一種低蝕刻的去除光阻殘留物的清洗液Low-etching cleaning solution for removing photoresist residue
本發明涉及一種低蝕刻的去除光阻蝕刻殘留物的清洗液。The present invention relates to a low etch cleaning fluid that removes photoresist residues.
在通常的半導體製造工藝中，通過在一些材料的表面上形成光阻的掩膜，曝光後進行圖形轉移，在得到需要的圖形之後，進行下一道工序之前，需要剝去殘留的光阻。在這個過程中要求完全除去不需要的光阻，同時不能腐蝕任何基材。 目前，光阻清洗液主要由極性有機溶劑、強鹼和/或水等組成，通過將半導體晶片浸入清洗液中或者利用清洗液沖洗半導體晶片，去除半導體晶片上的光阻。含水體系的清洗液，如JP1998239865公開了一種組成是四甲基氫氧化銨（TMAH）、二甲基亞碸（DMSO）、1,3-二甲基-2-咪唑烷酮（DMI）和水的清洗液。將晶片浸入該清洗液中，於50~100℃下除去金屬和電介質基材上的20μm以上的光阻；其對半導體晶片基材的腐蝕略高，且不能完全去除半導體晶片上的光阻，清洗能力不足；又如US5529887公開了由氫氧化鉀（KOH）、烷基二醇單烷基醚、水溶性氟化物和水等組成鹼性清洗液，將晶片浸入該清洗液中，在40~90℃下除去金屬和電介質基材上的光阻。其對半導體晶片基材的腐蝕較高，並且在某些限制金屬離子含量的晶圓清洗條件下，含有鉀離子的清洗液無法使用。而非含水體系的清洗液，如US5480585公開了一種組成是乙醇胺、環丁碸或二甲亞碸、鄰苯二酚的清洗液，能在40~120℃下除去金屬和電介質基材上的光阻，對金屬基本無腐蝕。又如US2005119142公開了一種含有烷氧基的聚合物、二丙二醇烷基醚、N-甲基吡咯烷酮和甲基異丁基酮的非水性清洗液。該清洗液可以同時適用於正性光阻和負性光阻的清洗。 隨著半導體的快速發展，特別是凸球封裝領域的發展，對光阻殘留物的清洗要求也相應提高；主要是在單位面積上引腳數（I/O）越來越多，光阻的去除也變得越來越困難。由此可見，尋找更為有效的光阻清洗液是該類光阻清洗液努力改進的優先方向。一般而言，提高鹼性光阻清洗液的清洗能力主要是通過提高清洗液的鹼性、選用更為有效的溶劑體系、提高操作溫度和延長操作時間幾個方面來實現的。但是，提高清洗液的鹼性和操作溫度以及延長清洗時間往往會增加對金屬的腐蝕。一般而言，在凸點封裝領域涉及的金屬主要是銀、錫、鉛和銅四種金屬。近來，為了進一步降低成本提高良率，一些封裝測試廠商開始要求光阻清洗液也能進一步抑制金屬鋁的腐蝕。為了適應新的形勢，必須開發出一類光阻去除能力強，金屬鋁相容的清洗液。In a conventional semiconductor manufacturing process, by forming a photoresist mask on the surface of some materials, pattern transfer after exposure, after obtaining the desired pattern, it is necessary to remove the residual photoresist before proceeding to the next process. In this process it is required to completely remove the unwanted photoresist while not corroding any substrate. At present, the photoresist cleaning liquid is mainly composed of a polar organic solvent, a strong alkali, and/or water, and the photoresist on the semiconductor wafer is removed by immersing the semiconductor wafer in the cleaning liquid or rinsing the semiconductor wafer with the cleaning liquid. A cleaning solution for aqueous systems, such as JP1998239865, discloses a composition of tetramethylammonium hydroxide (TMAH), dimethyl hydrazine (DMSO), 1,3-dimethyl-2-imidazolidinone (DMI) and water. Cleaning solution. The wafer is immersed in the cleaning solution to remove photoresist of 20 μm or more on the metal and dielectric substrate at 50 to 100 ° C; the etching of the semiconductor wafer substrate is slightly higher, and the photoresist on the semiconductor wafer cannot be completely removed. Insufficient cleaning ability; and as disclosed in US Pat. No. 5,529,887, an alkaline cleaning solution consisting of potassium hydroxide (KOH), alkyl glycol monoalkyl ether, water-soluble fluoride and water, etc., is immersed in the cleaning solution at 40~ The photoresist on the metal and dielectric substrates was removed at 90 °C. The corrosion of the semiconductor wafer substrate is high, and the cleaning solution containing potassium ions cannot be used under certain wafer cleaning conditions that limit the metal ion content. A cleaning solution other than an aqueous system, such as US Pat. No. 5,480, 585, discloses a cleaning liquid having the composition of ethanolamine, cyclobutyl