CN107735866B - 太阳能电池 - Google Patents

太阳能电池 Download PDF

Info

Publication number
CN107735866B
CN107735866B CN201680031268.9A CN201680031268A CN107735866B CN 107735866 B CN107735866 B CN 107735866B CN 201680031268 A CN201680031268 A CN 201680031268A CN 107735866 B CN107735866 B CN 107735866B
Authority
CN
China
Prior art keywords
type
layer
silicon substrate
crystalline silicon
solar cell
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Active
Application number
CN201680031268.9A
Other languages
English (en)
Other versions
CN107735866A (zh
Inventor
马场俊明
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Panasonic Intellectual Property Management Co Ltd
Original Assignee
Panasonic Intellectual Property Management Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Panasonic Intellectual Property Management Co Ltd filed Critical Panasonic Intellectual Property Management Co Ltd
Publication of CN107735866A publication Critical patent/CN107735866A/zh
Application granted granted Critical
Publication of CN107735866B publication Critical patent/CN107735866B/zh
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Classifications

    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L31/00Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof
    • H01L31/02Details
    • H01L31/0216Coatings
    • H01L31/02161Coatings for devices characterised by at least one potential jump barrier or surface barrier
    • H01L31/02167Coatings for devices characterised by at least one potential jump barrier or surface barrier for solar cells
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L31/00Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof
    • H01L31/02Details
    • H01L31/0216Coatings
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L31/00Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof
    • H01L31/02Details
    • H01L31/0224Electrodes
    • H01L31/022408Electrodes for devices characterised by at least one potential jump barrier or surface barrier
    • H01L31/022425Electrodes for devices characterised by at least one potential jump barrier or surface barrier for solar cells
    • H01L31/022441Electrode arrangements specially adapted for back-contact solar cells
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L31/00Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof
    • H01L31/0248Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof characterised by their semiconductor bodies
    • H01L31/0256Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof characterised by their semiconductor bodies characterised by the material
    • H01L31/0264Inorganic materials
    • H01L31/028Inorganic materials including, apart from doping material or other impurities, only elements of Group IV of the Periodic System
    • H01L31/0288Inorganic materials including, apart from doping material or other impurities, only elements of Group IV of the Periodic System characterised by the doping material
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L31/00Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof
    • H01L31/04Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof adapted as photovoltaic [PV] conversion devices
    • H01L31/06Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof adapted as photovoltaic [PV] conversion devices characterised by at least one potential-jump barrier or surface barrier
    • H01L31/068Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof adapted as photovoltaic [PV] conversion devices characterised by at least one potential-jump barrier or surface barrier the potential barriers being only of the PN homojunction type, e.g. bulk silicon PN homojunction solar cells or thin film polycrystalline silicon PN homojunction solar cells
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L31/00Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof
    • H01L31/04Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof adapted as photovoltaic [PV] conversion devices
    • H01L31/06Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof adapted as photovoltaic [PV] conversion devices characterised by at least one potential-jump barrier or surface barrier
    • H01L31/072Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof adapted as photovoltaic [PV] conversion devices characterised by at least one potential-jump barrier or surface barrier the potential barriers being only of the PN heterojunction type
    • H01L31/0745Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof adapted as photovoltaic [PV] conversion devices characterised by at least one potential-jump barrier or surface barrier the potential barriers being only of the PN heterojunction type comprising a AIVBIV heterojunction, e.g. Si/Ge, SiGe/Si or Si/SiC solar cells
    • H01L31/0747Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof adapted as photovoltaic [PV] conversion devices characterised by at least one potential-jump barrier or surface barrier the potential barriers being only of the PN heterojunction type comprising a AIVBIV heterojunction, e.g. Si/Ge, SiGe/Si or Si/SiC solar cells comprising a heterojunction of crystalline and amorphous materials, e.g. heterojunction with intrinsic thin layer or HIT® solar cells; solar cells
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L31/00Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof
    • H01L31/18Processes or apparatus specially adapted for the manufacture or treatment of these devices or of parts thereof
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L31/00Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof
    • H01L31/18Processes or apparatus specially adapted for the manufacture or treatment of these devices or of parts thereof
    • H01L31/186Particular post-treatment for the devices, e.g. annealing, impurity gettering, short-circuit elimination, recrystallisation
    • H01L31/1868Passivation
    • YGENERAL 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
    • Y02TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02EREDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E10/00Energy generation through renewable energy sources
    • Y02E10/50Photovoltaic [PV] energy
    • YGENERAL 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
    • Y02TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02EREDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E10/00Energy generation through renewable energy sources
    • Y02E10/50Photovoltaic [PV] energy
    • Y02E10/547Monocrystalline silicon PV cells

