201211322 六、發明說明： 【發明所屬之技術領域】 本發明是有關於一種電鍍液組成，且特別是有關於一 - 種銅電鍵液組成。 【先前技術】 隨著半導體元件尺寸的縮減，銅金屬連線的普及率也 逐漸增加，目前銅製程大部份採用電鍍法來進行。於盲孔 籲 或通孔中沉積銅時，必須要控制銅離子在盲孔底部的析出 速率要大於盲孔外表面上的沉積速率，或者必須要控制銅 離子在通孔中央的沉積速率要大於通孔外表面上的沉積速 率，否則會因孔口電流密度較高，導致電鍍完畢後，在填 充的孔洞中央形成一條縫隙（seam )或是一個空洞（void)。 而空洞與縫隙會影響訊號傳遞速率與降低晶片之信賴度。 一般而言，現今學界與業界的電鍍液配方大多利用添 加多重添加劑，使盲孔孔底的銅沉積速率大於盲孔外表面 • 而產生孔底上移的現象，改善空洞與縫隙的問題。然而， 由於每種添加劑個別皆會受到環境溫度影響，且兩種或兩 種以上添加劑之間，甚至是添加劑與電鍍液中其他成分的 交互作用都會影響到整個電鍍過程。再者，多重添加劑通 常會導致分析的困難，難以達到穩定的品質控制。換句話 說，一旦添加劑種類多，則分析及控制均不易。此外，上 述銅電鐘液應用於印刷電路板（Printed Circuit Board，PCB ) 時，僅能填充盲孔，而無法用於填充通孔。 201211322 【發明内容】 因此’本發明之是在提供一種銅電鍍液組成，可適用 於電鍍填充具有微米級或次微米級通孔或盲孔的基材。 依據本發明一實施方式，一種銅電鍍液組成包含0.6-1 Μ含銅化合物、〇.! _1]ν[羧酸、10- 100 ppm有機含氮雜 環化合物與10 ~~ 1 〇〇 ppm鹵素離子。 根據本發明一實施方式，上述羧酸不單指直鏈羧酸， 亦包含支鏈飽和一元羧酸，含碳數為1 - 10。 • 根據本發明一實施方式，上述含銅化合物為選自由無 水硫酸銅、含水硫酸銅、碳酸銅及氧化銅所組成之群組。 上述含水硫酸鋼為五水合硫酸銅。 根據本發明一實施方式，上述齒素離子為氯離子、溴 離子及峨離子。 根據本發明一實施方式，上述有機含氮雜環化合物為 亂°坐化合物。氮嗤化合物例如為四氮α坐藍（blue tetrazolium chloride )、氣化硝基四氮 π坐藍（Nitro blue tetrazolium • chloride monohydrate )或四硝基四氮唑藍（Tetranitro Blue Tetrazolium)。 【實施方式】 本發明的實施方式中，提出一種銅電鍍液組成，包含 含銅化合物、羧酸、有機含氮雜環化合物與鹵素離子。於 銅電鍍液中，含銅化合物濃度為0.6 - 1 Μ，作為銅離子來 源。含銅化合物為選自由無水硫酸銅、含水硫酸銅、碳酸 銅及氧化銅所組成之群組》根據本發明一實施例，含水硫 201211322 酸銅為五水硫酸銅（CuS〇4 · 5H2〇)。 於本發明之銅電鍍液中，係以羧酸為電解質來源之 一。根據本發明一實施方式，羧酸為含碳數丨_ 1〇的直鏈 或支鏈飽和一元羧酸，例如甲酸、乙酸、丙酸或異丁酸。 羧酸於銅電鍍液中的濃度為0.1 -1M。 由於有機含氮雜環化合物之氮原子易帶正電荷，因此 於電鍍過程中’會受電流分佈的影響而優先聚集吸附在被 鍍面的高電流密度區，進而抑制銅沉積速率。具體而古， φ 通孔或盲孔開口處的電流高於通孔或盲孔内部，使得有機 含氮雜環化合物在通孔或盲孔開口處至其内部的吸附漠度 呈由高至低的梯度分布，進而控制通孔或盲孔内外的銅沉 積速率’藉以減低空洞或縫隙的產生。同時，有機含氮雜 環化合物也可使被鍍面表面平滑，可作為電鍍過程中的平 整劑。有機含氮雜環化合物例如氮唑化合物（Az〇le Compound ) ° 此外，由於竣酸為有機弱酸，不易與有機含氮雜環化 φ 合物反應’可改善銅電鍍液容易沉澱之問題，並可使電錢 後之填孔不會產生夾鍍現象。所謂夾鍍現象係指於填孔中 出現裂痕或雜質的現象或者是板面剝離的情況。 根據本發明一實施方式，上述氮嗤化合物可為四氮峻 藍（blue tetrazolium chloride)、氣化石肖基四氮唾藍（Nitr〇 blue tetrazolium chloride monohydrate)或四硝基四氮i〇坐藍 (Tetranitro Blue Tetrazolium )。其個別化學式依序如下列 式（i)、式（ii)與式（iii)所示。 201211322201211322 VI. Description of the Invention: [Technical Field of the Invention] The present invention relates to a plating liquid composition, and in particular to a copper-electrolyte composition. [Prior Art] As the size of semiconductor components has decreased, the popularity of copper metal wiring has gradually increased. Currently, most copper processes are performed by electroplating. When depositing copper in a blind hole or through hole, it is necessary to control the deposition rate of copper ions at the bottom of the blind hole to be larger than the deposition rate on the outer surface of the blind hole, or it is necessary to control the deposition rate of copper ions in the center of the through hole to be larger than The deposition rate on the outer surface of the via hole may otherwise result in a gap or a void in the center of the filled hole due to the higher current density of the orifice. Cavities and gaps can affect the signal transfer rate and reduce the reliability of the chip. In general, most of the electroplating solution formulations in the academic community and the industry today use the addition of multiple additives to make the copper deposition rate at the bottom of the blind hole larger than the outer surface of the blind hole. The phenomenon of the bottom of the hole is shifted upwards, and the problem of voids and gaps is improved. However, since each additive is individually affected by the