201044620 六、發明說明： 【發明所屬之技術領域】 本發明係關於一種修復太陽能基板電極變色瑕疫的方法，尤指一 種免用化學藥劑修復太陽能基板電極變色的方法。 【先前技術】 〇 目前太陽能電池之型式主要可分為晶體矽和非晶矽兩大類。一般 來說，在晶體矽的材料中，矽原子具有高度的周期性排列，因此， •晶體矽太陽能電池的光電轉換效率最高，且穩定性也比較好。對於 非晶矽的太陽能電池來說，由於其製作方法通常是用電漿式化學氣 相沈積法’在基板上長成非晶矽的薄膜，因此其製作方式較單晶矽 和夕曰曰石夕太陽能電池簡單’生產速度也最快，但是非晶石夕的太陽能 電池的轉換效率較晶體石夕太陽能電池為低。因此，目前市面上應用 最普遍的，是以晶體矽太陽能電池為主。 ❹—般來說’單體㈣製妨式通常是㈣為補製作形成石夕晶 片，作為太陽能f池之基板。接著切晶以摻誠擴散微量硼、 構等摻雜物，以於晶圓上形成p_n結構。並且在石夕晶片表面形成一 抗反射層，之後在石夕晶片的正面和背面形成金屬電極。前述的抗反 射層通常是使魏⑽顧沉積製程而形成，而金屬電極則是使用 混合銀粉末的導電性漿料，藉由網版印刷法塗佈此導電性聚料後， 於燒結爐中高溫燒結而成。 月ϋ述導電性漿料通常包括銀粉末、含船玻璃料(細响、有機 3 201044620 溶劑。使用含鉛玻璃料之目的是用來在高溫燒結時蝕穿抗反射層， 使得熔融的銀可以通過抗反射層和石夕晶片表面接觸，於降溫之後形 成導電連結’通常钮穿抗反射層的溫度較高，約為9〇〇°c。在高溫 燒結金屬電極之後，太陽能電池製作及完成，之後，依據不同需求， 可以將太陽能電池加工成為太陽能電池模組。然而，完成的太陽能 電池或模組，經過長期存放後，其金屬電極可能會發生變色瑕疵， 影響電池外觀，造成使用者退貨。 Q 由此可知，業界目前需要一種可以修復這種電極變色瑕疵的方 法，其需具備有低成本、高產出力、無污染，而且不會影響到太陽 能電池或模組的電性效能。 【發明内容】 ，有鑑於此，本發明係提供一種修復太陽能基板電極變色瑕庇的方 法，解決上述先前技藝的問題。 /據本㈣之健實_，本㈣提供-讎復太雜基板電極 變色瑕疲的方法’包含：提供__太陽能基板，其巾在該太陽能基板 的第表面上⑨有至少—表面電極，該表面電極包含—第一金屬氧 化物，且該第-金屬氧化物造成該_變色瑕疲；以及進行一低溫 口火製&，將該表面電軸的該第—金屬氧化物轉縣—第二金屬 氧化物，藉以修復該電極變色瑕疵。 I月之特徵在於利用進行高溫燒結的加熱爐管來進行一低溫 程’藉以修復表面電極原本的顏色。此外，本發明不需使用 予樂劑便稽奴極的顏色，兼具了贱魏汗染和節省成本的 201044620 優點。 為了使貴審查委員能更進一步了解本發明之特徵及技術内 容，請參閱以下有關本發明之詳細說明與附圖。然而所附圖式僅供 參考與輔助說明用，並非用來對本發明加以限制者。 【實施方式】 第1圖是根據本發明之較佳實施例所繪示的是晶矽型太陽能電 0 池之部分結構立體圖。如第1圖所示，一太陽能電池10，包含一太 陽能基板12，經過摻雜與擴散製程之後，於太陽能基板12中形成 Ρ η、纟„構14，太陽能電池1〇另包含有一抗反射膜π設於太陽能 基板12之第一表面18上、一表面電極2〇設於抗反射膜16上以及 者面電極22設於相對於太陽能電池10的第一表面18之一第二表 面24上。通常，表面電極2〇所在的第一表面18是太陽能電池1〇 的受光面，而第二表面24是太陽能電池10的背光面。 一般來說，太陽能基板12可以採用單結晶或多結晶的石夕基板， 了中，抗反射膜16通常可以是由氮化矽所構成，但不限於此。表面 電極20包含由銀、銅、紹、錫、銦或其它的導電材料。背面電極 22較佳係由銀及銘所構成。表面電極20和背面電極22可以利用濺 錢法、真空沉積法、網版印刷法等方式形成。於本實施例中，表面 電極2〇主要是採用混合銀粉末的導電性聚料(銀聚），於燒結爐中， 在_°C的相對高溫下燒結而成。 為了在燒結表面電極2〇使得銀漿可以穿透抗反射膜16和p-n結 構14電連、结’通常會在銀漿中加入含錯玻璃料，其中船玻璃料包含 201044620 η 了氧化錯(PbO) ’即使在太陽能電池10完成之後，表面電極20中依 然含有氧化鉛。但是，發明人發現，太陽能電池10經過長期存放後， 存在於表面電極20中的氧化鉛，會氧化成高價鉛金屬氧化物，例 如：Pb02、Pb3〇4、Pb12〇19、Pb12017和 PbxOy，其中 x>〇，2， 上文所述的高價鉛金屬氧化物係指包含四價鉛的金屬氧化物。由於 表面電極20中的氧化鉛的顏色為黃色’經由氧化之後所形成的高價 鉛金屬氧化物包含有紅色和黑色，所以，顏色較深的高價鉛金屬氧 ❹化物會造成表面電極20產生電極變色瑕庇，例如，造成表面電極 20的顏色變深’影響到太陽能電池的外觀。 因此’發明人經過長期研究，發現了 一種修復太陽能基板電極變 色瑕疵的方法，請參閱第2圖，第2圖繪示的是修復太陽能基板電 極變色之製程示意圖，為求圖示簡單明瞭，第2圖中的太陽能電池 10僅標示表面電極20。首先，提供一加熱爐管5〇，包含一加熱區 52和一輸送帶54。接著，將表面電極20已產生電極變色瑕疵的太 q 陽能電池10放入輸送帶54，並送入加熱區52進行一低溫回火製 程。第2圖中，表面電極20上的點狀表示電極的變色瑕疲。根據本 發明之一較佳實施例，所使用之加熱爐管5〇可以為，例如 Centrotherm photovotaics所生產之設備，型號可以為 DO-FF-8.6_0G ’加熱爐管5G的加熱區52中可依序分為第丨區至 第6區，其中第1區至第6區可個別設定加熱溫度，太陽能電池⑺ 將由輸送帶54傳送，依序經過第！區至第6區加熱回火。根據本發 明之較佳實施例，修復變色瑕疵的條件如下：輸送帶54速度為的⑽ mm/min，加熱區52由第！區至第6區的加熱溫度分別設定為· 6 201044620 °C、400°c、400°c、45〇t、580ΐ、58(TC。需注意的是：上述第 1 區至第6區之加熱溫度係為加熱爐管上内建的溫度計所讀取之溫度 值’為表面電極的周圍溫度(ambient temperature)，並非表面電極的 表面溫度。因此’對於不同的加熱爐管’即使最終會使表面電極的 表面達到相同溫度’但依據其峽的溫度計和太陽能電池的相對位 置的不同，在加舰的溫度設定，會有不_設定值。依據發明人 量測，事實上，表面電極的表面溫度係高於6〇5〇c。除此之外，表 〇 ©t極20的變色瑕疲，主要是在第5區和第6區加熱時修復。第ι 區至第4區的加熱可以選擇性的進行。 根據發明之另-較佳實施例，所使用之加熱爐管5〇同樣為 Centrothermphotovotaics 所生產之設備，型號為 D〇 FF 8 6〇〇 3〇〇， 輸送帶54速度為7500mm/min，加熱區％由第i區至第6區的加 熱溫度分別設定為40(TC、4(Krc、奶此、45叱、6⑻。c、6〇(rc。 士同如述此處所提供的加熱溫度係亦為加熱爐管上内建的溫度計 ^所讀取之溫度值’為表面電極的周圍溫度(ambienttempe論e)，並 非表面電極的表面溫度。依據發明人量測，表面電極的表面溫度高 於 605°C。 I過低恤回火製程後，高價錯金屬氧化物會因為在日蚊以上的 溫度加熱，而還原為氧化錯，使得表面電極2〇㈣極變色瑕庇被快 速修復。如第2圖所示，離開加熱區52後的太陽能電池1〇，其表 =電極20上的變色瑕_ 2圖中以點狀表示)消失。前述的加熱爐 έΐΓ，原本之用途係為燒結爐，用於表面修2G形成時的高溫燒 4程’因此，本個的低溫回火修復電極變色㈣程和高溫燒結 201044620 電極的製程，可以使用相同的加熱爐管，不需另外添構硬體。 當然，本發明修復太陽能基板電極變色瑕庇的方法，不只限於使 用前述的爐管法，亦可以使用其它的加熱方式，例如，紅外線、、雷 射加熱方式或其它低溫回火製程，將太陽能電池的表面電極之表面 溫度加熱至6〇5。(：至6就之間，並且在表面溫度為赋至_ 之間時，持續定溫加熱2秒至3秒，較佳者為2秒至2 9秒才有 修復電極變色喊的效果。值得注意的是：若加熱的溫度太低，或 〇時間過短’會使得表面電極之表面溫度太低，造成變色瑕絲法修 復，若加熱的溫度的溫度太高，或是加熱時間過長，則會使得表面 電極之表面溫度太高，因而造成表面電極剝落，或者影響到電池電 性效能。