hydrazine or dimethyl hydrazine, catechol, capable of removing light on metal and dielectric substrates at 40 to 120 ° C. Resistance, basically no corrosion to metal. Further, as disclosed in US2005119142, a non-aqueous cleaning solution comprising an alkoxy group-containing polymer, dipropylene glycol alkyl ether, N-methylpyrrolidone and methyl isobutyl ketone is disclosed. The cleaning solution can be applied to both positive and negative photoresist cleaning. With the rapid development of semiconductors, especially in the field of bump ball packaging, the cleaning requirements for photoresist residues have also increased accordingly; mainly in the number of pins per unit area (I / O), photoresist Removal has also become more and more difficult. It can be seen that finding a more effective photoresist cleaning solution is a priority for the improvement of such photoresist cleaning liquids. In general, improving the cleaning ability of the alkaline photoresist cleaning solution is mainly achieved by improving the alkalinity of the cleaning solution, selecting a more effective solvent system, increasing the operating temperature, and prolonging the operation time. However, increasing the alkalinity and operating temperature of the cleaning fluid and prolonging the cleaning time tend to increase corrosion of the metal. In general, the metals involved in the field of bump packaging are mainly silver, tin, lead and copper. Recently, in order to further reduce the cost and increase the yield, some package test manufacturers have begun to require the photoresist cleaning liquid to further inhibit the corrosion of the metal aluminum. In order to adapt to the new situation, it is necessary to develop a kind of cleaning liquid with strong photoresist removal ability and metal aluminum compatibility.
本發明的目的是為了提供一種有效地去除光阻殘留物的清洗液及其組成。該清洗液在有效去除晶圓上的光阻殘留物的同時，對於基材如金屬鋁、銅等基本無腐蝕，在半導體晶片清洗等領域具有良好的應用前景。 該清洗液含有： i. 季胺氫氧化物0.1-6%；優選0.5-4% ii. 醇胺0.1-40%，優選0.5-25% iii.水1-20%，優選3-10% iv. C2
-C6
多元醇0.1~8%，優選0.2-4% v. 硫脲及其衍生物0.1-5%，優選 0.2-2% vi.餘量是有機溶劑 上述含量均為重量百分比(品質百分比)含量；這種去除光阻殘留物的清洗液不含有羥胺、氟化物及氧化劑。 本發明中，所述季銨氫氧化物為四甲基氫氧化銨、四乙基氫氧化銨、四丙基氫氧化銨、四丁基氫氧化銨、十六烷基三甲基氫氧化銨和苄基三甲基氫氧化銨中的一種或多種。 本發明中，所述醇胺為單乙醇胺、N-甲基乙醇胺、二乙醇胺、三乙醇胺、異丙醇胺、乙基二乙醇胺、N，N-二乙基乙醇胺、N-(2-氨基乙基)乙醇胺和二甘醇胺。優選為單乙醇胺、三乙醇胺及兩者的混合物。 本發明中，所述C2
-C6
多元醇為乙二醇、1,2-丙二醇、丙三醇、1，4-丁二醇、季戊四醇、木糖醇、葡萄糖、果糖、甘露醇、山梨醇中的一種或多種。優選為1，2-丙二醇、丙三醇、木糖醇中的一種或多種。 本發明中，所述硫脲及其衍生物為硫脲、N-甲基硫脲、1,3-二甲基硫脲、1,3-二乙基硫脲、硫代氨基脲、亞乙基硫脲、脒基硫脲、2-乙內醯硫脲、苯甲醯基硫脲、月桂醯基硫脲中的一種或多種。其中，優選為硫脲、N-甲基硫脲、亞乙基硫脲中的一種或多種。 本發明中，所述有機溶劑為亞碸、碸、咪唑烷酮、吡咯烷酮、咪唑啉酮、醯胺和醇醚中的一種或多種；所述亞碸較佳為二甲基亞碸和甲乙基亞碸中的一種或多種；所述碸較佳為甲基碸、環丁碸中的一種或多種；所述咪唑烷酮較佳的為2-咪唑烷酮和1,3-二甲基-2-咪唑烷酮中的一種或多種；所述吡咯烷酮較佳為N-甲基吡咯烷酮和N-環己基吡咯烷酮中的一種或多種；所述咪唑啉酮較佳為1,3-二甲基-2-咪唑啉酮；所述醯胺較佳的為二甲基甲醯胺和二甲基乙醯胺中的一種或多種；所述醇醚較佳為二乙二醇單丁醚和二丙二醇單甲醚中的一種或多種。 本發明中的清洗液，可以在25℃至80℃下清洗晶圓上的光阻殘留物。具體方法如下：將含有光阻殘留物的晶圓浸入本發明中的清洗液中，在25℃至80℃下浸泡合適的時間後，取出漂洗後用高純氮氣吹乾。 本發明的積極進步效果在於： 1、本發明的清洗液通過C2
-C6
