTECTIC MATERIAL OR UNIDIRECTIONAL DEMIXING OF EUTECTOID MATERIAL; REFINING BY ZONE-MELTING OF MATERIAL; PRODUCTION OF A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; SINGLE CRYSTALS OR HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; AFTER-TREATMENT OF SINGLE CRYSTALS OR A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; APPARATUS THEREFOR
    • C30B31/00—Diffusion or doping processes for single crystals or homogeneous polycrystalline material with defined structure; Apparatus therefor
    • C30B31/02—Diffusion or doping processes for single crystals or homogeneous polycrystalline material with defined structure; Apparatus therefor by contacting with diffusion materials in the solid state
    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10F—INORGANIC SEMICONDUCTOR DEVICES SENSITIVE TO INFRARED RADIATION, LIGHT, ELECTROMAGNETIC RADIATION OF SHORTER WAVELENGTH OR CORPUSCULAR RADIATION
    • H10F71/00—Manufacture or treatment of devices covered by this subclass
    • H10F71/137—Batch treatment of the devices
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E10/00—Energy generation through renewable energy sources
    • Y02E10/50—Photovoltaic [PV] energy
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
    • Y02P70/00—Climate change mitigation technologies in the production process for final industrial or consumer products
    • Y02P70/50—Manufacturing or production processes characterised by the final manufactured product

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  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Materials Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Photovoltaic Devices (AREA)

Abstract

本发明公开了一种太阳能电池的双面扩散工艺，该工艺采用的固态杂质源氧化镓，该杂质性能稳定，成分简单，均匀性好，工艺过程工艺简洁，成本低，易与现有生产线和生产设备相兼容。The invention discloses a double-sided diffusion process for solar cells. The process adopts gallium oxide as a solid impurity source. The impurity has stable performance, simple composition, good uniformity, simple process and low cost, and is easily compatible with existing production lines. Compatible with production equipment.

