201240936 六、發明說明： 【發明所屬之技術領域】 本發明係關於一種導電性糊及太陽能電池，更詳細而古 係關於一種適合於太陽能電池之電極形成之導電性糊、及 使用該導電性糊而製造之太陽能電池。 【先前技術】 太陽能電池通常係於半導體基板之一主面形成有特定圖 案之受光面電極。又，於除上述受光面電極以外之半導體 基板上形成有抗反射膜，以上述抗反射膜抑制所入射之太 陽光之反射損失，藉此提昇太陽光向電能之轉換效率。 上述受光面電極通常係使用導電性糊以如下方式形成。 即，導電性糊含有導電性粉末、玻璃料及有機媒劑，將導 電性糊塗佈於形成於半導體基板上之抗反射膜之表面’形 成特定圖案之導電膜。繼而，於煅燒過程中使玻璃料熔 融，將導電膜下層之抗反射膜分解、去除，藉此燒結導電 膜而形成受光面電極’並且將該受光面電極與半導體基板 接著，使兩者導通。 如上述般於煅燒過程中分解、去除抗反射膜，並將半導 體基板與受光面電極接著之方法被稱為燒透（Fire Through)，太陽能電池之轉換效率較大地依存於燒透性。 即，已知若燒透性不充分，則轉換效率下降，作為太陽能 電池之基本性能較差。 又，一般認為於此種太陽能電池中，為提高受光面電極 與半導體基板之接著強度，較佳為使用低軟化點之玻璃 161504.doc 201240936 料。 作為低軟化點之玻璃料’自先前以來使用有鉛系之玻璃 料’但由於Pb之環境負荷較大’故而希望出現代替鉛系玻 璃料之新的材料。 就此種觀點而言，於專利文獻1中提出有一種導電性 糊’其玻璃料之軟化點為570〜76CTC，且該玻璃料係以按 莫耳比計B2〇3/Si〇2成為0.3以下之比例之方式含有b2〇3及 Sl〇2，並含有未達20 mol%之Bi203。 於專利文獻1中，雖為不含鉛之非鉛系導電性糊，但即 便於相對低溫下進行煅燒，亦可獲得受光面電極與半導體 基板之接著強度較大，且受光面電極與半導體基板之間之 接觸電阻較小的太陽能電池。 [先前技術文獻] [專利文獻] [專利文獻1]國際公開2007/102287號（技術方案2，段落 編號[0016]) 【發明内容】 [發明所欲解決之問題] 於如專利文獻1之先前之太陽能電池中，如上所述般將 導電性糊塗佈於半導體基板上之抗反射膜上，並將其作為 被煅燒物加以煅燒而製造。 然而，由於上述被煅燒物係以高速通過煅燒爐，故而有 因於煅燒過程中未充分地進行燒透，而抗反射膜殘留於受 光面電極與半導體基板之間之虞。其結果，有因產生受光 161504.doc 201240936 面電極未與半導體基板接著之部分，而導致轉換效率下降 之虞。 又’在太陽能電池之量產過程，’由於大量之被烺燒物 以高速通過炮燒爐，故而即便將锻燒爐設定成特定溫度， 亦有受通過煅燒爐内之被煅燒物之搬送狀態的影響，煅燒 溫度易於產生變動，而自煅燒爐中排出燒透不充分之製品 之虞。 因此’為使用導電性糊穩定地生產太陽能電池’需要嚴 格管理般燒條件。尤其於如專利文獻i般使用軟化點較高 為570〜760t之玻璃料之情形時，雖可於最適合之般燒條 件下獲得高轉換效率，但容易受锻燒溫度變動之影響，而 難以穩定地獲得較高之轉換效率。 又，於專利文獻1中，由於僅使用有軟化點較高之〗種玻 璃料，故而於導電性糊中所含之黏合劑樹脂等熱分解或燃 燒而消失後至玻璃成分軟化為止之期間，應成為受光面電 極之導電膜與半導體基板之間的接著持續極弱之狀態。於 此種狀態下導電性粉末之燒結過度地進行之情形時，於煅 燒前較多地存在之導電性粉末與半導體基板之接觸部位便 減少，因此難以獲得所需之較高之轉換效率。 本發明係鑒於上述情況而完成者，其目的在於提供.一種 雖為非鉛系但即便於較寬之溫度區域内進行煅燒，亦可穩 定地獲得較高之轉換效率之太陽能電池的電極形成用導電 性糊及使用該導電性糊而製造之太陽能電池。 [解決問題之技術手段] 161504.doc 201240936 本發明者為達成上述目的達成而進行努力研究，結果獲 得如下見解：藉由使用ΙΑ相對於si〇2之莫耳比率被調整 成0.4以下且軟化點相差20〇c以上之2種非鉛系破璃料且 若將兩者之玻璃料之調配比率設為1/4〜4/1的範圍，則即便 於煅燒中產生溫度變動亦可確保良好之燒透性，藉此可於 較寬之煅燒溫度區域内穩定地獲得具有所需之較高轉換效 率之太陽能電池。 本發明係基於此種見解而完成者，本發明之導電性糊之 特徵在於：其係用以形成太陽能電池之電極者；其含有導 電性粉末、第1玻璃料、軟化點較該第i玻璃料高2〇它以上 之第2玻璃料及有機媒劑；上述第丨及第2玻璃料不含扑並 至少含有B及Si，且B相對於Si之莫耳比率分別換算成§丨〇2 及B2〇3而為0.4以下；上述第1玻璃料與上述第2玻璃料之 含有比率以重量比計為1/4〜4/1。 又，本發明之導電性糊較佳為上述第丨玻璃料之軟化點 為510〜570°C，上述第2玻璃料之軟化點為53〇〜68〇<t。 進而，本發明之導電性糊較佳為上述第丨玻璃料含有 20〜40莫耳％之範圍之則2〇3、5〜2〇莫耳％之範圍之以〇、及 5莫耳％以下之範圍之A1203。 又，本發明之導電性糊較佳為上述第2玻璃料含有5〜3〇 莫耳％之範圍之BiW3、5〜25莫耳。/。之範圍iBa〇、及5莫耳 %以下之範圍之Al2〇3。 又，本發明之導電性糊較佳為上述第丨及第2玻璃料含有 Bi及Ba中之至少任一者。 161504.doc 201240936 進而，本發明之導電性糊較佳為含有Zn〇。 又，本發明之導電性糊較佳為上述導電性粉末為八§粉 末。 又，本發明之太陽能電池之特徵在於··於半導體基板之 一主面形成有抗反射膜及貫通該抗反射膜之受光面電極； 上述電極係將上述任一導電性糊燒結而成。 [發明之效果] 根據本發明之導電性糊，由於含有八§粉末等導電性粉 末、軟化點例如為510〜570t之第夏玻璃料、軟化點例如為 530〜680t且具有較上述第丨玻璃料高2〇t以上之軟化點之 第2玻璃料及有機媒劑，上述第丨及第2玻璃料不含抑並至 少3有B及Si，且B相對於Si之莫耳比率分別換算成8丨〇2及 Bz〇3而為0.4以下，上述第丨玻璃料與上述第2玻璃料之含 有比率以重量比計為1/4〜4/卜故而一方面可藉由軟化點相 對較低之第1玻璃料確保接著性，另一方面可藉由軟化點 較第^玻璃料高抓以上之第2玻璃料抑制受光面電極與半 導體基板之間之過度的玻璃流動’藉此即便於較寬之溫度 品或内進行浴燒’亦可喊保良好之燒透性而穩定地獲得具 有較高之轉換效率之太陽能電池。 又，上述第1玻璃料含有20〜4〇莫耳％之範圍之Bi2〇3、 5〜20莫耳％之範圍之祕、及5莫耳％以下之範圍之八阶， 上述第2玻璃料含有5〜3〇莫耳％之範圍之Bi2〇3、>25莫耳 。之範圍之BaO、及5莫耳％以下之範圍之Al2〇3，藉此可獲 得燒透性及化學耐久性良好之導電性糊。 I61504.doc 201240936 又，藉由含有ZnO，可進一步促進燒透性，可實現電極 與半導體基板之間之接觸電阻較低之太陽能電池。 又’根據本發明之太陽能電池，由於在半導體基板之一 主面形成有抗反射膜及貫通該抗反射膜之電極，且上述電 極係將上述任一導電性糊燒結而成，故而即便於較寬之溫 度區域内進行锻燒’亦可穩定地獲得具有較高之轉換效率 之太陽能電池。 【實施方式】 其次’詳細地說明本發明之實施形態。 圖1係表示使用本發明之導電性糊而製造之太陽能電池 之一實施形態的主要部分剖面圖。 該太陽能電池中，於以Si為主成分之半導體基板丨之一 主面形成有抗反射膜2及受光面電極3，且於該半導體基板 1之另一主面形成有背面電極4。 半導體基板1具有p型半導體層1!3與11型半導體層la，且 於P型半導體層lb之上表面形成有η型半導體層la。該半導 體基板1例如可藉由使雜質擴散至單晶或多晶之p型半導體 層lb之一主面形成較薄之η型半導體層la而獲得，但 只要為於p型半導體層ib之上表面形成有n型半導體層la 者，則其構造及製造方法並無特別限定。又，半導體基板 1亦可使用於η型半導體層^之一主面形成有較薄之p型半 導體層lb之構造者、或於半導體基板丨之一主面之一部分 形成有p型半導體層11?與n型半導體層la之兩者之構造者。 總之，只要為形成有抗反射膜2之半導體基板1之主面，則 161504.doc 201240936 可有效地使用本發明之導電性糊。再者，於圖1中，半導 體基板1之表面被記載為平面狀，但為有效地將太陽光封 閉於半導體基板1中，表面以具有微小凹凸構造之方式形 成0 抗反射膜2係由氮化矽（SiNx)等絕緣性材料形成，抑制箭 頭A所示之向太陽光之受光面之光的反射，迅速且效率良 好地將太陽光導入至半導體基板4。作為構成該抗反射 膜2之材料，並不限定於上述氮化矽，可使用其他絕緣性 材料’例如氧化石夕或氧化鈦，，亦可併用2種以上之絕緣性 材料。又’只要為結晶Si系’則可使用單晶si及多晶以之 任—者。 受光面電極3係於半導體基板旧通抗反射膜2而形 成。該受光面電極3係藉由使用絲網印刷等將後述之本發 明之導電性糊塗佈於半導體基板，製作導電膜並進行 煅燒而形成。即，於形成受光面電極3之锻燒過程中，導 電膜下層之抗反射膜2被分解、去除而燒透，藉此以貫通 抗：射膜2之形態於半導體基板1上形成受光面電極3。 ^面電極3具體而言係如圖2所示般呈梳齒狀地並排設 置有…狀電極…、..·5η，與指狀電極5a、 讣’.·5η呈父又狀地設置有母線電極6，且指狀電極5a' 面電極Γ之與Λ線電極6電性連接。並且，於除設置有受光 此，夢由广以外之剩餘區域中形成有抗反射膜2。如 電，=電極Μ對半導體基板卜產生之電力進行集 门夺错由母線電極6提取至外部。 J6I504.doc 201240936 者面電極4具體而言係如圖3所示般包括形成於p型半導 體層lb之背面之包含八丨等之集電電極7、及形成於該集電 電極7之背面且與該集電電極7電性連接之包含Ag等之提取 電極8並且，半導體基板1中產生之電力由集電電極7進 行集電’並藉由提取電極8提取電力。 其次’對用以形成受光面電極3之本發明之導電性糊進 行詳細闡述。 本發明之導電性糊含有導電性粉末、軟化點不同之2種 非錯系玻璃料（第1及第2玻璃料）及有機媒劑。 並且’第1及第2玻璃料均至少含有b及si，且滿足下述 算式（1)〜(3)。201240936 VI. Description of the Invention: [Technical Field] The present invention relates to a conductive paste and a solar cell, and more particularly to a conductive paste suitable for electrode formation of a solar cell, and the use of the conductive paste And the manufacture of solar cells. [Prior Art] A solar cell is usually a light-receiving surface electrode in which a specific pattern is formed on one main surface of a semiconductor substrate. Further, an anti-reflection film is formed on the semiconductor substrate other than the light-receiving surface electrode, and the reflection loss of the incident sunlight is suppressed by the anti-reflection film, thereby improving the conversion efficiency of sunlight to electric energy. The above-mentioned light-receiving surface electrode is usually formed in the following manner using a conductive paste. In other words, the conductive paste contains a conductive powder, a glass frit, and an organic vehicle, and a conductive paste is applied to the surface of the antireflection film formed on the semiconductor substrate to form a conductive film having a specific pattern. Then, the glass frit is melted during the calcination, and the antireflection film under the conductive film is decomposed and removed, whereby the conductive film is sintered to form the light-receiving surface electrode ', and the light-receiving surface electrode and the semiconductor substrate are next, and the two are electrically connected. As described above, the method of decomposing and removing the antireflection film during the calcination, and connecting the semiconductor substrate and the light receiving surface electrode is referred to as "fire through", and the conversion efficiency of the solar cell is largely dependent on the burnt property. That is, it is known that if the fire-through property is insufficient, the conversion efficiency is lowered, and the basic performance as a solar battery is inferior. Further, in such a solar cell, in order to improve the adhesion strength between the light-receiving surface electrode and the semiconductor substrate, it is preferable to use a glass having a low softening point 161504.doc 201240936. As a glass frit having a low softening point, a lead-based glass frit has been used since, but since the environmental load of Pb is large, a new material for replacing the lead-based glass frit is desired. From this point of view, Patent Document 1 proposes a conductive paste having a glass material having a softening point of 570 to 76 CTC, and the glass frit having a molar ratio of B2〇3/Si〇2 of 0.3 or less. The ratio includes b2〇3 and S1〇2, and contains less than 20 mol% of Bi203. In Patent Document 1, although the lead-free conductive paste is not contained, even if it is fired at a relatively low temperature, the bonding strength between the light-receiving surface electrode and the semiconductor substrate can be obtained, and the light-receiving surface electrode and the semiconductor substrate can be obtained. A solar cell with a small contact resistance. [Prior Art Document] [Patent Document 1] [Patent Document 1] International Publication No. 2007/102287 (Technical Solution 2, Paragraph No. [0016]) [Disclosure] [Problems to be Solved by the Invention] As in Patent Document 1 In the solar cell, the conductive paste is applied onto the antireflection film on the semiconductor substrate as described above, and is produced by firing the material as a burned material. However, since the above-mentioned calcined material passes through the calcining furnace at a high speed, the anti-reflection film remains in the crucible between the light-receiving surface electrode and the semiconductor substrate