多元醇和硫脲及其衍生物的複配效應，能夠有效去除晶圓上的光阻殘留物的同時，實現了對基材如金屬鋁、銅等基本無腐蝕。 2、本發明的清洗液在去除晶圓上的光阻具有良好的清洗效果，且使用溫度範圍廣，在半導體晶片清洗等領域具有良好的應用前景。It is an object of the present invention to provide a cleaning solution and composition thereof that effectively removes photoresist residues. The cleaning solution can effectively remove the photoresist residues on the wafer, and has substantially no corrosion to the substrate such as metal aluminum, copper, etc., and has a good application prospect in the field of semiconductor wafer cleaning and the like. The cleaning solution contains: i. quaternary ammonium hydroxide 0.1-6%; preferably 0.5-4% ii. Alkanolamine 0.1-40%, preferably 0.5-25% iii. Water 1-20%, preferably 3-10% iv C 2 -C 6 polyol 0.1-8%, preferably 0.2-4% v. Thiourea and its derivatives 0.1-5%, preferably 0.2-2% vi. The balance is an organic solvent, the above contents are all by weight ( % by mass); this cleaning solution that removes photoresist residues does not contain hydroxylamine, fluoride and oxidizing agents. In the present invention, the quaternary ammonium hydroxide is tetramethylammonium hydroxide, tetraethylammonium hydroxide, tetrapropylammonium hydroxide, tetrabutylammonium hydroxide, cetyltrimethylammonium hydroxide. And one or more of benzyltrimethylammonium hydroxide. In the present invention, the alcohol amine is monoethanolamine, N-methylethanolamine, diethanolamine, triethanolamine, isopropanolamine, ethyldiethanolamine, N,N-diethylethanolamine, N-(2-aminoethyl) Base) ethanolamine and diglycolamine. Preferred are monoethanolamine, triethanolamine, and mixtures of the two. In the present invention, the C 2 -C 6 polyol is ethylene glycol, 1,2-propylene glycol, glycerol, 1,4-butanediol, pentaerythritol, xylitol, glucose, fructose, mannitol, sorbus One or more of the alcohols. It is preferably one or more of 1,2-propanediol, glycerol, and xylitol. In the present invention, the thiourea and its derivatives are thiourea, N-methylthiourea, 1,3-dimethylthiourea, 1,3-diethylthiourea, thiosemicarbazide, and ethylene One or more of thiourea, thiol thiourea, 2-ethyl thiourea, benzhydrin thiourea, and lauryl thiourea. Among them, one or more of thiourea, N-methylthiourea, and ethylene thiourea are preferred. In the present invention, the organic solvent is one or more of an anthracene, an anthracene, an imidazolidinone, a pyrrolidone, an imidazolidinone, a guanamine, and an alcohol ether; and the hydrazine is preferably a dimethyl hydrazine and a methyl ethyl group. One or more of the hydrazines; the hydrazine is preferably one or more of methyl hydrazine and cyclobutyl hydrazine; and the imidazolidinone is preferably 2-imidazolidinone and 1,3-dimethyl- One or more of 2-imidazolidinone; the pyrrolidone is preferably one or more of N-methylpyrrolidone and N-cyclohexylpyrrolidone; the imidazolidinone is preferably 1,3-dimethyl- 2-imidazolidinone; the guanamine is preferably one or more of dimethylformamide and dimethylacetamide; the alcohol ether is preferably diethylene glycol monobutyl ether and dipropylene glycol. One or more of monomethyl ether. In the cleaning liquid of the present invention, the photoresist residue on the wafer can be cleaned at 25 ° C to 80 ° C. The specific method is as