因此’加熱的溫度和時間是電極變色瑕邮復的關鍵。 本發明利用低溫回火的方式將太陽能基板上的表面電極之中的 馬價齡屬氧化物還原成氧化姑，使得原本由高價錯金屬氧化物所 ^的變色瑕碰復，此方式不需使用化學_即可除去高價船金 Q 屬氧化物，可避免環境汙染問題。 以上所述僅為本發明之較佳實施例，凡依本發明申請專利範圍所 做之均等變化與修飾，皆應屬本發明之涵蓋範圍。 【圖式簡單說明】 2圖是根據本發明之触魏觸_的是㈣型域能電池之 立體圖。 第2圖繪示的是修復太陽能基板電極變色之製程示音圖。 201044620 Ο ίο 14 18 22 50 54 【主要元件符號說明】 太陽能電池 12 太陽能基板 ρ-η結構 16 抗反射膜 第一表面 20 表面電極 背面電極 24 第二表面 加熱爐管 52 加熱區 輸送帶201044620 VI. Description of the Invention: [Technical Field] The present invention relates to a method for repairing a color-changing plague of a solar substrate electrode, and more particularly to a method for repairing the discoloration of a solar substrate electrode by using a chemical-free agent. [Prior Art] 〇 At present, the types of solar cells can be mainly divided into two categories: crystalline germanium and amorphous germanium. In general, in the material of crystalline germanium, germanium atoms have a high degree of periodic arrangement. Therefore, the crystalline germanium solar cell has the highest photoelectric conversion efficiency and good stability. For an amorphous germanium solar cell, since it is usually formed by a plasma chemical vapor deposition method, it is formed into a thin film of amorphous germanium on a substrate, so that it is produced in a manner similar to that of a single crystal germanium and a hawstone. The solar cell is simple and the production speed is also the fastest, but the conversion efficiency of the amorphous solar cell is lower than that of the crystal solar cell. Therefore, the most common application on the market today is based on crystalline germanium solar cells. In general, the monomer (four) system is usually made up of (4) for the production of Shi Xijing tablets, as the substrate of the solar energy pool. Then, the crystal is etched to diffuse a trace amount of boron, a dopant or the like to form a p_n structure on the wafer. And an anti-reflection layer is formed on the surface of the stone wafer, and then a metal electrode is formed on the front and back surfaces of the stone wafer. The anti-reflection layer is generally formed by a deposition process, and the metal electrode is a conductive paste using a mixed silver powder. After the conductive polymer is coated by a screen printing method, it is placed in a sintering furnace. Sintered at high temperature. The conductive paste usually includes silver powder, ship glass frit (fine ring, organic 3 201044620 solvent. The purpose of using leaded glass frit is to etch through the anti-reflective layer during high temperature sintering, so that molten silver can Through the surface contact between the anti-reflective layer and the stone-etched wafer, a conductive connection is formed after the temperature is lowered. Generally, the temperature of the button-through anti-reflection layer is relatively high, about 9 〇〇 ° C. After sintering the metal electrode at a high temperature, the solar cell is fabricated and completed. After that, according to different needs, the solar cell can be processed into a solar cell module. However, after the long-term storage of the completed solar cell or module, the metal electrode may undergo discoloration, which affects the appearance of the battery and causes the user to return the product. Q It can be seen that the industry currently needs a method for repairing such an electrode discoloration enthalpy, which needs to have low cost, high productivity, no pollution, and does not affect the electrical