201242053 六、發明說明： 【發明所屬之技術領域】 本發明係關於一種背面接合型的太陽能電池。 【先前技術】 以往，已知有一種在太陽能電池的背面侧配置有p型 和η型半導體區域的所謂背面接合型的太陽能電池。例如， 下述專利文獻1中，記載有一種在背面上形成有相互間插 合的梳齒狀的Ρ側電極和η侧電極的太陽能電池，以作為 背面接合型的太陽能電池。該背面接合型的太陽能電池， 不需要在受光面側設置電極。因此，在背面接合型的太陽 能電池中，能夠提高光的受光效率。從而能夠實現更高的 光電變換效率。 (先前技術文獻） 專利文獻1 :日本特開2010-80887號公報 【發明内容】 (發明所欲解決之課題） 但是，近年來，對於太陽能電池提高光電變換效率的 要求更進一步提高。 本發明係鑑於該點而研創者，其目的在於提供一種具 有經改善之光電變換效率的太陽能電池。 (解決課題之手段） 本發明的太陽能電池係具備太陽能電池基板.、一導電 型側電極、及另一導電型側電極。太陽能電池基板係在一 主面具有一導電型表面及另一導電型表面。一導電型侧電 ：323796 4 201242053 極係配置在一導電型表面之上。另一導電型侧電極係配置 在另一導電型表面之上。另一導電型側電極具有複數個另 一導電型側指狀電極部及另一導電型側匯流條部。複數個 另一導電型側指狀電極部係分別從第一方向的一侧朝另一 側延伸。複數個另一導電型側指狀電極部係沿著與第一方 向垂直的第二方向排列。另一導電型侧匯流條部係將複數 個另一導電型侧指狀電極部予以電性連接。一導電型側電 極具有複數個梳齒狀電極部。複數個梳齒狀電極部係沿著 第二方向排列。複數個梳齒狀電極部係分別具有複數個一 導電型側指狀電極部及一導電型側匯流條部。複數個一導 t型側指狀電極部係分別在第二方向相鄰的另一導電型側 指狀電極部之間，從第一方向的另一侧朝一側延伸。一導 電型側匯流條部係將複數個一導電型侧指狀電極部予以電 性連接。複數個另一導電型側指狀電極部包括：位於在第 二方向相鄰的梳齒狀電極部之間的另一導電型側指狀電極 部。位於相鄰的梳齒狀電極部之間的另一導電型側指狀電 極部的前端部係位於相鄰的梳齒狀電極部的一導電型側匯 流條部之間。 根據本發明，能夠提供一種具有經改善的光電變換效 率的太陽能電池。 【實施方式】 以下，說明實施本發明的較佳形態式的一例。但是， 以下的實施形態只是單純的例示。本發明不限於以下的實 施形態。 323796 5 201242053 . \ 此外，在實施形態等中參照的各圖式中，具有實質上 ,相1同的功能的構件係標注相同的符號。此外，在實施形態 等中參照的圖式是示意性者，會有描繪在圖式上的物體的 尺寸比例等與現實物體的尺寸比解不同的情況。在圖式 彼此之間，也會有物體的尺寸比例等不同的情況。具體的 物體的尺寸比例等，應參考以下的說明來判斷。 (第1實施形態） 第1圖係本實施形態的太陽能電池1的背面的概要平 面圖。在該第1圖及下述第2圖至第7圖中為了容易理 解電極的形狀而標有陰影線’但在第i圖至第7圖中標有 陰影線的區域並不是剖面。 7 太陽能電池1係所謂背面接合型的太陽能電池。太陽 能電池1具有太陽能電池基板10。太陽能電池基板1〇是 藉由受光而生成電子、電洞等載子的構件。太陽能電池基 板10具有受光面和背面l〇a。在背面1〇a上露出有η型表 面10an、及ρ型表面i〇ap。 太陽能電池基板10也可以是包括：由具有一導電型 的結晶性半導體所形成的基板；及配置在該半導體基板的 责面之上的ρ型非晶半導體層和n型非晶半導體層。該情 况下’ P型表面l〇ap係由ρ型非晶半導體層的表面所構 成。η型表面l〇an係由n型非晶半導體層的表面所構成。 其中，P型非晶半導體層例如能夠由含有氣的p型的 非晶石夕所形成。η型非晶半導體層例如能夠由含有氯的^ 型的非晶石夕所形成。也可以在p型非晶半導體層和η型非 323796 , 201242053 •晶1半導體層的各個與結晶性半導體層之間，配置有厚度為 ‘ 實質上無助於發電之程度的i型非晶半導體層。i型^晶 • 半導體層例如能夠由含有氫的i型的非晶矽所形成。 此外，太陽能電池基板10亦可以由半導體基板所構 成’該半導體基板係具有一導電型、且在背面側設置擴散 有p型摻雜劑的P型摻雜劑擴散區域及擴散有η型摻雜劑 的η型摻雜劑擴散區域的半導體基板所構成。在該情況 下，Ρ型表面l〇ap係由ρ型摻雜劑擴散區域的表面所構 成。η型表面1 〇an係由n型摻雜劑擴散區域的表面所構成。 半導體基板的厚度較佳為2mm以下。半導體基板的厚 度的下限較佳為〇.〇lmm。結晶性半導體基板的電阻率較佳 為 0. lQcm 至 l〇〇Qcm。 以下’本實施形態中，針對太陽能電池基板具有η 塑的半導體基板、配置在半導體基板的背面之上的ρ型非 晶半導體層及η型非晶半導體層的例子進行說明。因此， 本實施形態中’一導電型是η型，電洞是少數載子。 在太陽能電池基板10的背面l〇a之上，配置有ρ侧 電極lip和η侧電極llr^p側電極llp係配置在p型表面 10ap之上。η側電極lln係配置在η型表面10an之上。 P側電極1 lp和η侧電極1 In的材質，只要是導電材 料就沒有特別限定。各個ρ侧電極11 ρ和η侧電極11 η， 例如能夠由銀、銅、鋁、鈦、鎳、鉻等金屬、或包含這些 金屬中的一種以上的合金、TC0(Transparent Conductive 〇xide，透明導電氧化物膜）等所形成。此外，各個ρ側電 323796 7 201242053 極lip和η侧電極1 In，例如還可以由上述金屬、合金、 T C 0所形成的複數個導電層的疊層體構成。各個p ^電極201242053 VI. Description of the Invention: [Technical Field of the Invention] The present invention relates to a back junction type solar cell. [Prior Art] Conventionally, a so-called back junction type solar cell in which p-type and n-type semiconductor regions are disposed on the back side of a solar cell has been known. For example, Patent Document 1 listed below discloses a solar cell in which a comb-shaped side electrode and an n-side electrode which are coupled to each other on the back surface are formed as a back surface bonding type solar cell. In the back junction type solar cell, it is not necessary to provide an electrode on the light receiving surface side. Therefore, in the back junction type solar cell, the light receiving efficiency of light can be improved. Thereby, higher photoelectric conversion efficiency can be achieved. (Problems to be Solved by the Invention) However, in recent years, the demand for improving the photoelectric conversion efficiency of solar cells has been further improved. The present invention has been made in view of this point, and an object thereof is to provide a solar