because the anti-reflection film is not sufficiently burned during the firing. As a result, there is a possibility that the conversion efficiency is lowered due to the fact that the surface electrode is not incident on the semiconductor substrate by the light receiving element 161504.doc 201240936. In addition, in the mass production process of solar cells, 'a large number of burnt materials pass through the gun furnace at a high speed, so even if the calciner is set to a specific temperature, there is a state of being transported by the calcined material in the calciner. As a result, the calcination temperature is liable to change, and the crucible is discharged from the calciner. Therefore, it is necessary to strictly manage the burning conditions for the stable production of solar cells using conductive paste. In particular, when a glass frit having a softening point of 570 to 760 t is used as in the case of the patent document i, although high conversion efficiency can be obtained under the most suitable firing conditions, it is easily affected by the variation of the calcination temperature, and it is difficult. Stablely achieve higher conversion efficiency. Further, in Patent Document 1, since only a glass frit having a high softening point is used, the binder resin contained in the conductive paste is thermally decomposed or burned and disappears until the glass component is softened. It should be a state in which the conductive film of the light-receiving electrode and the semiconductor substrate continue to be extremely weak. When the sintering of the conductive powder is excessively performed in such a state, the contact portion of the conductive powder which is present in a large amount before the calcination and the semiconductor substrate is reduced, so that it is difficult to obtain a desired high conversion efficiency. The present invention has been made in view of the above circumstances, and an object of the invention is to provide an electrode for solar cell which can stably obtain a high conversion efficiency even if it is non-lead-based, but can be calcined in a wide temperature range. A conductive paste and a solar cell produced using the conductive paste. [Technical means for solving the problem] 161504.doc 201240936 The inventors of the present invention conducted an effort to achieve the above object, and as a result, obtained the following findings: by using the molar ratio of ΙΑ to si〇2 to 0.4 or less and softening point When two kinds of non-lead-based glass frits having a difference of 20 〇c or more and the ratio of the glass frit of the two are set to the range of 1/4 to 4/1, even if temperature fluctuation occurs during firing, it is ensured that the temperature is good. The burn-through property can thereby stably obtain a solar cell having a desired high conversion efficiency in a wide calcination temperature region. The present invention is based on the knowledge that the conductive paste of the present invention is characterized in that it is used to form an electrode of a solar cell; it contains a conductive powder, a first glass frit, and a softening point compared to the ith glass. a second glass frit and an organic medium having a material height of 2 Å or more; the first and second glass frits are not contained and contain at least B and Si, and the molar ratio of B to Si is converted into § 丨〇 2 and B2〇3 is 0.4 or less; the content ratio of the said first glass frit and said said said glass frit is 1/4~4/1 by weight ratio. Further, in the conductive paste of the present invention, it is preferable that the softening point of the second glass frit is 510 to 570 ° C, and the softening point of the second glass frit is 53 〇 to 68 〇 < t. Further, the conductive paste of the present invention preferably has a range of 2 〇 3, 5 〜 2 〇 mol %, and 5 摩尔% or less in the range of 20 to 40 mol% of the second glass frit. The range of A1203. Further, in the conductive paste of the present invention, it is preferable that the second glass frit contains BiW3 and 5 to 25 moles in a range of 5 to 3 % by mole. /. The range is iBa〇, and Al2〇3 in the range of 5 mol% or less. Further, in the conductive paste of the present invention, it is preferable that at least one of Bi and Ba is contained in the second and second glass frits. Further, the conductive paste of the present invention preferably contains Zn ruthenium. Further, in the conductive paste of the present invention, it is preferable that the conductive powder is an octa-powder powder. Further, the solar cell of the present invention is characterized in that an antireflection film and a light receiving surface electrode penetrating the antireflection film are formed on one main surface of the semiconductor substrate, and the electrode is formed by sintering any of the above conductive pastes. [Effects of the Invention] The conductive paste of the present invention contains a conductive powder such as octa powder, a summer glass frit having a softening point of, for example, 510 to 570 t, and a softening point of, for example, 530 to 680 t and having the above-mentioned third glass. The second glass frit and the organic vehicle having a softening point of 2 〇t or more, the second and second glass frits are not inhibited and at least 3 have B and Si, and the molar ratio of B to Si is converted into 8丨〇2 and Bz〇3 are 0.4 or less, and the content ratio of the second glass frit to the second glass frit is 1/4 to 4/by weight, and the softening point is relatively low on the one hand. The first glass frit ensures adhesion, and on the other hand, the second glass frit which is higher than the first glass frit by the softening point can suppress excessive glass flow between the light-receiving surface electrode and the semiconductor substrate, thereby making it wider. The temperature product or the inside of the bath can also be used to secure a good burn-through property and stably obtain a solar cell having a high conversion efficiency. Further, the first glass frit contains Bi2〇3, a range of 5 to 20 mol% in a range of 20 to 4 mol%, and an eighth order in a range of 5 mol% or less, and the second frit. Bi2〇3, >25 mol containing a range of 5 to 3 mol%. In the range of BaO and Al2〇3 in the range of 5 mol% or less, a conductive paste having excellent fire-through property and chemical durability can be obtained. I61504.doc 201240936 Further, by containing ZnO, the fire-through property can be further promoted, and a solar cell having a low contact resistance between the electrode and the semiconductor substrate can be realized. Further, in the solar cell according to the present invention, since the antireflection film and the electrode penetrating the antireflection film are formed on one main surface of the semiconductor substrate, and the electrode is sintered by any of the above conductive pastes, even if It is also possible to stably obtain a solar cell having a high conversion efficiency by performing calcination in a wide temperature region. [Embodiment] Next, an embodiment of the present invention will be described in detail. Fig. 1 is a cross-sectional view showing the principal part of an embodiment of a solar cell produced by using the conductive paste of the present invention. In the solar cell, the anti-reflection film 2 and the light-receiving surface electrode 3 are formed on one main surface of a semiconductor substrate having Si as a main component, and the back surface electrode 4 is formed on the other main surface of the semiconductor substrate 1. The semiconductor substrate 1 has a p-type semiconductor layer 1!3 and an 11-type semiconductor layer 1a, and an n-type semiconductor layer 1a is formed on the upper surface of the P-type semiconductor layer 1b. The semiconductor substrate 1 can be obtained, for example, by diffusing impurities to one of the main surfaces of the single crystal or polycrystalline p-type semiconductor layer 1b to form a thin n-type semiconductor layer 1a, but as long as it is above