201104703 六、發明說明： 【發明所屬之技術領域】 本發明係涉及用於薄膜光伏電池的聚合物厚膜 導體組合物。在-個實例中，PTF銀組合物做為透電、 氧化物（TCO)頂部的一個絲網印刷 P刷柵極運用之，例如銦氧 化錫。 【發明内容】 本發明係涉及-種聚合物厚臈組合物，該組合 ： ⑷銀薄片；（b)有機介質。該有機介質包括⑴有機5 魅合劑；（2)溶劑；以及（3)印刷㈣。在處理該也I物 時’要確保處理的時間和溫度能夠移除所有溶劑。 約佔組合物總重量76.0_92.0%，苯氣基樹脂約佔組合物构 重量2.〇-6.5%，有機介質約佔組合物總重量8.0_24.0%， 、本發明進-步涉及利用此類組合物在薄膜光伏電二 t電極柵的方法，以及由此類方法與/或組合物形成的製 1¾ ° 衣 【實施方式】 2發明針對薄膜光伏（pv)電池所使用的聚合物厚膜銀組 ^ Θ力以說明。利用聚合物厚膜銀组合物來改進電池電效 型的做法。Ag的柵狀®案印刷在透明導電氧化物 、頂部。吸光半導體通常是薄膜pv電池的特徵，例 錮鎵二"（CIGS)或碲化锡等。此—特徵使得 .首、 '池與傳統晶體硅PV電池有所區別。薄膜係指半 .、旱度通常半導體厚度為2微米，或指晶體硅的厚 141940.doc 201104703 度30-50微米。薄膜Pv電池與晶體硅pv電池的另一個區別 在於所涉及的溫度限制。因為薄膜中所使用的半導體與/ 或基底不能耐高溫，因此薄臈電池必須在2〇〇亡以下的環 ^中處理之。傳統的晶體硅pv電池處理溫度或許可高達 _c。因此’必須將PTF Ag組合物用作頂部電極拇，因 為PTF組合物自身要維持穩定狀態，其最高溫度 到達20〇t。 而。彳膜組合物包括-個功能相，該功能項能夠 合物適當電功能特性。功能相包括分散在有機介質 一般二力㈣：末，而該有機介質則充當功能相的載體。 電功能特性。但是對於聚人：厘燒盡有機物’進而賦予其 屬^物U、 厚膜而言，乾燥之後有機物 屬，，且D物不可分割的一部份。燃庐 包括提供選擇性的熱處理方心^ ^處理而求或許可 以及其他厚膜技術領域 ；4、固化、回流， 句括厘肢h人a 系人貝熟知的方法。「有機物」 。括尽膜組合物的聚合物或樹脂成分。 厚膜導體組合物的主要成八β八 粉末，該有機介f$以在有機介W中的導電 些成分。 A °物樹脂和溶劑。下文將討論這 A.導電粉末 在一個實例中’本發明厚膜的 體粉末，該導電粉末或〜 物中的導電粉末為導 粉末或是渠等之混合物。匕括Ag金屬粉末、Ag合金金屬 均加以考量。在一個實具^各種粒徑和形狀的金屬粉末 在個貫例中，導電粉末或許可包括任何形 141940.doc 201104703 狀的銀粉末，包括球形 心㈣/專片（棒'錐、板），以及渠 物。在—個實例中’導電粉末可包括銀薄片。 在一個㈣中’導電粉末的粒度分佈可為L微米； 另一個實例中’粒度分佈則為2-10微米。 2在：個實例中’銀顆粒的面積/重量比率落於Ο。。 4犯圍内。在另—個實例中，銀顆粒的面積/重量比率落 ^.3-KOmVg範圍内。在另—個實例中，銀顆粒的面積/ 重量比率則落在〇.4-〇.7m2/g範圍内。 此外，已知可將少量其他金屬添加到銀導體組合物中， 以改善導體的特性。此類金屬的—些範例包括：金、銀、 銅、鎳、鋁、餘、鈀、銦、鎢 '钽、錫、銦、鑭、乱、 硼、釕、鈷、鈦、釔、銪、鎵、硫、鋅、硅、鎂、鋇、 鈽、錄、錯、録、導電性碳，以及這些金屬的多種組合形 f和厚膜組合物領域的其他常用物質。添加額外金屬的重 里最多可佔組合物總重量約1 〇% 〇 在一個實例中，銀薄片重量或許可佔組合物總重量76_ 92%、77-88%或 78-83%。 B.有機介質 通常利用機械混合方式，將粉末與有機介質（載體）混 合，以形成糊狀組合物，稱為「糊劑」，糊劑稠度和流變 性質適於印刷。許多種類的惰性液體可做為有機介質使用 之°有機介質必須使得固體能夠以適當的穩定度在其中分 散。介質的流變性質必須能賦予組合物良好的應用特性。 此類特性包括··固體以適當的穩定度分散、組合物的良好 141940.doc 201104703 〜、性、適當的粘度、觸變性、基底和固體具備適切可 .....良好的乾燥速率，以及足以耐受粗處理的乾燥膜強 度。 聚合物樹脂 量的銀薄片， 個關鍵特性， 可包括笨氧基樹脂’這種樹脂允許承載高重 進而有助於實現薄膜光伏電池中銀電極的兩 即對銦氡化錫基底的良好附著性和低接觸電 曰年;〇 t 在-個實例中，苯氧基樹脂可佔組合物總重量2 0_ 2-2-5.9°/。或2.5-5.7¼。在一個實例中，苯氧基樹脂 可佔組合物總重量1.5-6%。 本領域專業人員可識別適用於聚合物厚膜組合物的溶 J此類’合劑包括乙酸酯和萜烯（terpenes)，例如α-或β-萜 口口醇（alpha-or beta-terpineoi)或其與其他溶劑的混合物， 例如與煤油 '鄰苯二f酸二丁 _、丁基卡必肖、丁基卡必 醇乙酸醋、己二醇以及高彿點醇和醇醋的混合物。在一個 實例中，溶劑可包括選自以下物質的―種或多種組分：二 甘醇乙基醚乙酸酯(卡必醇乙酸酯）' 二元酸酯和C-11酮。 此外在載體中可包括揮發性液體，以便於載體在塗覆到 基底上㈣速硬化。本發a㈣許乡實射，可使用諸如二 醇醚、酮、酯類的溶劑和具有類似沸點（在18(TC至250t； 範圍内)的其他冷劑、以及其混合物。較佳的介質係基於 二醇醚和β·ϋ品醇。對這些溶劑和其他溶劑的各種组合進 行配製，以達到所需的枯度和揮發性需求規範。 雖…糸’祠ρ刷被„忍為是沉積聚合物厚膜銀組合物的常用 方法，但也可採用任何其他的傳統方法，包括模版印刷、 141940.doc 201104703 注射式滴塗或其他沉積或塗覆技術。 在一個實例中，右 "質可佔組合物總重量的8.0. 24·0/〇、10.0-22.0% 或 12,0-21.0%。 個實例中’ Ag與笨氧基樹脂的比率可介於13:1盘 之間。在另—個實例中，〜與笨氧基樹脂的比率可；; 於15:1與3 0:1之間。 厚膜的塗覆 聚合物厚膜銀組合物「 ^ 物也稱為糊劑」，通常將其沉積於 氣體和水分不可渗透的基底之上，例如賤射聚西旨基底。基 ί也可以是柔性材料片材’例如不可渗透的塑料（如聚對 本二甲酸乙二醇醋之類的聚醋），或由塑性片材與沉積其 上的選擇性金屬或電介質層組合所構成的複合材料。在一 個實例中，基底可以為積聚的層，首先是金屬化(不錄鋼) 聚醋，然後是半導體層（例如CIGS)，接下來是薄⑽層， 最後是錢射铜氧化錫。在另一個實例中，以氧化辞取代鋼 乳化錫，作為薄膜太陽能電池的透明導電氧化物（tc〇)。 雖然可採用其他沉積技術，例如模版印刷 '注射式滴塗 或塗覆技術，但採用絲網印刷來沉積聚合物厚膜銀組合物 是較佳的方式。就絲網印刷而言，篩網目尺寸控制沉積厚 膜的厚度。 + 通常沉積厚膜在14〇t下加熱10至15分鐘乾燥之，以形 成薄膜太陽能電池。 以下將利用具體實例進一步討論本發明，但本發明範疇 不受這些實例之限制。 