201211214 六、發明說明： 【發明所屬之技術領域】 本發明是關於一種矽基材之钮刻液及蝕刻方法，尤指 一種適用於生產太陽能電池之矽晶片制絨製程中的蝕刻 液組成及其蝕刻方法。 【先前技術】 採用酸性或鹼性蝕刻液來對矽晶片進行侵蝕，以在發 晶片表面上構成特定區域的結構化表面，這在半導艘製程 中是很常見的濕蝕刻（WetEtching)製程。然而，為了不 同目的所進行的各種蚀刻製程之間，卻也有相當差異。例 如，對於在矽晶片上構成元件間絕緣溝渠的淺溝渠隔離 (ShallowTrench Isolation ;簡稱 STI)製程，和用以製作 太陽能電池時在矽晶片表面上構成金字塔群結構的表面 制絨（SurfaceTexturization)製程，其兩者所使用的蝕刻 液配方以及蝕刻製程條件便有極大差異。 目前，在製作太陽能電池時所使用的制絨製程，多半 是使用包含了氫氧化卸（KOH)或氫氧化納（NaOH)所 構成之鹼性溶液的濕蝕刻製程。為了協助在矽晶片表面有 效率地形成金字塔群結構的目的，在這驗性溶液中還添加 了一定淚度但是卻不參與蚀刻反應的界面活性劑，例如異 丙醇（IPA)等。然而，這種習知的作法仍有其缺失。由 於目前的濕蝕刻製程大多是在75eC〜85它之間的溫度下 進行，此一製程溫度已接近或高於異丙醇的沸點，所以， 在蝕刻過程中界面活性劑不僅將會因揮發而浪費，且操作 201211214 人員還得定期性地去添加界面活性劑而造成麻煩。 曾有業界嘗試針對製作太陽能電池時的矽晶片制絨 製程來開發出新的蝕刻液配方與蚀刻製程，並嘗試以其他 成分來取代異丙醇作為界面活性劑，以試圖改善制絨效 果。然而，這些嘗試有些雖可得到較佳制絨效果但卻仍無 法避免界面活性劑揮發浪費的困擾、另一些則是因未能開 發出最佳的蝕刻液配方或是製程條件而無法獲得最佳的 制絨效果，而都仍有進一步改善的空間。 台灣發明專利公開號TW 200835778案曾揭露一種 用於矽表面及矽層之含粒子蝕刻糊料。然而，此習知技術 之姓刻糊料並不適於作為本發明所述之矽晶片制絨製程 的蝕刻液，因為其所揭露之黃原膠、纖維素等添加物主要 是用來當作蝕刻糊料之「增稠劑」而非本發明所述之界面 活性劑》所以，TW200835778案之黃原膠、纖維素等添 加物的濃度需高達0.5%~25%之多才能提供「增稠」效果， 倘若將其使用在矽晶片制絨製程的話反而會大幅降低银 刻率且將降低在矽晶片表面上的制絨效果。此外，過高濃 度的界面活性劑因為會降低*蚀刻量，所以需要以更高濃度 的驗性溶液來提高蝕刻量，如此會增加生產成本;另一缺 點是過多的界面活性劑與鹼性溶液會增加蝕刻液的黏度 及比重，會影響蝕刻液濃度均勻性，以及對於濕蝕刻設備 增加馬達的負擔。 台灣發明專利公開號TW 200913045案曾揭露一種 處理矽晶圓之方法與處理液體，其係在鹼性處理液體中加 入含量介於1%~15%之間的添加劑例如多醣類等來作為 201211214 蝕刻抑制劑。然而，此習知技術所揭露之添加劑的含量 1°/〇~15%仍屬過高，同樣具有會大幅降低钮刻率以及降低 制絨效果的缺點。此外，過高濃度的界面活性劑因為會降 低蚀刻量，所以需要以更高濃度的鹼性溶液來提高蝕刻 量，如此會增加生產成本;另一缺點是過多的界面活性劑 與驗性溶液會增加蝕刻液的黏度及比重，會影響蝕刻液濃 度均勻性，以及對於濕蝕刻設備增加馬達的負擔。 台灣發明專利公開號TW 200816507案曾揭露一種 製造太陽能電池之矽晶圓刻紋方法，其係在鹼性處理液體 中加入含量低於0.01%的界面活性劑。然而，此習知技術 不僅並未具體揭露其界面活性劑的組成配方，其僅提及界 面活性劑可以是洗碗精或清潔劑，而這些市售洗碗精或清 潔劑中或許含有不利於矽晶圓制絨或其他後續製程的不 知名雜質成分，完全不能符合業界對於钮刻液成分標準化 與精煉化的要求。更何況，此習知技術僅討論到界面活性 劑對於制絨後之梦晶圓表面反射率的影響，但對於更重要 的「金字塔群覆蓋率」、「蝕刻量」以及「金字塔群均勻性」 則完全未討論，所以此習知技術在實際應用上是否真能生 產出勘用的成品仍有疑慮。此外，此習知技術所揭露的製 程反應溫度達到98°C (至少90°c以上），不僅與業界慣用 的75°C〜85t製程溫度範圍不同，甚至已接近水的沸點， 顯然不符合現實太陽能電池生產業界的實際需求。此外， 目前太陽能制絨設備多半使用塑材（如：P P、P VD F、 P T F E…等）或金屈包覆塑材槽體與管件，主要避免金 屬離子析出而降低晶片轉換效率。製程溫度越高對於银刻 201211214 機台所選用元件、材料的要求越高，而且高溫所產生的溶 液大量蒸發對於钱刻液的濃度維護不易;另外，座務端要 供應較多的能源來維持1¾溫’對於要處理較多的蒸氣也是 一大負擔。 【發明内容】 本發明之第一目的是在於提供一種矽基材之蝕刻 液’其配方中包含了沸點高於敍刻製程溫度的多醣體物質 • 來作為界面活性劑，而可改善界面活性劑在蝕刻製程中因 揮發而浪費的缺點。此外，本發明之界面活性劑是易於取 得的。 本發明之第一目的是在於提供一種發基材之蚀刻液 及蝕刻方法，藉由較佳化之蚀刻液配方以及製程條件，不 僅可獲得更良好的制絨效果，更可直接導入業界現有太陽 能電池生產線的實際需求。 為達上述之目的，本發明之矽基材之钮刻方法，係在 籲 一製程溫度下將該珍基材浸入一蚀刻液中停留一製程時 間後取出’於該蝕刻液中包括了將一水溶性鹼性物質以及 一界面活性劑溶解於水中所構成之鹼性溶液。其中，該界 面活性劑係包括有至少一種多醣體物質，且該界面活性劑 於該蚀刻液中的重量百分比濃度係小於2000ppm。 為達上述之目的，本發明之矽基材之蝕刻液，係包括 有：作為該蝕刻液之主要溶劑的水、一水溶性驗性物質、 以及一界面活性劑。該水溶性鹼性物質係溶解於水中成為 可對該矽基材進行蝕刻的一鹼性溶液。該界面活性劑係添 201211214 加於該鹼性溶液中，用以協助該鹼性溶液對矽基材的蝕刻 效果。其中，該界面活性劑係包括有至少一種多醣體 (Polysaccharide)物質，且該界面活性劑於該蝕刻液中的 重量百分比浪度係小於2000ppm。 於一較佳實施例中，該多醣體物質係一混合物，其包 括有： 一第一成分，其係由下列物質中選擇至少其中之一： 甲基織維素(MC)、黃原膠(X.G)、疏水性改質羥乙基纖維 素、羥丁基曱基纖維素、曱基羥乙基纖維素、丙酸纖維素、 乙酸纖維素、羥丙基曱基織維素、羥丙基纖維素、曱殼素、 鹿角菜膠、刺槐豆膠、果膠、塔拉膠、阿拉伯膠、結蘭膠、 膳食纖維；其中，該第一成分於該蚀刻液中的重量百分比 濃度係小於lOOOppm ;以及 一第二成分，其係由下列物質中選擇至少其中之一： C18〜22羥烧基羥丙基瓜兒膠、羥丙基瓜兒膠、羧甲基瓜 兒膠、羧甲基羥丙基瓜兒膠、水解瓜兒膠、羧甲基纖維素 鈉(CMC-Na)、褐藻醣膠、香菇多醣、蟲草多醣、海藻酸 鈉；其中’該第二成分於該蝕刻液中的重量百分比濃度係 小於 lOOOppm。 於一較佳實施例中，該第一成分包括了甲基纖維素 (MC) ’且該曱基纖維素(MC)之重量百分比濃度為介於 O.lppm〜5ppm;並且，該第二成分包括了 C18〜22羥烷基 羥丙基瓜兒膠以及羧甲基纖維素鈉(CMC-Na)，且該 C18-22羥烷基羥丙基瓜兒膠之重量百分比濃度為介於 lppm~ lOOppm，且該羧甲基纖維素鈉(CMC-Na)之重量百 201211214 分比濃度為介於20ppm〜300ppm。 於另一較佳實施例中，該第一成分包括了黃原膠 (X.G)，且該黃原膠(X.G)之重量百分比濃度為介於 50ppm〜lOOppm ;並且，該第二成分包括了 C18〜22經烧 基羥丙基瓜兒膠及羧甲基織維素鈉(CMC-Na)，且該 C18〜22羥烷基羥丙基瓜兒膠之重量百分比濃度為介於 lppm〜lOOppm，且該羧甲基纖維素鈉(CMC-Na)之重量百 分比浪度為介於20ppm〜300ppm。 【實施方式】 為了能更清楚地描述本發明所提出之矽基材之蚀刻 液及蚀刻方法，以下將配合圖式詳細說明之。 本發明之梦基材之蝕刻液及姓刻方法，主要是針對製 作太陽能電池時在矽晶片表面上構成金字塔群結構的制 絨製程。因此，以下之說明將僅針對制絨製程之蚀刻液配 方以及製程條件進行說明。至於，對於製作太陽能電池的 • 其他製程說明，由於係屬習知技術，於本文中將不予贅 述’讀者可另參考台灣發明專利公開號TW 201027617 A1案内容。然而，該案並未揭露、教導或暗示本發明的 技術特徵，也無法達成與本發明相同或等效的功效。 本發明之矽基材之蝕刻方法，主要是使用鹼性溶液的 濕姓刻製程，在一製程溫度下將一矽基材浸入一蝕刻液中 停留一製程時間，使矽基材暴露於银刻液中的表面被適量 侵蚀後再取出，藉此可在該矽基材的單一表面或是上下兩 表面上形成結構化表面。於本發明中，該矽基材是一單晶 201211214 或是多晶的矽晶片，而所述的結構化表面係指在矽基材至 少一表面上所形成之眾多類似金字塔狀凸起的結構，其每 一個金字塔的高度與寬度一般是介於1 Am〜10#m之間為 佳。此種在矽基材表面上構成金字塔群凸起結構的制絨製 程’可令該矽基材之表面對入射光的反射率大幅降低，因 此被廣泛使用在製作太陽能電池的矽晶片製程上，以提高 太陽能晶片吸收光能以及光電轉換的效率。 於本發明之一較佳實施例中，該蝕刻液係以水（例 如，去離子水DI Water)為主要溶劑，其佔了蝕刻液絕大 部分的重量百分比’並在水中適量添加了一水溶性鹼性物 質、一界面活性劑、以及一發氧化合物（例如：Si〇2或 Xi〇，其中X = KorNa)，而構成本發明之触刻液。基本 上’本發明之钮刻液除了前述物質外，可不再添加其他物 質，例如增稍劑、低熔點極細有機粒子等，於本發明中都 可以不必添加，即能達到本發明宣稱的效果。該水溶性鹼 性物質溶解於水中成為可對該矽基材進行蝕刻的一驗性 溶液，而該界面活性劑添加於該驗性溶液中則可協助該驗 性溶液對矽基材的特定蝕刻效果進而獲得較佳效果的金 字塔群結構。至於，所添加的適量發氧化合物，則可用來 提高金字塔群結構於矽基材表面上的覆蓋率。 其中，該水溶性驗性物質係包括至少下列其中之一： 氫氧化鈉（NaOH)、氫氧化鉀（KOH)。該水溶性鹼性物 質於該蝕刻液中的重量百分比濃度係介於1〇/〇^20%。並 且，該矽氧化合物於該蝕刻液中的重量百分比濃度係介於 0.001%^10%之間，且其濃度係隨著水溶性驗性物質的濃 201211214 度增加而增加為較佳。 一般來說，在前述的水溶性驗性物質滚度範圍下，本 發明之蚀刻方法的製程溫度以介於5〇。〇〜9〇。(：之間、且前 述的製程時間以介於lOmin〜30min之間，為可據以實施 的製程條件。