performance of the solar cell or module. In view of the above, the present invention provides a method for repairing the discoloration of the solar substrate electrode and solving the problem. The problem of the above prior art. / According to the health of the present (4), this (4) provides a method for discoloration and fatigue of the electrode of the ruthenium substrate. The method includes: providing a solar substrate with a towel on the surface of the solar substrate. There is at least a surface electrode comprising - a first metal oxide, and the first metal oxide causes the _ discoloration fatigue; and performing a cryogenic firing method, the first metal of the surface electrical axis The oxide is converted to a second metal oxide to repair the electrode discoloration 瑕疵. I month is characterized by using a heating furnace tube for performing high temperature sintering to perform a low temperature process to repair the original color of the surface electrode. Further, the present invention does not It is necessary to use the color of the predator, and it has the advantages of 201044620, which is the result of Wei Wei dyeing and cost saving. In order to enable the reviewing committee to further understand the characteristics and technical contents of the present invention, please refer to the following related to the present invention. The drawings and the accompanying drawings are for the purpose of illustration and description, and are not intended to limit the invention. A preferred embodiment of the present invention is a partial perspective view of a crystalline solar cell. As shown in FIG. 1, a solar cell 10 includes a solar substrate 12, after being doped and diffused, on a solar substrate. In FIG. 12, Ρ, 构, 14 are formed, and the solar cell 1 further includes an anti-reflection film π disposed on the first surface 18 of the solar substrate 12, a surface electrode 2 disposed on the anti-reflection film 16, and a surface electrode 22 is disposed on a second surface 24 of the first surface 18 of the solar cell 10. Typically, the first surface 18 on which the surface electrode 2 is located is the light receiving surface of the solar cell 1 , and the second surface 24 is a solar cell. The backlight surface of 10. In general, the solar substrate 12 may be a single crystal or a polycrystalline lining substrate. The antireflection film 16 may be generally composed of tantalum nitride, but is not limited thereto. The surface electrode 20 contains a conductive material of silver, copper, bismuth, tin, indium or the like. The back electrode 22 is preferably made of silver and metal. The surface electrode 20 and the back surface electrode 22 can be formed by a sputtering method, a vacuum deposition method, a screen printing method, or the like. In the present embodiment, the surface electrode 2 is mainly formed by sintering a conductive polymer (silver polymerization) mixed with silver powder in a sintering furnace at a relatively high temperature of _ °C. In order to sinter the surface electrode 2 so that the silver paste can penetrate the anti-reflection film 16 and the pn structure 14 to electrically connect, the junction will usually be added to the silver paste containing the wrong glass frit, wherein the ship glass frit contains 201044620 η oxidation error (PbO ) Even after the solar cell 10 is completed, the surface electrode 20 still contains lead oxide. However, the inventors have found that after long-term