Abstract

本发明的实施方式的一例的太阳能电池(10)包括:n型晶体硅衬底(11);和在该衬底的受光面上形成的、具有载流子生成功能的钝化层(20)。n型晶体硅衬底(11)在与钝化层(20)的界面附近具有掺杂成与该衬底相同导电型的、掺杂剂浓度为1×1017cm‑3以上的掺杂层。掺杂层中的掺杂剂浓度的平均值为1×1017cm‑3~1×1020cm‑3,掺杂层的厚度为200nm以下。

Description

太阳能电池
技术领域
本发明涉及太阳能电池。
背景技术
在具有晶体硅衬底的太阳能电池中,该衬底的受光面侧表面(受光面)的光生载流子的复合对输出造成很大影响。因此,在晶体硅衬底的受光面上形成钝化层。例如,在专利文献1中公开了一种太阳能电池,在n型单晶硅衬底的背面侧形成有p侧电极和n侧电极,作为在硅衬底的受光面上形成的钝化层具有非晶硅层。
现有技术文献
专利文献
专利文献1:国际公开第2012/132615号
发明内容
发明要解决的课题
即使在设置有钝化层的情况下,也不能够实现对在与晶体硅衬底的界面发生的光生载流子的复合的完全抑制,要求进一步抑制复合。
用于解决课题的方法
本发明的一个方式的太阳能电池包括:晶体硅衬底;和在晶体硅衬底的受光面上形成的、具有载流子生成功能的钝化层,晶体硅衬底在与钝化层的界面附近具有掺杂成与该衬底相同的导电型的、掺杂剂浓度为1×1017cm-3以上的掺杂层,掺杂层的掺杂剂浓度的平均值为1×1017cm-3~1×1020cm-3,掺杂层的厚度为200nm以下。
发明的效果
根据本发明的一个方式的太阳能电池,能够抑制晶体硅衬底的受光面中的光生载流子的复合,提高输出。
附图说明
图1是实施方式的一例的太阳能电池的截面图。
图2是表示在实施方式的一例的太阳能电池中,n+层的掺杂剂浓度与输出相对值的关系的图。
图3是表示在实施方式的一例的太阳能电池中,n+层的厚度与输出相对值的关系的图。
图4是实施方式的另一例的太阳能电池的截面图。
具体实施方式
本发明的一个方式的太阳能电池中,晶体硅衬底在与钝化层的界面附近具有掺杂成与该衬底相同的导电型的特定的掺杂层。如上所述,在设置有钝化层时,在与晶体硅衬底的界面也会由于各种原因而产生成为复合能级的缺陷,产生的光生载流子在该界面复合。本发明的发明者们关注钝化层具有载流子生成功能的点。发现通过在晶体硅衬底的与钝化层的界面附近设置上述掺杂层,能够抑制由钝化层生成的光生载流子的复合,提高太阳能电池的输出。
以下,参照附图详细说明实施方式的一个例子。
实施方式的说明中参照的附图是示意性记载的,附图中描绘的构成要素的尺寸比率等有时与实物不同。应该参照以下的说明判断具体的尺寸比例等。关于本说明书中“大致**”的记载,举出大致整个区域为例进行说明的话,整个区域当然也包括认为是实质上的整个区域的情况。
在实施方式的说明中,作为晶体硅衬底例示n型晶体硅衬底。在使用n型晶体硅衬底时,掺杂层应用掺杂成n型的n+层。另外,晶体硅衬底也可以是p型晶体硅衬底。此时,掺杂层应用掺杂成p型的p+层。
图1是表示实施方式的一例的太阳能电池10的截面图。
如图1所示,太阳能电池10包括n型晶体硅衬底11和在该衬底的受光面上形成的钝化层20。钝化层20是除了抑制n型晶体硅衬底11的受光面中的光生载流子的复合的钝化功能之外,还具有载流子生成功能的光发电层。太阳能电池10包括在n型晶体硅衬底11的背面上形成的p型半导体层12和n型半导体层13。p型半导体层12和n型半导体层13的一部分彼此重叠,在各层之间设置有绝缘层14,详情后述。
n型晶体硅衬底11(太阳能电池10)的“受光面”是指光主要入射(超过50%~100%)的面,“背面”是指与受光面相反侧的面。本实施方式中,入射至n型晶体硅衬底11的光的大致全部从受光面入射。