然而，當其製程條件進一步限縮在該水溶性 鹼性物質之濃度為介於、製程溫度介於60〇c〜8〇 °C、且製程時間介於lOmin〜25min之間時，本發明之银 刻方法將可獲得更良好的制賊效果’且此一製程條件範圍 • 也符合目前太陽能電池生產業界廣泛慣用的制絨製程條 件’顯見業界將可很輕易地導入本發明所揭露的钮刻方法 於其現有的製程中》 本發明之蚀刻液的技術特徵，主要在其所添加之界面 活性劑的成分、以及蚀刻液中所包含之各成分（包括鹼性 物質、界面活性劑、珍氧化合物）的濃度範圍與含量比例。 於本發明中，該界面活性劑係包括有至少一種多醣體 (Polysaccharide)物質，且該界面活性劑於該蝕刻液中的 ® 重量百分比濃度係小於2000ppm。於本實施例中，該多醣 體物質係包括至少下列其中之一：曱基纖維素(Methyl Cellulose ;簡稱 MC)、黃原膠(Xanthan Gum ;簡稱 X.G)、 C18〜22羥烷基羥丙基瓜兒膠(C18-22 hydroxyalkyl hydroxypropyl guar)、經丙基瓜兒膠(hydroxypropyl guar)、 叛甲基瓜兒膠(carboxymethyl guar)、叛曱基經丙基瓜兒膠 (carboxymethyl hydroxypropyl guar)、水解瓜兒膠 (hydrolyzed guar)、羧甲基纖維素鈉(CMC-Na)、疏水性改 質經乙基纖維素（Hydrophobically Modified Hydroxyethyi 201211214201211214 VI. Description of the Invention: [Technical Field] The present invention relates to a button engraving and etching method for a crucible substrate, and more particularly to an etching liquid composition for a crucible wafer forming process suitable for producing a solar cell and Etching method. [Prior Art] Acidic or alkaline etching solutions are used to etch the tantalum wafer to form a structured surface of a specific area on the surface of the wafer, which is a very common Wet Etching process in a semi-conductor process. However, there are considerable differences between the various etching processes performed for different purposes. For example, a shallow trench isolation (STI) process for forming an insulating trench between components on a germanium wafer, and a surface texturization process for forming a pyramid group structure on a germanium wafer surface for fabricating a solar cell, The etchant formulation used in both of them and the etching process conditions are greatly different. At present, the flocking process used in the production of solar cells is mostly a wet etching process using an alkaline solution composed of hydroxide (KOH) or sodium hydroxide (NaOH). In order to assist in the efficient formation of the pyramid group structure on the surface of the tantalum wafer, a surfactant having a certain degree of tear but not participating in the etching reaction, such as isopropanol (IPA), etc., is added to the test solution. However, this conventional practice still has its shortcomings. Since the current wet etching process is mostly carried out at a temperature between 75eC and 85, the temperature of the process is close to or higher than the boiling point of the isopropanol, so the surfactant will not only be volatilized during the etching process. Waste, and operation 201211214 personnel have to periodically add surfactants to cause trouble. There have been attempts in the industry to develop new etching solution formulations and etching processes for the enamel wafer sizing process for making solar cells, and attempted to replace isopropyl alcohol as a surfactant with other ingredients in an attempt to improve the effect of the velvet. However, some of these attempts can achieve better texturing effect, but still can not avoid the waste of surfactant evaporation, and others are unable to obtain the best etchant formulation or process conditions. The effect of the texturing, and there is still room for further improvement. A particle-containing etching paste for a crucible surface and a crucible layer has been disclosed in Taiwan Patent Publication No. TW 200835778. However, the surname of this prior art is not suitable as an etching solution for the wafer-forming process of the present invention, since the disclosed xanthan gum, cellulose and the like are mainly used for etching. The "thickener" of the paste is not the surfactant according to the present invention. Therefore, the concentration of xanthan gum, cellulose and the like in the TW200835778 case needs to be as high as 0.5% to 25% to provide "thickening". The effect, if used in the enamel wafer texturing process, will substantially reduce the silver engraving rate and will reduce the texturing effect on the ruthenium wafer surface. In addition, too high concentration of surfactant will reduce the amount of etching, so it is necessary to increase the etching amount with a higher concentration of the test solution, which will increase the production cost; another disadvantage is excessive surfactant and alkaline solution. It will increase the viscosity and specific gravity of the etching solution, which will affect the uniformity of the etching solution concentration and increase the burden on the motor for the wet etching device. Taiwan Patent Publication No. TW 200913045 discloses a method and a treatment liquid for treating a tantalum wafer, which is added with an additive such as a polysaccharide having a content of between 