cell having improved photoelectric conversion efficiency. (Means for Solving the Problem) The solar cell of the present invention includes a solar cell substrate, a conductive side electrode, and another conductive side electrode. The solar cell substrate has a conductive surface and another conductive surface in a main mask. A conductive side power: 323796 4 201242053 The pole system is placed on a conductive surface. Another conductive type side electrode is disposed on the other conductive type surface. The other conductive type side electrode has a plurality of other conductive type side finger electrode portions and another conductive type side bus bar portion. A plurality of other conductive side finger electrode portions extend from one side in the first direction to the other side, respectively. A plurality of other conductive side finger electrode portions are arranged in a second direction perpendicular to the first direction. The other conductive side bus bar portion electrically connects a plurality of other conductive type side finger electrodes. A conductive side electrode has a plurality of comb-shaped electrode portions. A plurality of comb-shaped electrode portions are arranged along the second direction. The plurality of comb-shaped electrode portions each have a plurality of conductive side finger electrodes and a conductive side bus bar. The plurality of t-type side finger electrode portions are respectively extended between the other side of the first direction and the other side between the other conductive type side finger portions adjacent in the second direction. A conductive side bus bar portion electrically connects a plurality of conductive side finger electrodes. The plurality of other conductive type side finger electrode portions include another conductive type side finger electrode portion located between the comb-shaped electrode portions adjacent in the second direction. The front end portion of the other conductive type side finger electrode portion located between the adjacent comb-shaped electrode portions is located between one of the conductive type side bus bar portions of the adjacent comb-shaped electrode portions. According to the present invention, it is possible to provide a solar cell having improved photoelectric conversion efficiency. [Embodiment] Hereinafter, an example of a preferred embodiment of the present invention will be described. However, the following embodiments are merely examples. The present invention is not limited to the following embodiments. 323796 5 201242053 . In addition, in the drawings referred to in the embodiments and the like, members having substantially the same functions are denoted by the same reference numerals. Further, the drawings referred to in the embodiment and the like are schematic, and the size ratio of the object drawn on the drawing or the like may be different from the size ratio of the real object. Between the drawings, there may be cases where the size ratio of the objects is different. The specific size ratio of the object, etc., should be judged by referring to the following instructions. (first embodiment) Fig. 1 is a schematic plan view showing the back surface of the solar cell 1 of the present embodiment. In the first drawing and the following Figs. 2 to 7, the hatched line is marked for easy understanding of the shape of the electrode, but the hatched area in the i-th to seventh figures is not a cross-section. 