4294twf.doc/006 A7 B7 經濟部中央檩準局員工消費合作杜印製 五、發明説明（/ ) 本發明是有關於一種製造雙重金屬鑲嵌（Dual Damascene)的方法’且特別是有關於一種形成雙重金屬鑲 嵌接觸窗（Contacts)的方法。 雙重金屬鑲嵌是一種具有多層金屬內連線（MuUUevel Interconnection)的積體電路結構中，同時形成金屬插塞和 內連線的技術。其方法係先在基底上方的介電層中形成雙 重金屬鑲嵌接觸窗，再將導體塡入雙重鑲嵌接觸窗中，形 成金屬插塞與內連線。 習知形成雙重金屬鑲嵌接觸窗的方法是在基底上方形 成一層介電層之後’形成一層餓刻終止層，接著再形成另 一層介電層於蝕刻終止層上方。之後，以光阻層定義內連 線圖案，進行蝕刻步驟，於上層的介電層中形成凹槽。其 中，凹槽並且暴露出部分的蝕刻終止層。之後.，形成另一 .光阻層定義出金屬插塞圖案，並進行另一蝕刻步驟，移除 部分的蝕刻終止層以及下層的介電層，以於下層的介電層 中形成接觸窗開口，而接觸窗開口與凹槽構成雙重鑲嵌接 觸窗。 爲了形成內連線與金屬插塞的不同圖案，有時需要在 介電層中形成一層鈾刻終止層，使得形成介電層的步驟需 要分成兩次來進行，在製程上較爲複雜。另一方面，在形 成雙重金屬鑲嵌接觸窗時，也因爲有此蝕刻終止層而需要 進行兩次的微影蝕刻步驟，這也會使得製程的步驟較爲繁 複。 3 (請先閱讀背面之注意事項寫本頁) .裝· 訂 腺 ί 4294twf.doc/006 . A7 -----------B7 — 五、發明説明（上） ^ 一~ 因此’本發明提供-種製造雙重金屬鑲嵌的方法。此-方法是提供-個具有介電層的基底，於介電層上形成一層 具有雙重金屬鑲肷接觸窗圖案的光阻層，並以此光阻層爲 餓刻罩幕，對介電層進行鈾刻步驟，於介電層中形成雙重 金屬ϋ黯馳，痛導體塡入雙·麵織觸窗中， 以形成雙重金J1鑲嵌。由於光阻層的圖案可以藉由蝕刻步 驟轉移至介電層中，因此如果在光阻腿光時，同時定義 金屬插塞接觸窗以及內連線的圖案，則也可以於介電層中 同時形成金屬插塞以及內連線。 爲了使得光阻層中能具有雙重金屬鑲嵌接觸窗的圖 案，光阻層由第一光阻層與第二光阻層所構成。形成光阻 層的方法有兩種，第一種方法是在介電層上塗佈第一光阻 層，進行曝光以定義第一光阻層之圖案。接著，不經過顯 影步驟就直接塗佈第二光阻層於第一光阻層上，進行曝光 以定義第二光阻層之圖案。接著，再進行顯影的步驟，形 成光阻層。 第二種形成光阻層的方法則是在定義第一光阻層之圖 案之後即進行顯影步驟，再塗佈光阻物質於第一光阻層以 及介電層上方。之後，定義第二光阻層的圖案並且顯影， 以形成光阻層。 此外，具有雙重金屬鑲嵌結構之光阻層也可以使用於 具有蝕刻終止層的介電層結構，其方法是在基底上方依序 形成下層介電層、蝕刻終止層與上層介電層以形成介電 層，並於上層介電層上形成具有雙重鑲嵌結構之光阻層。 本紙張尺度適用中國國家標準（CNS ) Α4规格（210X297公釐） 4294twf.doc/006 A7 B7 五、發明説明（3 ) 之後，進行蝕刻步驟，於介電層中形成雙重金屬鑲嵌接觸 窗，並且塡入導體以形成雙重金屬鑲嵌。 本發明的優點在於形成雙重金屬鑲嵌接觸窗時，可以 連續地進行塗佈光阻物質以及曝光的步驟，並且只進行一 次蝕刻，因此可以簡化製程。另外，可以藉由控制光阻層 與介電層之間的蝕刻選擇比以及光阻層的厚度，來掌握內 連線的深度以及不論介電層中是否具有蝕刻終止層，都可 以形成雙重金屬鑲嵌。 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，其中： 第1A圖至第1C圖係繪示根據本發明之一較佳實施例 之第一種形成光阻層之方法的流程剖面圖； 第2A圖至第2B圖係繪示根據本發明之一較佳實施例 之第二種形成光阻層之方法的流程剖面圖； 第3A圖至第3C圖係繪示依照本發明之一較佳實施例 之第一種形成雙重金屬鑲嵌之方法的流程剖面圖；以及 第4A圖至第4C圖係繪示依照本發明之一較佳實施例 之第二種形成雙重金屬鑲嵌之方法的流程剖面圖。 圖式之標記說明： 100、200、300、400 :基底 102、202、302 :介電層 104、204 :第一光阻層 104a :第一變質層 5 本紙張尺度適用中國國家標準（CNS ) A4規格（210X297公釐） 4294t wf.doc/006 Λ7 B7 經濟部中央標準扃J工消費合作社印製 五、發明説明（f·) 106、206 ··第二光阻層 106a :第二變質層 108、208、304、414 :光阻層 110、210、408 :雙重金屬鑲嵌接觸窗圖案 112、212、410 :內連線圖案 114、214、412 :金屬插塞接觸窗圖案 3〇6 ’ 4丨6 :雙重金屬鑲嵌接觸窜 308、428 :內連線凹槽 310、430 :金屬插塞接觸窗 312、422 :襯層 314、424 :導電層 316、426 :雙重金屬鑲嵌 318、428:內連線 320、430 :金屬插塞 402 :下層介電層 404 :鈾刻終止層 406 :上層介電層.實施例 請參照第1A圖，在已形成有介電層102的基底1〇〇 上方形成第一光阻層104，並進行曝光，使部分的第一光 阻層104變質爲第一變質層l〇4a。其中，形成第一光阻層 104的方法比如爲在介電層102上塗佈一層負光阻，或是 於塗佈負光阻之後再進行軟烤（Soft Bake)的步驟。軟烤的 作用在於去除光阻中的溶劑、增加光阻的附著力以及增加 6 本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^寫本頁) .裝· 訂 線- 4294twf.doc/006 A7 _ B7_ 五、發明説明（S) 後續步驟中所使用之顯影劑對曝光與未曝光之光阻的選擇 性等等。 