A7 B7 經濟部智慧財產局員工消費合作社印製 451406 5888twf.doc/008 五、發明説明（f ) 本發明是有關於一種半導體元件的製造方法，且特別 是有關於一種金屬鑲嵌的製造方法。 當積體電路之積集度日趨增加，爲了配合金氧半導體 電晶體(MOS)縮小後’所需增加的內連線需求，多重金屬 化製程便逐漸成爲許多積體電路元件所採用的方式。通 常，MOS.電晶體各極與金屬層之間，係以介電層加以隔離， 並藉由接觸窗插塞連接；而各個金屬層之間，亦使用介電 層隔離，並以介層窗插塞（via plug)進行連接。 對半導體元件後段（backend)製程而言，隨著金屬 線寬(width of metal line)的日趨縮小，金屬線所承受之電 流密度（current density)，相對地逐漸增大，使得傳統以銘 金屬爲主所形成之金屬線’遭受到電致遷移（electron migration，EM)效應的影響，進而導致元件之可靠度 (reliability)降低。 爲解決導體元件進入深次微米製程時所遭遇之 課題，使用效應極小之銅金屬，就成了所有半導體 元件製造者一、#钱選擇。但是當銅金屬作爲金屬接觸窗插 塞而與源極/¾¾'極#接觸時，會產生接面漏電（junction leakage)現象。以鎢作爲金屬接觸窗插塞時，則不會產 生接面漏電現象，加上以化學氣相沉積法所沉積的鎢的內 應力並不高(約在l〇E9dyne/cm2以下）’且具備極佳的階梯 覆蓋能力（step coverage)，因此以化學氣相沉積法來沉積 作爲接觸窗用途的金屬鎢，已成爲半導體上的標準製程之 3 (請先閲讀背面之注意事項再填寫本頁)A7 B7 Printed by the Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs 451406 5888twf.doc / 008 V. Description of the Invention (f) The present invention relates to a method for manufacturing a semiconductor element, and more particularly to a method for manufacturing a metal inlay. As the integration degree of integrated circuits is increasing, in order to meet the increased interconnect requirements required after the reduction of MOS transistors, multiple metallization processes have gradually become the method adopted by many integrated circuit components. In general, the MOS transistor's electrodes are separated from the metal layer by a dielectric layer and connected by contact window plugs. The metal layers are also separated by a dielectric layer and separated by a dielectric window. Connect via plug. For the backend process of semiconductor devices, as the width of metal line is shrinking, the current density that the metal line is exposed to has gradually increased, making traditionally using metal as the The metal wire formed by the host suffers from the effect of electromigration (EM) effect, which leads to a decrease in the reliability of the device. In order to solve the problems encountered when conductor components enter the deep sub-micron process, the use of copper metal with very small effects has become a choice for all semiconductor device manufacturers. However, when copper metal is used as a metal contact window plug and comes into contact with the source electrode, the junction leakage phenomenon will occur. When tungsten is used as the metal contact window plug, there is no leakage at the interface, and the internal stress of tungsten deposited by chemical vapor deposition is not high (about 10E9dyne / cm2 or less) and it has Excellent step coverage, so chemical vapor deposition of metal tungsten for contact window applications has become a standard process on semiconductors (Please read the precautions on the back before filling this page)
本紙張尺度適用中國國家標準（CNS > A4规格（210X297公釐） A7 B7 451406 5888twf.doc/008 五、發明説明（7 ) 請參照第1A圖至第1E圖，其繪示爲習知金屬鑲嵌之 製造流程剖面圖。首先，請參照第1A圖，於具有源極々及 極102之基底100上形成一介電層1〇4，接著，在此介電 層104上，以電獎化學氣相沉積法或低壓化學氣相沉積法 .形成一層氮化砂層106 ’其功能在於可作爲蝕刻的終止層。 接著，請參照第1B圖，在氮化砂層1〇6上旋塗一層 光阻材料，經由微影形成光阻圖案，再進行非等向性蝕刻， 形成一接觸窗開口 110，並曝露出源極/汲極區。 接著，請參照第1C圖，以低壓化學氣相沉積法沉積 金屬鎢層於氮化砍層106上，並塡滿接觸窗開口 no內。 再進行金屬鎢層的化學機械硏磨，將高於氮化矽層106上 的金屬鎢層加以去除，只餘留接觸窗闆口 110內之金屬鎢 108 ° 接著，請參考第1D圖，形成一層氧化矽層122於氮 化矽106上。接著進行微影蝕刻製程，於氧化矽層122中 彤成配線溝渠124，而於此配線溝渠124之定義過程中， 此氮化矽層106係做爲蝕刻終止層。 接著，請參考第1E圖’以濺鍍方式形成一層金屬銅 層120於配線溝渠124中，並與位在接觸窗開口 110內的 金屬鎢108電性連接，並去除氧化矽層122表面之金屬層， 使剩餘之金屬層只存留於配線溝渠124中’如此即完成了 金屬鑲嵌的製程。 