太阳能电池10包括:在p型半导体层12上形成的透明导电层15和集电极16(以下称为“p侧电极”);和在n型半导体层13上形成的透明导电层17和集电极18(以下称为“n侧电极”)。p侧电极和n侧电极彼此不接触而电分离。即,太阳能电池10包括仅在n型晶体硅衬底11的背面侧形成的一对电极。在n型晶体硅衬底11、钝化层20产生的空穴被p侧电极收集,电子被n侧电极收集。
太阳能电池10也可以在钝化层20上具有保护层(未图示)。保护层例如抑制钝化层20的损伤,且抑制光的反射。保护层优选由光透过性高的材料构成,由氧化硅(SiO2)、氮化硅(SiN)、或氮氧化硅(SiON)等构成是合适的。
n型晶体硅衬底11可以是n型多晶硅衬底,但优选是n型单晶硅衬底。n型晶体硅衬底11在与钝化层20的界面附近具有被掺杂成n型的、掺杂剂浓度为1×1017cm-3以上的n+层21。n+层21中的掺杂剂浓度的平均值为1×1017cm-3~1×1020cm-3,n+层21的厚度为200nm以下,详情后述。n型晶体硅衬底11的n+层21以外的区域中的掺杂剂浓度的平均值例如为1×1014cm-3~5×1016cm-3。n型晶体硅衬底11的厚度例如为50μm~300μm。
在n型晶体硅衬底11的表面,优选形成有纹理结构(未图示)。纹理结构是用于抑制表面反射而增大n型晶体硅衬底11的光吸收量的表面凹凸结构,例如仅形成于受光面,或者形成于受光面和背面这两者。纹理结构能够通过使用碱性溶液对单晶硅衬底的(100)面进行各向异性蚀刻而形成,在单晶硅衬底的表面形成使(111)面为斜面的金字塔形状的凹凸结构。纹理结构的凹凸的高度例如为1μm~15μm。
p型半导体层12和n型半导体层13均层叠在n型晶体硅衬底11的背面上,在该背面上分别形成p型区域和n型区域。p型区域的面积优选形成得比n型区域的面积大。p型区域和n型区域例如在一个方向上交替配置,以彼此啮合的俯视梳齿状图案形成。图1所示的例子中,p型半导体层12的一部分重叠在n型半导体层13的一部分之上,在n型晶体硅衬底11的背面上没有间隙地形成有各半导体层(p型区域、n型区域)。在p型半导体层12和n型半导体层13重叠的部分设置有绝缘层14。绝缘层14例如由氧化硅、氮化硅或氮氧化硅等构成。
p型半导体层12优选至少包括p型氢化非晶硅层(p型a-Si:H),特别优选具有i型氢化非晶硅层(i型a-Si:H)和p型氢化非晶硅层的层叠结构。p型半导体层12的优选的一个例子是,在n型晶体硅衬底11的背面层叠i型氢化非晶硅层,在i型氢化非晶硅层上层叠p型氢化非晶硅层。
n型半导体层13优选至少包括n型氢化非晶硅层(n型a-Si:H),特别优选具有i型氢化非晶硅层(i型a-Si:H)和n型氢化非晶硅层的层叠结构。n型半导体层13的优选的一个例子是,在n型晶体硅衬底11的背面层叠i型氢化非晶硅层,在i型氢化非晶硅层上层叠n型氢化非晶硅层。
i型a-Si:H层能够使用将硅烷气体(SiH4)以氢气(H2)稀释了的原料气体由化学气相沉积法(CVD)成膜。在p型a-Si:H层的成膜中,使用在硅烷中添加乙硼烷(B2H6)进行了氢气稀释的原料气体。在n型a-Si:H层的成膜中,使用代替乙硼烷而含有磷化氢(PH3)的原料气体。另外,各半导体层的成膜法没有特别限定。
透明导电层15、17在与绝缘层14对应的位置彼此分离。透明导电层15、17例如由在氧化铟(In2O3)、氧化锌(ZnO)等金属氧化物中掺杂有锡(Sn)、锑(Sb)等的透明导电性氧化物构成。透明导电层15、17的厚度优选为30nm~500nm,特别优选为50nm~200nm。