1% and 15% in an alkaline treatment liquid as 201211214. Etch inhibitor. However, the content of the additive disclosed in the prior art is still too high in the range of 1 ° / 〇 ~ 15%, and also has the disadvantage of greatly reducing the button ratio and reducing the effect of the pile. In addition, too high concentration of surfactants will reduce the amount of etching, so it is necessary to increase the etching amount with a higher concentration of alkaline solution, which will increase the production cost; another disadvantage is that too much surfactant and test solution will Increasing the viscosity and specific gravity of the etching solution affects the uniformity of the etching solution concentration and the burden on the motor for the wet etching apparatus. Taiwan Patent Publication No. TW 200816507 discloses a method of wafer engraving for manufacturing a solar cell by adding a surfactant having a content of less than 0.01% to an alkaline treatment liquid. However, this prior art does not specifically disclose the compositional formula of the surfactant, and it is only mentioned that the surfactant may be a dishwashing detergent or a detergent, and these commercially available dishwashing detergents or detergents may be disadvantageous for The unknown impurity components of enamel wafer or other subsequent processes are completely incompatible with the industry's requirements for standardization and refining of button engraving components. What's more, this prior art only discusses the effect of surfactants on the surface reflectivity of dream wafers after texturing, but for more important "pyramid group coverage", "etching amount" and "pyramid group uniformity" It is not discussed at all, so there is still doubt about whether this conventional technology can actually produce finished products for exploration. In addition, the process reaction temperature disclosed in the prior art reaches 98 ° C (at least 90 ° C or more), which is not only different from the conventional 75 ° C to 85 t process temperature range, and even close to the boiling point of water, which is obviously not in line with reality. The actual demand of the solar cell production industry. In addition, most of the current solar-texturing equipment uses plastic materials (such as P P, P VD F, P T F E, etc.) or gold-coated plastic tanks and tubes, which mainly avoid metal ion precipitation and reduce wafer conversion efficiency. The higher the process temperature, the higher the requirements for the components and materials selected for the silver engraved 201211214 machine, and the large amount of evaporation of the solution generated by the high temperature is not easy to maintain the concentration of the money engraving; in addition, the seat side needs to supply more energy to maintain the 13⁄4 Wen' is also a big burden for dealing with more steam. SUMMARY OF THE INVENTION A first object of the present invention is to provide an etchant for a ruthenium substrate, which comprises a polysaccharide material having a boiling point higher than the temperature of the engraving process, as a surfactant, and can improve the surfactant. A disadvantage of being wasted by volatilization during the etching process. Further, the surfactant of the present invention is easily available. The first object of the present invention is to provide an etchant and an etching method for a hair substrate, which can not only obtain better dyeing effect but also directly introduce existing solar energy in the industry by using the optimized etching solution formula and process conditions. The actual demand for battery production lines. For the purpose of the above, the button engraving method of the crucible substrate of the present invention is performed by immersing the rare substrate in an etching solution at a process temperature for a process time and then taking out the inclusion in the etching solution. A water-soluble alkaline substance and an alkaline solution in which a surfactant is dissolved in water. Wherein, the surfactant comprises at least one polysaccharide material, and the concentration percentage of the surfactant in the etching solution is less than 2000 ppm. In order to achieve the above object, the etching liquid for the base material of the present invention includes water as a main solvent of the etching liquid, a water-soluble test substance, and a surfactant. The water-soluble basic substance is dissolved in water to form an alkaline solution which can etch the ruthenium substrate. The surfactant