I41940.doc 201104703 範例1 透過將平均粒度為7㈣(範圍為2·15微米）的銀薄片與有 機介質混合，以製備PTF銀電極糊劑，該有機介質由聚声 基趟樹脂(也稱為苯氧基樹脂)所組成，可自抑― 該溶劑 A‘SS〇ciateS公司購得。該樹脂的分子量約為2〇，_。添加銀 薄片之前，使用一種溶劑將苯氧基樹脂完全溶解 為卡必醇乙酸酯（可自Eastman Chemical公司購得） 銀導體C的組成如下： 81.55重量％薄片狀銀 15.53重量％有機介質(23〇重量％苯氧基樹脂 劑） 里里/〇，合 2.92重量％卡必醇乙酸酯溶劑 在行星式攪拌器中，將組合物授拌3〇分鐘，然後將組人 物轉移至三輥磨’使其經歷〇69 MPa(i〇〇磅/平方英吋° 7赂⑽镑/平方英忖）這兩道工序。此時，利用該: = = 為8ί) Ω/_㈣醋的頂部執行銀 回 Ρ刷。使用280目不銹鋼篩網印刷—孕列的 、Γ並將銀糊劑置於_強迫通風烤箱中乾㈣分鐘 奴後測得接觸電阻率為2x10-3 Ω cn^。兩相對照 益 法測量^準組合物（例如銀導體A)，因為標準組合物對咖 的=性差另—個標準產品（例如銀導體B)顯示 =〜的接觸電阻率。銀導體。的接觸電阻率且= 此意外的明顯改進（這也是薄膜p 性），佔甘处机 口物的一個關鍵特 吏4夠破大多數應用系統所採用，並改進PV電池 14I940.doc 201104703 的效率。彙整表如下所示： 附表1 接觸電阻率201104703 VI. Description of the Invention: [Technical Field of the Invention] The present invention relates to a polymer thick film conductor composition for a thin film photovoltaic cell. In one example, the PTF silver composition is used as a screen printed P brush gate on top of a gas permeable, oxide (TCO), such as indium tin oxide. SUMMARY OF THE INVENTION The present invention is directed to a polymer thick bismuth composition comprising: (4) a silver flake; (b) an organic medium. The organic medium comprises (1) an organic 5 mixture; (2) a solvent; and (3) a printing (4). It is necessary to ensure that the time and temperature of the treatment can remove all the solvent when processing the same. About 76.0_92.0% of the total weight of the composition, the benzene-based resin accounts for about 2.5%-6.5% of the composition, and the organic medium accounts for about 8.0-24.0% of the total weight of the composition. Method for utilizing such a composition in a thin film photovoltaic electric two-t electrode grid, and a method for forming a film from such a method and/or composition [Embodiment] 2 Invention for a polymer used for a thin film photovoltaic (pv) battery Thick film silver group ^ Θ force to illustrate. The use of polymer thick film silver compositions to improve battery efficacy. Ag's grid-like case is printed on a transparent conductive oxide, top. The light absorbing semiconductor is usually characterized by a thin film pv battery, such as bismuth gallium " (CIGS) or bismuth telluride. This feature makes the first and the 'cells different from traditional crystalline silicon PV cells. The film refers to a half. The dryness is usually 2 microns in thickness, or the thickness of crystalline silicon is 141940.doc 201104703 degrees 30-50 microns. Another difference between thin film Pv cells and crystalline silicon pv cells is the temperature limitations involved. Since the semiconductor and/or substrate used in the film cannot withstand high temperatures, the thin tantalum cell must be processed in a ring below 2 dead. Conventional crystalline silicon pv batteries handle temperatures up to _c. Therefore, the PTF Ag composition must be used as the top electrode thumb because the PTF composition itself is to maintain a steady state with a maximum temperature of 20 