the p-type semiconductor layer ib The structure and manufacturing method of the n-type semiconductor layer la are not particularly limited. Further, the semiconductor substrate 1 may be used in a structure in which a thin p-type semiconductor layer 1b is formed on one main surface of the n-type semiconductor layer, or a p-type semiconductor layer 11 is formed in a part of one main surface of the semiconductor substrate. The constructor of both the n-type semiconductor layer la and the n-type semiconductor layer la. In short, as long as it is the main surface of the semiconductor substrate 1 on which the anti-reflection film 2 is formed, the conductive paste of the present invention can be effectively used in 161504.doc 201240936. In FIG. 1, the surface of the semiconductor substrate 1 is described as being planar, but the solar light is effectively sealed in the semiconductor substrate 1, and the surface is formed to have a fine uneven structure. The anti-reflection film 2 is made of nitrogen. The insulating material such as bismuth (SiNx) is formed, and the reflection of the light toward the light receiving surface of the sunlight indicated by the arrow A is suppressed, and the sunlight is introduced into the semiconductor substrate 4 quickly and efficiently. The material constituting the antireflection film 2 is not limited to the above-described tantalum nitride, and other insulating materials such as oxidized oxide or titanium oxide may be used, or two or more kinds of insulating materials may be used in combination. Further, any single crystal Si or polycrystal may be used as long as it is a crystalline Si system. The light-receiving surface electrode 3 is formed by laminating the anti-reflection film 2 of the semiconductor substrate. The light-receiving surface electrode 3 is formed by applying a conductive paste of the present invention described later to a semiconductor substrate by screen printing or the like to form a conductive film and firing it. In other words, in the calcination process in which the light-receiving surface electrode 3 is formed, the anti-reflection film 2 under the conductive film is decomposed, removed, and burned, whereby the light-receiving surface electrode is formed on the semiconductor substrate 1 in the form of the anti-reflection film 2 3. Specifically, the surface electrode 3 is provided in a comb-like manner as shown in FIG. 2, and is provided with ... electrodes, ..., 5n, and is provided in a parent shape with the finger electrodes 5a and 讣'.·5n. The bus bar electrode 6 is electrically connected to the Λ wire electrode 6 of the finger electrode 5a'. Further, in addition to the light receiving, the anti-reflection film 2 is formed in the remaining area other than the dream. For example, the electric current, the electrode Μ, and the electric power generated by the semiconductor substrate are subjected to the assembly error extraction by the bus electrode 6 to the outside. J6I504.doc 201240936 The surface electrode 4 includes, as shown in FIG. 3, a collector electrode 7 including an erbium or the like formed on the back surface of the p-type semiconductor layer 1b, and a back surface of the collector electrode 7 and The extraction electrode 8 including Ag or the like is electrically connected to the collector electrode 7, and the electric power generated in the semiconductor substrate 1 is collected by the collector electrode 7', and electric power is extracted by the extraction electrode 8. Next, the conductive paste of the present invention for forming the light-receiving surface electrode 3 will be described in detail. The conductive paste of the present invention contains two kinds of non-missable glass frits (first and second glass frits) having different softening points and an organic medium. Further, both the first and second glass frits contain at least b and si, and satisfy the following formulas (1) to (3).
Ts2 — Tsi ^ 20 ... (1) α/β$0.4 ... (2) l/4^x/y ^4/1 …（3) 此處，Ts,為第1玻璃料之軟化點，Ts2為第2玻璃料之軟 化點，α為各玻璃料中之ΙΑ之含有莫耳量，p為各玻璃料 中之Si〇2之含有莫耳量’ x為第1玻璃料之含有重量，^為 第2玻璃料之含有重量。 即，本發明之導電性糊包含至少含有B及Si且軟化點不 同之2種非鉛系玻璃料’第2玻璃料之軟化點Ts2較第1玻璃 料之軟化點Tsi尚20 C以上，Βζ〇3相對於Si〇2之莫耳比率 α/β設為0.4以下，且第1玻璃料與第2玻璃料之重量比率x/y 設為1 /4〜4/1。藉此，即便於較寬之溫度區域内進行煅燒， 亦可確保良好之燒透性，而可穩定地獲得具有較高之轉換 161504.doc -10 201240936 效率之太陽能電池。 以下’對使玻璃料滿足上述算式（1)〜(3)之理由進行闡 述。 (1)第1及第2玻璃料之軟化點丁3丨、 由於 3 有 Sl〇2、B2〇3、Bi2〇3、83〇之 si B Bi Ba 系之玻 璃料具有良好之燒透性，故而有望作為錯系玻璃料之代替 物質。 並且，由於Si-B-Bi-Ba系玻璃料中軟化點較低之玻璃料 在:¾•燒過私中谷易於党光面電極3與半導體基板^ (η型半導 體層la)之界面處流動，而促進抗反射膜之分解、去除， 故而可有助於燒透性之提昇。又，亦可提昇受光面電極3 與半導體基板1之接著強度。 然而另方面有低軟化點之非鉛系玻璃料於應成為受 光面電極3之導電膜與半導體基板以界面處過度地流動， 向半導體基板1側擴散而腐钮該半導體基板t之虞。其結 果’有形成於η型半導體層型半導體層化之間之叩接 面被破壞’而無法獲得所需之較高轉換效率之虞。又，於 Λ It形時#導電性粉末經由玻璃料向半導體基板1側過 度地擴散，則並聯電阻下降，其結果，開放輸出端子時之 電壓、即開路電壓V〇C下降’結果無法獲得較高之轉換效 率。 /此’於本實施形態中，藉由使導電性糊中含有軟化點 較低之第1玻璃料、及軟化點較該第W璃料高以上之 P«料’而抑制玻璃料於受光面電極3與半導體基板i 161504.doc 201240936 之界面處之過度流動。並且’如上述般一方面藉由第1玻 璃料使玻璃成分適度地流動’確保上述界面處之接著性， 促進抗反射膜之分解、去除，而確保燒透性，另一方面利 用第2玻璃料抑制玻璃成分於上述界面處之過度流動藉 此可防止pn接面被破壞，且抑制並聯電阻下降而避免開路 電壓Voc下降，從而可獲得較高之轉換效率。 此處’將第2玻璃料之軟化點TS2與第1玻璃料之軟化點 Ts丨之差設為至少20°C以上之原因在於：若兩者之軟化點差 ATs未達20 C，則兩者之軟化點差^Ts變小，因此與使導電 性糊中含有1種玻璃料之情形無顯著差異，無法穩定地獲 得較高之轉換效率。 再者’第1及第2玻璃料之軟化點TSl、TS2只要於通常所 使用之玻璃料之間可確保兩者之軟化點差ATs為2(rc以 上，則並無特別限定，但為於更廣之煅燒溫度區域内獲得 所需之高轉換效率，較佳為第1玻璃料為5丨〇〜57〇。匸，第2 玻璃料為530〜680°C。 (2) B2〇3相對於Si02之莫耳比率α/β 玻璃包含非晶質化且形成網狀之網絡構造之網狀氧化 物、將網狀氧化物改質而進行非晶質化之改質氧化物及 兩者之中間之中間氧化物。其中’ Si〇2及1〇3均作為網狀 氧化物而發揮作用且為重要之構成成分。 並且’於太陽能電池之電極形成用導電性糊中’於導電 膜之煅燒時導電性粉末溶解於玻璃料中，該溶解之導電性 粉末於半導體基板1上被還原’而以金屬粒子之形式析 16I504.doc 12·Ts2 — Tsi ^ 20 (1) α/β$0.4 (2) l/4^x/y ^4/1 (3) where Ts is the softening point of the first frit, Ts2 is the softening point of the second glass frit, α is the amount of moles contained in each of the glass frits, and p is the molar amount of the Si 〇 2 in each glass frit 'x is the weight of the first frit, ^ is the weight of the second glass frit. That is, the conductive paste of the present invention contains two kinds of non-lead glass frits having at least B and Si and different softening points. The softening point Ts2 of the second glass frit is 20 C or more than the softening point Tsi of the first glass frit. The molar ratio α/β of 〇3 to Si〇2 is set to 0.4 or less, and the weight ratio x/y of the first glass frit and the second glass frit is set to 1/4 to 4/1. Thereby, even if calcination is carried out in a wide temperature range, good burntability can be ensured, and a solar cell having a high conversion efficiency of 161504.doc -10 201240936 can be stably obtained. The following description will be made on the reason that the glass frit satisfies the above formulas (1) to (3). (1) The softening point of the first and second glass frits is 3丨, and the glass batter of the si B Bi Ba system having 3 S1〇2, B2〇3, Bi2〇3, 83〇 has good fire-through property. Therefore, it is expected to be a substitute for the wrong glass frit. Further, since the glass frit having a lower softening point in the Si-B-Bi-Ba-based glass frit is: 3⁄4• burned through the private valley, it is easy to flow at the interface between the party smooth surface electrode 3 and the semiconductor substrate (n-type semiconductor layer la) It promotes the decomposition and removal of the anti-reflection film, and thus contributes to the improvement of the fire-through property. Further, the adhesion strength between the light-receiving surface electrode 3 and the semiconductor substrate 1 can be improved. On the other hand, the non-lead glass frit having a low softening point excessively flows at the interface between the conductive film to be the light-receiving electrode 3 and the semiconductor substrate, and diffuses toward the semiconductor substrate 1 side to rot the semiconductor substrate t. As a result, the tantalum joint formed between the crystallization of the n-type semiconductor layer type semiconductor is broken, and the desired high conversion efficiency cannot be obtained. Further, when the conductive powder is excessively diffused to the side of the semiconductor substrate 1 via the glass frit, the parallel resistance is lowered, and as a