201125133 六、發明說明： 【發明所屬之技術領域】 本發明係在提供一種選擇性發射極太陽能電池的雷射製 程，尤指運用於使用雷射滲雜製程，改善電阻的效應，進而提 升太陽能電池效率。 【先前技術】 按’近年來’工業技術不斷的推陳出新，科技日新月異的 結果為大眾帶來了種種的便利’相對也對整個地球生態及環境 造成了破壞’隨著環保意識的逐漸增長，大眾在享受便利的同 時’也對於工業製造的過程有了更多的期許與規範，而太陽能 的使用則正是符合了對於環保的具體實現，透過太陽能電池使 太陽能轉換為電能儲存及使用。一般網版印刷（Screen Printed)太陽能電池的結構，由於金屬手指電極（Metal Finger Contact)的面積較寬會造成入射光線的遮蔽，產生了 較低的效率，且由於寬的金屬電極^仏丨c〇ntact)，使得電 子與電洞對快速復合，另一方面，底部的發射極金屬電極 (Metal Contact)的下面亦產生了壞死區（Dead Area)，這些 缺點限制了太陽能電池難以提升較好高的效率。因此，無論^ 反射光造成的損失、材料對太陽光的吸引能力不足、載子在尚 未被導出之前就被材料的缺陷捕捉而失效，這些因素都合使 太陽能電池效率的下降。 s 是以’如何針對上述習知太暢能電池於製程中所產生之缺 點進行研發改良，以求增加太陽能電池正面光吸收效率、增加 f面U成以及增加電流收鮮，提高太陽能電池整體的效 ^ ’實為相關業界所需努力研發之目標，本發明人即有鑑於 =，乃思及創作的絲’遂以多年的經驗加以開發設計，經多 方探討並試作樣品試驗，及多次修正改良，乃推出本發明。 201125133 【發明内容】 有鑒於習知太陽能電池製程，於品質及成本上所造成的不 當影響’如何開發改善太陽能電池於製程中的問題及穩定性， 進而提昇整體良率，實為目前業界最為刻不容緩的要事。 本發明係在提供一種選擇性發射極太陽能電池的雷射製 程’其步驟係包括： (1) 使用短波雷射（例如：紫外線（uv)雷射）將氮化石夕抗反 射層（Silicon Nitride Anti-Reflection Coating Layer)做部份切除； (2) 佈植(c〇at)渗雜物(dopant)在石夕晶片上； ® (3)將矽晶片移動至另一雷射源，使用綠光雷射熱溶在矽 晶片上的滲雜物（d〇pant)或已滲入高濃度滲雜物 (dopant)的η型層（n+ layer)，並且亦熱溶在矽晶片 上的金屬電極（metal contact)所需覆蓋的局部區 域，且由於在η型層表面的滲雜物（d〇pant)釋放出滲 ^物(dopant)，雷射會熱溶下面的矽晶片和產生強化 局濃度渗雜的η型層（nH layer); ⑷使用化學方式去除在n型層表面的渗雜物(㈣抓)之 後’利用電鐘法（electricai piating)或無電鍵法 • PlatinS)電鍍金屬電極(metal contact) 在向遭度渗雜的石夕晶片表面上； 藉由上述步驟操作，得改善金屬與矽的接合處，強化抗反 射層晶粒邊界以及抗反射射驗結密度，有效增加光源進入 抗反射膜時吸收，形成良好的短波長吸收效果，且達到減少太 陽能電池表面抗反射層與矽界面的懸浮鍵復合，改善電阻 應’進而提升太陽能電池效率之特性者。 對照先前技術之功效： (一）使用雷射滲雜技術可避免在金屬電極下 區（Dead Area)。 土』农夕匕 201125133 (二） 使用雷射滲雜技術可以選擇欲移除抗反射層 (Anti-ReflectionCoating)的位置，並且可在石夕晶 片上作局部的加熱。 (三） 使用雷射渗雜技術可以熱熔複合渗雜物到已熱溶的 石夕晶片區域’並且產生強化高濃度參雜的η型層 (n++ layer) ° (四） 金屬電極（Metal Contact)可縮小寬度（4〇um width)，增加矽晶片表面上入射光線的面積。 (五） 雷射切割不會損傷石夕基質（silicon matrix)» (六） 雷射滲雜製程可適用於塗佈鋁金屬層（aluminum back surface field; A1 BSF)製程步驟的之前或之 後。 / (七） 雷射滲雜技術亦可使用於二氧化矽抗反射層（Si〇2 Anti-Reflection Coating Layer)、二氧化鈦抗反 射層（Ti02 Anti-Reflection Coating Layer)或氮 化石夕抗反射層（Silicon Nitride Anti-Reflection Coating Layer)。 (八） 發射極的電阻(Rs)是101Μ20Ω，並且高於傳統的網 版印刷(Screen Printed)太陽能電池。 【貫施方式】 為使貴審查委員對本創作之目的、特徵及功效能夠有更 進一步之瞭解與認識，以下茲請配合【圖式簡單說明】列舉實 施例，詳述說明如后： 請先參閱第1圖、第2圖所示，本發明係在提供一種選擇 性發射極太陽能電池的雷射製程，其步驟係包括： (1) 使用短波雷射（例如：紫外線(UV)雷射）將氮化矽抗反 射層（1 1) (SiNx ARC)做部份切除； (2) 佈植（coat)滲雜物(dopant)在矽晶片（1 〇)(卩却^ substrate)上； 201125133 (3 )將石夕晶片（1 〇 ) (p_type substrate)移動至另一雷射源， 使用綠光雷射熱溶在石夕晶片上（1 〇) (p_type substrate) 的滲雜物(dopant)或已滲入高濃度滲雜物(dopant)的 π型層（1 3) (n+ layer)，並且亦熱溶在矽晶片（1 〇) (P-type substrate)上的金屬電極(metal contact)所需 覆蓋的局部區域，且由於在η型層表面的滲雜物 (dopant)釋放出渗雜物（dopant)，雷射會熱溶下面的 石夕晶片（1 0) (P-type substrate)和產生強化高濃度滲雜 的 η 型層（1 4) (n++ layer); (4)使用化學方式去除在η型層表面的滲雜物(dopant)之 ® 後’利用電鍍法（electrical plating)或無電鍍法 (electroless plating)電鍍金屬電極（1 2) (metal contact)在高濃度滲雜(heavily doped)的石夕晶片（1 0) (P-type substrate)表面上； 藉由上述步驟操作，得改善金屬與矽的接合處，強化抗反 射層晶粒邊界以及抗反射層矽氫鍵結密度，有效增加光源進入 抗反射膜時吸收’形成良好的短波長吸收效果，且達到減少太 陽能電池表面抗反射層與梦界面的懸浮鍵復合，改善電阻的效 應，進而提升太陽能電池效率之特性者。 鲁 其中’ 5亥步驟⑴〜(4)可使用於塗佈銘金屬層（aluminum back surface field; A1 BSF)製程步驟的之前或之後。 又其中’該步驟(1)亦可使用於二氧化矽抗反射層（Si〇2 Anti-Reflection Coating Layer)或二氧化鈦抗反射層（Ti〇2 Anti-Refleetion Coating Layer) ° 再者，該步驟(1)亦可使用短脈衝雷射(例如：披秒铷雅克 雷射〈Picosecond Laser〉或飛秒雷射〈Femtosecond Laser〉)將 抗反射層（1 1) (SiNx ARC)做部份切除。 