4 3 1: b 3 5578twf.doc/006 A7 B7 經濟部中央標準局員工消費合作社印装 五、發明説明(/) 本發明是有關於一種積體電路的半導體結構,且特別 是有關於一種應用在積體電路之銅保險絲(fuse)的結 構。 在半導體製程的設計規則(design rule)邁入0.18μπι 或以下的尺寸之際,爲了克服RC延遲(RC del ay)的問題, 在金屬化的製程部份已逐漸有利用電阻較小的銅金屬來 取代其他金屬,以作爲半導體製程金屬化材料的趨勢。然 而,由於銅極易與空氣中的氧氣反應,而在銅表面形成一 薄氧化物層,造成電性接觸上的問題,使得在現今的設計 規則下,銅材質難以如同鋁金屬般應用在保險絲的設計 上。 有鑑於此,本發明就是在提供一種應用在積體電路製 程之銅保險絲的結構,以降低RC延遲。 因此,本發明提供一種積體電路銅保險絲結構,包括 二銅金屬銲墊,形成在一半導體基底上,銅金屬銲墊之間 以一介電材料隔開;利用形成在半導體基底上之一金屬 線,使其一端電性連接二銅金屬銲墊之一,而其另一端則 與二銅金屬銲墊之另一電性連接;以及形成在半導體基底 上之一保護層,覆蓋二銅金屬銲墊。 本發明再提供一種積體電路銅保險絲之製造方法,係 在一基底上形成二銅金屬銲墊,其中銅金屬銲墊之間電性 絕緣。之後,在銅金屬銲墊上形成一保護層,保護層具有 一開口而使銅金屬銲墊暴露出。續在銅金屬銲墊上形成一 包括以鋁製成之金屬線,覆蓋銅金屬銲墊且將銅金屬銲墊 3 (請先閱讀背面之注意事項r 寫本頁) -5 本紙張尺度遑用中國國家橾準(CMS >八4规格(210Χ297公釐) A7 B7 5 578twf.doc/006 五、發明説明d) 電性連接。 爲讓本發明之上述和其他目的、特徵、和優點能更明 顯易懂’下文特舉一較佳實施例,並配合所附圖式,作詳 細說明如下: 圖式之簡單說明: 第1圖係通根據本發明一較佳實施例,銅保線絲結 構之剖面圖;以及 第2圖係爲第1圖本發明較佳實施例之俯視圖,其中 I-Ι切面之剖面結構如第1圖所示。 其中,各圖標號之簡單說明如下: 100a :元件區 100b :周邊電路區 102 :介電材料 104a、104b :保護層 1 06a、106b :銅金屬銲墊 l〇8a、108b :阻障層 110a、〗10b :金屬層 112 :開口 實施例 請參照第1圖,積體電路結構的元件區l〇〇a,在完成 金氧半電晶體元件與接觸窗(未繪出)之後,繼續係形成鎢 插塞。之後,則進行導線與介層窗等金屬化製程,例如以 嵌金法(damascene)方式形成,其中導線與介層窗之間以 介電材料102相隔。緊接著,進行保護層 4 本紙張尺度逋用中國國家標準(CNS ) A4規格(2丨0X297公楚) ----------0------tj------0 (請先聞讀背面之注意事項一' /寫本頁) 經濟部中央梯率局負工消f合作社印裂 A7 B7 5578twf.doc/006 五、發明説明(3) (請先閱讀背面之注意事項再填寫本頁) (pasS1vatlon)H)4a的沉積’並定義保護層1〇4a而形成銲 墊窗口(pad window),暴露出一金屬銲墊i〇6a,例如以銅 製成ΰ之後’再形成一阻障層(barrier layer)108a,例 如爲ΤιΝ或TaN等’並在阻障層l〇8a上形成一金屬鋁 ll〇a ’並定義鋁金屬,而完成積體電路元件區1Q0後段之 打導線(wire bonding)製程。 經濟部中央樣準局貞工消費合作社印裝 再請同時參照第1圖與第2圖,建立在周邊電路區 (peripheral region)102b的銅保險絲,同樣在介電材料 102中與元件區i〇〇a相同,利用例如爲嵌金法形成二銅金 屬銲墊106b,銅金屬銲墊106b係分別連接至其對應的元 件(未繪出),而其之間係有介電材料隔離。之後.,在元件 區100a形成保護層104a的同時,亦同時形成保護層l〇4b 覆蓋在銅金屬銲墊l〇6b上,保護層104b例如爲二氧化矽 /氮化矽層。接著,在元件區102a定義保護層104a的同 時,利用微影蝕刻技術在保護層104b形成開口 112,以暴 露出二銅金屬銲墊106b。續在銅金屬銲墊106b上形成阻 障層108b,例如以金屬濺鍍形成ΤιΝ或TaN等。續在阻障 層108b上形成金屬層ll〇b,例如以金屬濺鍍形成鋁,覆 蓋銅金屬銲墊l〇6b,而將二銅金屬銲墊106b電性連接, 其中阻障層l〇8b係用以增加銅金屬銲墊106b與金屬層 110b之間的附著力。之後,再進行定義金屬層ll〇b與阻 障層108的步驟,而形成例如爲第2圖所示多條平行排列 的保險絲UOb,其中金屬層U〇b的一端與銅金屬銲墊 106b之一連接,另一端則與銅金屬銲墊l〇6b之另一連接。 5 本紙張尺度逍用中國國家標牟(CNS > A4规格(210X297公釐) 經濟部中央標準局員工消费合作社印製 14392 b ο A7 5578twf.doc/Q06 B7 五、發明説明(4) 二銅金屬銲墊106b與金屬線110b係爲本發明較佳實 施例之銅保險絲結構,銅金屬銲墊106b間係電性絕緣, 而以金屬線110b電性連接。因此當欲切斷第2圖示中任 一條保險絲時,則利甩雷射的方式將其中的金屬線110b 部分燒斷即可,而不會損害到銅金屬銲墊106b的部分。 在本發明較佳實施例的銅金屬銲墊106b,因其上覆蓋 有保護層104b與金屬層110b,使銅金屬銲墊106b與空氣 隔絕,因此在製程完成後,銅金屬銲墊106b不會暴露出, 故可避免銅與空氣接觸而造成銅表面氧化的反應。而利用 銅金屬銲墊106b作爲保險絲的一部份,可降低RC延遲。 另外,形成本發明較佳實施例銅保險絲結構的製程步 驟,與積體電路結構元件區100a之後段製程相容,因此 在製造上不會增加成本。 本發明較佳實施例之保險絲結構,係利用一鋁金屬線 覆蓋且電性連接二銅金屬銲墊,除了利用銅金屬銲墊作爲 保險絲之一部份降低RC延遲之外,而將鋁金屬線燒斷即 可切斷保險絲。另外,在銅金屬銲墊上覆蓋鋁金屬線與保 護層,更可隔絕空氣防止銅金屬銲墊氧化。 雖然本發明已以一較佳實施例揭露如上,然其並非用 以限定本發明,任何熟習此技藝者,在不脫離本發明之精 神和範圍內,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爲準。 裝 訂 線 (請先聞讀背面之注意事項再填寫本頁) 6 本紙張尺度適用中國國家梂準(CNS > A4規格(210X297公釐)4 3 1: b 3 5578twf.doc / 006 A7 B7 Printed by the Consumer Cooperative of the Central Bureau of Standards of the Ministry of Economic Affairs 5. Description of the invention (/) The present invention relates to a semiconductor structure of an integrated circuit, and in particular to an application Structure of copper fuse in integrated circuit. As the design rule of semiconductor processes moves to a size of 0.18 μm or less, in order to overcome the RC delay problem, copper metal with lower resistance has gradually been used in the metallization process part. To replace other metals as a trend for metallization materials in semiconductor processes. However, because copper easily reacts with oxygen in the air, a thin oxide layer is formed on the copper surface, causing electrical contact problems. Under the current design rules, copper is difficult to be used in fuses like aluminum. Design. In view of this, the present invention is to provide a structure of a copper fuse applied to an integrated circuit process to reduce RC delay. Therefore, the present invention provides an integrated circuit copper