集电极16、18分别形成在透明导电层15、17上。集电极16、18可以使用导电性膏形成,但优选由电解镀形成。集电极16、18例如由镍(Ni)、铜(Cu)、银(Ag)等金属构成,可以是Ni层和Cu层的层叠结构,为了提高耐蚀性也可以在最靠表面的位置具有锡(Sn)层。集电极16、18的厚度优选为0.1μm~5μm,特别优选为0.5μm~2μm。
钝化层20例如在n型晶体硅衬底11的受光面的大致整个区域形成。钝化层20如上所述具有钝化功能和载流子生成功能。本实施方式中,在钝化层20产生的光生载流子(空穴和电子)向n型晶体硅衬底11的背面侧移动,被在背面上形成的p侧电极和n侧电极收集。钝化层20的厚度优选为5nm~100nm,更优选为10nm~80nm。
钝化层20优选主要成分是非晶或微晶的硅、或碳化硅,具体地说,优选是包括选自下述(1)~(8)的材料的层。钝化层20可以含有赋予与衬底相同的导电型的元素。钝化层20优选具有下述(1)的结构。
(1)i型a-Si:H
(2)n型a-Si:H
(3)i型氢化非晶碳化硅(i型a-SiC:H)
(4)n型a-SiC:H
(5)i型或n型a-Si:H和高浓度的n型a-Si:H的层叠体(i型或n型a-Si:H/高浓度的n型a-Si:H的层叠体)
(6)i型或n型a-Si:H/高浓度的n型氢化微晶硅(n型μc-Si:H)的层叠体
(7)i型或n型a-SiC:H/高浓度的n型a-Si:H的层叠体
(8)i型或n型a-SiC:H/高浓度的n型μc-Si:H的层叠体
此处关于“高浓度”,以“n型a-Si:H/高浓度的n型a-Si:H的层叠体”为例进行说明,是指与前者相比,后者的掺杂剂浓度较高。即,该记载意味着层叠有掺杂剂量不同的2个层的结构。
n+层21通过将n型晶体硅衬底11的与钝化层20的界面附近掺杂成n型而形成。n+层21是掺杂剂浓度为1×1017cm-3以上的区域,从与钝化层20的界面、即n型晶体硅衬底11的受光面起以200nm以下的厚度形成。换言之,在n型晶体硅衬底11中,仅在从受光面起的200nm以下的厚度范围,存在掺杂剂浓度为1×1017cm-3以上的区域。
n+层21中的掺杂剂浓度的平均值是1×1017cm-3~1×1020cm-3。只要掺杂剂浓度的平均值处于该范围内,则在n+层21的一部分中存在掺杂剂浓度超过1×1020cm-3的区域也是可以的,优选n+层21中的掺杂剂浓度的最大值为1×1020cm-3以下。n+层21例如可以具有从n型晶体硅衬底11的受光面起离得越远则掺杂剂浓度越低的浓度梯度,也可以在整个层具有大致均匀的掺杂剂浓度。
n+层21的掺杂剂浓度能够通过对形成有凹凸结构的n型晶体硅衬底11的表面用SIMS(Secondary Ion Mass Spectrometry,二次离子质谱分析法)测定得到,也能够由下述方法容易地测定得到。具体地说,形成在没有形成凹凸结构的、单晶硅衬底的平坦表面形成的高浓度的n型层,用SIMS测定高浓度的n型层的掺杂剂浓度。在对形成有凹凸结构的n型晶体硅衬底11的掺杂和对单晶硅衬底的平坦表面的掺杂在相同条件下进行时,能够推测n+层21的掺杂剂浓度与在平坦表面形成的高浓度的n型层的掺杂剂浓度相等。一边将单晶硅衬底的表面一点一点地切削,一边在距离晶体硅衬底的表面深度不同的多个地点测定掺杂剂浓度,而得到n+层21中所含的多个地点的掺杂剂浓度。
上述方法所得的掺杂剂浓度变为低于1×1017cm-3时的从单晶硅衬底的表面起的深度为n+层21的厚度。通过使从晶体硅衬底的表面起到n+层21的厚度为止的多个地点的掺杂剂浓度平均化,求得n+层21中的掺杂剂浓度的平均值。