請參照第1B圖，於第一光阻層1〇4以及第一變質層 104a上形成第二光阻層106，並進行曝光，使部分的第二 光阻層106變成第二變質層106a。其中形成第二光阻層1〇6 的方法比如爲塗佈一層負光阻於第一光阻層104上，或是 先塗佈負光阻並且進行軟烤。 _ 請參照第1C圖’進行顯影步驟，以移除第一變質層1 〇4a 與第二變質層106a，或是於顯影步驟之後再進行硬烤(Hard Bake)步驟，形成光阻層108。其中光阻層1〇8比如具有雙 重金屬鑲嵌接觸窗圖形110、內連線圖形112以及金屬插 塞接觸窗圖形114。 此外，也可以用另一種方法形成光阻層。 經濟部中失標準局員工消費合作社印製 請參照第2A圖，於已形成有介電層202的基底200 上方形成第一光阻層204。形成第一光阻層204的方法比 如爲在介電層202上方塗佈一層負光阻，並且進行軟烤步 驟。接著.，對第一光阻層204進行曝光步驟並且顯影，或 是於顯影之後又進行硬烤步驟，以定義出特定圖案，並且 暴露出部分的介電層202。 請參照第2B圖，形成第二光阻層206覆蓋於第一光 阻層204以及介電層202上。形成第二光阻層206的方法 比如爲塗佈一層光阻物質覆蓋於第一光阻層204。接著’ 進行曝光或是進行曝光並軟烤’在顯影或是顯影並硬烤之 後，形成具有特定圖案之第二光阻層206。其中，第一光 7 本紙張尺度適用中國國家標準（CNS ) A4規格（2丨〇><297公瘦） 4294twf.doc/006 A7 B7 經濟部中夬榡準局員工消費合作社印製 五、發明説明（β) 阻層204與第二光阻層206構成了光阻層208,而光阻層208 比如具有雙重金屬鑲嵌接觸窗圖形210、內連線圖形212 以及金屬插塞接觸窗圖形214。 請參照第3A圖，在具有介電層302的基底300上方 形成具有欲形成之雙重鑲嵌接觸窗結構之光阻層304。其 中’形成光阻層304的方法比如爲前述兩種方法其中之一。 請參照第3B圖，移除部分的介電層302，以形成雙重 鑲嵌接觸窗306、內連線凹槽308以及金屬插塞接觸窗310， 並移除光阻層304。其中，移除部分的介電層302之方法 比如爲藉由控制介電層302與光阻層304的蝕刻選擇比， 進行非等向性蝕刻，以將光阻層304中所具有之圖案轉移 至介電層302。 請參照第3C圖，沿著於介電層302的表面形成一層 襯層(Liner Layer)312，再形成一層導電層314於襯靥312 上’以形成雙重金屬鑲嵌316、內連線318以及金屬插塞 320。 請參照第4A圖，除了上述的方法外，另一種製作雙 重金屬鑲嵌的方法是在基底400上依序形成下層介電餍 402、蝕刻終止層404以及上層介電層406，並於上靥介電 層406上形成具有雙重鑲嵌接觸窗圖形408、內連線圖形 410以及金屬插接觸窗圖形412的光阻層414。其中，形成 光阻層414的方法比如爲前述兩種形成光阻層之方法其中 之一。 接著，請參照第4B圖，移除部分的上層介電層406、 請 先 閲 讀 背 意 事 項 本 頁 裝 訂 本紙張尺度適用中國國家標準（CNS ) A4規格（210X297公釐） 4294t\vf.doc/006 A7 ______B7 _ 五、發明説明（7) 蝕刻終止層404以及下層介電層406，以形成雙重鑲嵌接 觸窗416、內連線凹槽418以及金屬插塞接觸窗420。其方 法比如爲控制光阻層414、上層介電層406、蝕刻終止層404 以及下層介電層402之間的蝕刻選擇比，進行非等向性蝕 刻至暴露出部分之基底400爲止。 請參照第4C圖，移除光阻層414，並形成襯層422 以及導電層424。其中，導電層424比如爲具有雙重金屬 鑲嵌426、內連線428以及金屬插塞430等結構。 本發明之特徵在於形成具有雙重金屬鑲嵌接觸窗圖 形、內連線圖形以及金屬插塞圖形之光阻層。並且以一次 蝕刻的方式將光阻層的圖形轉移至介電層中。由於蝕刻的 次數只有一次，因此可以簡化製程。此外，藉由控制光阻 層與介電層之間的鈾刻選擇比，可以控制所形成之內連線 在介電層中的深度。以及在不論是否具有蝕刻終止層的情 形下，都能以一次的蝕刻步驟，在介電層中形成雙重金屬 鑲嵌接觸窗、內連線凹槽以及金屬插塞接觸窗。 雖然本發明已以一較佳實施例說明如上，可瞭解任何 在不脫離本發明之精神和範圍內可作各種之更動與潤飾。 9 本紙張尺度適用中國國家標準（CNS ) A4規格（210X297公釐）4294twf.doc / 006 A7 B7 Printed by the consumer cooperation of the Central Procurement Bureau of the Ministry of Economic Affairs. 5. Description of the invention (/) The present invention relates to a method for manufacturing dual metal inlays (Dual Damascene), and in particular to a method for forming Method of double metal inlaid contact windows. Dual metal damascene is a technology that simultaneously forms metal plugs and interconnects in an integrated circuit structure with multilayer metal interconnects (MuUUevel Interconnection). The method is to form a double heavy metal inlaid contact window in the dielectric layer above the substrate, and then