最後，該步驟(4)，電鍍金屬電極（1 2)可使用電鍍法 (electrical plating)或無電鑛法(electroless plating)。 201125133 唯以上所述者，僅為本創作之一較佳實施例而已，當不能 以之限定本發明實施之範圍；即大凡依本發明申請專利範圍所 作之均等變化與修飾，皆應仍屬本發明專利涵蓋之範圍内。201125133 VI. Description of the Invention: [Technical Field] The present invention provides a laser process for a selective emitter solar cell, particularly for use in a laser infiltration process to improve the effect of resistance, thereby improving solar cells. effectiveness. [Prior Art] According to the 'in recent years' industrial technology, the results of the ever-changing technology have brought various conveniences to the public 'relatively, it has also caused damage to the entire earth's ecology and environment'. With the increasing awareness of environmental protection, the public is While enjoying the convenience, there are more expectations and specifications for the process of industrial manufacturing, and the use of solar energy is in line with the specific realization of environmental protection, through solar cells to convert solar energy into electrical energy storage and use. The structure of a general screen printed solar cell has a lower efficiency due to the wider area of the metal finger electrode, resulting in lower efficiency, and due to the wide metal electrode. 〇ntact), which makes the electron and hole pairs quickly recombine. On the other hand, the bottom of the emitter metal electrode (Metal Contact) also produces a dead zone (Dead Area), these shortcomings limit the solar cell is difficult to upgrade better s efficiency. Therefore, no matter the loss caused by the reflected light, the insufficient attraction of the material to the sunlight, and the failure of the carrier to be captured by the defect of the material before it is exported, these factors all contribute to the decrease in the efficiency of the solar cell. s is based on 'how to develop and improve the shortcomings of the above-mentioned conventionally unsatisfactory battery in the process, in order to increase the solar cell front light absorption efficiency, increase the f-plane U and increase the current collection, and improve the overall solar cell. The effect is 'actually the goal of the relevant industry to develop hard, the inventor is in view of =, Naisi and the creation of silk '遂 with years of experience to develop and design, through multiple discussions and trial sample test, and multiple corrections Improvements have been made in the present invention. 201125133 [Invention] In view of the undue influence of the solar cell process on quality and cost, 'how to develop and improve the problem and stability of solar cell in the process, and thus improve the overall yield, it is the most urgent in the industry. The important thing. The present invention is directed to a laser process for providing a selective emitter solar cell. The steps of the present invention include: (1) using a short-wave laser (for example, ultraviolet (uv) laser) to form a nitride nitride