上述習知金屬鑲嵌製程中之接觸窗插塞的製造方法’ 雖然可避免接面漏電現象的發生’但當半導體技術降至 4 本紙張尺度適用中國國家標準（CNS ) Α4規格（210X297公着） (請先閲讀背面之注意事項再填寫本頁) 7衣·This paper size applies to Chinese national standards (CNS > A4 size (210X297 mm) A7 B7 451406 5888twf.doc / 008 V. Description of the invention (7) Please refer to Figures 1A to 1E, which are shown as conventional metals A cross-sectional view of the manufacturing process of the damascene. First, referring to FIG. 1A, a dielectric layer 104 is formed on a substrate 100 having a source electrode 々 and a electrode 102, and then, on this dielectric layer 104, a chemical gas is awarded by electricity. Phase deposition method or low-pressure chemical vapor deposition method. A layer of nitrided sand layer 106 is formed, which functions as a stop layer for etching. Next, referring to FIG. 1B, a layer of photoresist is spin-coated on the nitrided sand layer 106. Then, a photoresist pattern is formed by lithography, and then anisotropic etching is performed to form a contact window opening 110, and the source / drain region is exposed. Next, refer to FIG. 1C, and deposit by a low pressure chemical vapor deposition method. The metal tungsten layer is on the nitride cutting layer 106 and fills the contact window opening no. Then, the chemical mechanical honing of the metal tungsten layer is performed to remove the metal tungsten layer above the silicon nitride layer 106, leaving only the remaining Contact the tungsten metal in the window panel opening 110 ° Referring to FIG. 1D, a silicon oxide layer 122 is formed on the silicon nitride 106. Then, a lithographic etching process is performed to form a wiring trench 124 in the silicon oxide layer 122. During the definition of the wiring trench 124, the nitrogen The siliconized layer 106 is used as an etching stopper. Next, please refer to FIG. 1E 'a metal copper layer 120 is formed in the wiring trench 124 by sputtering, and is electrically connected to the metal tungsten 108 in the contact window opening 110. Connect and remove the metal layer on the surface of the silicon oxide layer 122 so that the remaining metal layer is left only in the wiring trench 124. 'This completes the metal damascene process. The manufacturing method of the contact window plug in the conventional metal damascene process described above 'Although the leakage of junctions can be avoided', when the semiconductor technology is reduced to 4 paper standards, the Chinese National Standard (CNS) A4 specification (210X297) (please read the precautions on the back before filling this page) 7 ·
,1T 經濟部智慧財產局員工消費合作社印製 4514 Ο u 5888twf.doc/008_B7 _ 五、發明説明（》）, 1T Printed by the Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs 4514 Ο u 5888twf.doc / 008_B7 _ V. Description of the invention (")
0.18微米或甚至更小的世代時，接觸窗面積的縮小所引發 接觸電阻變大的情形，成爲半導體工程上亟待克服的問 題。而接觸窗結構的接觸電阻大小，取決於接觸面積，而 當接觸面積越大時’則接觸電阻的阻値通常也越小D 因此’本發明提供一種金屬鑲嵌製程中之接觸窗插塞 的製造方法，以製作出低接觸電阻的接觸窗結構。但在製 作此接觸窗結構過程中，利用微影蝕刻技術，在氧化層中 形成配線溝渠時，接觸窗插塞之側壁角落有微溝 (microtrench)現象的產生。因而本發明利用化學氣相沉積 法，於接觸窗插塞之凸出部份的側壁形成間隙壁，避免了 微溝的問題。. 一: 根據本發明之上述及其他目的，提出一種金屬鑲嵌的 製造方法。首先提供一基底，此基底上已形成有源/汲極 區，然後於基底上形成一層內層介電材料，並依化學機械 硏磨法來平坦化內層介電材料，再於內層介電層上形成一 層終止層。之後，於終止層上形成一層第一氧化層，再進 行微影蝕刻製程，以彤成接觸窗開口於第一氧化層、終止 層與介電層中，並曝露出源極/汲極。之後，於第一氧化 層上沉積一層導電材料，以塡滿接觸窗開口，再去除位於 弟氧化層上之導材料’以形成接觸窗插塞。