ambient temperature, the interaction between the two or more additives, and even the additives and other components in the plating solution, affects the entire plating process. Furthermore, multiple additives often lead to difficulties in analysis and difficult to achieve stable quality control. In other words, once there are many types of additives, analysis and control are not easy. In addition, when the above-mentioned copper bell liquid is applied to a printed circuit board (PCB), it can only fill a blind hole and cannot be used to fill a through hole. 201211322 SUMMARY OF THE INVENTION Accordingly, the present invention is directed to a copper plating bath composition suitable for electroplating a substrate having micron or submicron vias or blind vias. According to an embodiment of the present invention, a copper plating solution composition comprises 0.6-1 Μ copper-containing compound, 〇.! _1] ν [carboxylic acid, 10-100 ppm organic nitrogen-containing heterocyclic compound and 10 ~~ 1 〇〇ppm halogen ion. According to an embodiment of the present invention, the carboxylic acid does not simply mean a linear carboxylic acid, but also a branched saturated monocarboxylic acid having a carbon number of from 1 to 10. • According to an embodiment of the present invention, the copper-containing compound is selected from the group consisting of copper sulfate-free, copper sulfate, copper carbonate, and copper oxide. The above aqueous sulfuric acid steel is copper sulfate pentahydrate. According to an embodiment of the present invention, the dentate ion is a chloride ion, a bromide ion, and a cesium ion. According to an embodiment of the present invention, the organic nitrogen-containing heterocyclic compound is a chaotic compound. The nitrogen ruthenium compound is, for example, blue tetrazolium chloride, Nitro blue tetrazolium chloride monohydrate or Tetranitro Blue Tetrazolium. [Embodiment] In an embodiment of the present invention, a copper plating solution composition comprising a copper-containing compound, a carboxylic acid, an organic nitrogen-containing heterocyclic compound, and a halogen ion is proposed. In the copper plating bath, the copper-containing compound has a concentration of 0.6 - 1 Μ as a copper ion source. The copper-containing compound is selected from the group consisting of anhydrous copper sulfate, aqueous copper sulfate, copper carbonate, and copper oxide. According to an embodiment of the present invention, the water-containing sulfur 201211322 copper acid is copper sulfate pentahydrate (CuS〇4 · 5H2〇). . In the copper plating solution of the present invention, carboxylic acid is used as one of the electrolyte sources. According to one embodiment of the invention, the carboxylic acid is a linear or branched saturated monocarboxylic acid having a carbon number of 丨 1 ,, such as formic acid, acetic acid, propionic acid or isobutyric acid. The concentration of the carboxylic acid in the copper plating bath is 0.1 -1 M. Since the nitrogen atom of the organic nitrogen-containing heterocyclic compound is easily positively charged, it is preferentially aggregated and adsorbed in the high current density region of the plated surface during the electroplating process, thereby suppressing the copper deposition