7 Solar cell 1 is a so-called back junction type solar cell. The solar cell 1 has a solar cell substrate 10. The solar cell substrate 1 is a member that generates carriers such as electrons and holes by receiving light. The solar cell substrate 10 has a light receiving surface and a rear surface 10a. An n-type surface 10an and a p-type surface i〇ap are exposed on the back surface 1〇a. The solar cell substrate 10 may include a substrate formed of a crystalline semiconductor having a conductivity type, and a p-type amorphous semiconductor layer and an n-type amorphous semiconductor layer disposed on the surface of the semiconductor substrate. In this case, the 'P-type surface l〇ap is composed of the surface of the p-type amorphous semiconductor layer. The n-type surface l〇an is composed of the surface of the n-type amorphous semiconductor layer. Among them, the P-type amorphous semiconductor layer can be formed, for example, from a p-type amorphous stone containing gas. The n-type amorphous semiconductor layer can be formed, for example, from a crystalline amorphous form containing chlorine. It is also possible to arrange an i-type amorphous semiconductor having a thickness of 'substantially no power generation' between the p-type amorphous semiconductor layer and the n-type non-323796, 201242053, and each of the crystalline semiconductor layers and the crystalline semiconductor layer. Floor. I-type crystal • The semiconductor layer can be formed, for example, of an i-type amorphous germanium containing hydrogen. Further, the solar cell substrate 10 may be composed of a semiconductor substrate having a conductivity type and a P-type dopant diffusion region in which a p-type dopant is diffused on the back side and diffused with n-type doping. The semiconductor substrate of the n-type dopant diffusion region of the agent is formed. In this case, the Ρ-type surface l〇ap is composed of the surface of the p-type dopant diffusion region. The n-type surface 1 〇an is composed of the surface of the n-type dopant diffusion region. The thickness of the semiconductor substrate is preferably 2 mm or less. The lower limit of the thickness of the semiconductor substrate is preferably 〇.〇lmm. The resistivity of the crystalline semiconductor substrate is preferably from 0. lQcm to l〇〇Qcm. In the following description, an example in which a solar cell substrate has a η plastic semiconductor substrate and a p-type amorphous semiconductor layer and an n-type amorphous semiconductor layer disposed on the back surface of the semiconductor substrate will be described. Therefore, in the present embodiment, the 'one conductivity type is an n type, and the hole is a minority carrier. On the back surface 10a of the solar cell substrate 10, the p-side electrode lip and the n-side electrode 11r-p side electrode 11p are disposed on the p-type surface 10ap. The n-side electrode 11n is disposed on the n-type surface 10an. The material of the P-side electrode 1 lp and the η-side electrode 1 In is not particularly limited as long as it is a conductive material. Each of the ρ-side electrode 11 ρ and the η-side electrode 11 η can be made of, for example, a metal such as silver, copper, aluminum, titanium, nickel, or chromium, or an alloy containing one or more of these metals, and TC0 (Transparent Conductive 〇xide). An oxide film or the like is formed. Further, each of the ρ side electric 323796 7 201242053 pole lip and the η side electrode 1 In may be composed of, for example, a laminate of a plurality of conductive layers formed of the above metal, alloy, and T C 0 . Each p ^ electrode