然後於第 —氧化層上沉積一層第二氧化層，再進行微影蝕刻製程， 以形成配線溝渠於第一氧化層與第二氧化層中，並以終止 層爲蝕刻終止層’使得接觸窗插塞突出於終止層表面。接 著’依化學氣相沉積法’於終止層上沉積—層黏著層（glue 5 本紙張尺度適用中國國家標準（CNS ) A4規格（2i〇x297公楚） ------------ (請先閲讀背面之注意事項再填寫本頁) 訂 經濟部智慧財產局員工消費合作社印裂 A7 B7 4 514 0 6 5888twf.doc/008 .i、發明説明（γ ) layer)，再依化學氣相沉積法，於黏著層上一層沉積導電 層，並覆蓋住接觸窗插塞之突出之部份，然後進行回触刻 步驟，以形成間隙壁於接觸窗插塞之突出部份的側壁β胃 於黏著層上與接觸窗插塞上沉積一層擴散障礙層（diffUsi〇n barrier layer)，接著，於擴散障礙層上沉積銅金屬層，再 .以銅金屬層爲植種層，進行電鍍銅製程，以形成銅導線於 配線溝渠中。 本發明之接觸窗插塞於終止層上之突出部份》可增力α '接觸窗插塞與金屬導線間之接觸面積，因而降低了接觸電 阻。同時，依化學氣相沉積法所沉積之黏著層與導電材料， 經回蝕刻步驟後，於接觸窗插塞之突出部份之側壁所形$ 之間隙壁，可以解決上述接觸窗插塞側壁角落之微溝問 題。 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1A圖至第1E圖所繪示爲習知金屬鑲嵌之製造流梃 剖面圖；以及 第2A圖至第2F圖所繪示爲依照本發明之較佳實施例 金屬鑲嵌之製造流程剖面圖。 圖式之標記說明： 100、200 :基底 102、202 :源極/汲極 6 本纸張尺度適用中國國家標準（CNS ) A4規格（2〖0X297公釐） (請先閲讀背面之注意事項再填寫本耳』In the case of 0.18 micron or even smaller generation, the contact resistance becomes larger due to the reduction of the contact window area, which has become an urgent problem to be overcome in semiconductor engineering. The size of the contact resistance of the contact window structure depends on the contact area. When the contact area is larger, the resistance of the contact resistance is usually smaller. Therefore, the present invention provides a method for manufacturing a contact plug in a metal inlay process. Method to make a contact window structure with low contact resistance. However, during the fabrication of this contact window structure, microtrenching occurred in the corners of the sidewalls of the contact window plug when wiring trenches were formed in the oxide layer using lithographic etching technology. Therefore, the present invention utilizes a chemical vapor deposition method to form a gap wall on the side wall of the protruding portion of the contact window plug, thereby avoiding the problem of micro grooves. One: According to the above and other objects of the present invention, a method for manufacturing a metal inlay is proposed. First, a substrate is provided, and an active / drain region has been formed on the substrate. Then, an inner dielectric material is formed on the substrate, and the inner dielectric material is planarized according to a chemical mechanical honing method. A termination layer is formed on the electrical layer. After that, a first oxide layer is formed on the termination layer, and then a lithography process is performed to open the contact window in the first oxide layer, the termination layer and the dielectric layer, and expose the source / drain electrodes. After that, a conductive material is deposited on the first oxide layer to fill the opening of the contact window, and the conductive material on the second oxide layer is removed to form a contact window plug. Then deposit a second oxide layer on the first oxide layer, and then perform a lithographic etching process to form wiring trenches in the first oxide layer and the second oxide layer, and use the stop layer as an etching stop layer to make the contact window insert The plug protrudes from the surface of the termination layer. Then 'according to the chemical vapor deposition method' is deposited on the termination layer-layer adhesion layer (glue 5 This paper size applies Chinese National Standard (CNS) A4 specification (2i0x297)) ---------- -(Please read the precautions on the back before