follows: the wafer containing the photoresist residue is immersed in the cleaning liquid in the present invention, and immersed at 25 ° C to 80 ° C for a suitable period of time, taken out and rinsed, and then blown dry with high-purity nitrogen gas. The positive progress of the present invention is as follows: 1. The cleaning solution of the present invention can effectively remove the photoresist residue on the wafer by the compounding effect of the C 2 -C 6 polyol and the thiourea and its derivatives, and realizes Substantially non-corrosive to substrates such as metallic aluminum, copper, and the like. 2. The cleaning liquid of the invention has good cleaning effect on removing the photoresist on the wafer, and has a wide temperature range, and has good application prospects in the field of semiconductor wafer cleaning and the like.
下面通過具體實施例進一步闡述發明的優點，但本發明的保護範圍不僅僅局限於下述實施例。 本發明所用試劑及原料均市售可得。本發明的清洗液由上述成分簡單均勻混合即可製得。 表1實施例（Examples）中的清洗液的組分和含量
表2對比例清洗液的組分和含量
為了進一步考察該類清洗液的清洗情況，本發明採用了如下技術手段：即將晶圓微球植入工藝中凸球已經電鍍完成後含有光阻殘留物的晶圓，分別浸入清洗液中在25℃至80℃下利用恒溫振盪器以約60轉/分的振動頻率振盪30~120分鐘，然後經漂洗後用高純氮氣吹乾。光阻殘留物的清洗效果和清洗液對晶片的腐蝕情況如表3和表4所示。 效果實施例1 表3實施例8、12和對比例的晶圓清洗情況
光阻殘留物的清洗效果如表3所示。從表3，對比例8-1與實施例8可以看出：硫脲及其衍生物未加入，把未加入的量全部補加到C2
-C6
多元醇上，其它組分一樣且操作條件相同的條件下，驗證了硫脲及其衍生物的加入有利於金屬鋁和銅的腐蝕的抑制，雖然兩者對光阻的清洗沒有看出明顯差別，但對比例8-1對金屬鋁和銅的腐蝕抑制沒有實施例8好。對比例8-2和實施例8的對比：將C2
-C6
多元醇未加入的量全部補在硫尿素及其衍生物上，驗證了C2
-C6
多元醇的加入與硫脲衍生物具有複配效應，二者一起複配可以實現對金屬銅鋁的保護。對比例8-3與實施例8的對比：二者都不加對金屬的腐蝕更嚴重，進一步驗證了C2
-C6
多元醇和硫尿素衍生物複配對金屬的保護作用。 對比例12-1、12-2、12-3與實施例12可以看出：同對比例8-1、8-2、8-3與實施例8體現出了相同的規律。 效果實施例2 表4部分實施例和對比例的晶圓清洗情況
從表4，對比例15-1與實施例15可以看出：其它組分一樣且操作條件相同的條件下，將硫脲及其衍生物替換成常規氮唑類衍生物之後，雖然兩者對光阻的清洗沒有看出明顯差別，但對比例15-1對金屬鋁和銅的腐蝕抑制沒有實施例15好。對比例15-2和實施例15的對比，進一步驗證了硫脲及其衍生與C2
-C6
多元醇二元複配，比常規氮唑類衍生物實現了更好的金屬保護。 部分實施例和對比例15-1、15-2、15-3可以看出，本發明的清洗液對有光阻殘留物的晶圓具有良好的清洗效果，且使用溫度範圍廣。 應當理解的是，本發明所述wt%均指的是重量(品質)百分含量。 以上對本發明的具體實施例進行了詳細描述，但其只是作為範例，本發明並不限制於以上描述的具體實施例。對於本領域技術人員而言，任何對本發明進行的等同修改和替代也都在本發明的範疇之中。因此，在不脫離本發明的精神和範圍下所作的均等變換和修改，都應涵蓋在本發明的範圍內。The advantages of the invention are further illustrated by the following specific examples, but the scope of the invention is not limited only to the embodiments described below. The reagents and starting materials used in the present invention are commercially available. The cleaning liquid of the present invention can be obtained by simply and uniformly mixing the above components. Table 1 The composition and content of the cleaning solution in the Examples Table 2 Composition and content of the comparative cleaning solution In order to further investigate the cleaning condition of the cleaning liquid, the present invention adopts the following technical means: the wafer containing the photoresist residue after the convex ball has been electroplated in the process of implanting the wafer microspheres, respectively immersed in the cleaning liquid at 25 The mixture was shaken at a vibration frequency of about 60 rpm for 30 to 120 minutes at a temperature of from ° C to 80 ° C, and then rinsed and dried with high-purity nitrogen gas. The cleaning effect of the photoresist residue and the