〇t. and. The ruthenium film composition includes a functional phase that is capable of having suitable electrical functional properties. The functional phase consists of being dispersed in an organic medium, generally two (four): the end, and the organic medium acts as a carrier for the functional phase. Electrical function characteristics. However, for the group of people: the liquefied organic matter is further imparted to the genus U, the thick film, the organic matter after drying, and the D object is inseparable. Burning includes the provision of a selective heat treatment square ^ ^ ^ to seek or permit and other thick film technology fields; 4, solidification, reflux, the phrase includes a method known as the human body. "organic matter". The polymer or resin component of the film composition is included. The thick film conductor composition is mainly composed of eight ? eight powders which are electrically conductive in the organic medium W. A ° resin and solvent. This will be discussed below. A. Conductive powder In one example, the bulk powder of the thick film of the present invention, the conductive powder in the conductive powder or the like is a powder or a mixture of channels or the like. The inclusion of Ag metal powder and Ag alloy metal are all considered. In a case where a metal powder of various particle sizes and shapes is used, the conductive powder may include any silver powder of the shape 141940.doc 201104703, including a spherical core (four) / a special piece (rod 'cone, plate), And the canal. In one example, the conductive powder may comprise a silver flake. The particle size distribution of the conductive powder in one (four) may be L micron; in another example, the particle size distribution is from 2 to 10 m. 2 In one example, the area/weight ratio of silver particles falls on Ο. . 4 committed within the fence. In another example, the area/weight ratio of silver particles falls within the range of .3-KOmVg. In another example, the area/weight ratio of silver particles falls within the range of 〇.4-〇.7m2/g. Furthermore, it is known that a small amount of other metals can be added to the silver conductor composition to improve the characteristics of the conductor. Some examples of such metals include: gold, silver, copper, nickel, aluminum, palladium, indium, tungsten 'rhenium, tin, indium, antimony, chaos, boron, antimony, cobalt, titanium, antimony, antimony, gallium. , sulfur, zinc, silicon, magnesium, lanthanum, cerium, recorded, erroneous, recorded, conductive carbon, and various combinations of these metals f and other commonly used materials in the field of thick film compositions. The weight of the additional metal may be up to about 1% by weight based on the total weight of the composition. 