fuse structure including two copper metal pads formed on a semiconductor substrate, and the copper metal pads are separated by a dielectric material; using a metal formed on the semiconductor substrate Wire, one end of which is electrically connected to one of the two copper metal pads, and the other end of which is electrically connected to the other of the two copper metal pads; and a protective layer formed on the semiconductor substrate, covering the two copper metal pads pad. The invention further provides a method for manufacturing an integrated circuit copper fuse, which comprises forming two copper metal pads on a substrate, wherein the copper metal pads are electrically insulated. After that, a protective layer is formed on the copper metal pad, and the protective layer has an opening to expose the copper metal pad. Continue to form a metal wire made of aluminum on the copper metal pad, covering the copper metal pad and placing the copper metal pad 3 (Please read the precautions on the back first to write this page) -5 This paper uses China National standard (CMS > 8 4 specifications (210 × 297 mm) A7 B7 5 578twf.doc / 006 5. Description of the invention d) Electrical connection. In order to make the above and other objects, features, and advantages of the present invention more comprehensible, a preferred embodiment is exemplified below, and in conjunction with the accompanying drawings, the detailed description is as follows: Brief description of the drawings: FIG. 1 FIG. 2 is a cross-sectional view of a copper wire structure according to a preferred embodiment of the present invention; and FIG. 2 is a top view of the preferred embodiment of the present invention in FIG. 1, where the cross-sectional structure of the I-I cut plane is as shown in FIG. 1. Show. Among them, a brief description of each icon number is as follows: 100a: element area 100b: peripheral circuit area 102: dielectric material 104a, 104b: protective layer 106a, 106b: copper metal pad 108a, 108b: barrier layer 110a, 〖10b: Metal layer 112: Refer to Figure 1 for an example of the opening. The element area 100a of the integrated circuit structure, after completing the metal-oxide-semiconductor element and the contact window (not shown), continues to form tungsten. Plug. After that, metallization processes such as wires and interlayer windows are performed, for example, by a damascene method, in which the wires and the interlayer windows are separated by a dielectric material 102. Immediately after that, the protective layer 4 was used. The paper size was in accordance with Chinese National Standard (CNS) A4 (2 丨 0X297). ---------- 0 ------ tj ----- -0 (Please read the precautions on the back first '/ write this page) The Central Ramp Bureau of the Ministry of Economic Affairs, Consumer Cooperatives, F Cooperatives, Printing A7 B7 5578twf.doc / 006 5. Invention Description (3) (Please read the back first Please pay attention to this page and then fill in this page) (pasS1vatlon) H) Deposition of 4a 'and define the protective layer 104a to form a pad window, exposing a metal pad i06a, for example, made of copper 'An additional barrier layer 108a is formed, for example, TiN or TaN', and a metal aluminum 110a is formed on the barrier layer 108a, and an aluminum metal is defined to complete the integrated circuit element region 1Q0. The subsequent wire bonding process. Printed by Zhengong Consumer Cooperative of the Central Sample Bureau of the Ministry of Economics. Please refer to Figure 1 and Figure 2 at the same time. The copper fuse built in the peripheral region 102b is also in the dielectric material 102 and the component area i. 