insert the conductor into the double inlaid contact window to form metal plugs and interconnects. The conventional method for forming a double-metal damascene contact window is to form a dielectric layer on the substrate after forming a dielectric layer, and then form another dielectric stop layer over the etching stop layer. Then, a photoresist layer is used to define the interconnect pattern, and an etching step is performed to form a recess in the upper dielectric layer. Among them, the grooves also expose part of the etch stop layer. After that, another photoresist layer is formed to define a metal plug pattern, and another etching step is performed to remove a part of the etch stop layer and the underlying dielectric layer to form a contact window opening in the underlying dielectric layer. , And the contact window opening and the groove constitute a double mosaic contact window. In order to form different patterns of interconnects and metal plugs, it is sometimes necessary to form a uranium etch stop layer in the dielectric layer, so that the step of forming the dielectric layer needs to be divided into two steps, which is more complicated in the manufacturing process. On the other hand, when forming a double metal damascene contact window, the lithography etching step needs to be performed twice because of the etch stop layer, which also makes the process steps more complicated. 3 (Please read the notes on the back first to write this page). Binding and binding glands 4294twf.doc / 006. A7 ----------- B7 — V. Description of the Invention (Part 1) ^ I ~ Therefore 'The present invention provides a method of making a dual metal inlay. This method is to provide a substrate with a dielectric layer, and form a photoresist layer with a double metal inlay contact window pattern on the dielectric layer, and use the photoresist layer as a mask to mark the dielectric layer. Carrying out the uranium engraving step to form a double metal plutonium in the dielectric layer, and the pain conductor is inserted into the double-face weaving touch window to form a double gold J1 inlay. Since the pattern of the photoresist layer can be transferred to the dielectric layer through the etching step, if the pattern of the metal plug contact window and the interconnect is defined at the same time when the photoresist is exposed, it can also be simultaneously in the dielectric layer. Form metal plugs and interconnects. In order to make the photoresist layer have a double