Description

A kind of Double side diffusion technique of solar battery
Technical field
The present invention relates to photovoltaic technology field, the Double side diffusion technique of specifically a kind of solar battery.
Background technique
Traditional crystal silicon solar batteries boron diffusion (N-type silicon substrate) technique is generally single side diffusion, does not need to spread The surface of impurity is placed in carrier face-to-face, is only carried out boron to the light-receiving surface of solar battery in diffusion furnace and is spread to be formed Emitter, and cell backside heavy doping passivation, double-side cell, N-type cell etc. are required to two sides diffusion and carry out different impurity members The advantages of element diffusion, Double side diffusion is gettering can both to be carried out to non-illuminated surface, and then improve cell voltage output, and can two sides Incident light is received, so that the overall output power of solar cell array be made to improve 10-30%.Currently, using two-sided impurity diffusion, General auxiliary is starched with silk-screen printing, liquid gas phase two ways, patent CN201210127523.3 using boron, is assisted with silk-screen printing Mode makes, and realizes the single side battery of back side boron element heavy doping；By liquid vapor mode just like document number CN200910034985.9 is successively to carry boron source by inert gas to carry out liquid gas phase diffusion.Either screen printing mode, Or gas phase takes source mode, and the doping on required surface could be completed by requiring 2-4 step process, and process is complicated, is unfavorable for industrialization.
Compared to above two existing more typical diffusion way, impurity element is carried using coating to make impurity diffusion Layer, coating fluid in the prior art etc. there are unstable, easily occur denaturation, reunite, precipitating the disadvantages of, and complicated component is used At high cost in diffusion technique, process is complicated, is unfavorable for industrialized production and is combined with prior art.
Summary of the invention
The purpose of the present invention is to provide the solid-states that a kind of Double side diffusion technique of N-type solar battery, the technique use Impurity source gallium oxide, the impurity performance are stablized, and ingredient is simple, and uniformity is good, technical process concise in technology, at low cost, Yi Yuxian There is production line to be mutually compatible with production equipment.
Above-mentioned purpose of the invention is to be implemented by following technical measures to realize: a kind of realization N-type silicon chip is two-sided Diffusion technique contains following steps:
A kind of Double side diffusion technique of solar battery, it is using solid oxide gallium as impurity source.
It more preferably, further include the forming step of a SiO2 oxide layer before Double side diffusion step.
Specifically, Double side diffusion processing step of the invention are as follows:
A) crystal silicon chip pre-processes: choosing N-type crystalline silicon piece, will clean after crystal silicon chip making herbs into wool；
B) oxide layer is formed: the obtained crystal silicon chip of step a) is put into the quartz ampoule of oxidation operation, reaction condition: O2: 8~10L/M, H2: 12~14L/M, t:50~60min, T:850 DEG C；
C) Double side diffusion: the gallium oxide powder for being used to spread source is put into ceramic crucible, by ceramic crucible and step b) Obtained crystal silicon chip is packed into quartz ampoule together, reaction condition: T=1150 DEG C of t=85~95min, N2=600~700ml/ min H2: 65~75ml/min, square resistance: 40~50 Ω/sq.
In a specific embodiment, Double side diffusion processing step are as follows:
A) crystal silicon chip pre-processes: choosing N-type crystalline silicon piece, will clean after crystal silicon chip making herbs into wool；
B) oxide layer is formed: the obtained crystal silicon chip of step a) is put into the quartz ampoule of oxidation operation, reaction condition: O2: 8L/M, H2: 12L/M, t:50min, T:850 DEG C；
C) Double side diffusion: the gallium oxide powder for being used to spread source is put into ceramic crucible, by ceramic crucible and step b) Obtained crystal silicon chip is packed into quartz ampoule together, reaction condition: T=1150 DEG C of t=85min, N2=600ml/min H2: 65ml/min, square resistance: 50 Ω/sq.
In another specific embodiment, Double side diffusion processing step are as follows:
A) crystal silicon chip pre-processes: choosing N-type crystalline silicon piece, will clean after crystal silicon chip making herbs into wool；
B) oxide layer is formed: the obtained crystal silicon chip of step a) is put into the quartz ampoule of oxidation operation, reaction condition: O2: 10L/M, H2: 14L/M, t:60min, T:850 DEG C；
C) Double side diffusion: the gallium oxide powder for being used to spread source is put into ceramic crucible, by ceramic crucible and step b) Obtained crystal silicon chip is packed into quartz ampoule together, reaction condition: T=1150 DEG C of t=95min, N2=700ml/min H2: 75ml/min, square resistance: 40 Ω/sq.