〇a is the same. For example, the two copper metal pads 106b are formed by a gold inlay method. The copper metal pads 106b are respectively connected to corresponding components (not shown), and a dielectric material is used to isolate them. After that, when the protective layer 104a is formed in the device region 100a, a protective layer 104b is also formed to cover the copper metal pad 106b. The protective layer 104b is, for example, a silicon dioxide / silicon nitride layer. Next, while the protective layer 104a is defined in the element region 102a, an opening 112 is formed in the protective layer 104b by using a photolithographic etching technique to expose the two copper metal pads 106b. The barrier layer 108b is formed on the copper metal pad 106b, for example, Tn or TaN is formed by metal sputtering. Continue to form a metal layer 110b on the barrier layer 108b. For example, aluminum is formed by metal sputtering to cover the copper metal pad 106b, and the two copper metal pads 106b are electrically connected, wherein the barrier layer 108b It is used to increase the adhesion between the copper metal pads 106b and the metal layer 110b. After that, the steps of defining the metal layer 110b and the barrier layer 108 are performed to form, for example, a plurality of fuses UOb arranged in parallel as shown in FIG. 2, where one end of the metal layer U0b and the copper metal pad 106b One connection, the other end is connected to the other of the copper metal pad 106b. 5 This paper size is in accordance with China's national standard (CNS > A4 size (210X297mm) Printed by the Consumer Cooperative of the Central Standards Bureau of the Ministry of Economic Affairs 14392 b ο A7 5578twf.doc / Q06 B7 V. Description of the invention (4) Bronze The metal pads 106b and the metal wires 110b are copper fuse structures of the preferred embodiment of the present invention. The copper metal pads 106b are electrically insulated, and are electrically connected by the metal wires 110b. Therefore, when the second diagram is to be cut off When any one of the fuses is used, the metal wire 110b may be partially blown by means of a laser beam without damaging the copper metal pad 106b. The copper metal pad in the preferred embodiment of the present invention 106b, because it is covered with a protective layer 104b and a metal layer 110b, so that the copper metal pad 106b is isolated from the air, so after the process is completed, the copper metal pad 106b will not be exposed, so the contact between copper and air can be avoided The oxidation reaction of the copper surface. The use of copper metal pads 106b as part of the fuse can reduce the RC delay. In addition, the process steps of forming the copper fuse structure of the preferred embodiment of the present invention and the integrated circuit structure element area 100a The subsequent processes are compatible, so there is no cost increase in manufacturing. The fuse structure of the preferred embodiment of the present invention uses an aluminum metal wire to cover and electrically connect two copper metal pads, except that copper metal pads are used as fuses. In addition to reducing the RC delay, the aluminum metal wire can be blown to cut off the fuse. In addition, covering the aluminum metal wire and the protective layer on the copper metal pad can isolate the air and prevent the copper metal pad from oxidizing. Although The present invention has been disclosed as above with a preferred embodiment, but it is not intended to limit the present invention. Any person skilled in the art can make various modifications and retouches without departing from the spirit and scope of the present invention. Therefore, the present invention The scope of protection shall be subject to the definition of the scope of the attached patent application. Gutter (please read the precautions on the back before filling this page) 6 This paper size is applicable to China National Standards (CNS > A4 Specification (210X297 Mm)