result, the voltage at the time of opening the output terminal, that is, the open circuit voltage V〇C is lowered, the result cannot be obtained. High conversion efficiency. In the present embodiment, the first glass frit having a lower softening point and the P« material having a softening point higher than the first glass material are contained in the conductive paste to suppress the glass frit on the light receiving surface. Excessive flow at the interface between the electrode 3 and the semiconductor substrate i 161504.doc 201240936. In addition, as described above, the glass component is appropriately flowed by the first glass frit, and the adhesion at the interface is ensured, and the decomposition and removal of the antireflection film are promoted to ensure the burnt property, and the second glass is used. The material suppresses excessive flow of the glass component at the above interface, thereby preventing the pn junction from being broken, and suppressing the decrease in the parallel resistance and avoiding the drop of the open circuit voltage Voc, thereby achieving high conversion efficiency. Here, the reason why the difference between the softening point TS2 of the second glass frit and the softening point Ts of the first glass frit is at least 20 ° C or more is that if the softening difference between the two is less than 20 C, the two Since the softening difference ^Ts is small, there is no significant difference from the case where one type of glass frit is contained in the conductive paste, and high conversion efficiency cannot be stably obtained. Further, the softening points TS1 and TS2 of the first and second glass frits are not particularly limited as long as the softening point difference ATs between the glass frits used is usually 2 (rc or more). The desired high conversion efficiency is obtained in a wider calcination temperature range, preferably 5 丨〇 to 57 第 for the first glass frit. 匸, 530 to 680 ° C for the second glass frit. (2) B2 〇 3 relative The molar ratio α/β of Si02 includes a network oxide which is amorphous and forms a network structure of a network, a modified oxide which is amorphized by upgrading the network oxide, and both An intermediate oxide in the middle, in which both 'Si〇2 and 1〇3 function as a network oxide and are important constituents. And 'in the conductive paste for forming an electrode for solar cells' is calcined in a conductive film. When the conductive powder is dissolved in the glass frit, the dissolved conductive powder is reduced on the semiconductor substrate 1 and is precipitated as metal particles. 16I504.doc 12·
201240936 出，藉此促進導電性粉末與半導體基板1之間之電性接觸 的形成。 然而’若B2〇3相對於Si〇2之莫耳比率α/β超過0 4，則 Βζ〇3之含有莫耳量變得過剩，雖導電性粉末向玻璃料中之 溶解量增加’但溶解於玻璃料中之導電性粉末變得難以於 半導體基板1上析出。其結果，大量之玻璃成分滯留於煅 燒後之受光面電極3與半導體基板丨之界面處，反而阻礙電 性接觸之形成。 因此，於本實施形態中，將ΙΑ相對於si〇2之莫耳比率 α/β設為0.4以下。 (3)第1玻璃料與第2玻璃料之重量比率x/y 藉由如上所述般使導電性糊中含有軟化點相差2〇亡以上 之2種非船系玻璃料（第1及第2玻璃料），可抑制玻璃料於受 光面電極3與半導體基板！之界面處之過度流動，從而可防 止pn接面被破壞，且可抑制並聯電阻之下降而避免開路電 壓Voc下降，並可獲得較高之轉換效率。 然而，於第1玻璃料與第2玻璃料之重量比率x/y未達"4 :情形時，過量地含有第2破璃料，另一方面，若上述重 量比率x/y超過4/卜則過量地含有第!玻璃料。 若如上述般任一玻璃料較另-破璃料大量地含有，則即 便兩者之玻璃料之軟化點存 ^ 廿隹20 C以上之差異，結果亦與 使導電性糊中含有1種#琏 .. 牙1玻璃枓之情形無顯著差異，而無法 穩定地獲得較高之轉換效率。 因此’於本實施形態中， 將弟1玻璃料與第2玻璃料之重 I6i504.doc -13· 201240936 量比率x/y設為1/4~4/1。 再者’玻璃料之總含量並無特別限定，較佳為相對於導 電性粉末100重量份為1〜6重量份。 如上所述’於本實施形態中，由於導電性糊中含有滿足 上述算式（1)〜（3)之玻璃料，故而一方面可藉由軟化點相對 較低之第1玻璃料確保接著性，另一方面可藉由軟化點較 第1玻璃料高20。(：之第2玻璃料抑制受光面電極與半導體基 板之間之過度的玻璃流動，藉此可防止pn接面被破壞，且 可抑制並聯電阻之下降而避免開路電壓v〇c下降。其結 果，雖為非鉛系導電性糊，但亦不會損及燒透性及電性接 觸性、接著強度等，且即便於較寬之溫度區域内進行煅 燒亦可穩定地獲得具有較高之轉換效率之太陽能電池。 再者，第1及第2玻璃料之構成成分只要含有y及b，則 並無特別限定，就獲得良好之電池特性之觀點而言，較佳 為上述Si-B-Bi-Ba系。並且，就各玻璃成分之組成而言， 於第1玻璃料中較佳為含有20〜40莫耳％之範圍之Bi2〇3、 2〇莫耳/〇之範圍之3&〇、及5莫耳％以下之範圍之A丨a〗， :第破璃料中較佳為含有5〜3〇莫耳％之範圍之別2〇3、 25莫耳/。之範圍之^〇、及5莫耳。以下之範圍之八丨2〇3。201240936, thereby promoting the formation of electrical contact between the conductive powder and the semiconductor substrate 1. However, if the molar ratio α/β of B2〇3 to Si〇2 exceeds 0 4, the molar content of Βζ〇3 becomes excessive, and the amount of dissolution of the conductive powder into the glass frit increases, but dissolves in The conductive powder in the glass frit becomes difficult to precipitate on the semiconductor substrate 1. As a result, a large amount of the glass component is retained at the interface between the calcined surface electrode 3 after calcination and the semiconductor substrate, and the formation of electrical contact is inhibited. Therefore, in the present embodiment, the molar ratio α/β of ΙΑ with respect to si 〇 2 is set to 0.4 or less. (3) Weight ratio of the first glass frit to the second glass frit x/y As described above, the conductive paste contains two kinds of non-vessel frits having a difference in softening point of 2 or more (1st and 1st) 2 glass frit), the glass frit can be suppressed on the light-receiving surface electrode 3 and the semiconductor substrate! The excessive flow at the interface prevents the pn junction from being broken, and suppresses the drop in the parallel resistance to avoid the drop of the open circuit voltage Voc, and can obtain a higher conversion efficiency. However, when the weight ratio x/y of the first glass frit and the second glass frit is less than "4", the second glass frit is excessively contained. On the other hand, if the above weight ratio x/y exceeds 4/ Bu contains an excess of frit! If any of the glass frits is contained in a large amount as in the above-mentioned glass frit, even if the softening point of the glass frit of the two materials is different from 20 C or more, the result is also such that one type of the conductive paste is contained.琏.. There is no significant difference in the case of the tooth 1 glass enamel, and it is not possible to stably obtain a high conversion efficiency. Therefore, in the present embodiment, the weight ratio I/i·I.i. Further, the total content of the glass frit is not particularly limited, but is preferably 1 to 6 parts by weight based on 100 parts by weight of the conductive powder. As described above, in the present embodiment, since the conductive paste contains the glass frit satisfying the above formulas (1) to (3), the first glass frit having a relatively low softening point can be ensured. On the other hand, the softening point can be 20 higher than that of the first glass frit. (The second glass frit suppresses excessive glass flow between the light-receiving surface electrode and the semiconductor substrate, thereby preventing the pn junction from being broken, and suppressing the decrease in the parallel resistance and preventing the decrease of the open-circuit voltage v〇c. Although it is a non-lead conductive paste, it does not impair the fire-through property, electrical contact property, adhesion strength, etc., and can stably obtain a high conversion even if it is calcined in a wide temperature range. The solar cell of the first and second glass frits is not particularly limited as long as it contains y and b, and is preferably Si-B-Bi from the viewpoint of obtaining good battery characteristics. -Ba. In addition, in the composition of each glass component, it is preferable that the first glass frit contains a range of 20 to 40 mol% of Bi2〇3, 2〇mol/〇3& And the range of 5 耳% or less of A丨a, : the first granules preferably contain 5 to 3 〇% of the range of 2 〇 3, 25 摩尔 /. And 5 moles. The following range is 8丨2〇3.