is added to the alkaline solution to assist the etching effect of the alkaline solution on the ruthenium substrate. Wherein, the surfactant comprises at least one polysaccharide substance, and the surfactant has a weight percentage of less than 2000 ppm in the etching solution. In a preferred embodiment, the polysaccharide material is a mixture comprising: a first component selected from at least one of the following: methyl woven (MC), xanthan gum ( XG), hydrophobically modified hydroxyethyl cellulose, hydroxybutyl fluorenyl cellulose, mercapto hydroxyethyl cellulose, cellulose propionate, cellulose acetate, hydroxypropyl phthalocyanine, hydroxypropyl Cellulose, chitin, carrageenan, locust bean gum, pectin, tara gum, gum arabic, yam gum, dietary fiber; wherein the concentration of the first component in the etching solution is less than 1000 ppm And a second component selected from at least one of the following: C18-22 hydroxypropyl guar gum, hydroxypropyl guar gum, carboxymethyl guar gum, carboxymethyl hydroxy Propyl guar gum, hydrolyzed guar gum, sodium carboxymethyl cellulose (CMC-Na), fucoidan, lentinan, cordyceps polysaccharide, sodium alginate; wherein 'the weight of the second component in the etching solution The percentage concentration is less than 1000 ppm. In a preferred embodiment, the first component comprises methylcellulose (MC)' and the concentration percentage of the mercaptocellulose (MC) is between 0.1 ppm and 5 ppm; and the second component Including C18-22 hydroxyalkyl hydroxypropyl guar gum and sodium carboxymethyl cellulose (CMC-Na), and the concentration percentage of the C18-22 hydroxyalkyl hydroxypropyl guar gum is between 1 ppm~ lOOppm, and the weight ratio of the sodium carboxymethyl cellulose (CMC-Na) is 20122014, and the concentration is between 20 ppm and 300 ppm. In another preferred embodiment, the first component comprises xanthan gum (XG), and the concentration of the xanthan gum (XG) is between 50 ppm and 100 ppm; and the second component comprises C18. ~22 by using hydroxypropyl guar gum and sodium carboxymethyl vesyl (CMC-Na), and the concentration percentage of the C18~22 hydroxyalkyl hydroxypropyl guar gum is between 1 ppm and 100 ppm. And the weight percentage of the sodium carboxymethyl cellulose (CMC-Na) is between 20 ppm and 300 ppm. [Embodiment] In order to more clearly describe the etching liquid and etching method of the tantalum substrate proposed by the present invention, the following will be described in detail with reference to the drawings. The etching liquid and surname method of the dream substrate of the present invention are mainly directed to a flocking process for forming a pyramid group structure on the surface of a tantalum wafer when manufacturing a solar cell. Therefore, the following description will only be described for the etching solution formulation and process conditions of the texturing process. As for the other process descriptions for making solar cells, it is not covered in this article because it is a well-known technology. The reader can refer to the contents of Taiwan Invention Patent Publication No. TW 201027617 A1. However, the present invention does not disclose, teach or suggest the technical features of the present invention, nor can it achieve the same or equivalent effects as the present invention. The etching method of the crucible substrate of the invention mainly uses a wet etching process of an alkaline solution to immerse a crucible substrate in an etching solution for a processing time at a process temperature, thereby exposing the crucible substrate to silver engraving. The surface in the liquid is etched off by an appropriate amount and then removed, whereby a structured surface can be formed on a single surface or both upper and lower surfaces of the tantalum substrate. In the present invention, the germanium substrate is a single crystal 201211214 or a polycrystalline germanium wafer, and the structured surface refers to a plurality of pyramid-like convex structures formed on at least one surface of the germanium substrate. The height and width of each pyramid are generally between 1 Am and 10 #m. Such a texturing process for forming a pyramid group convex structure on the surface of the tantalum substrate can greatly reduce the reflectance of the surface of the tantalum substrate to incident light, and thus is widely used in a tantalum wafer process for fabricating a solar cell. To improve the efficiency of solar chip absorption of light energy and photoelectric conversion. In a preferred