Beneficial effects of the present invention:
Impurity source of the invention is solid oxide gallium, spreads feature using Si/SiO2: what gallium was quickly spread in the si 02 layer Characteristic, low gallium doping and the passage of junction depth are to complete the diffusion of low concentration shallow junction, reduce impurity gradient before tying, to improve out pressure, Improve transfer efficiency.
For diffusion furnace of the present invention using Closed Tube Diffusion furnace, the uniformity of diffusion is very good, in piece, between piece, batch between square The even property of resistance has reached ± 3% range, and quality is particularly stable；The sealing effect and reliability of high-temperature diffusion process lower furnace door are special Not good, tail gas is drained by tail portion centralized collection completely in technique, and environment protecting is obvious.
The present invention increases by one of oxidation operation in conventional batteries technique, and the mode of oxidizing synthesized using hydrogen-oxygen forms one layer SiO2 oxide layer can play the effect being centainly passivated.
Specific embodiment
Below in conjunction with specific embodiment, the invention will be further described.
Embodiment 1: a kind of Double side diffusion technique of solar battery, step are as follows:
A) crystal silicon chip pre-processes: choosing N-type crystalline silicon piece, will clean after crystal silicon chip making herbs into wool；
B) oxide layer is formed: the obtained crystal silicon chip of step a) is put into the quartz ampoule of oxidation operation, reaction condition: O2: 8-10L/M (oxygen flow, unit liter/min, similarly hereinafter), H2: 10-12L/M (hydrogen flowing quantity, unit liter/min, similarly hereinafter), T:45-50min (duration, similarly hereinafter), T:840-850 DEG C (temperature, similarly hereinafter)；
C) Double side diffusion: the gallium oxide powder for being used to spread source is put into ceramic crucible, by ceramic crucible and step b) Obtained crystal silicon chip is packed into quartz ampoule together, reaction condition: T=1150 DEG C of t=85min, N2=600-700ml/min (nitrogen flow, unit ml/min, similarly hereinafter) H2: 50-60ml/min (hydrogen flowing quantity, unit ml/min, similarly hereinafter), square Resistance: 50 Ω/sq.
Double side diffusion is carried out using gallium oxide powder, is operated under the reaction condition of the present embodiment, transfer efficiency reaches 20.0%
Further, the present invention increases by one of oxidation operation in conventional batteries technique, the mode of oxidizing synthesized using hydrogen-oxygen, One layer of SiO2 oxide layer is formed, the effect being centainly passivated can be played.
Embodiment 2: a kind of Double side diffusion technique of solar battery, step are as follows:
A) crystal silicon chip pre-processes: choosing N-type crystalline silicon piece, will clean after crystal silicon chip making herbs into wool；
B) oxide layer is formed: the obtained crystal silicon chip of step a) is put into the quartz ampoule of oxidation operation, reaction condition: O2: 10L/M, H2: 14L/M, t:60min, T:850 DEG C；
C) Double side diffusion: the gallium oxide powder for being used to spread source is put into ceramic crucible, by ceramic crucible and step b) Obtained crystal silicon chip is packed into quartz ampoule together, reaction condition: T=1150 DEG C of t=95min, N2=700ml/min H2: 75ml/min, square resistance: 40 Ω/sq.
Double side diffusion is carried out using gallium oxide powder, is operated under the reaction condition of the present embodiment, transfer efficiency reaches 20.0%.
Embodiment 3: a kind of Double side diffusion technique of solar battery, step are as follows:
A) crystal silicon chip pre-processes: choosing N-type crystalline silicon piece, will clean after crystal silicon chip making herbs into wool；
B) oxide layer is formed: the obtained crystal silicon chip of step a) is put into the quartz ampoule of oxidation operation, reaction condition: O2: 9L/M, H2: 13L/M, t:55min, T:850 DEG C；
C) Double side diffusion: the gallium oxide powder for being used to spread source is put into ceramic crucible, by ceramic crucible and step b) Obtained crystal silicon chip is packed into quartz ampoule together, reaction condition: T=1150 DEG C of t=90min, N2=650ml/min H2: 70ml/min, square resistance: 45 Ω/sq.
Double side diffusion is carried out using gallium oxide powder, is operated under the reaction condition of the present embodiment, transfer efficiency reaches 20.0%.
The above examples are only used to illustrate the technical scheme of the present invention, rather than limiting the scope of the invention, although The present invention is explained in detail referring to preferred embodiment, those skilled in the art should understand that, it can be to this hair Bright technical solution is modified or equivalent replacement, without departing from the spirit and scope of technical solution of the present invention.