1]·ρ和η側電極lln例如能夠使用濺鍍法、蒸錢法、網版 印刷法或鍍覆法等形成。 V 本實施形態中，P侧電極Up係由一個梳齒狀電 構成。當^，本發明中，P侧電極11P也可以由複 齒狀電極所構成。P侧電極IIP具有作為1)側抨狀极 的複數個指狀電極部12p ’及作為p側匯流條::部 部13p。複數個指狀電極部I2p係分別從\方向的’机條 XI側直線狀地延伸。複數個指狀電極部12p係产\x2側朝 向垂直的y方向排列。 、X方 複數個指狀電極部12p係藉由匯流條部13 接。本實施形態中’匯流條部13p係配置在複 ^生連 極部12p的χ2側。匯流條部13iM系形成為直線狀固指狀電 本發明並不限於該構成。本發明中 钽是， 側指狀電極部予以電性連接，p侧匯流數個。 特別限定。P側匯流條部也可以不是直線狀。例1並沒有 流條部也可以具有電極塾及將該電極塾^’Ρ側匯 予以連接的複數個連接部。 9狀電極部 本實施形態中’ n側電極Un係被分離 =體而言，η側電極Un具有複數狀= 固電極 =電極Un中所包含的梳齒 ::部14。 至50,更佳為3至5。 妁數量較佳為2 複數個梳齒狀電極部 323796 係…方向排列。複數個 201242053 梳齒狀電極部14係分別與p側電極t i p相互間插人。 丄電極部U分別具有作“側指_ 電極部12n係沿著y方向^匯=部❿。複數個指狀 白少认七/万⑽列0複數個指狀電極部12n各 自在於y方向相鄰的指狀電極部砌之間， 側朝x2側直線狀地延伸。 白的xl 接。=ίΓ部，係藉由匯流條…^ U条部13讀、配置在複數個指狀電 =n的相。匯流條部…係形成為直…^ :明不限於該構成。本發明中，只要能夠將複數個“則 指狀電極部予以雷柯遠 接，n側匯流條部的形狀就沒有特 條部::二匯有=部也可以不是直線狀。例如，n侧匯流 予以連接的複數個連接部。 ⑨興順狀電極# 2方向相鄰的梳齒狀電極部14的匯流條部—之 B S距離較佳為0.0()1丽至_，更佳為G.Q()lmm至 4mm ° 電極部二方向相鄰的梳齒狀電極部14之間，配置有指狀 方_^ 複數個指狀電極部吻係、包括位於在乂 ==齒狀電極部14之間的指狀電極卿。該 曰狀電極部咖係比其他的指 部Upl的前踹邱尨， 电找口丨以P長。扣狀電極 的匯流侔部13 在7方向相鄰的梳齒狀電極部14 .St間。換言之，指狀__端係 方向到達匯流條部i3n的位置。指狀電極部咖的前 323796 9 201242053 端部係在y方向與 另外，本實施形態中=至少一部分相對向。 與匯流條部侧的端\狀電極部12pl的xl側前端 不限於該構成。指狀電極^㈣成齊平。但是’本發明 匯流條部W的X1側前端更lPl的Xl側前端係可位於比 螭更罪χ2側之位置，亦可亦可 ㈣向=只要與匯流條部 於^個心狀電極部12p及複數個指狀電極部I2n中位 7向之最外侧的指狀電極部係為指狀電極部l2p。^The 1]·ρ and η side electrodes 11n can be formed, for example, by a sputtering method, a steaming method, a screen printing method, a plating method, or the like. V In the present embodiment, the P-side electrode Up is constituted by one comb-shaped electric power. In the present invention, the P-side electrode 11P may also be composed of a complex-teeth electrode. The P-side electrode IIP has a plurality of finger electrode portions 12p' as 1) side ridge electrodes and a p-side bus bar: portion 13p. The plurality of finger electrode portions I2p extend linearly from the 'strip XI side of the \ direction, respectively. The plurality of finger electrode portions 12p are arranged on the \x2 side in the vertical y direction. The X-shaped plurality of finger electrode portions 12p are connected by the bus bar portion 13. In the present embodiment, the bus bar portion 13p is disposed on the side of the χ2 of the regenerative pole portion 12p. The bus bar portion 13iM is formed in a linear solid finger shape. The present invention is not limited to this configuration. In the present invention, the side finger electrode portions are electrically connected, and the p side side is confluent. Specially limited. The P-side bus bar portion may not be linear. In the example 1, the flow bar portion may have an electrode 塾 and a plurality of connection portions for connecting the electrode Ρ^' Ρ side. In the present embodiment, the n-side electrode Un is separated from the body. The n-side electrode Un has a complex number = the solid electrode = the comb-and-finished portion 14 included in the electrode Un. Up to 50, more preferably 3 to 5. The number of turns is preferably 2, and a plurality of comb-shaped electrode portions 323796 are arranged in the direction of . A plurality of 201242053 comb-shaped electrode portions 14 are interposed with the p-side electrodes t i p, respectively. Each of the 丄 electrode portions U has a side finger _ electrode portion 12n along the y direction = = = part ❿. A plurality of finger whites are less seven/10,000 (10) columns 0 plural finger electrodes 12n are each in the y direction Between the adjacent finger electrode portions, the side extends linearly toward the