五、發明說明（1) ----—~ 本發明是有關於一種改善鋁銅合金電遷移阻值之方 法。 由於鋁的導電性良好，而且對氧化矽的附著力佳，故 鋁是現在超大型積體電路（VLSI)最普遍採用的導電材料。 然而’因為銘有電遷移現象（£：16(：1^01111以紂1〇11)，且妙對 鋁有一定的固態溶解度，因此在半導體工業上，便經常使 用含銅、或同時含銅與矽的鋁合金，來作為積體電路的導 體材料。此外，為了防止鋁合金層與矽的接觸界面發生尖 峰現象，並降低彼此的接觸電阻，通常在鋁合金層與矽^ 都會加入一層稱為阻障層的導體材料，例如金屬鈇；氮化 鈦以及氮化鎢。目前，常見具有較高電遷移阻值之鋁鋼合 金結構有氮化鈦/鋁銅合金/氮化鈦反反光塗佈層、 /氮化胸銅合金/氮化鈦反反光塗佈層、氣佈化曰欽/^ /鋁銅合金/氮化鈦反反光塗佈層、以及氮化鈦/鋁銅合金/ 氮化鈇反反光塗佈層等。 雖然上述的該些鋁銅合金結構可改善鋁銅合金本身的 電遷移現象，然而其電遷移阻值仍有待改睿。有鑑於習知 鋁銅合金結構之電遷移阻值不佳的現象，且已知金屬鈦為 濕潤性良好的材料，且可與鋁銅合金中的鋁進行反應，而 生成可增加鋁銅合金本身的片阻值的鋁化鈦層，故本發明 揭示一種短暫關閉氮氣供應，以在鋁銅合金表面形成一富 含金屬鈦之薄膜，其令所含的金屬鈦可在鋁銅合金沉積過 程中與合金中的鋁進行反應，而生成一鋁化鈦薄膜，進而 改善鋁銅合金的電遷移阻值。V. Description of the invention (1) -------- This invention relates to a method for improving the electromigration resistance of an aluminum-copper alloy. Because aluminum has good electrical conductivity and good adhesion to silicon oxide, aluminum is the most commonly used conductive material for very large scale integrated circuits (VLSI). However, because of the electromigration phenomenon (£: 16 (: 1 ^ 01111 to 纣 1011), and Miao has a certain solid solubility for aluminum, therefore, in the semiconductor industry, copper-containing or copper-containing is often used. Aluminum alloy with silicon is used as the conductor material of integrated circuits. In addition, in order to prevent the occurrence of spikes at the interface between the aluminum alloy layer and silicon and reduce the contact resistance between each other, a layer is usually added to the aluminum alloy layer and silicon ^ Conductive materials for the barrier layer, such as metal hafnium; titanium nitride and tungsten nitride. At present, common aluminum steel alloy structures with higher electromigration resistance values include titanium nitride / aluminum copper alloy / titanium nitride reflective coating Fabric layer, / Nitride chest copper alloy / Titanium nitride retroreflective coating layer, gas cloth, aluminum / copper alloy / titanium nitride retroreflective coating layer, and titanium nitride / aluminum copper alloy / nitrogen Chemically reflective coatings, etc. Although the above aluminum-copper alloy structures can improve the electromigration of the aluminum-copper alloy itself, its electromigration resistance still needs to be improved. In view of the conventional aluminum-copper alloy structure, Poor migration resistance, and titanium metal is known to be A material with good wettability and can react with aluminum in aluminum-copper alloy to form a titanium aluminide layer that can increase the sheet resistance of the aluminum-copper alloy itself. Therefore, the present invention discloses a method for temporarily shutting off the nitrogen supply in the aluminum-copper alloy. A titanium-rich film is formed on the surface of the alloy, which allows the contained metal titanium to react with the aluminum in the alloy during the deposition of the aluminum-copper alloy to form a titanium aluminide film, thereby improving the electromigration of the aluminum-copper alloy. Resistance value.