storage of the solar cell 10, the lead oxide present in the surface electrode 20 is oxidized to a high-priced lead metal oxide such as Pb02, Pb3〇4, Pb12〇19, Pb12017 and PbxOy, wherein x> 〇, 2, The high-priced lead metal oxide described above means a metal oxide containing tetravalent lead. Since the color of the lead oxide in the surface electrode 20 is yellow', the high-priced lead metal oxide formed after the oxidation contains red and black, the dark-colored high-priced lead metal oxonide causes the surface electrode 20 to cause electrode discoloration. The shelter, for example, causes the surface electrode 20 to become darker in color, which affects the appearance of the solar cell. Therefore, after long-term research, the inventor discovered a method for repairing the color-changing enamel of the solar substrate electrode. Please refer to FIG. 2, and FIG. 2 is a schematic diagram of the process for repairing the discoloration of the solar substrate electrode, which is simple and clear for the sake of illustration. The solar cell 10 in the figure 2 only indicates the surface electrode 20. First, a heating furnace tube 5 is provided, including a heating zone 52 and a conveyor belt 54. Next, the solar cell 10 having the surface electrode 20 having the electrode discoloration enthalpy is placed in the conveyor belt 54 and fed to the heating zone 52 for a low temperature tempering process. In Fig. 2, the dot on the surface electrode 20 indicates the discoloration of the electrode. According to a preferred embodiment of the present invention, the heating furnace tube 5 used may be, for example, a device manufactured by Centrotherm photovotaics, and may be of the type DO-FF-8.6_0G 'heating furnace tube 5G heating zone 52 The sequence is divided into the third to the sixth zone, in which the heating temperature can be set individually in the first zone to the sixth zone, and the solar cell (7) will be transported by the conveyor belt 54 and sequentially passed through! Zone to Zone 6 is heated and tempered. According to a preferred embodiment of the present invention, the conditions for repairing the discoloration enamel are as follows: the speed of the conveyor belt 54 is (10) mm/min, and the heating zone 52 is by the first! The heating temperatures from the zone to the sixth zone are set to · 6 201044620 ° C, 400 ° c, 400 ° c, 45 〇 t, 580 ΐ, 58 (TC. Note that the heating of the first zone to the sixth zone is mentioned above. The temperature is the temperature value read by the built-in thermometer on the heating tube. 'The ambient temperature of the surface electrode is not the surface temperature of the surface electrode. Therefore, 'for different heating tubes', even the surface will eventually The surface of the electrode reaches the same temperature', but depending on the relative position of the thermometer and the solar cell of the gorge, there is a set value in the temperature setting of the ship. According to the inventor's measurement, in fact, the surface temperature of the surface electrode The system is higher than 6〇5〇c. In addition, the discoloration of the surface 〇©t pole 20 is mainly repaired when heating in the 5th and 6th zones. The heating in the 1st to 4th zones can be selected. According to another preferred embodiment of the invention, the heating furnace tube 5 used is also a device manufactured by Centrothermphotovotaics, model number D〇FF 8 6〇〇3〇〇, conveyor belt 54 speed 7500 mm/ Min, the