x2 side. The white xl is connected to the = , part, which is read by the bus bar ... ^ U bar 13 and arranged in a plurality of fingers = n The bus bar portion is formed in a straight line. It is not limited to this configuration. In the present invention, as long as a plurality of "the finger electrode portions can be connected to each other, the shape of the n-side bus bar portion is not Special section:: The second section has a part or it may not be linear. For example, the n-side bus is connected to a plurality of connections. The bus bar portion of the comb-shaped electrode portion 14 adjacent to the 2 direction is preferably 0.0 () 1 to _, more preferably GQ () 1 mm to 4 mm ° in the electrode direction Between the adjacent comb-shaped electrode portions 14, a plurality of finger-shaped electrode portions are disposed between the finger-shaped electrode portions 14 and include finger electrodes located between the 乂==tooth-shaped electrode portions 14. The braided electrode portion is longer than the other finger Upl. The bus bar portion 13 of the button electrode is between the comb-shaped electrode portions 14 and St adjacent in the seven directions. In other words, the finger __ end direction reaches the position of the bus bar portion i3n. The front portion of the finger electrode portion 323796 9 201242053 The end portion is in the y direction and, in the present embodiment, at least a portion is opposed to each other. The front end on the x1 side of the end electrode portion 12 pl on the side of the bus bar portion is not limited to this configuration. The finger electrode ^ (4) is flush. However, the front end of the X1 side of the bus bar portion W of the present invention may be located on the X1 side of the sin 2 side, or may be (4) direction = as long as the bus bar portion is in the heart electrode portion 12p. The finger electrode portions on the outermost side of the plurality of finger electrode portions I2n are referred to as the finger electrode portions 12p. ^
^ ^^^1； ；2" 及:复數個指狀電極部12n中位於y方向之最外侧的P 極部12p2。該指狀部12p2係在y方向與匯流條部^電 的至> 部分相對向。亦即，指狀電極部邮的前端 x方向到達匯流條部13η的位置。 ’、 另外，本實施形態中，指狀電極部12ρ2的xl侧前端 與匯流條部13η的xl側的端邊係形成齊平。但是，本發明 不限於該構成。指狀f極部12p2的χ1侧前端係可位於比 匯"it條。卩13η的xi側前端更靠χ2侧之位置，亦可位於比 匯流條部13η的xl側前端更靠χ1侧之位置。 但疋，如上述專利文獻1所述，由一個梳齒狀電極構 成n側電極和p侧電極的各個的情況下，難以充分改善光 電^1換效率。這可能是因為，在位於太陽能電池基板的η 侧電極的匯流條部之下的部分所產生之作為少數載子的電 323796 201242053 洞在被P側電極收集之前必須移動的距離較長，因此容易 因再結合而消失之故。 於此相對，本實施形態中，n側電極lln被分割為複 數個梳齒狀電極部14。而且，p侧的指狀電極部12pl係位 於匯流條部13η之間。因此，n側的匯流條部13n的面積 較小。此外，在位於太陽能電池基板1〇的匯流條部13n 之下的部分所産生的作為少數載子的電洞在被p侧電極 lip收集之前必須移動的距離較短。因此，本實施形態能 夠有效地抑制電洞因再結合而消失。從而能夠改善光電變 換效率。 此外，本實施形態中，與指狀電極部12pl同樣，指 狀電極部12p2也設置為與匯流條部1311在y方向相對向。 從而能夠有效地抑制電洞因再結合而消失。從而能夠進一 步實現經改善的光電變換效率。 從進一步改善光電變換效率的觀點來看，較佳為使匯 流條部13η的面積減小。因此較佳為使匯流條部l3n間的 最短距離增1具體而言，匯流條部13n之間的最短距離 較佳為0.001mm以上。但是，如果使匯流條部l3n之間的 最短距離過長，料有因電喊分的增加等反而使光電變 換效率降低的情況。因此匯流條部.之間的最短距離較 佳為10mm以下，更佳為4mm以下。 以下，說明實施本發明的較佳形態的另一例。以下的 說明中，對於與上述第—實施形態具有實質上共通的功能 的構件標注共通的符號，並省略其說明。 323796 201242053 (第二實施形態） 第2圖是第二實施形態的太陽能電池的概要平面圖。 '本實施形態的太陽能電池2中之匯流條部13η的形狀 及指狀電極部12pl的形狀係與上述第一實施形態的太陽 能電池1不同。太陽能電池2中，匯流條部13η之寬度係 從X方向的χ2側朝xl侧變窄。具體而言，匯流條部ι3η 係上底朝向χ2側的梯形形狀。指狀電極部12ρ1的前端部 之寬度係從X方向的χ2侧朝χΐ侧變寬。具體而言，指狀 電極部12pl的前端部係下底朝向χΐ侧的梯形形狀。 因此，與上述第一實施形態的太陽能電池丨相比，太 陽能電池2係使匯流條部13η的面積減小。此外，指狀電 極部12pl之寬度係往χΐ側變寬，因此在位於太陽能電池 座板10的匯流條部13η之下的部分所産生的電洞在被p 侧電極lip收集之前必須移動的距離會變得更短。因此能 夠有效地抑制電洞因再結合而消失。從而能夠獲得進一步 改善後的光電變換效率。 另外，匯流條部13η的底角（及指狀電極部i2pi的前 端部的底角）較佳為〇。至9〇。（180。至9〇。），更佳為3〇。至 丨沁。（150。至 120。）。 k第三實施形態） 第3圖係第三實施形態的太陽能電池的概要平面圖。 