C:\ProgramFiIes\Patent\0503-3790-e.ptd第 4 頁 五、發明說明（2) 本發明是藉由在氮化鈦沉積前/後關閉氮氣供應，使 得氮化鈦表面含較多鈦的薄膜可與鋁銅合金中的鋁作用， 而形成一鋁化銅（TiAlg)薄膜，並進而促進鋁銅合金之電 遷移阻值。 本發明之一特徵是揭示一種改善鋁鋼合金電遷移阻值 之方法，其步驟包括：提供一基底；在一未提供氮氣的反 應室内’以氬氣轟擊金屬靶’進行反應性金屬濺鍍，形成 一金屬層於該基底上；提供氮氣供應，利用反應性離子滅 鍍法形成一第一氮化金屬層於該金屬層上；關掉氮氣供 應，並繼續進行反應性金屬錢鑛，形成一富含該金屬之第 一薄膜於該氣化金屬層上；停止反應性金屬賤鐘，沉積一 紹銅合金層於該富含該金屬之第一薄膜上，並使富含該金 屬之第一薄膜與該鋁銅合金中的鋁反應，而轉變成一第一 鋁化金屬層；在一未提供氮氣之反應室内，以氬氣轟擊金 屬靶，進行反應性金屬濺鍍，形成一富含該金屬之第二薄 膜於該紹銅合金上’同時使銘銅合金中的紹與該第二薄膜 中的金屬反應，而使該富含該金屬之第二薄膜轉變成一位 在該鋁銅合金表面之第二鋁化金屬層；以及提供氮氣供 應，利用反應性離子濺鍍法形成一第二氮化金屬層於該第 二鋁化金屬層上。如上所述之方法，其中該金屬靶為金屬 鈦；該金屬層為金屬鈦層，其厚度約為100埃；該第一氮 化金屬層係由氮化鈦所構成，其厚度約為250埃；該第一 薄膜為富含金屬鈦之薄膜；該鋁銅合金之厚度約為8〇0〇 埃；該第一鋁化金屬層係由鋁化欽所構成；該第二薄膜為C: \ ProgramFiIes \ Patent \ 0503-3790-e.ptd page 4 5. Description of the invention (2) The invention is to turn off the nitrogen supply before / after the titanium nitride deposition, so that the titanium nitride surface contains more titanium The thin film can interact with aluminum in the aluminum-copper alloy to form a copper aluminide (TiAlg) film, and further promote the electromigration resistance of the aluminum-copper alloy. One feature of the present invention is to disclose a method for improving the electromigration resistance of an aluminum-steel alloy. The steps include: providing a substrate; and performing reactive metal sputtering by bombarding a metal target with argon in a reaction chamber that does not provide nitrogen, A metal layer is formed on the substrate; a nitrogen supply is provided, and a first nitrided metal layer is formed on the metal layer by a reactive ion quenching method; the nitrogen supply is turned off, and the reactive metal money is continued to form a A first film rich in the metal is deposited on the vaporized metal layer; a reactive metal base is stopped, a copper alloy layer is deposited on the first film rich in the metal, and the first film rich in the metal is made The film reacts with the aluminum in the aluminum-copper alloy to transform into a first aluminized metal layer; in a reaction chamber that does not provide nitrogen, the metal target is bombarded with argon and reactive metal sputtering is performed to form a rich metal The second thin film on the copper-copper alloy simultaneously reacts the metal in the copper-copper alloy with the metal in the second film, so that the second film rich in the metal is transformed into an aluminum-copper alloy sheet. A second aluminide metal layer; and providing a nitrogen supply, and forming a second metal nitride layer on the second aluminide metal layer by a reactive ion sputtering method. The method as described above, wherein the metal target is metal titanium; the metal layer is a metal titanium layer with a thickness of about 100 angstroms; the first nitrided metal layer is composed of titanium nitride with a thickness of about 250 angstroms The first film is a titanium-rich film; the thickness of the aluminum-copper alloy is about 8000 angstroms; the first metal layer of aluminization is composed of aluminide; the second film is