n+层21使用例如热扩散法、等离子体掺杂法、或外延生长法等形成。在使用热扩散法或等离子体掺杂法时,形成在n型晶体硅衬底11的受光面处掺杂剂浓度最高、随着离开受光面而浓度逐渐变低的浓度梯度。例如,以从n型晶体硅衬底11的受光面起的200nm的厚度范围的掺杂剂浓度为1×1017cm-3以下的方式,从n型晶体硅衬底11的受光面掺杂磷(P)而形成n+层21。在使用外延生长法时,例如与使用热扩散法时相比,能够在n+层21的边界位置使掺杂剂浓度急剧上升,而且容易在n+层21的整体使掺杂剂浓度均匀化。
图2是表示n+层21的掺杂剂浓度与太阳能电池10的输出相对值的关系的图。图2所示的关系是n+层21的厚度为10nm、n+层21整体的掺杂剂浓度均匀时的实验结果。输出相对值是以不具有n+层21的太阳能电池的输出为1时的值(图3中也是同样的)。图3是表示n+层21的厚度与太阳能电池10的输出相对值的关系的图。图3所示的关系是n+层21的掺杂剂浓度为1×1019cm-3(层整体中均匀)时的实验结果。
如图2所示,n+层21的掺杂剂浓度(平均值)为1×1017cm-3~1×1020cm-3时,太阳能电池10的输出大幅提高。n+层21的掺杂剂浓度的平均值低于1×1017cm-3时不能够充分抑制上述界面缺陷引起的复合,n+层21的形成带来的效果不易实现。另一方面,当掺杂剂浓度的平均值超过1×1020cm-3时,例如在n+层21内由钝化层20产生的空穴的复合容易发生,反而输出变低。n+层21的掺杂剂浓度与输出相对值的关系在n+层21的厚度为5nm~100nm程度时与图2所示的关系是相同的,当厚度超过100nm时存在最佳的掺杂剂浓度变低的倾向。n+层21的掺杂剂浓度的平均值优选是1×1018cm-3~2×1019cm-3
如图3所示,n+层21的厚度为200nm以下时,太阳能电池10的输出大幅提高。当n+层21的厚度超过200nm时,例如在n+层21内由钝化层20产生的空穴的复合容易发生,反而输出变低。n+层21的厚度与输出相对值的关系在n+层21的掺杂剂浓度的平均值为1×1018cm-3~2×1019cm-3程度时与图3所示的关系是相同的,当浓度超过2×1019cm-3时存在最佳的厚度变小的倾向。n+层21的厚度优选是2nm~200nm,特别优选是5nm~100nm。当n+层21的厚度低于2nm时,不能够充分抑制上述界面缺陷引起的复合,n+层21的形成带来的效果不易实现。
n+层21特别优选掺杂剂浓度的平均值为1×1018cm-3~2×1019cm-3,且n+层21中掺杂剂浓度为1×1018cm-3~2×1019cm-3的区域的厚度为5nm~100nm。n+层21的优选的具体例是,整体的厚度为5nm~200nm、或5nm~100nm,掺杂剂浓度为1×1018cm-3~2×1019cm-3的区域的厚度为5nm~100nm。
根据具有上述结构的太阳能电池10,能够抑制n型晶体硅衬底11与钝化层20的界面的光生载流子的复合,进一步提高输出。即,利用n+层21能够抑制由在该界面产生的缺陷引起的光生载流子的复合,减小由于复合引起的输出损失。
从抑制n型晶体硅衬底11与钝化层20的界面处的光生载流子的复合的观点出发,钝化层20优选包括赋予与n型晶体硅衬底11相同的导电型的元素。由此,能够从钝化层20向n型晶体硅衬底11供给电子,界面的电子浓度增加,使得由缺陷引起的复合率下降。但是需要注意的是,由于掺杂,在氢化非晶硅层的膜中缺陷会增加,因此当掺杂量过多时,载流子生成功能会减小。
钝化层20包括赋予与n型晶体硅衬底11相同的导电型的元素时,钝化层20的主要成分优选是微晶硅。由此,能够使钝化层20的掺杂剂的活性化率较高。详细地说,与n型氢化非晶硅相比,n型氢化微晶硅的掺杂剂活性化率更高,因此在掺杂量相同时,n型氢化微晶硅能够将更多的电子供给至n型晶体硅衬底11。由此,能够增加n型晶体硅衬底11与钝化层20的界面的电子浓度,能够减小缺陷处的复合。