〇 In one example, the weight of the silver flakes may be 76_92%, 77-88%, or 78-83% of the total weight of the composition. B. Organic Medium The powder is usually mixed with an organic medium (carrier) by mechanical mixing to form a paste composition called a "paste", and the paste consistency and rheological properties are suitable for printing. Many types of inert liquids can be used as organic media. The organic medium must allow the solids to be dispersed therein with appropriate stability. The rheological properties of the medium must impart good application characteristics to the composition. Such properties include: · Solids dispersed with appropriate stability, good composition 141940.doc 201104703 ~, properties, appropriate viscosity, thixotropy, substrate and solids are suitable ..... good drying rate, and A dry film strength sufficient to withstand rough handling. The amount of polymer resin in the silver flakes, a key feature, may include a stupid oxy-resin, which allows the carrying of high weights to help achieve good adhesion of the silver electrode in the thin-film photovoltaic cell to the indium antimonide tin substrate. Low contact electric enthalpy; 〇t In one example, the phenoxy resin may comprise 2 0-2-2-5.9 °/ of the total weight of the composition. Or 2.5-5.71⁄4. In one example, the phenoxy resin can comprise from 1.5% to 6% by weight based on the total weight of the composition. One skilled in the art can identify solutions suitable for use in polymeric thick film compositions. Such 'mixtures' include acetates and terpenes, such as alpha- or beta-terpineoi. Or a mixture thereof with other solvents, for example with a mixture of kerosene 'o-phthalic acid dibutyl", butyl carbamide, butyl carbitol acetate vinegar, hexane diol, and sorghum and alcoholic vinegar. In one example, the solvent may comprise one or more components selected from the group consisting of diethylene glycol ethyl ether acetate (carbitol acetate) 'dibasic acid esters and C-11 ketones. Further, a volatile liquid may be included in the carrier to facilitate (4) rapid hardening of the carrier onto the substrate. The present invention a (d) Xuxiang real shot, the use of solvents such as glycol ethers, ketones, esters and other similar boiling points (in the range of 18 (TC to 250t; range), and mixtures thereof. Preferred media systems Based on glycol ethers and beta-terpineol, various combinations of these solvents and other solvents are formulated to achieve the desired specification of dryness and volatility. Although...糸'祠ρ刷 is “to be a deposition polymerization” A common method for thick film silver compositions, but any other conventional method may be employed, including stencil printing, 141940.doc 201104703 injection dispensing or other deposition or coating techniques. In one example, right "quality 8.0.24·0/〇, 10.0-22.0% or 12,0-21.0% of the total weight of the composition. In an example, the ratio of Ag to the stupid epoxy resin may be between 13:1. In one example, the ratio of ~ to the stupid epoxy resin can be; between 15:1 and 30:1. The