embodiment of the present invention, the etching solution is water (for example, DI Water) as a main solvent, which accounts for a majority of the etching solution by weight% and adds a water-soluble amount in water. A basic alkaline substance, a surfactant, and an oxygen generating compound (for example, Si〇2 or Xi〇, wherein X = KorNa) constitute the etchant of the present invention. Basically, the button engraving of the present invention can be dispensed with other substances, such as a thinner, a low-melting-point ultrafine organic particle, etc., in addition to the above-mentioned substances, and it is possible to achieve the effects claimed in the present invention without adding it in the present invention. The water-soluble alkaline substance is dissolved in water to become an experimental solution for etching the ruthenium substrate, and the surfactant is added to the test solution to assist the specific etching of the ruthenium substrate by the test solution. The effect further results in a pyramid group structure with better effects. As for the appropriate amount of oxygen generating compound, it can be used to improve the coverage of the pyramid group structure on the surface of the crucible substrate. Wherein, the water-soluble test substance comprises at least one of the following: sodium hydroxide (NaOH), potassium hydroxide (KOH). The water-soluble basic substance has a concentration by weight of 1 〇 / 〇 ^ 20% in the etching solution. Moreover, the concentration percentage of the oxygen-containing compound in the etching solution is between 0.001% and 10%, and the concentration thereof is preferably increased as the concentration of the water-soluble test substance increases by 201211214 degrees. Generally, the process temperature of the etching method of the present invention is between 5 Torr under the aforementioned range of water-soluble test substance rolling. 〇~9〇. (: between, and the aforementioned process time is between 10 min and 30 min, which is a process condition that can be implemented. However, when the process conditions are further limited to the concentration of the water-soluble alkaline substance, When the process temperature is between 60 ° C and 8 ° C and the process time is between 10 min and 25 min, the silver engraving method of the present invention can obtain a better thief effect' and the range of process conditions is also met. At present, the conventional flocking process conditions in the solar cell production industry are obvious. It is obvious that the industry can easily introduce the button engraving method disclosed in the present invention in its existing process. The technical characteristics of the etching liquid of the present invention are mainly added thereto. a concentration range of the surfactant and a concentration range and a content ratio of each component (including a basic substance, a surfactant, and an oxygen compound) contained in the etching solution. In the present invention, the surfactant includes at least A polysaccharide (polysaccharide) substance, and the surfactant is present in the etching solution at a concentration of less than 2000 ppm by weight. In the present embodiment, the polysaccharide material The system comprises at least one of the following: Methyl Cellulose (MC), Xanthan Gum (XG), C18-22 hydroxyalkyl hydroxypropyl guar (C18-22 hydroxyalkyl hydroxypropyl guar) ), hydroxypropyl guar, carboxymethyl guar, carboxymethyl hydroxypropyl guar, hydrolyzed guar, carboxymethyl Cellulose sodium (CMC-Na), hydrophobic modification via ethyl cellulose (Hydrophobically Modified Hydroxyethyi 201211214
Cellulose ;簡稱 HMHEC )、經丁基甲基織維素（Hydroxybutyl methyl cellulose)、甲基經乙基纖維素（Methyl 2-hydroxyethyl cellulose)、 丙酸纖維素（Cellulose propionate )、乙酸纖維素（Cellulose acetate)、經丙基甲基織維素（Hydroxypropyl methyl cellulose;簡稱 HPMC)、經丙基織維素（Hydroxypropylcellulose ;簡稱HPC)、曱 殼素、鹿角菜膠（Garrageenan)、刺槐丑膠（Locust bean gum)、 果膠（Pectin)、塔拉膠（Taragum)、阿拉伯膠（Arabicgum)、 結蘭膝（Gellen gum)、腊食纖維（Fiber)、褐藻酿膠、香益 多聽、蟲草多酿、海藻酸納（Sodium Alginate)、或是由植物 鲁 萃取其他種類之多醣體物質，都可以作為本發明之钮刻液 中的界面活性劑的可實施例，然而其含量與濃度仍是能否 獲得良好制絨效果的關鍵之一。 於本發明中，該蝕刻液所包含的多醣體物質，依其成 分的不同’在蝕刻製程中會具有不同的功能與效果。因 此，本發明依據不同多醣體物質所能提供的不同效果，可 大致上將上述的各種多聽趙物質區分為兩個群組，分別簡 稱為第一成份群以及第二成份群。於一較佳實施例中，本 φ 發明之界面活性劑中的多醣體物質是一混合物，其包含了 自第一成份群中所選出之至少一第一成份、以及自第二成 份群中所選取的至少一第二成份。 所述的第一成分群係包括了下列多醣體物質：甲基織 維素(MC)、黃原膠(χ·〇)、疏水性改質羥乙基纖維素、曱 基羥乙基織維素、丙酸織維素、乙酸織維素、羥丙基甲基 纖維素、羥丙基織維素、甲殼素、鹿角菜膠、刺槐豆膠、 果膠、塔拉膠、阿拉伯膠、結蘭膠、膳食織維。此第一成 12 201211214 份群内之多醣體物質可具有在蝕刻製程中增加100/111晶 相蝕刻選擇比的功效，亦即有助於在矽基材表面形成金字 塔狀之凸起。