Bl2〇3作為改質氧化物具有調整玻璃流動性之作用，進 進义透〖生，因此於太陽能電池用之導電性糊中發揮重 要作用。 ' Bl2〇3具有降低軟化點之作用，因此若Bi203之含 莫耳量增加，則玻璃之軟化點過度地下降，&，變得易 I61504.doc 201240936 於結晶化。因此’於為軟化點較低之^破填料 =’ β12〇3之含有莫耳量較佳為2〇〜4〇莫耳。/。，於為要二較 第1玻璃枓南之軟化點之第2玻璃料之情形時， 有莫耳量較佳為5〜30莫耳％ 〇 23 3 又，BaO亦與Bi2〇3同樣地作為改質氧化物具有調 流動性之作用，亦有助於促進燒透性H Ba〇之人有 莫耳量係由與具有相同作用之％〇3之含有莫耳量之：聯 而決定，例如於為第!玻璃料之情形時，較佳為Μ莫耳 %，於為第2玻璃料之情形時，較佳為5〜25莫耳％。 再者’祕以外之驗土金屬氧化物，例如mJ〇、_、 Ca〇亦與_同樣地作為改質氧化物具有調整玻璃流動性 =作用’因此可加以使用，就獲得良好之燒透性之觀點而 舌’較佳為使用BaO。 又，Al2〇3作為中間氧化物發揮作用，藉由適量地含有 可抑制玻璃之結晶化’獲得穩定之非晶質麵，可提昇玻 螭料之化學耐久性。 然而，若含有Al2〇3之含有莫耳量超過5莫耳％，則反而 變侍易於結晶化’因此於含有八丨203之情形時，為5莫耳％ 以下’較佳為0· 1〜5莫耳％。 作為導電性粉末，只要為具有良好之導電性之金屬粉 末’則並無特別限冑，可較佳地使用即便於大氣中進行鍛 燒處理之情形時亦不會被氧化，而可維持良好之導電性之 Ag粉末。再者，該導電性粉末之形狀亦並無特別限定例 如可為球形狀、扁平狀、不定形形狀、或者該等之混合粉 161504.doc -15· 201240936 末。 又，導電性粉末之平均粒徑亦並無特別限定，就於導電 性粉末與半導體基板丨之間確保所需之接觸點之觀點而 S，以球形粉末換算計較佳為1〇〜5 〇pm。 又，較佳為於導電性糊申亦含有Znc^即，於導電性糊 之炮燒時，ZnO促進抗反射膜2之分解、去除而可順利地 進行燒透，從而降低受光面電極3與半導體基板丨之接觸電 阻。 有機媒劑係以黏合劑樹脂與有機溶劑例如以體積比率計 成為1〜3.7〜9之方式製備。再者，作為黏合劑樹脂，並無 特别限定，例如可使用乙基纖維素樹脂、硝酸纖維素樹 月曰丙烯馱系树脂、醇酸樹脂或該等之組合。又，對於有 :冷劑’亦並無特別限定，可單獨使用α·松脂醇、二甲 苯甲苯、—乙二醇單丁趟、二乙二醇單丁謎乙酸醋、二 醇單乙醚、—乙二醇單乙醚乙酸酯等，或者將該等組 合而使用。 又’亦較佳為於導電性糊中視需要添加鄰苯二甲酸二 (2.乙基己基）醋、鄰苯二甲酸二丁醋等塑化劑之】種或該等 亦較隹為添加脂肪酸醯胺或脂肪酸等流變調 整劑’進而亦可添加觸變劑、增黏劑、分散劑等。 :且：科電性糊可藉由如下方式容易地製造：以成為 疋之混合比率之方式秤量導電性粉末、第1及第2玻璃 ;'•一機媒齊j以及視需要之各種添加劑並加以混合且使 用三報研磨機等進行分散、混練。 161504.doc 201240936 如上所述，於本實施形態中，由於含有Ag粉末等導電性 粉末、第1及第2玻璃料及有機媒劑，且玻璃料滿足上述算 式⑴〜(3)，故而一方面可藉由軟化點相對較低之第！玻璃 料確保接著性，另-方面可藉由軟化點較^玻璃料高 20°C之第2玻璃料抑制受光面電極與半導體基板之間之過 度的玻璃流動，藉此即便於較寬之溫度區域内進行煅燒， 亦可確保良好之燒結性而穩^地獲得具有較高之轉換效率 之太陽能電池。 又，上述第1玻璃料含有2〇〜4〇莫耳％之範圍之出2〇3、 5〜20莫耳％之範圍之Ba〇、及5莫耳％以下之範圍之a丨办， 上述第2玻璃料含有5〜3〇莫耳％之範圍之則2〇3、卜乃莫耳 %之範圍之BaO、及5莫耳％以下之範圍之Al2〇3，藉此可獲 得燒透性及化學耐久性良好之導電性糊。 又 又’藉由含有Zn0,亦可促進燒透性，並可實現電極與 半導體基板之間之接觸電阻較低的太陽能電池。 並且，上述太陽能電池即便於較寬之溫度區域内進行煅 燒’亦穩定地成為具有較高之轉換效率者。 再者’本發明並不限定於上述實施形態。於上述實施形 態中，例示有含有Bi2〇ABa0之兩者之情形作為玻璃料之 較佳形‘態，由於兩者均為改質氧化物且促進燒透性，故而 亦可设為僅含有任一者之成分組成。 又，亦較佳為視需要使玻璃料中含有各種氧化物。例如 僅藉由使玻璃料中含有少量叫或⑽，便可飛躍性地提 昇玻璃之化㈣久性。然而’若大量地含有，則有發揮作 16l504.doc 17 201240936 為成核之作用之虞’因此於使玻璃料中含有該等们〇2或 2之清形時，其於玻璃料中之含量較佳為$莫耳％以 下。 又Ll2〇、Na2〇、κ2ο等鹼金屬氧化物與則2〇3同樣地具 有調整玻璃之軟化點之功能’因此亦較佳為適當地含有。 然而，若使玻璃料中大量地含有鹼金屬氧化物，則有玻璃 料之化子耐久性下降之虞，因此玻璃料中之驗金屬氧化物 之含量較佳為1〇莫耳。以下。 其次，具體地說明本發明之實施例。 [實施例1] [試樣之製作] (玻璃料之製作） 以按莫耳。/°計成為如表1之調配比率之方式調配Si〇2、 B2O3、Bi2〇3、Ba〇、ai2〇3，而製作玻璃料A〜L。並且， 使用 TG-DTA(Therm〇gravimetry-Differential Thermal 八响抓， 熱重量-示差熱分析裝置）進行熱分析’測定各玻璃料a〜l 之軟化點。即，於氧化鋁製容器中裝入試樣5 mg，且標準 >式樣使用α-氧化鋁，一面以流量1 mL/分鐘向測定裝置 内供給空氣’ 一面以如i分鐘上升2(rc之煅燒分佈對該測 定裝置進行加熱，根據相對於溫度之重量變化製作TG曲 線及DTA曲線。並且，根據該TG曲線及DTA曲線測定各試 樣之軟化點。 表1係表示玻璃料A〜L之成分組成、b203之含有莫耳量α 與Si〇2之含有莫耳量β的莫耳比率α/β(以下，記載為 161504.doc -18-Bl2〇3, as a modified oxide, has the effect of adjusting the fluidity of the glass, and it has an important role in the conductive paste for solar cells. 'Bel2〇3 has a function of lowering the softening point. Therefore, if the amount of Mo-containing content of Bi203 is increased, the softening point of the glass is excessively lowered, and it becomes easy to crystallize at I61504.doc 201240936. Therefore, the amount of the molar amount of the broken filler = 'β12〇3 which is lower in the softening point is preferably 2 〇 to 4 〇 mol. /. In the case of the second glass frit which is softer than the softening point of the first glass enamel, the molar amount is preferably 5 to 30 mol% 〇23 3 Further, BaO is also used as Bi2〇3. The modified oxide has a function of regulating the fluidity, and the person who contributes to the promotion of the fire-retardant H Ba〇 has a molar amount which is determined by the molar amount of the molar amount of 〇3 having the same effect, for example, In the case of the first glass frit, it is preferably Μ mol%, and in the case of the second glass frit, it is preferably 5 to 25 mol%. In addition, the soil metal oxides other than the secrets, such as mJ〇, _, and Ca〇, also have the effect of adjusting the glass fluidity as the modified oxide, and thus can be used, and good burntability is obtained. From the point of view, the tongue 'is preferably used BaO. Further, Al2〇3 acts as an intermediate oxide, and a stable amount of amorphous surface can be obtained by suppressing crystallization of glass, and the chemical durability of the glass material can be improved. However, if the content of Mox containing Al2〇3 exceeds 5 mol%, it will become easier to crystallize. Therefore, when it contains the case of gossip 203, it is 5 mol% or less, preferably 0·1~ 5 moles %. The conductive powder is not particularly limited as long as it is a metal powder having good conductivity, and can be preferably used without being oxidized even in the case of calcination in the atmosphere, and can be maintained in good condition. Conductive Ag powder. Further, the shape of the conductive powder is not particularly limited, and may be, for example, a spherical shape, a flat shape, an amorphous shape, or a mixture of the above-mentioned powders 161504.doc -15·201240936. Further, the average particle diameter of the conductive powder is not particularly limited, and it is preferably 1 〇 to 5 〇 pm in terms of spherical powder in terms of securing a desired contact point between the conductive powder and the semiconductor substrate. . Further, it is preferable that the conductive paste contains Znc, that is, when the conductive paste is fired, ZnO promotes decomposition and removal of the anti-reflection film 2, and can be smoothly burned, thereby reducing the light-receiving surface electrode 3 and The contact resistance of the semiconductor substrate. The organic vehicle is prepared in such a manner that the binder resin and the organic solvent are, for example, 1 to 3.7 to 9 in terms of a volume ratio. Further, the binder resin is not particularly limited, and for example, an ethyl cellulose resin, a nitrocellulose phenolic enamel resin, an alkyd resin or a combination thereof may be used. Further, there is no particular limitation on the presence of the "coolant", and α-rosinol, xylene toluene, ethylene glycol monobutyl hydrazine, diethylene glycol monobutyl vinegar acetate, diol monoethyl ether, and the like may be used alone. Ethylene glycol monoethyl ether acetate or the like, or used in combination. Further, it is also preferable to add a plasticizer such as bis(2.ethylhexyl) vinegar or butyl phthalate or the like to the conductive paste as needed. A rheology modifier such as a guanamine or a fatty acid may further be added with a thixotropic agent, a tackifier, a dispersant or the like. : and: the electro-chemical paste can be easily manufactured by weighing the conductive powder, the first and second glasses in a manner that becomes a mixing ratio of the crucible; - a machine-based medium and various additives as needed They are mixed and dispersed and kneaded using a three-stage grinder or the like. 161504.doc 201240936 As described above, in the present embodiment, the conductive powder such as Ag powder, the first and second glass frits, and the organic vehicle are contained, and the glass frit satisfies the above formulas (1) to (3). By softening the relatively low number! The glass frit ensures the adhesion, and the second glass frit having a softening point higher than the glass frit by 20 ° C can suppress excessive glass flow between the light-receiving surface electrode and the semiconductor substrate, thereby allowing a wide temperature. Calcination in the region also ensures good sinterability and stably obtains a solar cell having a high conversion efficiency. Further, the first glass frit contains a range of 2〇3, 5-20 mol% of Ba〇, and a range of 5 mol% or less in the range of 2〇4 to 4〇 mol%, and the above-mentioned first glass frit, The second glass frit contains Ba3 in the range of 5 to 3 mol%, BaO in the range of 2% by weight, and Al2〇3 in the range of 5 mol% or less, whereby the fire-through property can be obtained. And a conductive paste with good chemical durability. Further, by containing Zn0, the fire-through property can be promoted, and a solar cell having a low contact resistance between the electrode and the semiconductor substrate can be realized. Further, the above-mentioned solar cell is stably calcined even in a wide temperature range, and is stably converted to have a high conversion efficiency. Furthermore, the present invention is not limited to the above embodiment. In the above embodiment, the case where both of Bi2〇ABa0 are contained is exemplified as a preferred form of the glass frit. Since both of them are modified oxides and promote the fire-through property, they may be included only The composition of one component. Further, it is also preferred to contain various oxides in the glass frit as needed. For example, only by making a small amount of the glass frit or (10), the glass can be dramatically improved (4). However, if it is contained in a large amount, it will act as