C:\ProgramFiles\Patent\0503-3790-e.ptd第 5 頁 五、 發明說明 (3) 富 含金屬 鈦 之 薄 膜 ； 該第二鋁化 金屬 層係鋁化鈦； 該第二 氮 化金屬 層 係 由 氮 化 鈦所構成， 其厚 度約為250埃 0 本發 明 之 另 一 特 徵是揭示一 種改 善鋁銅合金電 遷移阻 值 之方法 5 其 步 驟 包 括·提供一 基底 ;在一未提供 氮氣的 反 應室内 以 氩 氣 轟 擊鈦靶，進 行反 應性金屬濺鍍 ，形成 金屬鈦 層 於 該 基 底 上；提供氮 氣供 應，利用反應 性離子 濺 鍍法形 成 第 氮 化鈦層於該 金屬 層上；關掉氮 氣供 應 ，並繼 續 進 行 反 應 性金屬濺鍍 ，形 成一富含鈦之 第一薄 膜 於該氮 化 鈦 層 上 ϊ 停止反應性 金屬 濺鍍，沉積一 鋁銅合 金 層於該 虽 含 鈦 之 第 一薄膜上， 並使 該富含鈦之第 一薄膜 與 該鋁銅 合 金 中 的 紹 反應，而轉 變成 一第一銘化鈦 層，在 —· 未提供 氮 氣 之 反 應 室内，以氬 氣轟 擊金屬靶，進 行反應 性 金屬濺鍍 5 形 成 — 富含鈦之第 二薄 膜於該鋁銅合 金上， 同 時使鋁 銅 合 金 中 的 鋁與該第二 薄膜 中的鈦反應， 而使該 富 含鈦之 第 —一 薄 膜 轉 變成一位在 該鋁 銅合金表面之 第二銘 化 鈦層； 以 及 提 供 氮 氣供應，利 用反 應性離子濺鍍 法形成 第二氮 化 鈦 層 於 該 第二鋁化鈦 層上 。如上所述之 方法， 其 中該金 屬 鈦 層 之 厚 度約為100埃；該第一氮化鈦之厚度 約 為25 0埃 ;該鋁銅合金之沉積厚度約為8〇〇〇埃；該第二 氮 化鈦之 厚 度 約 為250埃。 連 本發 明 之 另 _ _ 特 徵是揭示一 種可 ? 文善連接鎢插栓之内 線的電 遷 移 阻 值 之 方法，其步 驟包 括：提供一包 含有鶴 插 栓之半 導 體 基 底 在一未提供 氮氣 的反應室内， 以氬氣 轟 擊金屬 靶 進 行 反 應性金屬濺 鑛， 形成一連接該 鎢插栓 him C:\ProgramFiles\Patent\0503-3790_e.ptd第 6 頁 五、發明說明（4) 之金屬層於該半導體基底上；提供氮氣供應，利用反應性 離子激鍍法形成一第一氮化金屬層於該金屬層上；關掉氮 氣供應’並繼續進行反應性金屬濺鍍，形成一富含該金屬 之第一薄膜於該氮化金屬層上；停止反應性金屬濺鍍，沉 積一銘銅合金層於該富含該金屬之第一薄膜上，並使富含 該金屬之第一薄膜與該鋁銅合金中的鋁反應，而轉變成一 第一銘化金屬層；在一未提供氮氣之反應室内，以氩氣轟 擊金屬把’進行反應性金屬濺鍍，形成一富含該金屬之第 二薄膜於該鋁銅合金上，同時使鋁銅合金中的鋁與該第二 薄膜中的金屬反應，而使該富含該金屬之第二薄膜轉變成 一位在該紹銅合金表面之第二鋁化金屬層；以及提供氮氣 供應’利用反應性離子濺鍍法形成一第二氮化金屬層於該 第二銘化金屬層上。如上所述之方法，其中該金屬靶係由 金屬鈦所構成；該金屬層為金屬鈦層，其厚度約為100 埃；該第一氮化金屬層係由氮化鈦所構成，其厚度約為 250埃；該第一薄膜係富含金屬鈦之薄膜；該鋁銅合金之 厚度約為8000埃；該第一鋁化金屬層係由鋁化鈦所構成； 該第二薄膜係富含金屬鈦之薄膜；該第二鋁化金屬層係銘 化鈦，而該第二氮化金屬層係由氮化鈦所構成，其厚度約 為250埃。 本發明之另一特徵是揭示一種改善連接鎢插栓之鋁銅 内連線的電遷移阻值之方法，其步驟包括：提供—包含有 鶴插栓之半導體基底；在一未提供氮氣的反應室内，以氮 氣轟擊鈦靶，進行反應性金屬濺鍍，形成一連接該鶴插检C: \ ProgramFiles \ Patent \ 0503-3790-e.ptd page 5 5. Description of the invention (3) Metal-rich titanium film; The second metallized metal layer is titanium aluminide; the second metal nitrided layer It is composed of titanium nitride and has a thickness of about 250 angstroms. Another feature of the present invention is to disclose a method for improving the electromigration resistance of an aluminum-copper alloy. The steps include: providing a substrate; The titanium target was bombarded with argon in the room, and reactive metal sputtering was performed to form a metal titanium layer on the substrate; a nitrogen supply was provided, and a second titanium nitride layer was formed on the metal layer by a reactive ion sputtering method; the nitrogen was turned off Supply and continue reactive metal sputtering to form a first film rich in titanium on the titanium nitride layer. Stop reactive metal sputtering and deposit an aluminum-copper alloy layer on the first film containing titanium. The first thin film rich in titanium is reacted with the aluminum in the aluminum-copper alloy to transform it into a first anodized titanium layer. — · In a reaction chamber where no nitrogen is provided, the metal target is bombarded with argon and reactive metal sputtering is performed. 