filling out this page) Order the A7 B7 4 514 0 6 5888twf.doc / 008 .i, Invention Description (γ) layer of the Consumer Cooperative of Intellectual Property Bureau of the Ministry of Economic Affairs, and then follow the instructions The chemical vapor deposition method deposits a conductive layer on the adhesive layer and covers the protruding portion of the contact window plug, and then performs a back-etching step to form a gap wall on the sidewall of the protruding portion of the contact window plug. Beta stomach deposits a diffUsion barrier layer on the adhesive layer and the contact window plug. Then, a copper metal layer is deposited on the diffusion barrier layer, and the copper metal layer is used as the seed layer for electroplating. Copper process to form copper wires in wiring trenches. The protruding portion of the contact window plug on the termination layer of the present invention can increase the contact area between the contact window plug and the metal wire, thereby reducing the contact resistance. At the same time, after the etch-back step of the adhesive layer and the conductive material deposited by the chemical vapor deposition method, a gap wall formed on the side wall of the protruding portion of the contact window plug can solve the corner of the side wall of the contact window plug. The micro groove problem. In order to make the above and other objects, features, and advantages of the present invention more comprehensible, a preferred embodiment is described below in detail with the accompanying drawings' as follows: Brief description of the drawings: Figure 1A to FIG. 1E is a cross-sectional view of a conventional metal inlay manufacturing process; and FIGS. 2A to 2F are cross-sectional views of a manufacturing process of a metal inlay according to a preferred embodiment of the present invention. Explanation of drawing symbols: 100, 200: substrate 102, 202: source / drain 6 This paper size is applicable to China National Standard (CNS) A4 specification (2 〖0X297mm） (Please read the precautions on the back before Fill in this ear
經濟部智慧財產局員工消費合作社印製 4 0 6 A7 B7 5 8 88twf. doc/008 五、發明説明（ί ) 104、204 :介電層 106、206 :終止層 108 :接觸窗開口內之金屬鎢 (請先閱讀背面之注意事項再填寫本頁) 110、210 :接觸窗開口 112、212 :接觸窗插塞 120、220 :金屬層 122、208 :第一氧化層 124、216 :配線溝渠 212a :接觸窗插塞之突出部份 212b:間隙壁 214 :第二氧化層 218 :黏著層 222 :擴散障礙層 實施例 ' 請參照第2A圖至第2F圖，其繪示依照本發明之較佳 實施例，一種金屬鑲嵌之製造流程剖面圖。 經濟部智慧財產局員工消費合作社印製 請參照第2A圖，提供一基底200，而基底上已形成 有一源極/汲極區202，於基底200上形成介電層204，再 進行化學機械硏磨，以平坦化介電層204。接著依序形成 終止層206與第一氧化層208於介電層204上。終止層之 形成方法，例如可爲低壓化學氣相沉積法，而其材質包括 氮化砂或氮氧化砂。 請參照第2B圖，在第一氧化層208上旋塗一層光阻 劑，經由微影蝕刻製程，以形成接觸窗開口 210於第一氧 7 本紙張尺度適用中國國家標準（CNS ) A4規格（210X297公釐） 451406 5888twf.doc/008 _____B7 五、發明説明（t) 化層208、終止層206與介電層2〇4中，並曝露出源極/汲 極 202。 請參照第2C圖’沉積導電材料於第一氧化層2〇8上， 以塡滿該接觸窗開口 210。而導電材料之沉積方法例如可 爲化學氣相ί几積法，而其材質包括鎢。並去除位於第一氧 化層208上之導電材料，以形成接觸窗插塞2丨2。去除導 電材料之方法包括化學機械硏磨法。 請參照第2D圖，形成第二氧化層2Μ於第一氧化層 208上。進行一微影蝕刻製程，以形成配線溝渠216於第 —氧化層2〇8與第二氧化層2U中，並以終止層2〇6爲蝕 刻終止層’使得接觸窗插塞212突出於終止層206表面， 而配線溝渠216之底層爲蝕刻終止層206。 請參照第2Ε圖，沉積一層黏著層218於終止層206 上。黏著層218之沉積方法’例如可爲化學氣相沉積法， 其材質包括氮化鈦。再沉積一層導電材料於黏著層218上， 並覆蓋接觸窗插塞212之突出之部份2Ua。導電材料之沉 積方法’例如可爲化學氣相沉積法，而其材質包括鎢。再 進行回蝕刻步驟，以形成間隙壁2Ub於接觸窗插塞212 之突出之部份212a的側壁。回蝕刻之方法，例如可爲反 應性離子蝕刻法。 請參照第2F圖，沉積擴散障礙層22：2於黏著層上與 接觸窗插塞上。擴散障礙層222之沉積方法，例如可爲物 理氣相沉積法，其材質包括氮化妲。