anti-reflection layer (Silicon Nitride Anti) -Reflection Coating Layer); (2) implant (c〇at) dopant on the stone wafer; ® (3) move the wafer to another laser source, using green light A metal electrode (metal) that is hot-dissolved on a germanium wafer or a n-type layer that has penetrated into a high-concentration dopant and is also hot-dissolved on a germanium wafer. Contact) the local area to be covered, and because the dopants on the surface of the n-type layer release the dopant, the laser will thermally dissolve the underlying germanium wafer and produce enhanced localized concentration. N-type layer (nH layer); (4) chemically remove the dopant on the surface of the n-type layer ((4) scratch) 'electrical piating (electricai piating or no electric key method • PlatinS) plating metal electrode (metal contact ) on the surface of the stone etched wafer that has been soaked; The joint between the metal and the crucible strengthens the grain boundary of the anti-reflection layer and the density of the anti-reflection shot, effectively increases the absorption of the light source into the anti-reflection film, forms a good short-wavelength absorption effect, and reduces the anti-reflection layer on the surface of the solar cell. The hovering bond of the 矽 interface is compounded to improve the resistance of the solar cell. In contrast to the efficacy of the prior art: (a) the use of laser doping techniques can be avoided in the metal region (Dead Area).土』农夕匕 201125133 (B) The use of laser doping technology can choose the location to remove the anti-reflection layer (Anti-Reflection Coating), and can be locally heated on the Shi Xi wafer. (3) Using the laser doping technique, the composite dopant can be hot-melted into the hot-dissolved Shihua wafer region' and the n-type layer (n++ layer) which enhances the high-concentration doping is generated. (4) Metal electrode (Metal Contact ) The width (4〇um width) can be reduced to increase the area of incident light on the surface of the germanium wafer. (5) Laser cutting does not damage the silicon matrix» (6) The laser infiltration process can be applied before or after the aluminum back surface field (A1 BSF) process. / (7) Laser doping technology can also be used in the antimony anti-reflection layer (Si〇2 Anti-Reflection Coating Layer), the TiO2 anti-Reflection Coating Layer or the nitriding anti-reflection layer ( Silicon Nitride Anti-Reflection Coating Layer). (8) The emitter resistance (Rs) is 101 Μ 20 Ω and is higher than conventional Screen Printed solar cells. [Comprehensive application method] In order to enable your review committee to have a better understanding and understanding of the purpose, characteristics and efficacy of this creation, please refer to the following [Simplified description of the drawings] to illustrate the examples, as detailed below: Please refer to 1 and 2, the present invention provides a laser process for a selective emitter solar cell, the steps of which include: (1) using a short-wave laser (for