5 — A second film rich in titanium is formed on the aluminum-copper alloy, and the aluminum in the aluminum-copper alloy and the first The titanium in the two films reacts, so that the first titanium-rich film is transformed into a second anodized titanium layer on the surface of the aluminum-copper alloy; and a nitrogen supply is provided, and the second is formed by reactive ion sputtering. A titanium nitride layer is formed on the second titanium aluminide layer. The method described above, wherein the thickness of the metallic titanium layer is about 100 angstroms; the thickness of the first titanium nitride is about 250 angstroms; the deposited thickness of the aluminum-copper alloy is about 8000 angstroms; the second The thickness of titanium nitride is about 250 angstroms. Even another feature of the present invention is to disclose a method for connecting the electromigration resistance value of the inner wire of a tungsten plug, including the steps of: providing a semiconductor substrate including a crane plug in a reaction without supplying nitrogen gas. In the room, the metal target is bombarded with argon for reactive metal spattering to form a tungsten plug him C: \ ProgramFiles \ Patent \ 0503-3790_e.ptd Page 6 V. Description of the invention (4) The metal layer is on the On a semiconductor substrate; providing a nitrogen supply, forming a first nitrided metal layer on the metal layer using a reactive ion plating method; turning off the nitrogen supply 'and continuing the reactive metal sputtering to form a metal-rich A first thin film on the nitrided metal layer; stopping reactive metal sputtering, depositing a copper alloy layer on the first thin film rich in the metal, and allowing the first thin film rich in the metal and the aluminum copper The aluminum in the alloy reacts and turns into a first etched metal layer; in a reaction chamber that does not provide nitrogen, the metal is bombarded with argon to perform reactive metal sputtering to form a The second film containing the metal is on the aluminum-copper alloy, and at the same time, the aluminum in the aluminum-copper alloy is reacted with the metal in the second film, so that the second film rich in the metal is converted into a bit of copper in the copper. Forming a second aluminized metal layer on the surface of the alloy; and providing a nitrogen supply to form a second metal nitride layer on the second anodized metal layer using a reactive ion sputtering method. The method described above, wherein the metal target is composed of titanium metal; the metal layer is a titanium metal layer having a thickness of about 100 angstroms; the first nitrided metal layer is composed of titanium nitride and has a thickness of approximately Is 250 angstroms; the first thin film is a titanium-rich metal thin film; the thickness of the aluminum-copper alloy is about 8000 angstroms; the first aluminized metal layer is composed of titanium alumina; the second thin film is metal-rich A thin film of titanium; the second metal aluminide layer is titanium nitride, and the second metal nitride layer is composed of titanium nitride, and has a thickness of about 250 angstroms. Another feature of the present invention is to disclose a method for improving the electromigration resistance of aluminum-copper interconnects connected to tungsten plugs. The method includes the steps of: providing—a semiconductor substrate including a crane plug; In the room, a titanium target is bombarded with nitrogen, and reactive metal sputtering is performed to form a connection inspection of the crane.