a nucleation effect of 16l504.doc 17 201240936. Therefore, when the glass frit contains the clear shape of these 2 or 2, its content in the glass frit. It is preferably less than or equal to $mole. Further, the alkali metal oxide such as Ll2〇, Na2〇, or κ2ο has a function of adjusting the softening point of the glass in the same manner as in the case of 2〇3. Therefore, it is preferably contained as appropriate. However, if the alkali metal oxide is contained in a large amount in the glass frit, the durability of the glass catalyst is lowered. Therefore, the content of the metal oxide in the glass frit is preferably 1 Torr. the following. Next, an embodiment of the present invention will be specifically described. [Example 1] [Production of sample] (Production of glass frit) To press Mohr. The glass particles A to L were prepared by blending Si〇2, B2O3, Bi2〇3, Ba〇, and ai2〇3 in the same manner as in Table 1. Further, the softening point of each of the glass frits a to l was measured by TG-DTA (Therm〇gravimetry-Differential Thermal, thermogravimetric-differential thermal analyzer). In other words, 5 mg of the sample was placed in an alumina container, and α-alumina was used in the standard >, and air was supplied to the measuring device at a flow rate of 1 mL/min. The calcination distribution was heated in the measurement apparatus, and a TG curve and a DTA curve were prepared based on the weight change with respect to temperature. The softening point of each sample was measured based on the TG curve and the DTA curve. Table 1 shows the glass frits A to L. The component composition, the molar ratio α of the b203 and the molar ratio α/β of the Si 〇2 containing the molar amount β (hereinafter, described as 161504.doc -18-
201240936 「B203/Si02」）、及軟化點Ts。 [表1] 玻璃料種類 玻璃組成(莫耳％) B2O3/S1O2 軟化點Ts Si02 B2〇3 Bi2〇3 BaO AI2O3 (-) (°C) A 32.8 12.8 36.7 16.9 0.8 0.39 515 B 37.7 11.7 31.9 18.3 0.4 0.31 536 C 38.8 12.1 32.9 15.7 0.5 0.31 542 D 41.2 12.8 34.9 10.6 0.5 0.31 — 547 E 44.5 12.5 25.0 17.6 0.4 0.28 567 F 52.5 14.6 19.0 12.2 1.7 0.28 597 G 51.8 13.0 16.3 17.3 1.6 0.25 613 Η 60.3 9.7 「19.3 9.0 1.7 0.16 640 I 62.5 10.1 16.4 9.4 1.6 0.16 659 J 66.3 6.5 16.3 9.3 1.6 0.10 673 K* 13.0 49.8 18.2 17.3 1.7 3.83 564 L* 19.7 49.0 10.5 19.1 1.7 2.49 618 *為本發明（技術方案丨）之範圍外 自該表1顯而易見，玻璃料A〜j2B2〇3/Si〇2為〇 4以下， 表示本發明範圍内之玻璃料組成。 與此相對，玻璃料K、L2B2〇3/Si〇2分別為383、2 49, 大幅地超過0.4，表示本發明範圍外之玻璃料組成。 於该實施例1中，使用該等玻璃料A〜L製作導電性糊， 進而使用該導電性糊製作太陽能電池單元，並評價特性。 (導電性糊之製作） 準備作為導電性粉末之平均粒徑為16㈣之球形够 末、及比表面積為10 W/g之Zn〇。 繼而，製作有機媒劑。即 維素樹脂成為1 〇重量％、作 9〇重量％之方式混合乙基纖 作有機媒劑。 ’以作為黏合劑樹脂之乙基纖 為有機溶劑之TEXANOL成為 維素樹脂與TEXANOL，而製 161504.doc •19· 201240936 繼而，以Ag粉末成為82.〇重量％、Zn〇成為45重量％、 玻璃料總計成為2.0重量％之方式將該等與脂肪酸醯胺或脂 肪酸等流變調整劑及有機媒劑—併進行調配，利用行星式 混合機進行混合後，利用三輕研磨機加以混練，藉此製作 試樣編號1〜16之導電性糊。 再者，$電性糊中所含有之玻璃料係以如表2所示般適 當地選擇玻璃料A〜J進行組合’並以總量成為2重量％之方 式加以調配。 (太陽能電池單元之製作） 藉由電漿辅助化學氣相沈積法（PECVD，Plasma Enhaneed201240936 "B203/Si02"), and softening point Ts. [Table 1] Glass composition Glass composition (mol%) B2O3/S1O2 Softening point Ts Si02 B2〇3 Bi2〇3 BaO AI2O3 (-) (°C) A 32.8 12.8 36.7 16.9 0.8 0.39 515 B 37.7 11.7 31.9 18.3 0.4 0.31 536 C 38.8 12.1 32.9 15.7 0.5 0.31 542 D 41.2 12.8 34.9 10.6 0.5 0.31 — 547 E 44.5 12.5 25.0 17.6 0.4 0.28 567 F 52.5 14.6 19.0 12.2 1.7 0.28 597 G 51.8 13.0 16.3 17.3 1.6 0.25 613 Η 60.3 9.7 "19.3 9.0 1.7 0.16 640 I 62.5 10.1 16.4 9.4 1.6 0.16 659 J 66.3 6.5 16.3 9.3 1.6 0.10 673 K* 13.0 49.8 18.2 17.3 1.7 3.83 564 L* 19.7 49.0 10.5 19.1 1.7 2.49 618 *Before the scope of the invention (technical solution) It is apparent in Table 1 that the glass frit A to j2B2 〇 3 / Si 〇 2 is 〇 4 or less, and represents the glass frit composition within the scope of the present invention. In contrast, the glass frit K, L2B2 〇 3 / Si 〇 2 are 383, 2, respectively. 49, substantially exceeding 0.4, indicating a glass frit composition outside the scope of the present invention. In the first embodiment, a conductive paste was prepared using the glass frits A to L, and a solar battery cell was produced using the conductive paste, and evaluated. Characteristics (conductivity Preparation) As a conductive powder, a spherical particle having an average particle diameter of 16 (four) and a Zn 比 having a specific surface area of 10 W/g were prepared. Then, an organic vehicle was prepared, that is, the vitamin resin was 1% by weight, and 9 was made. Ethyl fiber is used as an organic vehicle in the form of 5% by weight. 'TEXANOL, which is an organic solvent as a binder resin, is made into a vitamin resin and TEXANOL, and 161504.doc •19·201240936, followed by Ag powder The mixture is blended with a rheology modifier such as a fatty acid guanamine or a fatty acid, and an organic vehicle, and is blended in a planetary mixture, such as 82% by weight, Zn〇, and 45% by weight. After mixing, the machine was kneaded by a three-light grinder to prepare a conductive paste of sample Nos. 1 to 16. Further, the glass frit contained in the electric paste was suitably as shown in Table 2. The glass frits A to J were selected for combination ', and the total amount was adjusted to 2% by weight. (Manufacture of solar cells) by plasma assisted chemical vapor deposition (PECVD, Plasma Enhaneed)
Chemical Vapor Dep〇siti〇n)，於長 5〇 爪爪、寬 5〇 出爪、厚 0.2 mm之單晶之Si系半導體基板之整個表面形成膜厚〇ι μπι之抗反射膜。再者，該以系半導體基板係藉由使p擴散 至Ρ型以系半導體層之一部分中，而於Ρ型Si系半導體層之 上表面形成n型Si系半導體層。 其次’準備以A1為主成分之A1糊及以Ag為主成分之Ag 糊。繼而’將A1糊及Ag糊適當地塗佈於上述Si系半導體基 板之背面’並使其乾燥而形成背面電極用導電膜。 Μ而’使用上述導電性糊進行絲網印刷，以煅燒後之膜 厚成為20 μιη之方式將導電性糊塗佈於si系半導體基板之 表面’而製作受光面電極用導電膜。 繼而’將各試樣放入溫度設定成15〇t：之烘箱中，使導 電膜乾燥。 其後’使用輸送帶式近紅外爐（Despatch公司製造， 161504.doc • 20- 201240936 CDF7210)，以花費約1分鐘於入口〜出口間搬送試樣之方 式調整搬送速度，於大氣環境下以煅燒最高溫度 760〜80(TC進行煅燒’製作導電性糊燒結而形成有受光面 電極之試樣編號1〜1 6之太陽能電池單元。再者，將炮燒最 高溫度設為760〜800°C之原因在於最適合之煅燒最高溫度 根據糊組成而不同。 [試樣之評價] 對於試樣編號1〜16之各試樣，使用太陽模擬器（英弘精 機公司製造 ’ SS-5 0XIL)，於溫度25。(：、AM(Air Mass，空 氣團）-1.5之條件下測定電流-電壓特性曲線，根據該電流_ 電壓特性曲線求出算式（4)所示之填充因數ff(Fill Factor)。 FF=Pmax/(Voc xlsc) ... (4) 此處，Pmax為試樣之最大輸出，v〇c為開路電壓，isc為 短路電流。 又，由最大輸出pmax、受光面電極之面積A、放射照度 E，基於算式（5)求出轉換效率η。 n=Pmax/(AxE) …(5) 表2係表示試樣編號丨〜16之各試樣之糊組成、玻璃料之 軟化點差ΔΤ3、填充因數FF及轉換效率η。 161504.doc -21 · 201240936 [表2] 試樣 No. 糊組成(重量％) 軟化點差 △Ts (°C) 填充因 數FF ㈠ 轉換效 率η (%) Ag ZnO 玻璃料 有機媒劑、 其他 1 82.0 4.5 2.0 (A/F=l.0/1.0) 11.5 82 0.772 16.51 2 82.0 4.5 2.0 (A/J=l.0/1.0) 11.5 158 0.781 16.71 3 82.0 4.5 2.0 (B/G=l.0/1.0) 11.5 77 0.775 16.58 4 82.0 4.5 2.0 (B/I=l.0/1.0) 11.5 123 0.770 16.47 5 82.0 4.5 2.0 (C/H=l.0/1.0) 11.5 98 0.765 16.36 6 82.0 4.5 2.0 (C/J=l.0/1.0) 11.5 131 0.771 16.49 7 82.0 4.5 2.0 (D/I=l.0/1.0) 11.5 112 0.783 16.75 8 82.0 4.5 2.0 (E/F=l.0/1.0) 11.5 30 0.765 16.36 9 82.0 4.5 2.0 (E/H=l.0/1.0) 11.5 73 0.781 16.71 10 82.0 4.5 2.0 (A/B=l.0/1.0) 11.5 21 0.768 16.43 11 82.0 4.5 2.0 (C/E=l.0/1.0) 11.5 25 0.769 16.45 12** 82.0 4.5 2.0 (F/H=l.0/1.0) 11.5 43 0.767 16.41 13* 82.0 4.5 2.0 (C) 11.5 0 0.751 16.06 14* 82.0 4.5 2.0 (C/D=l.o/i.o) 11.5 5 0.755 16.15 15* 82.0 4.5 2.0 (C/K=l.〇/l.(D 11.5 22 0.634 13.56 16* 82.0 4.5 2.0 (£/L=l.0/1.0) 11.5 51 0.645 13.80 *為本發明（技術方案1)之範圍外 **為本發明（技術方案2)之範圍外 可知試樣編號B之導電性糊中僅含有軟化㈣為⑽ 之玻璃料C，轉換效率η降低為16 〇6%。 試樣編號14之導電性糊中雖含有玻璃料c、d，但軟化 161504.doc -22. 201240936 點差ATs較小為5°c(玻璃料c : 542°C，玻璃料D : 547。〇， 雖與僅含有1種玻璃料之試樣編號12相比轉換效率η稍有提 昇’但轉換效率η仍較低為1 6.1 5%，無法獲得充分之轉換 效率η。 試樣編號15中’雖軟化點差aTs為22°c，有汕^以上之 差異’但由於含有32〇3/以〇2為3.83之本發明範圍外之玻璃 料K ’故而轉換效率大幅下降為13 56%。認為其係由於含 有B2〇3/Si〇2較大之玻璃料K，故而大量之熔融玻璃滯留於 受光面電極與半導體基板之界面處，因此接觸電阻增大， 其結果，轉換效率η下降。 s式樣編號16中，雖軟化點差ATs為51。〇,有2〇β(：以上之 差異，但由於含有82〇3/8丨〇2為2.49之本發明範圍外之玻璃 料L故而基於與試樣編號1 5相同之理由，轉換效率η下降 為 13.80%。 與此相對’可知試樣編號1〜12中，組合使用軟化點差 △Ts為20 C以上之2種玻璃料，且使用B2〇3/si〇2亦為 0.10 0.39之玻璃料A〜j，並且各玻璃料之調配比率亦為 1 /1 * 因此轉換 jHr ^ r\ tV a ι ' r'成為16.36〜16.75%，可獲得具有 16.35%以上之較咼轉換效率，之太陽能電池。再者，試樣 編號12中’雖第1玻壤料之軟化點為飢，超過m 為高溫’但於將煅燒最高溫度調整成最適合之情形時，可 獲得所需之較高轉換效率η。 [實施例2] 之破續料Ε 使用實施例1中製作 F及Η ’以成為如表3所 161504.doc •23· 201240936 示之糊組成之方式藉由與實施例1相同之方法、步驟製作 試樣編號21〜24之導電性糊。 繼而，於780〜820。(：之間將煅燒最高溫度分別設定為4種 不同溫度進行煅燒，除此以外，藉由與實施例丨相同之方 法步驟製作試樣編號21〜24之太陽能電池單元。 並且’對於各試樣’藉由與實施例1相同之方法、步驟 測定填充因數FF及轉換效率η。 &表3係表不試樣編號21〜24之各試樣之糊組成、煅燒溫度 k 7最阿溫度）、填充因數FF及轉換效率η、判定結果。 判定結果中’將轉換效率η為1 6.35%以上之試樣設 (。格），將轉換效率未達16 35%之試樣設為χ(不合 格）。 [表3] 試樣 Γ*— 糊組成(重量％) 埴奋IS -- No. Ag Zn〇 玻璃料 有機媒 溫度 數FF 率η 判定 E F Η —--- ---- CC) (-) (%) 21 82.0 780 0.778 16.64 〇 4.5 1.0 - 1.0 Π.5 790 0.781 16.71 〇 800 0.779 16.66 〇 ----^. '--- — 810 0.770 16.47 〇 22* * 82.0 4.5 780 0.650 13.90 X - 1.0 1.0 11.5 790 0.767 16.41 〇 800 0.767 16.41 〇 — 01 Λ λ niia r\ ------- OlU ν· /00 lO.io U 23* 82.0 4.5 2.0 770 0.650 13.90 X Π.5 780 0.743 15.89 X --- 790 0.730 15.61 X 24* 82.0 790 0.621 13.28 X 4.5 • - 2.0 11.5 800 0.746 15.96 X 810 0.779 16.66 〇 -----1 — 820 0.740 15.83 X ------- I6I504.docChemical Vapor Dep〇siti〇n), an anti-reflection film having a thickness of 〇ι μπι is formed on the entire surface of a Si-based semiconductor substrate having a length of 5 爪 claws, a width of 5 〇 claws, and a thickness of 0.2 mm. Further, in the semiconductor substrate, an n-type Si-based semiconductor layer is formed on the upper surface of the bismuth-based Si-based semiconductor layer by diffusing p into a portion of the bismuth-based semiconductor layer. Next, 'A1 paste containing A1 as a main component and Ag paste containing Ag as a main component are prepared. Then, the A1 paste and the Ag paste are appropriately applied to the back surface of the Si-based semiconductor substrate and dried to form a conductive film for a back surface electrode. In the same manner, the conductive paste was used for screen printing, and the conductive paste was applied to the surface of the Si-based semiconductor substrate so that the film thickness after firing was 20 μm, thereby producing a conductive film for the light-receiving surface electrode. Then, each sample was placed in an oven set to a temperature of 15 Torr to dry the conductive film. Then, using a conveyor-type near-infrared furnace (manufactured by Despatch Co., Ltd., 161504.doc • 20-201240936 CDF7210), the conveying speed was adjusted by transferring the sample between the inlet and the outlet in about 1 minute, and calcined in an atmospheric environment. The maximum temperature is 760 to 80 (the TC is calcined) to prepare a solar cell in which the conductive paste is sintered to form the sample No. 1 to 16 of the light-receiving surface electrode. Further, the maximum temperature of the shot is set to 760 to 800 ° C. The reason is that the highest temperature for the most suitable calcination varies depending on the paste composition. [Evaluation of the sample] For each sample of sample Nos. 1 to 16, a solar simulator (SS-5 0XIL manufactured by Yinghong Seiki Co., Ltd.) was used at the temperature. 25. The current-voltage characteristic curve is measured under the condition of (:, AM (Air Mass)-1.5, and the fill factor ff (Fill Factor) shown in the formula (4) is obtained from the current_voltage characteristic curve. =Pmax/(Voc xlsc) (4) Here, Pmax is the maximum output of the sample, v〇c is the open circuit voltage, isc is the short-circuit current, and the maximum output pmax, the area A of the light-receiving surface electrode, Radiation illuminance E, based on equation (5) Conversion efficiency η n=Pmax/(AxE) (5) Table 2 shows the paste composition of each sample of sample Nos. 丨16, the softening point difference ΔΤ3 of the glass frit, the filling factor FF, and the conversion efficiency η. .doc -21 · 201240936 [Table 2] Sample No. Paste composition (% by weight) Softening point difference ΔTs (°C) Filling factor FF (I) Conversion efficiency η (%) Ag ZnO glass frit organic vehicle, other 1 82.0 4.5 2.0 (A/F=l.0/1.0) 11.5 82 0.772 16.51 2 82.0 4.5 2.0 (A/J=l.0/1.0) 11.5 158 0.781 16.71 3 82.0 4.5 2.0 (B/G=l.0/1.0 11.5 77 0.775 16.58 4 82.0 4.5 2.0 (B/I=l.0/1.0) 11.5 123 0.770 16.47 5 82.0 4.5 2.0 (C/H=l.0/1.0) 11.5 98 0.765 16.36 6 82.0 4.5 2.0 (C/ J=l.0/1.0) 11.5 131 0.771 16.49 7 82.0 4.5 2.0 (D/I=l.0/1.0) 11.5 112 0.783 16.75 8 82.0 4.5 2.0 (E/F=l.0/1.0) 11.5 30 0.765 16.36 9 82.0 4.5 2.0 (E/H=l.0/1.0) 11.5 73 0.781 16.71 10 82.0 4.5 2.0 (A/B=l.0/1.0) 11.5 21 0.768 16.43 11 82.0 4.5 2.0 (C/E=l.0 /1.0) 11.5 25 0.769 16.45 12** 82.0 4.5 2.0 (F/H=l.0/1.0) 11.5 43 0.767 16.41 13* 82.0 4.5 2.0 (C) 11.5 0 0.751 16.06 14* 82.0 4.5 2.0 (C/D=lo/io) 11.5 5 0.755 16.15 15* 82.0 4.5 2.0 (C/K=l.〇/l.(D 11.5 22 0.634 13.56 16* 82.0 4.5 2.0 (£/L=l.0 /1.0) 11.5 51 0.645 13.80 * is outside the scope of the present invention (claim 1). ** Beyond the scope of the present invention (claim 2), it is understood that the conductive paste of sample No. B contains only glass which is softened (four) is (10) Material C, the conversion efficiency η was reduced to 16 〇 6%. The conductive paste of sample No. 14 contained glass frit c and d, but softened 161504.doc -22. 201240936 The spread ATs was as small as 5 ° C (glass frit c: 542 ° C, frit D: 547). 〇, although the conversion efficiency η is slightly improved compared to sample No. 12 containing only one type of glass frit, 'the conversion efficiency η is still low at 16.1 5%, and sufficient conversion efficiency η cannot be obtained. Sample No. 15 'Although the softening point difference aTs is 22°c, there is a difference of 汕^ or more, but the conversion efficiency is greatly reduced to 13 56% due to the glass frit K' containing 32〇3/3.82 which is outside the scope of the present invention. Since the glass frit K having a large B2〇3/Si〇2 is contained, a large amount of molten glass is retained at the interface between the light-receiving surface electrode and the semiconductor substrate, so that the contact resistance is increased, and as a result, the conversion efficiency η is lowered. In the s designation No. 16, the softening point difference ATs is 51. 〇, there is a difference of 2 〇 β (: the above, but the glass frit L outside the scope of the present invention containing 82 〇 3/8 丨〇 2 is 2.49 is based on The conversion efficiency η decreased to 13.80% for the same reason as the sample No. 15. In contrast, the sample number 1 was known. In 12, two kinds of glass frits having a softening point difference ΔTs of 20 C or more are used in combination, and B2〇3/si〇2 is also used as a glass frit A~j of 0.10 0.39, and the ratio of each glass frit is also 1 /1 * Therefore, the conversion jHr ^ r\ tV a ι ' r' becomes 16.36 to 16.75%, and a solar cell having a higher conversion efficiency of 16.35% or more can be obtained. Further, in sample No. 12, 'the first glass The softening point of the loam is hunger, and m is higher than 'high temperature'. However, when the maximum calcination temperature is adjusted to the most suitable condition, the required higher conversion efficiency η can be obtained. [Example 2] Residual material Ε Implementation In the example 1, F and Η were produced in the same manner as in Example 1 except that the composition of the paste was as shown in Table 3, 161504.doc • 23·201240936. The conductive paste of sample Nos. 21 to 24 was produced. Then, solar cells of sample Nos. 21 to 24 were produced by the same method steps as in Example 于, except that the maximum calcination temperature was set to four different temperatures for calcination. And 'for each sample' by the same method as in the first embodiment, The filling factor FF and the conversion efficiency η were measured. & Table 3 shows the paste composition of each sample of sample Nos. 21 to 24, the calcination temperature k 7 the most temperature, the filling factor FF, the conversion efficiency η, and the determination result. In the judgment result, 'the sample with the conversion efficiency η of 1 6.35% or more is set to (the grid), and the sample with the conversion efficiency of less than 16 35% is set to χ (failed). [Table 3] Sample Γ* — Paste composition (% by weight) Hyper IS -- No. Ag Zn〇 glass frit organic medium temperature number FF rate η judge EF - —- ----- ---- CC) (-) (%) 21 82.0 780 0.778 16.64 〇4.5 1.0 - 1.0 Π.5 790 0.781 16.71 〇800 0.779 16.66 〇----^. '--- 810 0.770 16.47 〇22* * 82.0 4.5 780 0.650 13.90 X - 1.0 1.0 11.5 790 0.767 16.41 〇800 0.767 16.41 〇— 01 Λ λ niia r\ ------- OlU ν· /00 lO.io U 23* 82.0 4.5 2.0 770 0.650 13.90 X Π.5 780 0.743 15.89 X --- 790 0.730 15.61 X 24* 82.0 790 0.621 13.28 X 4.5 • - 2.0 11.5 800 0.746 15.96 X 810 0.779 16.66 〇---- -1 — 820 0.740 15.83 X ------- I6I504.doc