當蝕刻液中所包含之第一成分群之多醣體物 質的濃度增加時’將能提高金字塔群結構在矽基材表面上 的覆蓋率（也就是覆蓋完整度）但同時卻也會使蚀刻率減 少；相反地，當蝕刻液中所包含此一第一成分群之多醣體 物質的濃度減少時，覆蓋率也會隨之降低；所以，決定一 最佳化的濃度範圍是有必要的。於本發明中，該第一成分 於該蚀刻液中的重量百分比渡度係小於lOOOppm，此為可 實施的濃度範圍，至於較佳範圍則待稍後描述。 所述的該第二成分群則是包括了下列多醣體物質： C18〜22羥烷基羥丙基瓜兒膠、羥丙基瓜兒膠、羧甲基瓜 兒膠、羧曱基羥丙基瓜兒膠、水解瓜兒膠、羧曱基纖維素 鈉、褐藻醣膠、香菇多餹、蟲草多醣、海藻酸納。此第二 成份群内之多醣體物質可具有在蝕刻製程中提高反應氣 泡脫離晶片速率的功效。當蝕刻液中所包含之第二成分群 之多醣體物質的濃度增加時，反應氣泡脫離晶片速率增 加，但是蚀刻量卻減少，且因抑制反應導致覆蓋率降低； 所以，決定一最佳化的濃度範圍是有必要的。於本發明 中，該第二成分於該蝕刻液中的重量百分比濃度係小於 lOOOppm，此為可實施的濃度範圍，至於較佳範圍則待稍 後描述。 具艘實施例一： 在製程溫度介於6(TC〜80°C、且製程時間介於 lOmin〜25min之間的製程條件下時，使用以下所述的蝕刻 201211214 液配方來實施本發明之蝕刻方法將可得到良好的制絨效 果。該蝕刻液之配方包括了：水溶性鹼性物質之濃度為 1%~15%、珍氧化合物濃度為0.001%〜10%、以及界面活 性劑。並且，該界面活性劑更包括了選自第一成分群之甲 基纖維素(MC)其濃度為O.lppm〜200ppm、以及選自第 二成分群之C18〜22經烧基經丙基瓜兒谬其壤度為ippm 〜200ppm與羧曱基纖維素鈉(CMC-Na)其濃度為20ppm 〜lOOOppm ;但是該C18〜22羥烷基羥丙基瓜兒膠與該叛 甲基纖維素鈉（CMC-Na)兩者合計之濃度為小於 lOOOppm。依據實驗證明，在此一蝕刻液配方以及製程條 件下所進行的蝕刻製程，將可獲得在矽基材表面上之金字 塔群結構的覆蓋率達到80%以上、蝕刻量（蝕刻深度）介 於4μπι〜20μιη之間、以里華公司之D8反射儀來測試矽基 材表面反射率的值低於17%、且矽基材表面目視均勻性良 好（也就是金字塔結構之大小及分佈都均勻）的效果。這 樣的制絨效果與品質，已能被現今太陽能電池生產業界的 許多業者所接受而認定屬於良品。 請參閱囷一及囷二’分別為依據本發明之姓刻方法具 體實施例一所完成之發基材1表面金字塔群2結構的放大 側視圏以及上視圖。由圖一及圖二可知，本發明之蚀刻方 法具體實施例一可獲得良好且均勻（包括大小均勻以及分 佈均勻）的金字塔群2覆蓋率，其各別金字塔21結構的 傾斜面與矽基材表面之間的夾角約介於45<•〜之間、且 咼度與寬度絕大多數是介於私m之間，也因為金字 塔群2的大小均勻，所以可以進一步降低整體反射率。 201211214 相對地，請參閱囷三及圖四，分別為依據習用技術蚀 刻方法所完紅魏材表©金字塔群結構的放大側視圖 以及上視®。倘若是使肖傳統異丙醇來作為界面活性劑、 或是採用了不良配方的蝕刻液時，則所得到的蝕刻制絨結 果將會如同圖二及圏四所不般，不僅個別金字塔31、32 的大小差距很大，且在部分區域4甚至可能會發生金字塔 群覆蓋不足的缺點，而導致不良率的提升。 然而’當把界面活性劑中的甲基纖維素⑽C)之重量 籲 百分比濃度進一步限縮為介於O.lppm〜5ppm、且該 C18〜22經烧基經丙基瓜兒膝之重量百分比滚度進一步限 缩為介於lppm〜lOOppm、且該羧甲基織維素鈉(CMC_Na) 之重量百分比濃度進一步限縮為介於2Qppm〜300ρρτη 時，依據實驗證明，本發明之钱刻方法的金字塔群結構覆 蓋率更可進一步提高到95%以上、蝕刻量將介於 6μιη〜20μιη、且反射率及目視均勻性也都進一步提高，而 能獲得更佳的制絨效果。 • 具體實施例二： 在製程溫度介於60°C〜80°C、且製程時間介於 lOmin〜25min之間的製程條件下時，使用以下所述的钮刻 液配方來實施本發明之蚀刻方法將可得到良好的制絨效 果。該蝕刻液之配方包括了 ：水溶性鹼性物質之濃度為 1°/^15%、矽氧化合物濃度為0·001°/σ-10%、以及界面活 性劑。並且，該界面活性劑更包括了 ：選自第一成分群的 黃原膠(X.G)濃度為介於50ppm〜lOOOppm、以及選自第 二成分群的C18〜22羥烷基羥丙基瓜兒膠濃度為介於 201211214 lppm〜200ppm與羧甲基織維素鈉(CMC_Na)濃度為介 於20ppm〜lOOOppm，但是該C18〜22羥烷基羥丙基瓜兒 膠與該羧甲基纖維素鈉(CMC-Na)兩者合計之重量百分比 濃度為小於lOOOppm»依據實驗證明，在此一蝕刻液配方 以及製程條件下所進行的蝕刻製程，其覆蓋率可達到80〇/〇 以上、蚀刻量介於4 μιη〜20μιη之間、反射率低於170/〇、 且發基材表面目視均勻性良好的效果。 然而’當把界面活性劑中的黃原膠(X.G)之重量百分 比濃度進一步限縮為介於50ppm〜l〇〇ppm、且該C18〜22 羥烷基羥丙基瓜兒膠之重量百分比濃度進一步限縮為介 於lppm〜lOOppm、且該羧甲基纖維素鈉(CMC-Na)之重 量百分比渡度進一步限縮為介於2〇ppm〜300ppm時，依 據實驗證明，其覆蓋率更可進一步提高到95%以上、蝕刻 量將介於6μιη〜20μιη、且反射率及目視均句性也都進一步 提高，而能獲得更佳的制絨效果。 唯以上所述之實施例不應用於限制本發明之可應用 範圍，本發明之保護範圍應以本發明之申請專利範圍内容 所界定技術精神及其均等變化所含括之範圍為主者。即大 凡依本發明申請專利範圍所做之均等變化及修飾，仍將不 失本發明之要義所在，亦不脫離本發明之精神和範圍，故 都應視為本發明的進一步實施狀況。 【圖式簡單說明】 圊一為依據本發明之姓刻方法具趙實施例一所完成之 矽基材表面金字塔群結構的放大側視示意圖。 201211214 圖二為依據本發明之蝕刻方法具體實施例一所完成之 矽基材表面金字塔群結構的上視示意圖。 圖三為依據習用技術蝕刻方法所完成之矽基材表面金 字塔群結構的放大側視示意圖。 圖四為依據習用技術蝕刻方法所完成之矽基材表面金 字塔群結構的上視示意圖。 【主要元件符號說明】Cellulose; referred to as HMHEC), hydroxymethylbutyl cellulose, methyl ethyl 2-hydroxyethyl cellulose, Cellulose propionate, Cellulose acetate, Hydroxypropyl methyl cellulose (HPMC), Hydroxypropylcellulose (HPC), Chitin, Garrageenan, Locust bean gum, Pectin, Taragum, Arabiaggum, Gellen gum, Fiber, brown algae, fragrant polydamine, Cordyceps, sodium alginate (Sodium Alginate), or the extraction of other kinds of polysaccharide substances from the plant Lu, can be used as an example of the surfactant in the button engraving of the present invention, but the content and concentration are still able to obtain good texturing. One of the keys to the effect. In the present invention, the polysaccharide material contained in the etching solution may have different functions and effects in the etching process depending on the composition. Therefore, the present invention can roughly divide the above-mentioned various multi-audio substances into two groups, which are simply referred to as a first component group and a second component group, respectively, depending on the different effects that different polysaccharide substances can provide. In a preferred embodiment, the polysaccharide material in the surfactant of the invention of φ is a mixture comprising at least one first component selected from the first component group and from the second component group. At least one second component selected. The first component group includes the following polysaccharide materials: methyl worm (MC), xanthan gum (χ·〇), hydrophobic modified hydroxyethyl cellulose, thiol hydroxyethyl woven , propionate propionate, cellulose acetate, hydroxypropyl methylcellulose, hydroxypropyl vesin, chitin, carrageenan, locust bean gum, pectin, tara gum, gum arabic, knot Lan gum, meal weaving. The polysaccharide material in the first 12 201211214 group may have the effect of increasing the etching selectivity of the 100/111 phase in the etching process, that