C:\ProgramFiles\Patent\0503-3790-e.ptd第 7 頁 五、發明說明（5) 之金屬鈦層於該半導髏基底上；提供氮氣供應，利用反應 性離子濺鍍法形成一第一氮化鈦層於該金屬層上；關掉氮 氣供應，並繼續進行反應性金屬濺鍍，形成一富含鈦之第 一薄膜於該氮化欽層上；停止反應性金屬濺鑛，沉積一鋁 銅合金層於該富含鈦之第一薄膜上，並使該富含鈦之第一 薄膜與該鋁銅合金中的鋁反應，而轉變成一第一鋁化鈦 層；在一未提供氮氣之反應室内’以氬氣轟擊鈦乾，進行 反應性金屬濺鍍，形成一富含鈦之第二薄膜於該鋁銅合金 上，同時使鋁銅合金中的鋁與該第二薄膜中的鈇反應，而 使該富含欽之第二薄膜轉變成一位在該銘銅合金表面之第 二鋁化鈇層；以及提供氮氣供應，利用反應性離子滅鍍法 形成一第二氮化欽層於該第二銘化鈦層上。如上所述之方 法，其中該金屬鈦層之厚度約為100埃；該第一氮化鈦之 厚度約為250埃；該鋁銅合金之厚度約為8000埃；而該第 二氮化鈦之厚度約為250埃。 為使本發明之特徵以及優點更明顯可見，兹將以後續 的實施例並配合相關圖式詳細說明如下。 圖式之簡單說明： 第1A〜1C圖顯示根據本發明之一可改善電遷移阻值之 實施例。 第2A〜2E圖顯示根據本發明之另一可改善電遷移阻值 之實施例。 實施例一： 首先’請參照第1A圖，提供一半導體基底ι〇，其上並C: \ ProgramFiles \ Patent \ 0503-3790-e.ptd page 7 V. Description of the invention (5) The metal titanium layer is on the semiconductor substrate; a nitrogen supply is provided, and a reactive ion sputtering method is used to form a first layer. A titanium nitride layer is on the metal layer; the nitrogen supply is turned off, and reactive metal sputtering is continued to form a first film rich in titanium on the nitride layer; stop the reactive metal sputtering and deposit An aluminum-copper alloy layer on the titanium-rich first film, and the titanium-rich first film reacts with aluminum in the aluminum-copper alloy to transform into a first titanium aluminide layer; The reaction chamber of nitrogen was bombarded with titanium by argon, and reactive metal sputtering was performed to form a second film rich in titanium on the aluminum-copper alloy. At the same time, the aluminum in the aluminum-copper alloy and the aluminum in the second film were formed. Thallium reaction, so that the second Qin-rich film is converted into a second Titanium aluminide layer on the surface of the Ming copper alloy; and a nitrogen supply is provided to form a second Nitride layer by reactive ion quenching. On the second titanium layer. The method as described above, wherein the thickness of the metal titanium layer is about 100 angstroms; the thickness of the first titanium nitride is about 250 angstroms; the thickness of the aluminum-copper alloy is about 8000 angstroms; The thickness is about 250 Angstroms. In order to make the features and advantages of the present invention more obvious, the following embodiments and the related drawings are described in detail below. Brief description of the drawings: Figures 1A to 1C show an embodiment in which the electromigration resistance can be improved according to one of the present invention. Figures 2A to 2E show another embodiment which can improve the resistance of electromigration according to the present invention. First Embodiment: First, please refer to FIG. 1A, a semiconductor substrate ι0 is provided, and