如第3圖所示’本實施形態的太陽能電池3中，在y方向 相鄰的梳齒狀電極部14之間配置有複數個指狀電極部 2pl，這一點與上述第一實施形態的太陽能電池1不同。 323796 12 201242053 在該情況下’也能夠與上述第一實施形態同樣地實現經改 善的光電變換效率。 (第四實施形態） 第4圖係第四實施形態的太陽能電池的概要平面圖。 如第4圖所示，與上述第二實施形態同樣地，本實施形態 的太陽能電池4係將匯流條部i3n及指狀電極部I2pl的前 端部各自形成為梯形形狀，這一點與上述第三實施形態的 太陽能電池3不同。因此，本實施形態的太陽能電池4具 有比太陽能電池3更高的光電變換效率。 (第五實施形態） 第5圖係第五實施形態的太陽能電池的概要平面圖。 第6圖是將第五實施形態的太陽能電池的一部分放大後的 概要平面圖。如第5圖所示，本實施形態的太陽能電池5 卜P側電極Πρ具有電極部15p，這一點與第一實施形態 的太陽能電池1不同。 ^電極部15p係與指狀電極部12pl電性連接。具體而 °本實施形態中，電極部15p係連接複數個指狀電極部 12ρι的前端部。電極部15p設置為在匯流條部13n的χΐ 側’沿著y方向延伸。 例如，第一實施形態的太陽能電池1中，如第7圖所 =’太陽能電池基板10中在位於匯流條部13㈣χΐ側部 二之:的部分所産生的電洞16，係在被指狀電極部]2p收 消^前必須移動較長的距離。從而電洞16容易因再結合而 323796 13 201242053 因此= 態十’設置有上述的電極部咖。 ’ 7 6圖㈣，太陽能電池基板1()中在位於匯流條 =13 η的X1側部分之下的部分所產生的電洞！ 6在被p側 電極Up的電極部15p收集之前必須移動的距離較短。因 此電洞16難以因再結合而消失。從而能夠實現經進一步改 善的光電變換效率。 ，另外，在上述實施形態中，係以一導電型為_、以 另-導電型為p型的情況為例進行說明。但是本發明並不 限定於此，也可以採用將以一導電型為卩型、以另一導電 型為η型的極性替換後的構成❶在該情況下，電子成為少 數載子，而能夠得到與電洞為少數載子時同樣的作用效果。 【圖式簡單說明】 第1圖係第一實施形態的太陽能電池的概要平面圖。 第2圖係第二實施形態的太陽能電池的概要平面圖。 第3圖係第三實施形態的太陽能電池的概要平面圖。 第4圖係第四實施形態的太陽能電池的概要平面圖。 第5圖係第五實施形態的太陽能電池的概要平面圖。 第6圖係將第五實施形態的太陽能電池的一部分放大 後的概要平面圖。 第7圖係將第一實施形態的太陽能電池的一部分放大 後的概要平面圖。 【主要元件符號說明】 I至5 太陽能電池 1〇 太陽能電池基板 10a 背面 10an η型表面 323796 14 201242053 l()ap p型表面 lln η側電極 Up p側電極 12η、 12ρ、12ρ1 指狀電極部 13n ' 13p 匯流條部 14 梳齒狀電極部 15p 電極部 16 電洞 323796 15^ ^^^1; ;2" and: the P pole portion 12p2 located at the outermost side in the y direction among the plurality of finger electrode portions 12n. The finger portion 12p2 is opposed to the > portion of the bus bar portion in the y direction. That is, the front end x direction of the finger electrode portion reaches the position of the bus bar portion 13n. In the present embodiment, the front end on the x1 side of the finger electrode portion 12p2 is flush with the end side on the x1 side of the bus bar portion 13n. However, the present invention is not limited to this configuration. The χ1 side front end of the finger f pole portion 12p2 can be located in the quotation "it strip. The xi side of the 卩13η is located closer to the χ2 side, and may be located closer to the χ1 side than the leading end of the bus bar portion 13n on the x1 side. However, as described in the above Patent Document 1, when each of the n-side electrode and the p-side electrode is constituted by one comb-shaped electrode, it is difficult to sufficiently improve the photovoltaic efficiency. This may be because the electricity 323796 201242053 hole which is generated as a minority carrier in the portion below the bus bar portion of the n-side electrode of the solar cell substrate has to be moved a long distance before being collected by the P-side electrode, so that it is easy It disappeared because of recombination. On the other hand, in the present embodiment, the n-side electrode 11n is divided into a plurality of comb-shaped electrode portions 14. Further, the finger electrode portion 12pl on the p side is located between the bus bar portions 13n. Therefore, the area of the bus bar portion 13n on the n side is small. Further, the hole which is a minority carrier generated at a portion below the bus bar portion 13n of the solar cell substrate 1 is required to move a short distance before being collected by the p-side electrode lip. Therefore, this embodiment can effectively suppress the disappearance of the hole due to recombination. Thereby, the photoelectric conversion efficiency can be improved. Further, in the present embodiment, similarly to the finger electrode portion 12p1, the finger electrode portion 12p2 is also provided to face the bus bar portion 1311 in the y