再依化學氣相沉積法 沉積一層銅金屬層爲植種層（seeding layer)，進行一電 8 本紙張尺度適用中國國家檩準（CMS ) Α4规格（210 X 2.97公釐） -----------ο衣II (請先閲讀背面之注意事項再填寫本頁) -β 經濟部智慧財產局員工消費合作社印製 A7 B7 經濟部智慧財產局員工消費合作社印製 451406 5888twf*doc/008 五、發明説明Π ) 鍍銅製程，以形成一銅金屬導線220於配線溝渠216中’ 並與接觸窗插塞212電性連接。 由上述本發明較佳實施例可知，接觸窗插塞突出於終 止層上之部份，可增加接觸窗插塞與金屬導線間之接觸面 .積，因而降低了接觸電阻。同時，依化學氣相沉積法所沉 積之黏著層與導電層，經回蝕刻步驟後，於導電材料插塞 之突出部份的側壁所彤成之間隙壁，可以解決在製作此接 觸窗結構過程中，利用微影蝕刻技術，在氧化層中形成配 線溝渠時，所造成的接觸窗插塞凸出部分之側壁靠近終止 層頂端角落處之微溝問題。而使得後續依物理氣相沉積 法，沉積的擴散障礙層能有較佳的階梯覆蓋能力，因此後 續形成之銅金屬層可以沉積於有較佳的階梯覆蓋能力之擴 散障礙層上，因而防止了元件漏電（leakage)現象之發生， 進而增加了元件的可靠度。 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。 木紙張尺度適用中國國家標準（CNS〉A4規格（210X297公釐） (請先閲讀背面之注意事項再填寫本頁)Printed by the Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs 4 0 6 A7 B7 5 8 88twf.doc / 008 V. Description of the Invention (ί) 104, 204: Dielectric layer 106, 206: Termination layer 108: Metal in contact window opening Tungsten (please read the precautions on the back before filling this page) 110, 210: contact window openings 112, 212: contact window plugs 120, 220: metal layers 122, 208: first oxide layers 124, 216: wiring trenches 212a : Protruding portion 212b of the contact window plug: spacer 214: second oxide layer 218: adhesive layer 222: diffusion barrier layer embodiment 'Please refer to FIG. 2A to FIG. 2F, which illustrate the preferred method according to the present invention. The embodiment is a sectional view of a manufacturing process of metal inlay. Printed by the Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economics Please refer to FIG. 2A to provide a substrate 200, and a source / drain region 202 has been formed on the substrate. A dielectric layer 204 is formed on the substrate 200, and then chemical mechanical is performed. Grinding to planarize the dielectric layer 204. Then, a stop layer 206 and a first oxide layer 208 are sequentially formed on the dielectric layer 204. The method for forming the termination layer may be, for example, a low pressure chemical vapor deposition method, and the material thereof includes nitrided sand or oxynitride sand. Please refer to FIG. 2B, a layer of photoresist is spin-coated on the first oxide layer 208, and a lithographic etching process is performed to form a contact window opening 210 in the first oxygen. 210X297 mm) 451406 5888twf.doc / 008 _____B7 V. Description of the invention (t) In the chemical layer 208, the termination layer 206 and the dielectric layer 204, the source / drain 202 is exposed. Referring to FIG. 2C, a conductive material is deposited on the first oxide layer 208 to fill the contact window opening 210. The method for depositing the conductive material may be, for example, a chemical vapor deposition method, and its material includes tungsten. The conductive material on the first oxide layer 208 is removed to form a contact window plug 2 2. Methods for removing conductive materials include chemical mechanical honing. Referring to FIG. 2D, a second oxide layer 2M is formed on the first oxide layer 208. A lithographic etching process is performed to form a wiring trench 216 in the first oxide layer 208 and the second oxide layer 2U, and the stop layer 206 is used as an etching stop layer so that the contact window plug 212 protrudes from the stop layer. 