C:\ProgramFiles\Patent\0503-3790-e.ptd第 8 頁 五、發明說明（6) 可形成有半導體元件。其次，在一關閉氮氣供應開關但含 有氬氣供應的反應室内，以鈇金屬作為氬氣轟擊的靶，進 行反應性金屬濺鍍’形成一厚度約1〇〇埃之金屬鈦層12於 基底1 0上。然後’打開氮氣供應開關，使該反應室内充滿 氮氣以及氬氣，並繼續進行反應性濺鍍反應，以鈦金屬作 為氮氣以及氬氣轟擊的靶，形成一厚度約250埃之氮化鈦 層14於金屬鈦層12上。接著，關閉氮氣供應開關，並進續 進行反應性離子濺鍍反應，形成一厚度約埃且富含金 屬鈦的薄膜16於氮化鈦層14上。 接著，請參照第1B圖，在富含金屬鈦的薄膜16形成 後’沉積一厚度約8000埃之鋁銅合金層20於該富含金屬鈦 之薄膜16上’並使該富含金屬鈦之薄膜16與鋁銅合金層2〇 中的鋁反應，而轉變成鋁化鈇層18。 最後’請參照第1C圖，同樣於一關閉氮氣供應開關但 含有氬氣供應的反應室内進行反應性離子濺鑛，形成一厚 度約100埃且富含金屬鈦之薄膜於鋁銅合金層2〇上（未顯 示）’同時使鋁銅合金中的鋁與薄膜中的金屬鈦反應，而 使該富含金屬鈦之薄膜轉變成一位在該鋁銅合金表面之銘 化鈦層22。接著，於同一反應室内’打開氮氣供應開關， 使該反應室内充滿氮氣以及氬氣’繼續進行反應性離子機 鍍反應，以金屬鈦作為氮氣以及氬氣轟擊的把，形成—厚 度約250埃之氮化鈦層24於鋁化鈦層22上，作為反反光塗 佈層（anti-reflection coating layer ;ARC)。 根據本發明之實施例’藉由在連接基底1〇上之半導體C: \ ProgramFiles \ Patent \ 0503-3790-e.ptd page 8 5. Description of the invention (6) Semiconductor elements can be formed. Secondly, in a reaction chamber with the nitrogen supply switch turned off but containing argon supply, reactive metal sputtering was performed using thallium metal as a target for argon bombardment to form a metallic titanium layer 12 having a thickness of about 100 angstroms on the substrate 1 0 on. Then, the nitrogen supply switch was turned on, the reaction chamber was filled with nitrogen and argon, and the reactive sputtering reaction was continued. Titanium metal was used as a target bombed by nitrogen and argon to form a titanium nitride layer with a thickness of about 250 angstroms. 14 On the metal titanium layer 12. Next, the nitrogen supply switch is turned off, and a reactive ion sputtering reaction is continued to form a thin film 16 having a thickness of about Angstroms and rich in titanium on the titanium nitride layer 14. Next, referring to FIG. 1B, after the metal-titanium-rich film 16 is formed, an aluminum-copper alloy layer 20 having a thickness of about 8000 angstroms is deposited on the metal-titanium-rich film 16 and the metal-titanium-rich film 16 is deposited. The thin film 16 reacts with aluminum in the aluminum-copper alloy layer 20 to be converted into a hafnium alumina layer 18. Finally, please refer to FIG. 1C. Reactive ion sputtering is also performed in a reaction chamber with the nitrogen supply switch turned off but containing argon gas supply to form a film with a thickness of about 100 angstroms and rich in metal titanium on the aluminum-copper alloy layer. The above (not shown) 'simultaneously reacts the aluminum in the aluminum-copper alloy with the metal titanium in the film, so that the metal-titanium-rich film is transformed into an inscribed titanium layer 22 on the surface of the aluminum-copper alloy. Next, in the same reaction chamber, 'turn on the nitrogen supply switch and fill the reaction chamber with nitrogen and argon' to continue the reactive ion plating reaction. Titanium metal is used as the nitrogen and argon bombarded to form a thickness of about 250 angstroms. The titanium nitride layer 24 is formed on the titanium aluminide layer 22 as an anti-reflection coating layer (ARC). According to an embodiment of the present invention ', by using a semiconductor on a connection substrate 10