Claims (3)

1.一种太阳能电池的双面扩散工艺，其特征在于它采用固态氧化镓作为杂质源，双面扩散步骤前还包括一个SiO2氧化层的形成步骤；太阳能电池的双面扩散工艺的具体步骤为：1. a double-sided diffusion process of solar cell is characterized in that it adopts solid-state gallium oxide as impurity source, and also comprises a SiO before the double-sided diffusion step The formation step of oxide layer; The concrete steps of the double-sided diffusion process of solar cell are as follows: : a)晶体硅片预处理：选取N型晶体硅片，将晶体硅片制绒后清洗；a) Pretreatment of crystalline silicon wafers: N-type crystalline silicon wafers are selected, and the crystalline silicon wafers are textured and then cleaned; b)氧化层形成：将步骤a)得到的晶体硅片放入氧化工序的石英管内，反应条件：O2：8～10L/M，H2：12～14L/M，t：50～60min，T：850℃；b) Oxidation layer formation: put the crystalline silicon wafer obtained in step a) into the quartz tube of the oxidation process, reaction conditions: O 2 : 8-10L/M, H 2 : 12-14L/M, t: 50-60min, T: 850℃; c)双面扩散：将用于扩散源的氧化镓粉末放入陶瓷坩埚中，将陶瓷坩埚和步骤b)得到的晶体硅片一起装入石英管内，反应条件：T＝1150℃t＝85～95min，N2＝600～700ml/minH2：65～75ml/min，方块电阻：40～50Ω/sq。c) Double-sided diffusion: put the gallium oxide powder used as a diffusion source into a ceramic crucible, and put the ceramic crucible and the crystalline silicon wafer obtained in step b) into a quartz tube together, reaction conditions: T=1150°C t=85～ 95min, N 2 =600～700ml/minH 2 : 65～75ml/min, sheet resistance: 40～50Ω/sq. 2.根据权利要求1所述的一种太阳能电池的双面扩散工艺，其特征在于其步骤为：2. The double-sided diffusion process of a solar cell according to claim 1, wherein the steps are: a)晶体硅片预处理：选取N型晶体硅片，将晶体硅片制绒后清洗；a) Pretreatment of crystalline silicon wafers: N-type crystalline silicon wafers are selected, and the crystalline silicon wafers are textured and then cleaned; b)氧化层形成：将步骤a)得到的晶体硅片放入氧化工序的石英管内，反应条件：O2：8L/M，H2：12L/M，t：50min，T：850℃；b) Oxidation layer formation: put the crystalline silicon wafer obtained in step a) into the quartz tube of the oxidation process, reaction conditions: O 2 : 8L/M, H 2 : 12L/M, t: 50min, T: 850°C; c)双面扩散：将用于扩散源的氧化镓粉末放入陶瓷坩埚中，将陶瓷坩埚和步骤b)得到的晶体硅片一起装入石英管内，反应条件：T＝1150℃t＝85min，N2＝600ml/min H2：65ml/min，方块电阻：50Ω/sq。c) Double-sided diffusion: put the gallium oxide powder used as a diffusion source into a ceramic crucible, and put the ceramic crucible and the crystalline silicon wafer obtained in step b) into a quartz tube together, reaction conditions: T=1150°C t=85min, N 2 =600ml/min H 2 : 65ml/min, sheet resistance: 50Ω/sq. 3.根据权利要求2所述的一种太阳能电池的双面扩散工艺，其特征在于其步骤为：3. The double-sided diffusion process of a solar cell according to claim 2, wherein the steps are: a)晶体硅片预处理：选取N型晶体硅片，将晶体硅片制绒后清洗；a) Pretreatment of crystalline silicon wafers: N-type crystalline silicon wafers are selected, and the crystalline silicon wafers are textured and then cleaned; b)氧化层形成：将步骤a)得到的晶体硅片放入氧化工序的石英管内，反应条件：O2：10L/M，H2：14L/M，t：60min，T：850℃；b) Oxidation layer formation: put the crystalline silicon wafer obtained in step a) into the quartz tube of the oxidation process, reaction conditions: O 2 : 10L/M, H 2 : 14L/M, t: 60min, T: 850°C; c)双面扩散：将用于扩散源的氧化镓粉末放入陶瓷坩埚中，将陶瓷坩埚和步骤b)得到的晶体硅片一起装入石英管内，反应条件：T＝1150℃t＝95min，N2＝700ml/min H2：75ml/min，方块电阻：40Ω/sq。c) Double-sided diffusion: put the gallium oxide powder used as a diffusion source into a ceramic crucible, and put the ceramic crucible and the crystalline silicon wafer obtained in step b) into a quartz tube together, reaction conditions: T=1150°C t=95min, N 2 =700ml/min H 2 : 75ml/min, sheet resistance: 40Ω/sq.
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Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1036294A (en) * 1988-04-02 1989-10-11 山东师范大学 The application technology of gallium in angle beveled mesa structure silicon pn junction is produced
CN1529345A (en) * 2003-10-10 2004-09-15 沈首良 Method and device for preparing high power semiconductor device by open-tube diffusion
CN1828846A (en) * 2006-01-16 2006-09-06 山东师范大学 Oxidation and gallium expansion one-step process for manufacturing semiconductor devices

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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
TWI483345B (en) * 2008-05-07 2015-05-01 Univ Nat Chiao Tung Method for fabricating complementary gold-oxygen half-field effect transistor with very low threshold voltage metal gate/high dielectric constant material by using automatic alignment low temperature shallow junction
CN103718309B (en) * 2011-07-25 2018-05-18 日立化成株式会社 Semiconductor substrate and manufacturing method thereof, solar cell element, and solar cell

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1036294A (en) * 1988-04-02 1989-10-11 山东师范大学 The application technology of gallium in angle beveled mesa structure silicon pn junction is produced
CN1529345A (en) * 2003-10-10 2004-09-15 沈首良 Method and device for preparing high power semiconductor device by open-tube diffusion
CN1828846A (en) * 2006-01-16 2006-09-06 山东师范大学 Oxidation and gallium expansion one-step process for manufacturing semiconductor devices

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Address after: 214203 No. 20 Wen Zhuang Road, Yixing Economic Development Zone, Jiangsu, Wuxi

Patentee after: Huansheng photovoltaic (Jiangsu) Co., Ltd

Address before: 214203 No. 20 Wen Zhuang Road, Yixing Economic Development Zone, Jiangsu, Wuxi

Patentee before: Eastern link photovoltaic (Jiangsu) Co., Ltd.