heating zone % from the ith zone to the sixth zone The heating temperature of the zone is set to 40 (TC, 4 (Krc, milk, 45 叱, 6 (8), c, 6 〇 (rc. The heating temperature system provided here is also built-in on the heating furnace tube). The temperature value read by the thermometer ^ is the ambient temperature of the surface electrode (ambienttempe on e), not the surface temperature of the surface electrode. According to the inventors' measurement, the surface temperature of the surface electrode is higher than 605 ° C. After the fire process, the high-priced metal oxide will be reduced to oxidative error due to heating at a temperature above the Japanese mosquito, so that the surface electrode 2 四 (4) pole discoloration is quickly repaired. As shown in Fig. 2, leaving the heating zone 52 The rear solar cell 1 〇, the surface = the color change 瑕 _ 2 on the electrode 20 is indicated by a dot) disappears. The above-mentioned heating furnace is originally used as a sintering furnace for the high temperature at the time of surface repair 2G formation. Burning 4 steps' Therefore, this low temperature tempering repair electrode discoloration (four) process and high temperature sintering 201044620 electrode process, the same heating furnace tube can be used without additional hardware. Of course, the invention repairs the solar substrate electrode discoloration Method of sheltering It is not limited to the use of the aforementioned tube method, and other heating methods such as infrared, laser heating or other low temperature tempering processes may be used to heat the surface temperature of the surface electrode of the solar cell to 6 〇 5. (: Between 6 and 5%, and when the surface temperature is between _, continuous heating is carried out for 2 seconds to 3 seconds, preferably 2 seconds to 2 seconds to repair the effect of discoloration of the electrode. Yes: If the heating temperature is too low, or the simmering time is too short, the surface temperature of the surface electrode will be too low, causing the discoloration method to repair. If the temperature of the heating temperature is too high, or the heating time is too long, then The surface temperature of the surface electrode is too high, thereby causing the surface electrode to peel off or affecting the battery electrical performance. Therefore, the temperature and time of heating are the key to the electrode discoloration. The invention reduces the equine-aged oxides in the surface electrodes on the solar substrate to the oxidized agglomerates by means of low-temperature tempering, so that the color-changing ruthenium originally occupied by the high-priced erroneous metal oxides is not used. Chemistry _ can remove high-priced ship gold Q oxides to avoid environmental pollution problems. The above are only the preferred embodiments of the present invention, and all changes and modifications made to the scope of the present invention should fall within the scope of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 2 is a perspective view of a (four) type field energy battery according to the present invention. Figure 2 is a schematic diagram showing the process of repairing the discoloration of the solar substrate electrode. 201044620 Ο ίο 14 18 22 50 54 [Description of main components] Solar cell 12 Solar substrate ρ-η structure 16 Anti-reflection film First surface 20 Surface electrode Back electrode 24 Second surface Heating tube 52 Heating zone Conveyor belt