五 元件用^銅合金内連線之上、τ表面各生成—銘化欽 層，改善鋁鋼合金之電遷移阻值。 實施例二： 首先，f參照第2Α圖，提供一半導體基底2〇，其上並 形成有一預定乍為插栓用的接觸開口 22。接著，依序形成 一由金屬鈦/氮化鈦所構成之阻障層24覆蓋半導體基底2〇 以及接觸開口 22之内壁以及底部。然後，再以習知的金屬 製程形成一金屬鎢層26於阻障層24上。 其次，請參照第2B圖，利用鎢回蝕刻製程回蝕刻半導 體基底20表面多餘的金屬鎢層26以及阻障層24，於接觸開 口 22内形成一鎢插栓28。 接著、，請參照第2C圖，在一未提供氮氣但充滿氬氣的 反應室内以鈦金屬作為氬氣轟擊的靶，進行反應性金屬濺 鍍，形成一連接鎢插栓2 8且厚度約1〇〇埃之金屬鈦層3〇於 基底20上。然後，打開氮氣供應開關，使該反應室内充滿 氮，三並繼續進行反應性濺鍍反應’以金屬鈦作為氮氣以 及氬氣轟擊的靶，形成一厚度約250埃之氮化鈦層32於金 屬鈦層3 0上。接著’關閉氮氣供應開關，並進續進行反應 性離子藏鍍反應’形成一厚度約100埃且富含金屬鈦的薄 膜34於氮化鈦層32上。 接著’請參照第2D圖’在富含金屬鈦的薄膜34形成 後，沉積一厚度約8000埃之鋁銅合金層38於該富含金屬鈦 之薄膜34上’並使該富含金屬鈦之薄膜34與鋁銅合金層38 中的鋁反應’而轉變成鋁化鈦層36。Five components ^ copper alloy interconnects on the surface of the τ-Ming Huaqin layer to improve the electromigration resistance of aluminum steel alloy. Second Embodiment: First, referring to FIG. 2A, a semiconductor substrate 20 is provided, and a contact opening 22 is formed thereon for a plug. Next, a barrier layer 24 made of metal titanium / titanium nitride is sequentially formed to cover the semiconductor substrate 20 and the inner wall and the bottom of the contact opening 22. Then, a metal tungsten layer 26 is formed on the barrier layer 24 by a conventional metal process. Next, referring to FIG. 2B, a tungsten etch-back process is used to etch back the excess metal tungsten layer 26 and the barrier layer 24 on the surface of the semiconductor substrate 20 to form a tungsten plug 28 in the contact opening 22. Next, referring to FIG. 2C, reactive metal sputtering is performed with titanium metal as a target of argon bombardment in a reaction chamber that is not provided with nitrogen but is filled with argon, and a tungsten plug 28 is formed with a thickness of about 1 A 00 titanium metal layer 30 is on the substrate 20. Then, turn on the nitrogen supply switch to fill the reaction chamber with nitrogen, and continue the reactive sputtering reaction. "Titanium metal is used as the target of nitrogen and argon bombardment to form a titanium nitride layer 32 with a thickness of about 250 angstroms on the metal. Titanium layer on 30. Next, "the nitrogen supply switch is turned off, and the reactive ion storage plating reaction is continued" to form a thin film 34 having a thickness of about 100 angstroms and rich in titanium metal on the titanium nitride layer 32. Next, "please refer to Fig. 2D" after the metal-titanium-rich film 34 is formed, an aluminum-copper alloy layer 38 having a thickness of about 8000 angstroms is deposited on the metal-titanium-rich film 34 and the metal-titanium-rich film 34 is formed. The thin film 34 reacts with aluminum in the aluminum-copper alloy layer 38 to be converted into a titanium aluminide layer 36.