direction. Thereby, it is possible to effectively suppress the disappearance of the hole due to recombination. Thereby, the improved photoelectric conversion efficiency can be further realized. From the viewpoint of further improving the photoelectric conversion efficiency, it is preferable to reduce the area of the bus bar portion 13n. Therefore, it is preferable to increase the shortest distance between the bus bar portions 13n by one. Specifically, the shortest distance between the bus bar portions 13n is preferably 0.001 mm or more. However, if the shortest distance between the bus bar portions 13n is too long, the photoelectric conversion efficiency may be lowered due to an increase in the number of electric shunts. Therefore, the shortest distance between the bus bar portions is preferably 10 mm or less, more preferably 4 mm or less. Hereinafter, another example of a preferred embodiment of the present invention will be described. In the following description, members having substantially the same functions as those of the above-described first embodiment are denoted by the same reference numerals, and their description will be omitted. 323796 201242053 (Second embodiment) Fig. 2 is a schematic plan view of a solar cell according to a second embodiment. The shape of the bus bar portion 13n and the shape of the finger electrode portion 12pl in the solar battery 2 of the present embodiment are different from those of the solar battery 1 of the first embodiment described above. In the solar battery 2, the width of the bus bar portion 13n is narrowed from the χ2 side in the X direction toward the x1 side. Specifically, the bus bar portion ι3η is formed in a trapezoidal shape in which the bottom portion faces the χ2 side. The width of the tip end portion of the finger electrode portion 12p1 is widened from the χ2 side in the X direction toward the χΐ side. Specifically, the front end portion of the finger electrode portion 12pl has a trapezoidal shape in which the lower bottom faces the crotch side. Therefore, compared with the solar cell cartridge of the first embodiment described above, the solar cell 2 reduces the area of the bus bar portion 13n. Further, the width of the finger electrode portion 12pl is widened toward the χΐ side, and therefore the distance that the hole generated in the portion below the bus bar portion 13n of the solar cell seat panel 10 must move before being collected by the p-side electrode lip Will become shorter. Therefore, it is possible to effectively suppress the hole from disappearing due to recombination. Thereby, the photoelectric conversion efficiency after further improvement can be obtained. Further, the bottom corner of the bus bar portion 13n (and the bottom corner of the front end portion of the finger electrode portion i2pi) is preferably 〇. To 9 〇. (180. to 9〇.), more preferably 3〇. To 丨沁. (150. to 120.). k Third Embodiment) Fig. 3 is a schematic plan view showing a solar cell according to a third embodiment. As shown in Fig. 3, in the solar cell 3 of the present embodiment, a plurality of finger electrode portions 2pl are disposed between the adjacent comb-shaped electrode portions 14 in the y direction, and the solar energy of the first embodiment described above is used. Battery 1 is different. 