is, it helps to form a pyramid-like protrusion on the surface of the tantalum substrate. When the concentration of the polysaccharide material of the first component group contained in the etching solution is increased, 'the coverage of the pyramid group structure on the surface of the crucible substrate (that is, the coverage integrity) can be improved, but at the same time, the etching rate is also obtained. Conversely, when the concentration of the polysaccharide material contained in the first component group in the etching solution is decreased, the coverage is also lowered; therefore, it is necessary to determine an optimized concentration range. In the present invention, the weight percentage of the first component in the etching solution is less than 1000 ppm, which is an achievable concentration range, and the preferred range is to be described later. The second component group comprises the following polysaccharide materials: C18~22 hydroxyalkyl hydroxypropyl guar gum, hydroxypropyl guar gum, carboxymethyl guar gum, carboxymethyl hydroxypropyl group Guar gum, hydrolyzed guar gum, sodium carboxymethyl cellulose, fucoidan, shiitake mushroom, cordyceps polysaccharide, sodium alginate. The polysaccharide material in the second component group can have the effect of increasing the rate at which the reaction bubble exits the wafer during the etching process. When the concentration of the polysaccharide substance of the second component group contained in the etching liquid is increased, the rate at which the reaction bubbles are released from the wafer is increased, but the etching amount is decreased, and the coverage is lowered due to the suppression of the reaction; therefore, an optimization is determined. The concentration range is necessary. In the present invention, the concentration of the second component in the etching solution is less than 1000 ppm, which is an executable concentration range, and the preferred range will be described later. Embodiment 1: When the process temperature is between 6 (TC~80 ° C and the process time is between 10 min and 25 min), the etching of the present invention is carried out by using the etching 201211214 liquid formulation described below. The method can obtain a good texturing effect. The formulation of the etching solution comprises: a concentration of a water-soluble alkaline substance of 1% to 15%, a concentration of a rare oxygen compound of 0.001% to 10%, and a surfactant. The surfactant further comprises methyl cellulose (MC) selected from the group consisting of the first component group having a concentration of 0.1 ppm to 200 ppm, and C18 22 selected from the group of the second component. The soil has an alkalinity of from ippm to 200 ppm and sodium carboxymethyl cellulose (CMC-Na) at a concentration of from 20 ppm to 1000 ppm; but the C18-22 hydroxyalkyl hydroxypropyl guar gum and the sodium methylcellulose (CMC) -Na) The total concentration of the two is less than 1000 ppm. According to experiments, the etching process performed under the etching solution formulation and the process conditions can obtain the coverage of the pyramid group structure on the surface of the germanium substrate to 80. More than %, etching amount (etching depth) is between 4μπι~20μι Between the D8 reflectometer of Lihua Company, the surface reflectance of the ruthenium substrate is less than 17%, and the surface uniformity of the ruthenium substrate is good (that is, the size and distribution of the pyramid structure are uniform). The effect and quality of the cashmere have been accepted by many manufacturers in the solar cell production industry and are considered to be good products. Please refer to the first and second stipulations respectively. An enlarged side view and a top view of the structure of the surface pyramid group 2 of the substrate 1. As can be seen from FIG. 1 and FIG. 2, in the first embodiment of the etching method of the present invention, a pyramid group which is good and uniform (including uniform size and uniform distribution) can be obtained. 2 coverage, the angle between the inclined surface of the structure of the respective pyramid 21 and the surface of the crucible substrate is between 45 < • ~, and the width and width are mostly between private m, also because The size of the pyramid group 2 is uniform, so the overall reflectivity can be further reduced. 