rate. Specifically, the current at the opening of the φ through hole or the blind hole is higher than the inside of the through hole or the blind hole, so that the adsorption moisture of the organic nitrogen-containing heterocyclic compound in the opening of the through hole or the blind hole is high to low. The gradient distribution, which in turn controls the rate of copper deposition inside and outside the via or blind hole, is used to reduce the occurrence of voids or gaps. At the same time, the organic nitrogen-containing heterocyclic compound can also smooth the surface of the plated surface and can be used as a leveling agent in the electroplating process. Organic nitrogen-containing heterocyclic compound such as azole compound (Az〇le Compound) ° In addition, since citric acid is an organic weak acid, it is difficult to react with an organic nitrogen-containing heterocyclic compound, which can improve the problem of easy precipitation of a copper plating solution, and The hole filling after the electric money can be prevented from being pinched. The phenomenon of plate plating refers to the phenomenon of cracks or impurities in the hole filling or the peeling of the plate surface. According to an embodiment of the present invention, the nitrogen hydrazine compound may be blue tetrazolium chloride, Nitr〇blue tetrazolium chloride monohydrate or tetranitrotetrazine i. Tetranitro Blue Tetrazolium ). The individual chemical formulas are shown in the following formulas (i), (ii) and (iii). 201211322
⑴(1)
(iii) 上述之i素離子能有助於使有機含氮雜環化合物與銅 離子形成配位結構，以穩定吸附在銅層上，而且_素離子 201211322 更能加強有機含氮雜環化合物在銅層上的吸附性。根據本 發明一實施例，鹵素離子濃度為10 - 100 ppm。 接下來說明以不同銅電鍍液組成進行電鍍填孔後，再 利用光學顯微鏡（Optical Microscope, OM)觀察基板橫切 面與基板表面的結果。電鍍填孔步驟如下所述。 首先，於電鍍前，先將含銅化合物、電解質與鹵素離 子分別混合均勻，置入哈林試驗槽（Haring cell)中，並打 開空氣幫浦，使用冷卻循環機將溫度維持在28 °C，放置 30分鐘。另準備一預浸杯，内含有機含氮雜環化合物。 所使用的試片為4 X 6平方公分的印刷電路板。試片上 具有直徑為1〇〇 μπι或150 μιη的通孔，通孔深度為230 μπι ’因此通孔深寬比為2.3或1.53。接者，以〇. 5 4 Μ硫酸 清洗試片’去除板面的污染物，並以超音波震盪2分鐘， 去除試片通孔中的氣泡殘留’再以超純水沖洗。 把試片放入已具有有機含氮雜環化合物哈林試驗槽 中，使槽中鐘液混合均勻吸附於試片上。電鍵時採用直流 電的方式提供。 請參閱表一，其列出本發明各實驗例中，所使用的銅 電鑛液组成。 表一：各實驗例的銅電鍍液組成 實驗例 含銅化合物 電解質 環化合物 鹵素離子 1 0.18 Μ曱酸 " 0.88 Μ 2 — CuS〇4 · 5H20 0.26 Μ乙酸 40 Ppm 20 ppm 3 0.34 Μ丙酸 201211322 第1圖是本發明實驗例1-3進行電鍍銅填孔後，基板 之剖面圖。（a)、（b)為以曱酸作為電解質（實驗例1)進 行電鍍後的基板剖面圖。（c)、（ d)則以乙酸作為電解質（實 驗例2)進行電鍍後的基板剖面圖。（e)、（f)則為以丙酸 作為電解質（實驗例3)進行電鍍後的基板剖面圖。其中， (a)、（c)、（e)以光學顯微鏡觀察的放大倍數分別為5〇 倍，而（b)、（d)、（e)之放大倍數為1〇〇倍。電鑛時間為 9小時。 由第1圖中’很明顯可以看到當以羧酸作為銅電鍍液 中的電解質時，並無夾鑛現象產生，且通孔中的銅填充效 果良好。 第2圖是本發明實驗例2進行電鍍銅填孔過程中不 同電鑛時間時基板的剖面圖。利用不同電鑛時間點的試片 切片，來觀察乙酸作為電解質時，銅沉積的效果。（a)_(c) 的電鍍時間為5小時，（d)-(f)的電錢時間為9小時，⑴ •⑴的電鑛時間為12小時。光學顯微鏡觀察的放大倍數 如下：（a)、（d)、（g)為5G倍，⑴、⑴、⑴為 倍’而（c)、（f)、（0 為 200 倍。 通冽：ί仃電鍍過㈣，通孔開口兩側的電流密度較高於 、的電流密度，因此’有機含氮雜環化合物吸附於(iii) The above-mentioned i-ion ions can help to form a coordination structure between the organic nitrogen-containing heterocyclic compound and the copper ion to stably adsorb on the copper layer, and the _-ion ion 201211322 can strengthen the organic nitrogen-containing heterocyclic compound more Adsorption on the copper layer. According to an embodiment of the invention, the halogen ion concentration is from 10 to 100 ppm. Next, the result of electroplating and filling with a different copper plating solution composition, and then observing the cross-section of the substrate and the surface of