图4是表示实施方式的另一例的太阳能电池30的截面图。
如图4所示,太阳能电池30与太阳能电池10的共同点是,包括n型晶体硅衬底31,和在该衬底的受光面上形成的具有载流子生成功能的钝化层40。n型晶体硅衬底31与太阳能电池10同样,优选是n型单晶硅衬底,在与钝化层40的界面附近具有掺杂成n型的n+层41。另一方面,太阳能电池30包括:在n型晶体硅衬底11的受光面侧形成的受光面电极;和在n型晶体硅衬底11的背面侧形成的背面电极,这一点与电极仅形成在背面侧的太阳能电池10不同。
受光面电极和背面电极分别具有透明导电层33、35和在该透明导电层上形成的集电极34、36。透明导电层33、35与太阳能电池10的透明导电层15、17同样,由透明导电性氧化物构成。集电极34、36例如通过用包括多个副栅线部和2个或3个主栅线部的图案对导电性膏进行丝网印刷而形成。集电极36优选形成为面积比集电极34大,集电极36的副栅线部形成得比集电极34的副栅线部多。此外,集电极34形成得比集电极36厚。另外,电极的结构没有特别限定,例如作为背面电极的集电极,可以在透明导电层35上的大致整个区域形成金属层。
太阳能电池30包括在n型晶体硅衬底31的背面上形成的p型半导体层32。p型半导体层32例如在n型晶体硅衬底31的背面的大致整个区域形成,在p型半导体层32上的大致整个区域形成透明导电层35。作为p型半导体层32,能够使用与太阳能电池10的p型半导体层12相同的材料。在n型晶体硅衬底31的受光面上形成钝化层40。钝化层40例如在n型晶体硅衬底31的受光面的大致整个区域形成,在钝化层40上的大致整个区域形成透明导电层35。
钝化层40与钝化层20同样,优选是包括选自上述(1)~(8)的材料的层。钝化层40从减小与透明导电层33的接触电阻等的观点出发,优选具有选自上述(5)~(8)的层叠结构,优选与透明导电层33的接触面由n型μc-Si:H构成。
n+层41与n+层21同样是掺杂剂浓度为1×1017/cc以上的区域,以从n型晶体硅衬底31的受光面起200nm以下的厚度形成。n+层41的掺杂剂浓度的平均值是1×1017/cc~1×1020/cc,优选是1×1018/cc~2×1019/cc。n+层41的厚度优选是2nm~200nm,特别优选是5nm~100nm。n+层41特别优选的是,掺杂剂浓度的平均值为1×1018cm-3~2×1019cm-3,且n+层41中掺杂剂浓度为1×1018cm-3~2×1019cm-3的区域的厚度为5nm~100nm。
太阳能电池30与太阳能电池10同样,能够抑制在n型晶体硅衬底31与钝化层40的界面中的光生载流子的复合,能够进一步提高输出。
另外,在本实施方式的另一例中,n+层41配置在n型晶体硅衬底31的受光面,但也可以将n+层41配置在n型晶体硅衬底31的背面。在光也会入射到与光主要入射的面相反的一侧的面而用于发电时,能够采用将n+层41配置在n型晶体硅衬底31的背面的结构。此时,在n型晶体硅衬底31的受光面配置p型半导体层32而形成pn结。在本实施方式的另一例中,能够在与形成有pn结的面相反的一侧的n型晶体硅衬底31的表面形成n+层41,提高入射至形成有n+层41的n型晶体硅衬底31的表面的光对发电的贡献。
附图标记的说明
10、30 太阳能电池
11、31 n型晶体硅衬底
12、32 p型半导体层
13 n型半导体层
14 绝缘层
15、17、33、35 透明导电层
16、18、34、36 集电极
20、40 钝化层
21、41 n+层。