206 surface, and the bottom layer of the wiring trench 216 is an etch stop layer 206. Referring to FIG. 2E, an adhesive layer 218 is deposited on the termination layer 206. The deposition method of the adhesive layer 218 may be, for example, a chemical vapor deposition method, and the material thereof includes titanium nitride. A further layer of conductive material is deposited on the adhesive layer 218 and covers the protruding portion 2Ua of the contact window plug 212. The deposition method of the conductive material may be, for example, a chemical vapor deposition method, and its material includes tungsten. Then, an etch-back step is performed to form the spacer 2Ub on the side wall of the protruding portion 212a of the contact window plug 212. The etch-back method may be, for example, a reactive ion etching method. Referring to FIG. 2F, a diffusion barrier layer 22: 2 is deposited on the adhesive layer and the contact window plug. The method for depositing the diffusion barrier layer 222 may be, for example, a physical vapor deposition method, and the material thereof includes hafnium nitride. Then a copper metal layer was deposited as a seeding layer according to the chemical vapor deposition method, and an electric power was applied. The paper size is applicable to the Chinese National Standard (CMS) A4 specification (210 X 2.97 mm) ----- ------ ο Clothing II (Please read the precautions on the back before filling out this page) -β Printed by the Consumers ’Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs A7 B7 Printed by the Employees’ Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs 451406 5888twf * doc 5. Description of the invention Π) A copper plating process is performed to form a copper metal wire 220 in the wiring trench 216 'and is electrically connected to the contact window plug 212. It can be known from the foregoing preferred embodiments of the present invention that the portion of the contact window plug protruding from the termination layer can increase the contact surface area between the contact window plug and the metal wire, thereby reducing the contact resistance. At the same time, after the adhesion layer and the conductive layer deposited by the chemical vapor deposition method are etched back, the gap formed by the side wall of the protruding portion of the conductive material plug can solve the process of making the contact window structure. In the use of lithographic etching technology, when a wiring trench is formed in an oxide layer, a micro-groove problem is caused at the side wall of the protruding portion of the contact window plug near the top corner of the termination layer. The subsequent deposition of the diffusion barrier layer according to the physical vapor deposition method can have a better step coverage ability, so the subsequently formed copper metal layer can be deposited on the diffusion barrier layer having a better step coverage ability, thereby preventing The occurrence of component leakage has further increased the reliability of the component. Although the present invention has been disclosed as above with a preferred embodiment, 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 determined by the scope of the attached patent application. Wood paper size applies to Chinese national standards (CNS> A4 size (210X297 mm) (Please read the precautions on the back before filling this page)