the substrate with an optical microscope (OM) will be described. The electroplating and filling steps are as follows. First, before the electroplating, the copper-containing compound, the electrolyte and the halogen ion are separately mixed uniformly, placed in a Haring cell, and the air pump is opened, and the temperature is maintained at 28 ° C using a cooling cycle machine. Leave for 30 minutes. A prepreg cup is also prepared containing an organic nitrogen-containing heterocyclic compound. The test piece used was a 4 X 6 cm 2 printed circuit board. The test piece has a through hole having a diameter of 1 μm or 150 μm, and the through hole has a depth of 230 μπι ′ so that the through hole aspect ratio is 2.3 or 1.53. Then, clean the test piece with 〇. 5 4 Μ sulfuric acid. Remove the contaminants from the surface of the plate and vortex with ultrasonic for 2 minutes to remove the residual bubbles in the through-holes of the test piece. Rinse again with ultrapure water. The test piece was placed in a Harlem test tank having an organic nitrogen-containing heterocyclic compound, and the clock liquid in the tank was uniformly mixed and adsorbed on the test piece. The keys are supplied by direct current. Please refer to Table 1, which lists the composition of the copper electro-mineral used in each of the experimental examples of the present invention. Table 1: Composition of copper electroplating solution for each experimental example Experimental example Copper-containing compound Electrolyte ring compound Halogen ion 1 0.18 Tannic acid " 0.88 Μ 2 — CuS〇4 · 5H20 0.26 Indole acetic acid 40 Ppm 20 ppm 3 0.34 Propionic acid 201211322 Fig. 1 is a cross-sectional view showing a substrate after electroplating of copper in Experimental Example 1-3 of the present invention. (a) and (b) are cross-sectional views of the substrate after electroplating using citric acid as an electrolyte (Experimental Example 1). (c) and (d) are cross-sectional views of the substrate after electroplating using acetic acid as an electrolyte (Experimental Example 2). (e) and (f) are cross-sectional views of the substrate after electroplating using propionic acid as an electrolyte (Experimental Example 3). Among them, the magnifications of (a), (c), and (e) observed by an optical microscope are 5 倍 times, and the magnifications of (b), (d), and (e) are 1 〇〇. The mine time is 9 hours. It is apparent from Fig. 1 that when a carboxylic acid is used as the electrolyte in the copper plating solution, no occurrence of entrainment occurs, and the copper filling effect in the through holes is good. Fig. 2 is a cross-sectional view showing the substrate in the case of the electrowinning time in the electroplating copper filling process of Experimental Example 2 of the present invention. The test piece slicing at different electro-mineral time points was used to observe the effect of copper deposition when acetic acid was used as the electrolyte. (a) _ (c) plating time is 5 hours, (d) - (f) electricity time is 9 hours, (1) • (1) electricity time is 12 hours. The magnifications observed by optical microscopy are as follows: (a), (d), and (g) are 5G times, (1), (1), and (1) are times ' and (c), (f), and (0 is 200 times. By: 冽仃 Electroplating (4), the current density on both sides of the opening of the through hole is higher than the current density, so the 'organic nitrogen-containing heterocyclic compound is adsorbed on