*24· 201240936 *為本發明（技術方案1 )之範圍外 * *為本發明（技術方案2 )之範圍外 可知試樣編號23中，導電性糊中僅含有軟化點Ts為 567 C之玻璃料E，因此轉換效率η均低至， 並且根據煅燒溫度之不同，轉換效率^產生不均。 又，試樣編號24中，導電性糊，僅含有軟化點 65η：之玻璃料η，因此雖於锻燒溫度為8邮之情形時， 可獲仵16.66%之良好之轉換效率”，但於其他锻燒溫度 下，轉換效率η低至13.28〜15.96%。，可知雖於最適合 之瓜U下可獲仔良好之轉換效率η，但根據煅燒溫度 之不同’轉換效率η產生不均。 如上所述，可知於僅含有1種玻璃料之情形時，轉換效 率n之由锻燒溫度引起之不均較大，無法於較寬之炮燒溫 度區域内穩定地獲得所需之較高轉換效率η。 與此相對’可知試樣編號21中，使用軟化點差—為 73t之玻璃料E、h，AB2(Vsic>2均狀仏下，並且2種玻 璃料之調配比率亦為1/1，因此可於煅燒最高溫度為 780〜810C之較寬之溫度範圍内獲得具有16 47〜16 6㈣之 較南轉換效率η之太陽能電池。 又，試樣編號22中，使用軟化點差么^為43<t之玻璃料 F、H’ AB2〇3/Si〇2均為〇.4以下，又，2種玻璃料之調配 比率亦為1/1，且第1玻璃料之軟化點為597芯，超過 57〇°C，因此若煅燒溫度下降為了如工’則轉換效率^下降 為13.90%。即，可知於第i玻璃料之軟化點過高之情形 161504.doc -25· 201240936 時’用以獲得高轉換效率之煅燒溫度區域雖較 〇 及24寬’但較試樣編號21稍窄。 ，扁號 [實施例3] 使用實施例1中製作之玻璃料A及J，以成為如表4所厂、之 糊組成之方式藉由與實施例、相同之方法、步驟製=== 編號3 1〜39之導電性糊及太陽能電池單元。 並且，對於各試樣，藉由與實施例丨相同之方法、步驟 測定填充因數FF及轉換效率η。 表4係表示試樣編號31〜39之各試樣之糊組成、玻璃料a 與玻璃料J之重量比率x/y(以下，記載為「A/J」）、填充因 數FF及轉換效率η。 [表4] 試料 No. 31 糊組点(重量 A/J ㈠ 0.25 填充因數FF (-) 0.765 轉換效率η (%) Ag 82.0 ZnO 4.5 玻璃料 士 .Uf sis.l «· A 0.4 J 1.6 有機係劑、其他 11.5 5Z 33 ~34~ 35 36 82.0 82.0 82.0 82.0 82.0 4.5 4.5 ~ΤΓ 4.5 4.5 0.6 0.8 Τ〇~ 1.2 14 1.4 1.2 IT 0.8 0 6 11.5 11.5 ΪΪ3 11.5 11 < 0.43 0.67 Too 1.50 0.768 0.773 ~~0?78Ϊ 0.775 10.JO 16.43 16.53 16.71 16.58 37 38* 82.0 82.0 4.5 4.5 1.6 1.8 0.4 0.2 11.3 11.5 11.5 2.33 4.00 9.00 0.770 0.769 0.741 16.47 16.45 15 85 39不 82.0 4,5 U.2 1.8 11.5 0.11 0.755 16.15 *為本發明（技術方案1)之範圍外 試樣編號38中，A/J較大為9〇〇，且軟化點較低之玻璃料 A之含里過剩’因此轉換效率^下降為1585〇/。。認為其原 因在於：由於過量地含有軟化點較低之玻璃料A，故而於 瓜:^時’於應成為受光面電極之導電膜與半導體基板之界 161504.doc 201240936 面處發生玻璃成分之過度流動，該玻璃成分過度地腐蝕半 導體基板，並且熔融玻璃經由Ag過度地擴散至半導體基 板，導致並聯電阻之下降，而開路電壓V〇e下降，其結果 無法獲得較高之轉換效率η。 另一方面，試樣編號39中，A/J較小為〇11，且軟化點較 鬲之玻璃料J之含量過剩，因此轉換效率”下降為16•丨5%。 認為其原因在於：由於過量地含有軟化點較高之玻璃料 J，故而雖於應成為受光面電極之導電膜與半導體基板之 界面處不會發生玻璃成分之過度流動，但玻 浮於受光面電極之表面，導致接著強度之下降，結= 效率下降》 與此相對，試樣編號3卜37中A/J為〇 25〜4 〇(1/4〜4/丨）之 本發明範圍内’因此可獲得轉換效率”高至16 36〜i67i% 之太陽能電池。 [產業上之可利用性] 即便使用，亦可於較寬之㈣溫度區域 内穩定地獲得具有所需之較高轉換效率之太陽能電池。 【圖式簡單說明】 圖1係表示使用本發明之導電性糊而製造之太陽能電池 之一實施形態的主要部分剖面圖。 圖2係模式性地表示受光面電極側之放大平面圖。 圖3係模式性地表示背面電極側之放大仰視圖。 【主要元件符號說明】 1 半導體基板 16I504.doc -27· 201240936 la n型半導體層 lb P型半導體層 2 抗反射膜 3 受光面電極（電極） 4 背面電極 5a 指狀電極 5b 指狀電極 5n 指狀電極 6 母線電極 7 集電電極 8 提取電極 161504.doc • 28 ·*24· 201240936 *Beside the scope of the present invention (claim 1) * * In the sample No. 23 of the present invention (Technical Solution 2), the conductive paste contains only glass having a softening point Ts of 567 C Material E, therefore, the conversion efficiency η is as low as, and depending on the calcination temperature, the conversion efficiency is uneven. Further, in sample No. 24, since the conductive paste contained only the glass frit η of the softening point 65η, when the calcination temperature was 8, a good conversion efficiency of 16.66% was obtained, but At other calcination temperatures, the conversion efficiency η is as low as 13.28 to 15.96%. It is known that although the conversion efficiency η is good at the most suitable melon U, the conversion efficiency η varies depending on the calcination temperature. In the case where only one type of glass frit is contained, the unevenness of the conversion efficiency n caused by the calcination temperature is large, and the desired high conversion efficiency cannot be stably obtained in a wide range of the calcination temperature. η. In contrast, in the sample No. 21, the glass frit E, h, AB2 (Vsic > 2) in which the softening point difference was 73 t was used, and the blending ratio of the two kinds of frits was also 1/1. Therefore, a solar cell having a souther conversion efficiency η of 16 47 to 16 6 (d) can be obtained in a wide temperature range in which the maximum temperature of calcination is 780 to 810 C. Further, in sample No. 22, the softening point difference is used. 43<t glass frit F, H' AB2〇3/Si〇2 are both 〇.4 Moreover, the blending ratio of the two kinds of glass frit is also 1/1, and the softening point of the first frit is 597 cores, exceeding 57 〇 ° C. Therefore, if the calcination temperature is lowered, the conversion efficiency is lowered to 13.90. %. That is, it can be seen that the softening point of the i-th glass frit is too high. 161504.doc -25· 201240936 'The calcination temperature region for obtaining high conversion efficiency is thinner than 24 width' but slightly smaller than sample No. 21. Narrow. Flat No. [Example 3] The glass frits A and J prepared in Example 1 were used to form a paste composition as shown in Table 4 by the same method and procedure as in the example == = Conductive paste and solar cell No. 3 1 to 39. Further, for each sample, the filling factor FF and the conversion efficiency η were measured by the same method and procedure as in Example 表. Table 4 shows the sample number 31. The paste composition of each sample of ～39, the weight ratio x/y of the glass frit a and the glass frit J (hereinafter referred to as "A/J"), the filling factor FF, and the conversion efficiency η. [Table 4] Sample No. 31 Paste point (weight A/J (one) 0.25 fill factor FF (-) 0.765 conversion efficiency η (%) Ag 82.0 ZnO 4.5 Glass material.Uf sis.l «· A 0.4 J 1.6 Organic agent, other 11.5 5Z 33 ~34~ 35 36 82.0 82.0 82.0 82.0 82.0 4.5 4.5 ~ΤΓ 4.5 4.5 0.6 0.8 Τ〇~ 1.2 14 1.4 1.2 IT 0.8 0 6 11.5 11.5 ΪΪ3 11.5 11 < 0.43 0.67 Too 1.50 0.768 0.773 ~~0?78Ϊ 0.775 10.JO 16.43 16.53 16.71 16.58 37 38* 82.0 82.0 4.5 4.5 1.6 1.8 0.4 0.2 11.3 11.5 11.5 2.33 4.00 9.00 0.770 0.769 0.741 16.47 16.45 15 85 39 不 82.0 4,5 U.2 1.8 11.5 0.11 0.755 16.15 * In the sample No. 38 outside the scope of the invention (claim 1), the glass having a large A/J of 9 〇〇 and a lower softening point Material A has a surplus of excess 'so the conversion efficiency ^ drops to 1585 〇 /. . It is considered that the reason is that since the glass frit A having a low softening point is excessively contained, the glass component is excessively formed at the surface of the conductive film and the semiconductor substrate which should be the surface of the light-receiving surface, 161504.doc 201240936. Flowing, the glass component excessively corrodes the semiconductor substrate, and the molten glass excessively diffuses to the semiconductor substrate via Ag, resulting in a decrease in the parallel resistance and an decrease in the open circuit voltage V〇e, with the result that a high conversion efficiency η cannot be obtained. On the other hand, in sample No. 39, A/J was as small as 〇11, and the softening point was excessively higher than that of the glass frit J, so the conversion efficiency was decreased to 16•丨5%. Excessively containing the glass frit J having a high softening point, the glass component does not excessively flow at the interface between the conductive film to be the light-receiving electrode and the semiconductor substrate, but the glass floats on the surface of the light-receiving electrode, resulting in subsequent The decrease in the strength, the knot = the decrease in the efficiency. In contrast, in the sample No. 3, the A/J is 〇25 to 4 〇 (1/4 to 4/丨) within the scope of the present invention, and thus the conversion efficiency can be obtained. Up to 16 36~i67i% of solar cells. [Industrial Applicability] Even if it is used, it is possible to stably obtain a solar cell having a desired high conversion efficiency in a wide (four) temperature region. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a cross-sectional view showing a principal part of an embodiment of a solar cell produced by using the conductive paste of the present invention. Fig. 2 is an enlarged plan view schematically showing the side of the light-receiving surface electrode. Fig. 3 is a schematic enlarged plan view showing the back electrode side. [Description of main components] 1 Semiconductor substrate 16I504.doc -27· 201240936 la n-type semiconductor layer lb P-type semiconductor layer 2 anti-reflection film 3 light-receiving electrode (electrode) 4 back electrode 5a finger electrode 5b finger electrode 5n Electrode 6 bus electrode 7 collector electrode 8 extraction electrode 16150.doc • 28 ·