thick film coated polymer thick film silver composition "^ is also known as paste", It is usually deposited on a substrate that is impermeable to gases and moisture, such as a ruthenium-based substrate. It is a sheet of flexible material such as an impermeable plastic (such as polyacetate such as polyethylene terephthalate) or a composite of a plastic sheet and a selective metal or dielectric layer deposited thereon. In one example, the substrate can be an accumulated layer, first a metallized (non-recorded steel) polyacetate, then a semiconductor layer (such as CIGS), followed by a thin (10) layer, and finally a carbon-injected copper tin oxide. In another example, the steel emulsified tin is replaced by an oxidizing word as a transparent conductive oxide (tc) of a thin film solar cell. Although other deposition techniques such as stencil printing 'injection dispensing or coating techniques can be employed, Screen printing to deposit a polymer thick film silver composition is preferred. For screen printing, the mesh size controls the thickness of the deposited thick film. + Usually the thick film is deposited at 14 〇t for 10 to 15 minutes. Drying to form a thin film solar cell. The invention will be further discussed below using specific examples, but the scope of the invention is not limited by these examples. I41940.doc 201104703 Example 1 A silver flake having an average particle size of 7 (four) (range 2.15 μm) is mixed with an organic medium to prepare a PTF silver electrode paste composed of a polyphonic fluorene resin (also referred to as a phenoxy resin). Self-inhibiting - the solvent is commercially available from A'SS〇ciateS. The molecular weight of the resin is about 2 〇, _. Before adding the silver flakes, the phenoxy resin is completely dissolved into carbitol acetate using a solvent. The composition of the silver conductor C is as follows: 81.55 wt% flaky silver 15.53 wt% organic medium (23 wt% phenoxy resin) Lili/〇, 2.92 wt% carbitol acetate Solvent in a planetary mixer, mix the composition for 3 minutes, then transfer the group to a three-roll mill to make it experience 〇69 MPa (i〇〇pounds per square inch° 7 bristle (10) pounds per square inch忖) These two processes. At this point, use the: = = 8 ί) Ω / _ (four) vinegar to perform the silver back Ρ brush. Using a 280 mesh stainless steel screen - pregnant, sputum and silver paste in a forced air oven for dry (four) minutes after the slave measured contact resistivity of 2x10-3 Ω cn ^. The two-phase control method is used to measure the quasi-composition (e.g., silver conductor A) because the standard composition has a poor compatibility with coffee. Another standard product (e.g., silver conductor B) exhibits a contact resistivity of =~. Silver conductor. The contact resistivity and = a significant improvement in this accident (this is also the p-type of the film), a key feature of the machine mouth is enough to break through most applications and improve the efficiency of the PV cell 14I940.doc 201104703 . The summary table is as follows: Schedule 1 Contact Resistivity