201211214 Relatively, please refer to the third and fourth figures, respectively, according to the etching method of the conventional technology. Wei Cai Table © enlarged side view of the pyramid group structure and top view®. If the traditional isopropanol is used as a surfactant or an etchant with a bad formulation, the resulting etched result will be It will be different from Figure 2 and Figure 4. Not only the size of the individual pyramids 31 and 32 is very large, but in some areas 4, the shortcomings of insufficient pyramid group coverage may occur, resulting in an increase in the non-performing rate. The weight percentage of methylcellulose (10)C) in the surfactant is further limited to between 0.1 ppm and 5 ppm, and the C18-22 is further reduced by the weight percentage of the propyl guar For the concentration range of lppm~lOOppm, and the concentration of the sodium carboxymethyl cellulose (CMC_Na) is further limited to 2Qppm~300ρρτη, according to experiments, the pyramid group structure coverage of the money engraving method of the invention Further, it can be further increased to 95% or more, the etching amount will be between 6 μm and 20 μm, and the reflectance and visual uniformity are further improved, and a better texturing effect can be obtained. • Specific Example 2: When the process temperature is between 60 ° C and 80 ° C and the process time is between 10 min and 25 min, the etching process of the present invention is carried out using the button engraving recipe described below. The method will give a good texturing effect. The formulation of the etching solution includes a water-soluble alkaline substance having a concentration of 1 ° / 15%, a concentration of the oxime compound of 0. 001 ° / σ - 10%, and an interfacial activator. Moreover, the surfactant further comprises: a C18~22 hydroxyalkyl hydroxypropyl guar selected from the group consisting of a first component group having a xanthan gum (XG) concentration of 50 ppm to 1000 ppm, and a second component group selected from the group consisting of a second component group. The gel concentration is between 201211214 lppm~200ppm and the concentration of sodium carboxymethyl cellulose (CMC_Na) is between 20ppm~lOOppm, but the C18~22 hydroxyalkyl hydroxypropyl guar gum and the sodium carboxymethyl cellulose (CMC-Na) The total weight percentage concentration of the two is less than 1000 ppm. According to the experiment, the etching process performed under the etching solution formulation and the process conditions can reach a coverage of 80 〇/〇 or more. Between 4 μm and 20 μm, the reflectance is less than 170/〇, and the surface of the substrate is visually uniform. However, when the concentration of xanthan gum (XG) in the surfactant is further reduced to 50 ppm to 1 ppm, and the concentration of the C18 to 22 hydroxyalkyl hydroxypropyl guar gum is Further limited to between 1 ppm and 100 ppm, and the weight percentage of the sodium carboxymethyl cellulose (CMC-Na) is further reduced to between 2 〇 ppm and 300 ppm, according to experiments, the coverage is more Further, the etching amount is increased to 95% or more, the etching amount is between 6 μm and 20 μm, and the reflectance and the visual uniformity are further improved, and a better texturing effect can be obtained. The above-mentioned embodiments are not intended to limit the scope of application of the present invention, and the scope of the present invention should be based on the technical spirit defined by the content of the patent application scope of the present invention and the scope thereof. It is to be understood that the scope of the present invention is not limited by the spirit and scope of the invention, and should be considered as a further embodiment of the invention. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an enlarged side elevational view showing the pyramid structure of the surface of the crucible substrate completed by the first embodiment in accordance with the present invention. 201211214 Fig. 2 is a top plan view showing the pyramid structure of the surface of the tantalum substrate according to the first embodiment of the etching method of the present invention. Fig. 3 is an enlarged side elevational view showing the structure of the surface of the crucible substrate on the surface of the crucible substrate according to the conventional etching method. Figure 4 is a top plan view showing the structure of the surface group of the crucible substrate according to the conventional etching method. [Main component symbol description]
1〜矽基材 2〜金字塔群 21、31、32〜金字塔 4〜區域1 ~ 矽 substrate 2 ~ pyramid group 21, 31, 32 ~ pyramid 4 ~ area
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