example, ultraviolet (UV) laser) The tantalum nitride antireflection layer (1 1) (SiNx ARC) is partially cut off; (2) the coating dopant is on the tantalum wafer (1 〇) (卩 ^ ^ substrate); 201125133 ( 3) Moving the p_type substrate to another laser source, using a green laser to thermally dissolve the dopant on the p_type substrate (p_type substrate) or The π-type layer (1 3) (n+ layer) which has penetrated into the high-concentration dopant and is also required to be thermally dissolved in the metal contact on the P-type substrate. Covering the local area, and because the dopant on the surface of the n-type layer releases the dopant, the laser will Dissolving the following P-type substrate and the n-type layer (1 4) (n++ layer) which produces enhanced high-concentration doping; (4) chemically removing the surface of the n-type layer After the doping of the dopant, 'metal contact or electroless plating is used to plate the metal electrode (1 2) (metal contact) in a highly doped (heavily doped) stone wafer (1) 0) (P-type substrate) on the surface; by the above steps, the joint between the metal and the crucible is improved, the grain boundary of the anti-reflection layer and the hydrogen bonding density of the anti-reflection layer are strengthened, and the light source is effectively increased into the anti-reflection film. At the time of absorption, a good short-wavelength absorption effect is formed, and the suspension key combination of the anti-reflection layer on the surface of the solar cell and the dream interface is reduced, the effect of the electric resistance is improved, and the efficiency of the solar cell is improved. Lu's 5th steps (1) to (4) can be used before or after the process of coating the aluminum back surface field (A1 BSF). In addition, the step (1) can also be used for a Si 2 anti-Reflection Coating Layer or a Ti 2 Anti-Refleetion Coating Layer. 1) The anti-reflective layer (1 1) (SiNx ARC) can also be partially cut off using a short-pulse laser (for example, Picosecond Laser or Femtosecond Laser). Finally, in the step (4), the electroplated metal electrode (12) may be electrically plated or electrolessly plated. 201125133 The above is only one preferred embodiment of the present invention, and the scope of the present invention cannot be limited thereto; that is, the equal variation and modification of the scope of the patent application of the present invention should still belong to the present invention. Within the scope of the invention patent.
[si 7 201125133 【圖式簡單說明】 第1圖係本發明之流程步驟圖。 第2圖係本發明之流程示意圖。 【主要元件符號說明】 (10)矽晶片 (1 1)氮化矽抗反射層 (1 2)金屬電極 (13)已滲入高濃度渗雜物的η型層 (1 4)強化高濃度滲雜的η型層[si 7 201125133 [Simplified Schematic] FIG. 1 is a flow chart of the present invention. Figure 2 is a schematic flow diagram of the present invention. [Description of main component symbols] (10) 矽 wafer (1 1) yttrium nitride anti-reflective layer (1 2) metal electrode (13) has penetrated into the high-concentration η-type layer (14) to enhance high-concentration osmosis N-type layer