323796 12 201242053 In this case as well, the improved photoelectric conversion efficiency can be realized in the same manner as in the first embodiment described above. (Fourth embodiment) Fig. 4 is a schematic plan view showing a solar cell according to a fourth embodiment. As shown in Fig. 4, in the solar battery 4 of the present embodiment, the front end portions of the bus bar portion i3n and the finger electrode portion I2pl are formed in a trapezoidal shape, as in the second embodiment. The solar cell 3 of the embodiment is different. Therefore, the solar cell 4 of the present embodiment has higher photoelectric conversion efficiency than the solar cell 3. (Fifth Embodiment) Fig. 5 is a schematic plan view showing a solar cell according to a fifth embodiment. Fig. 6 is a schematic plan view showing a part of the solar cell of the fifth embodiment in an enlarged manner. As shown in Fig. 5, the solar cell 5 of the present embodiment is different from the solar cell 1 of the first embodiment in that the P-side electrode Πρ has the electrode portion 15p. The electrode portion 15p is electrically connected to the finger electrode portion 12pl. Specifically, in the present embodiment, the electrode portion 15p is connected to the distal end portions of the plurality of finger electrode portions 12ρι. The electrode portion 15p is provided to extend in the y direction on the 侧 side of the bus bar portion 13n. For example, in the solar battery 1 of the first embodiment, as shown in Fig. 7, the hole 16 generated in the portion of the solar cell substrate 10 at the side of the side of the bus bar portion 13 (four) is attached to the finger electrode. Department] 2p must move a long distance before it is removed. Therefore, the hole 16 is easily recombined. 323796 13 201242053 Therefore, the state of the electrode is set. In the solar cell substrate 1 (), the hole generated in the portion below the X1 side portion of the bus bar = 13 η! 6 The distance that must be moved before being collected by the electrode portion 15p of the p-side electrode Up is short. Therefore, the hole 16 is difficult to disappear due to recombination. Thereby, the photoelectric conversion efficiency which is further improved can be realized. Further, in the above embodiment, a case where one conductivity type is _ and the other conductivity type is p type will be described as an example. However, the present invention is not limited thereto, and a configuration in which one conductivity type is a 卩 type and another conductivity type is an η type polarity may be used. In this case, electrons become a minority carrier, and thus an electron can be obtained. The same effect as when the hole is a minority carrier. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a schematic plan view showing a solar cell according to a first embodiment. Fig. 2 is a schematic plan view showing a solar cell according to a second embodiment. Fig. 3 is a schematic plan view showing a solar cell according to a third embodiment. Fig. 4 is a schematic plan view showing a solar cell of a fourth embodiment. Fig. 5 is a schematic plan view showing a solar cell of a fifth embodiment. Fig. 6 is a schematic plan view showing an enlarged portion of a solar cell according to a fifth embodiment. Fig. 7 is a schematic plan view showing an enlarged portion of the solar cell of the first embodiment. [Description of main components] I to 5 Solar cell 1〇 Solar cell substrate 10a Back surface 10an η-type surface 323796 14 201242053 l()ap p-type surface 11n η side electrode Up p side electrode 12n, 12ρ, 12ρ1 Finger electrode portion 13n ' 13p bus bar portion 14 comb-shaped electrode portion 15p electrode portion 16 hole 323796 15