Claims (7)

1.一种太阳能电池,其特征在于,包括:
晶体硅衬底;
形成在所述晶体硅衬底的受光面上的、具有载流子生成功能的钝化层;
经由第1透明导电层设置在所述钝化层上的、包含多个副栅线电极的第1金属电极;和
经由第2透明导电层形成在与所述受光面相对的背面上的第2金属电极,
所述晶体硅衬底在与所述钝化层的界面附近具有掺杂成与该衬底相同导电型的、掺杂剂浓度的平均值为1×1018~2×1019cm-3的掺杂层,
所述晶体硅衬底是n型晶体硅衬底,所述掺杂层是所述n型晶体硅衬底的表面掺杂成n型的n+层,
所述晶体硅衬底的所述掺杂层以外的区域中的掺杂剂浓度的平均值为1×1014cm-3~5×1016cm-3
所述掺杂层的所述掺杂剂浓度,具有随着离开所述受光面而掺杂剂浓度逐渐变低的浓度梯度,
所述掺杂层的厚度为5nm~100nm,
所述第1电极的形成面积比所述第2电极的形成面积小。
2.如权利要求1所述的太阳能电池,其特征在于,包括:
形成在所述晶体硅衬底的受光面侧的受光面电极;和
形成在所述晶体硅衬底的背面侧的背面电极。
3.如权利要求1所述的太阳能电池,其特征在于:
所述钝化层的主要成分是非晶或微晶的硅、或碳化硅。
4.如权利要求3所述的太阳能电池,其特征在于:
所述钝化层包括赋予与所述晶体硅衬底相同的导电型的元素。
5.如权利要求3所述的太阳能电池,其特征在于:
所述钝化层包括下述各层的任一种:i型a-Si:H;n型a-Si:H;i型a-SiC:H;n型a-SiC:H;i型或n型a-Si:H/高浓度的n型a-Si:H的层叠体;i型或n型a-Si:H/高浓度的n型μc-Si:H的层叠体;i型或n型a-SiC:H/高浓度的n型a-Si:H的层叠体;或者,i型或n型a-SiC:H/高浓度的n型μc-Si:H的层叠体。
6.如权利要求2所述的太阳能电池,其特征在于:
所述钝化层是包括下述层叠体的层:i型或n型a-Si:H/高浓度的n型a-Si:H的层叠体;i型或n型a-Si:H/高浓度的n型μc-Si:H的层叠体;i型或n型a-SiC:H/高浓度的n型a-Si:H的层叠体;或者,i型或n型a-SiC:H/高浓度的n型μc-Si:H的层叠体。
7.如权利要求6所述的太阳能电池,其特征在于:
所述受光面电极具有透明导电层,
所述钝化层的与所述透明导电层的接触面由所述n型μc-Si:H构成。
CN201680031268.9A 2015-05-29 2016-05-09 太阳能电池 Active CN107735866B (zh)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
JP2015-109839 2015-05-29
JP2015109839 2015-05-29
PCT/JP2016/002267 WO2016194301A1 (ja) 2015-05-29 2016-05-09 太陽電池