C:\ProgramFiles\Patent\0503-3790-e.ptd第 10 頁 五、發明說明（8) 最後’請參照第2E圖，同樣於一未提供氮氣但提供氬 氣的反應室内進行反應性離子濺鍍，形成一厚度約1 〇〇埃 且富含金屬鈦之薄膜（未顯示）於鋁銅合金層38上，同時使 紹鋼合金層38中的鋁與薄膜中的金屬鈦反應，而使富含金 屬鈦之薄膜轉變成一位在該鋁銅合金層38表面之鋁化鈦層 4 〇 °接著’於同一反應室内打開氮氣供應開關，使該反應 室内充滿氮氣以及氬氣’繼續進行反應性離子濺鍍反應， 以金屬鈦作為氮氣以及氬氣轟擊的數，形成一厚度約250 埃之氮化鈦42於鋁化鈦層40上，作為反反光塗佈層 (anti-reflection coating layer ； ARC) ° 根據本發明之實施例，藉由在連接鎢插栓2 4用的鋁銅 合金内連線上、下表面各生成一鋁化鈦層，改善鋁銅合金 之電遷移阻值。 如上所述，根據本發明所揭示之方法，藉由關閉反應 至内的氮氣供應而生成一富含金屬鈦之薄膜，使其可與銘 銅合金層中的鋁反應，進而生成一可增加電遷移阻值之铭 化鈦層。 雖然本發明已以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 和範圍内，所作之各種更動與潤飾’均落在本發明的專利 範圍内。此外，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。C: \ ProgramFiles \ Patent \ 0503-3790-e.ptd Page 10 V. Description of the invention (8) Finally, please refer to Figure 2E. Reactive ion sputtering is also performed in a reaction chamber that does not provide nitrogen but provides argon. Plating to form a thin film (not shown) with a thickness of about 100 angstroms and rich in metal titanium on the aluminum-copper alloy layer 38, and at the same time, the aluminum in the alloy steel layer 38 of Shao steel reacts with the metal titanium in the film to make The titanium-containing film is transformed into a titanium aluminide layer 40 ° on the surface of the aluminum-copper alloy layer 38. Then, the nitrogen supply switch is turned on in the same reaction chamber, so that the reaction chamber is filled with nitrogen and argon gas to continue the reactive ions. The sputtering reaction uses titanium metal as the nitrogen and argon bombarded number to form a titanium nitride 42 with a thickness of about 250 angstroms on the titanium aluminide layer 40 as an anti-reflection coating layer (ARC). ° According to the embodiment of the present invention, a titanium aluminide layer is formed on each of the upper and lower surfaces of the aluminum-copper alloy interconnecting wire for connecting the tungsten plug 24 to improve the electromigration resistance of the aluminum-copper alloy. As described above, according to the method disclosed in the present invention, a metal-titanium-rich film is formed by shutting off the nitrogen supply to the inside of the reaction, so that it can react with aluminum in the copper alloy layer, thereby generating an electricity that can increase electricity. Anodized titanium layer of migration resistance. Although the present invention has been disclosed as above with preferred embodiments, 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. Range of patents. In addition, the scope of protection of the present invention shall be determined by the scope of the appended patent application.
C:\ProgramFiles\Patent\0503-3790-e.ptd 第 11 頁C: \ ProgramFiles \ Patent \ 0503-3790-e.ptd page 11