對照範例2 透過將平均粒度7叫的銀薄片與範例1所示聚經基峻（苯 氧基樹脂）所組成的有機介質混合，以製備pTF銀電極糊劑 D。所用溶劑與範例1中所使用的溶劑相同（卡必醇乙酸 酯）。D的組成如下所示： 文 70.0重量％薄片狀銀 Μ重量％有機介質⑴』重量％苯氧基樹脂/8ι重量％溶劑） 1 ·〇重量％卡必醇乙酸酯溶劑 依據例1方法，搜拌並輥屋該組合物，同時依據範例1 所述方法，將糊劑絲網印刷並乾燥之，測得接觸電阻率為 8χ10_1 Ω cm2，幾乎比銀導體c差兩個數量級，同時測得 其對ITO的附著性明顯弱於銀導體c。 依據所述方法製備之其他組合物與測量結果如附表2所 不Comparative Example 2 A pTF silver electrode paste D was prepared by mixing an silver flake having an average particle size of 7 with an organic medium composed of a polypyridyl (phenoxy resin) as shown in Example 1. The solvent used was the same as that used in Example 1 (carbitol acetate). The composition of D is as follows: 70.0% by weight of flaky silver iridium, % by weight of organic medium (1) 』% by weight of phenoxy resin / 8 重量% by weight of solvent) 1 · 〇% by weight of carbitol acetate solvent according to the method of Example 1, The composition was mixed and rolled, and the paste was screen printed and dried according to the method described in Example 1, and the contact resistivity was measured to be 8 χ 10 Ω Ω cm 2 , which was almost two orders of magnitude worse than the silver conductor c. Its adhesion to ITO is significantly weaker than that of silver conductor c. Other compositions prepared according to the method and measurement results are as shown in Schedule 2.
141940.doc 201104703 附表2 重量％Ag重量％樹脂 AW樹脂接觸電阻率附著性 (mohm cm2)(對 ITO) 70.0 5.51 1 12.70 8x10-1 1 73.0 6.75 10.81 2x10-1 3 77.5 5.12 15.14 2x10-3 5 81.5 3.57 22.83 1χ10-3 5 87.0 2.99 29.10 1 X10-3 5 依據本說明書所述範例’使用astm膠帶法來測量對 ITO的附著性。將600級膠帶施加到已印刷/乾燥的銀墨圖 案上，然後以連續方式移除膠帶’依據1到5的任意標度來 評量被移除銀墨物質的量，5代表沒有銀墨物質被移除（表 示附著性極佳）。 在本文範例中，透過在透明導電氧化物（錮氧化錫）上印 刷不同間距-系列的線來測量接觸電阻率，在標準條件下 讓銀墨乾燥之，藉由繪製绫的雪 由“ 霄表綠的電阻率與間距的關係圖，使 用傳輸線法計算接觸電阻率， 率。 戠距代表兩倍接觸電阻 141940.doc141940.doc 201104703 Schedule 2 wt% Ag wt% resin AW resin contact resistivity adhesion (mohm cm2) (for ITO) 70.0 5.51 1 12.70 8x10-1 1 73.0 6.75 10.81 2x10-1 3 77.5 5.12 15.14 2x10-3 5 81.5 3.57 22.83 1χ10-3 5 87.0 2.99 29.10 1 X10-3 5 Measure the adhesion to ITO using the astm tape method according to the example described in this specification. Applying grade 600 tape to the printed/dried silver ink pattern and then removing the tape in a continuous manner 'measures the amount of silver ink removed based on any scale from 1 to 5, with 5 representing no silver ink Removed (indicating excellent adhesion). In the example of this paper, the contact resistivity is measured by printing different pitch-series lines on a transparent conductive oxide (tantalum tin oxide), and the silver ink is dried under standard conditions by drawing a hazy snow. The relationship between green resistivity and spacing, using the transmission line method to calculate the contact resistivity, rate. The lay length represents twice the contact resistance 141940.doc