Publications (2)

Publication Number Publication Date
CN107735866A CN107735866A (zh) 2018-02-23
CN107735866B true CN107735866B (zh) 2021-05-14

Family

ID=57440807

Family Applications (1)

Application Number Title Priority Date Filing Date
CN201680031268.9A Active CN107735866B (zh) 2015-05-29 2016-05-09 太阳能电池

Country Status (4)

Country Link
US (1) US20180076340A1 (zh)
JP (2) JP6452011B2 (zh)
CN (1) CN107735866B (zh)
WO (1) WO2016194301A1 (zh)

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US11302829B2 (en) 2017-03-29 2022-04-12 Kaneka Corporation Photovoltaic device and method for manufacturing photovoltaic device
WO2018180227A1 (ja) * 2017-03-31 2018-10-04 パナソニック株式会社 太陽電池セル
JP7346050B2 (ja) 2019-03-26 2023-09-19 パナソニックホールディングス株式会社 太陽電池セルおよび太陽電池モジュール
JP2021044384A (ja) * 2019-09-11 2021-03-18 パナソニック株式会社 太陽電池セル

Family Cites Families (21)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5467778A (en) * 1977-11-10 1979-05-31 Toshiba Corp Production of semiconductor device
JPH11312814A (ja) * 1998-04-28 1999-11-09 Toyota Motor Corp 太陽電池素子
JP2004214442A (ja) * 2003-01-06 2004-07-29 Sanyo Electric Co Ltd 光起電力装置およびその製造方法
US20080173347A1 (en) * 2007-01-23 2008-07-24 General Electric Company Method And Apparatus For A Semiconductor Structure
WO2010046284A1 (en) * 2008-10-23 2010-04-29 Applied Materials, Inc. Semiconductor device manufacturing method, semiconductor device and semiconductor device manufacturing installation
JP2010123859A (ja) * 2008-11-21 2010-06-03 Kyocera Corp 太陽電池素子および太陽電池素子の製造方法
JP5174635B2 (ja) * 2008-11-28 2013-04-03 京セラ株式会社 太陽電池素子
US9318644B2 (en) * 2009-05-05 2016-04-19 Solexel, Inc. Ion implantation and annealing for thin film crystalline solar cells
US8546685B2 (en) * 2009-07-03 2013-10-01 Kaneka Corporation Crystalline silicon based solar cell and method for manufacturing thereof
US20130167915A1 (en) * 2009-12-09 2013-07-04 Solexel, Inc. High-efficiency photovoltaic back-contact solar cell structures and manufacturing methods using three-dimensional semiconductor absorbers
JP5484950B2 (ja) * 2010-02-23 2014-05-07 三洋電機株式会社 太陽電池
US9076909B2 (en) * 2010-06-18 2015-07-07 Semiconductor Energy Laboratory Co., Ltd. Photoelectric conversion device and method for manufacturing the same
US20120312361A1 (en) * 2011-06-08 2012-12-13 International Business Machines Corporation Emitter structure and fabrication method for silicon heterojunction solar cell
KR20130050721A (ko) * 2011-11-08 2013-05-16 삼성에스디아이 주식회사 태양 전지
JP5868290B2 (ja) * 2012-08-23 2016-02-24 三菱電機株式会社 光起電力装置およびその製造方法
JP5889163B2 (ja) * 2012-11-02 2016-03-22 三菱電機株式会社 光起電力装置およびその製造方法、光起電力モジュール
KR101925928B1 (ko) * 2013-01-21 2018-12-06 엘지전자 주식회사 태양 전지 및 그의 제조 방법
US9640699B2 (en) * 2013-02-08 2017-05-02 International Business Machines Corporation Interdigitated back contact heterojunction photovoltaic device
JP2015026666A (ja) * 2013-07-25 2015-02-05 日立化成株式会社 両面受光型太陽電池素子、その製造方法及び両面受光型太陽電池モジュール
US9105769B2 (en) * 2013-09-12 2015-08-11 International Business Machines Corporation Shallow junction photovoltaic devices
US11031516B2 (en) * 2013-10-25 2021-06-08 Sharp Kabushiki Kaisha Photoelectric conversion element, photoelectric conversion module, and solar photovoltaic power generation system

Also Published As

Publication number Publication date
JP2019033298A (ja) 2019-02-28
US20180076340A1 (en) 2018-03-15
JP6452011B2 (ja) 2019-01-16
WO2016194301A1 (ja) 2016-12-08
JP6893331B2 (ja) 2021-06-23
CN107735866A (zh) 2018-02-23
JPWO2016194301A1 (ja) 2018-03-01

Similar Documents

Publication Publication Date Title
JP5546616B2 (ja) トンネル酸化物を有する後面接合太陽電池
US20140283902A1 (en) Back junction solar cell with tunnel oxide
US10084107B2 (en) Transparent conducting oxide for photovoltaic devices
AU2013309484B2 (en) Tunneling-junction solar cell with shallow counter doping layer in the substrate
US8686283B2 (en) Solar cell with oxide tunneling junctions
US20140102524A1 (en) Novel electron collectors for silicon photovoltaic cells
CN110707159A (zh) 一种正背面全面积接触钝化的p型晶硅太阳电池及其制备方法
JP6893331B2 (ja) 太陽電池
US20140238476A1 (en) Photoelectric conversion device and manufacturing method thereof, and photoelectric conversion module
US20100243042A1 (en) High-efficiency photovoltaic cells
JP5755372B2 (ja) 光発電装置
KR100990864B1 (ko) 태양전지 및 그 제조 방법
JP6976101B2 (ja) 結晶シリコン系太陽電池
JPWO2013179529A1 (ja) 太陽電池
JP2020167238A (ja) 太陽電池セルおよび太陽電池モジュール
JP2024503613A (ja) 太陽電池
US11430904B2 (en) Solar cell and method of manufacturing solar cell
US20110155229A1 (en) Solar cell and method for manufacturing the same
KR20130061346A (ko) 태양전지 및 그 제조방법
JP2012212769A (ja) 太陽電池素子
WO2018061769A1 (ja) 太陽電池セルおよび太陽電池セルの製造方法
JP2010283162A (ja) 太陽電池及びその製造方法
KR20190125754A (ko) 그라파이트 기판 및 그래핀을 이용한 태양 전지 및 이의 제조 방법
CN111755537A (zh) 太阳能单电池和太阳能电池组件

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination
GR01 Patent grant
GR01 Patent grant