St:的濃度較高’而越往通孔中央則漠度越低。 屬會抑:第銅 作為電解質時，並不會影響有機含氮雜環物:二ί 201211322 電流密度區的能力，銅金屬同樣由通孔中央開始沉積，因 此可減少填充通孔後，所產生的空洞現象。 第3圖本發明實驗例1 -3進行電鍍銅填孔後，基板表 面照片。第3圖中’（a) - (c)依序為實驗例1 - 3之基板 表面。以幾酸作為銅電鍍液中的電解質，基板表面並無銅 瘤的產生。 由上述本發明實施方式可知，應用本發明之銅電鍍液 組成具有下列優點。第一，由於羧酸之酸性較弱，因此不 • 易與銅電鍍液中的其他成分交互作用，減少了銅電鍍沉澱 的產生。第二，可改善電鑛後的夾鍍現象，基板表面也不 會有銅瘤產生’提高印刷電路板的信賴度。第三，由於羧 酸之酸性較弱，因此可以擴大電鍍時使用無機酸的操作範 圍。 雖然本發明已以實施方式揭露如上，然其並非用以限 ，本發明，任何熟習此技藝者，在不脫離本發明之精神和 範圍内，當可作各種之更動與潤飾，因此本發明之保護範 _ 圍當視後附之申請專利範圍所界定者為準。 【圖式簡單說明】The concentration of St: is higher, and the lower the center of the through hole, the lower the indifference. The genus is: when the copper acts as an electrolyte, it does not affect the organic nitrogen-containing heterocyclic ring: 2 ί 201211322 The ability of the current density zone, the copper metal is also deposited from the center of the through-hole, thus reducing the filling after the through-hole The hollow phenomenon. Fig. 3 is a photograph of the surface of the substrate after the electroplating of copper was carried out in Experimental Example 1-3 of the present invention. In Fig. 3, '(a) - (c) are sequentially the substrate surfaces of Experimental Examples 1 - 3. With a few acids as the electrolyte in the copper plating solution, there is no copper tumor on the surface of the substrate. As is apparent from the above embodiments of the present invention, the copper plating solution composition to which the present invention is applied has the following advantages. First, because the acidity of the carboxylic acid is weak, it does not easily interact with other components in the copper plating bath, reducing the occurrence of copper plating precipitation. Second, it can improve the phenomenon of plate plating after electro-mineralization, and there is no copper tumor on the surface of the substrate. Third, since the acidity of the carboxylic acid is weak, the operating range of the inorganic acid used in electroplating can be expanded. While the present invention has been disclosed in the foregoing embodiments, the present invention is not intended to be limited thereto, and the invention may be modified and modified without departing from the spirit and scope of the invention. The scope of protection _ is defined by the scope of the patent application attached to it. [Simple description of the map]
At為讓本發明之上述和其他目的、特徵、優點與實施例 能更明顯易懂’所附圖式之說明如下： 第1圖是本發明實驗例丨_3進行電鍍銅填孔後，基板 之剖面圖。 第2圖是本發明實驗例2進行電鍍銅填孔過程中，不 同電鍍時間時基板的剖面圖。 201211322 第3圖本發明實驗例1 - 3進行電鍵銅填孔後5基板表 面照片。 【主要元件符號說明】 無The above and other objects, features, advantages and embodiments of the present invention will be more clearly understood. The description of the drawings is as follows: FIG. 1 is an experimental example of the present invention, _3, after electroplating copper is filled, the substrate Sectional view. Fig. 2 is a cross-sectional view showing the substrate in the case of performing electroplating copper filling in the experimental example 2 of the present invention at different plating times. 201211322 Fig. 3 Experimental Example 1 - 3 Photograph of the surface of 5 substrates after copper filling of the keys. [Main component symbol description] None