corrosion of the cleaning solution on the wafer are shown in Tables 3 and 4. Effect Example 1 Table 3 Example wafer cleaning conditions of Examples 8, 12 and Comparative Examples The cleaning effect of the photoresist residue is shown in Table 3. From Table 3, Comparative Example 8-1 and Example 8, it can be seen that thiourea and its derivatives are not added, and all the unadded amounts are added to the C 2 -C 6 polyol, and the other components are the same and operated. Under the same conditions, it was verified that the addition of thiourea and its derivatives was beneficial to the corrosion inhibition of aluminum and copper. Although there was no significant difference between the two for the cleaning of the photoresist, the comparative example 8-1 was for aluminum and copper. The corrosion inhibition was not as good as in Example 8. Comparison of Comparative Example 8-2 with Example 8: The amount of C 2 -C 6 polyol not added was all added to sulfur urea and its derivatives, and the addition of C 2 -C 6 polyol and thiourea derivative were verified. The material has a compounding effect, and the two can be combined to realize the protection of the metal copper and aluminum. Comparative Example 8-3 was compared with Example 8: neither of them corroded the metal more seriously, and further verified the protective effect of the C 2 -C 6 polyol and the thiourea derivative on the metal. Comparative Examples 12-1, 12-2, 12-3 and Example 12 show that the same ratios are exhibited in the same comparative examples 8-1, 8-2, and 8-3. Effect Example 2 Table 4 Partial Example and Comparative Example Wafer Cleaning From Table 4, Comparative Example 15-1 and Example 15 can be seen that after the other components are the same and the operating conditions are the same, after replacing the thiourea and its derivative with the conventional azole derivative, although the two are No significant difference was observed in the cleaning of the photoresist, but the corrosion inhibition of the metal aluminum and copper in Comparative Example 15-1 was not as good as in Example 15. 15-2 and contrast ratio of Example 15, further verified thiourea and derivatives thereof and polyhydric C 2 -C 6 diol compound, to achieve a better protection than a conventional metal azole derivatives. As can be seen from some of the examples and comparative examples 15-1, 15-2, and 15-3, the cleaning liquid of the present invention has a good cleaning effect on a wafer having a photoresist residue, and has a wide temperature range of use. It should be understood that the wt% of the present invention refers to the weight (quality) percentage. The specific embodiments of the present invention have been described in detail above, but are merely exemplary, and the invention is not limited to the specific embodiments described above. Any equivalent modifications and substitutions to the invention are also within the scope of the invention. Accordingly, equivalents and modifications may be made without departing from the spirit and scope of the invention.