metal mosaic contact window pattern, the photoresist layer is composed of a first photoresist layer and a second photoresist layer. There are two methods of forming the photoresist layer. The first method is to coat the first photoresist layer on the dielectric layer and perform exposure to define the pattern of the first photoresist layer. Then, a second photoresist layer is directly coated on the first photoresist layer without undergoing a developing step, and exposure is performed to define a pattern of the second photoresist layer. Then, the developing step is performed to form a photoresist layer. The second method of forming the photoresist layer is to perform a developing step after defining the pattern of the first photoresist layer, and then apply a photoresist substance to the first photoresist layer and the dielectric layer. After that, a pattern of the second photoresist layer is defined and developed to form a photoresist layer. In addition, a photoresist layer with a dual metal damascene structure can also be used in a dielectric layer structure with an etch stop layer. The method is to sequentially form a lower dielectric layer, an etch stop layer and an upper dielectric layer over the substrate to form a dielectric. An electrical layer, and a photoresist layer having a dual damascene structure is formed on the upper dielectric layer. This paper size applies the Chinese National Standard (CNS) A4 specification (210X297 mm) 4294twf.doc / 006 A7 B7 V. Description of the invention (3), after the etching step, a double metal inlaid contact window is formed in the dielectric layer, and The conductor is pierced to form a double metal inlay. The advantage of the present invention is that when forming a double metal inlaid contact window, the steps of applying a photoresist substance and exposing can be performed continuously, and only one etching is performed, so the process can be simplified. In addition, by controlling the etching selection ratio between the photoresist layer and the dielectric layer and the thickness of the photoresist layer, the depth of the interconnects and whether or not the dielectric layer has an etch stop layer can be used to form a double metal. mosaic. In order to make the above and other objects, features, and advantages of the present invention more comprehensible, a preferred embodiment is given below and described in detail in conjunction with the accompanying drawings, wherein: Figures 1A to 1C are FIG. 2A to FIG. 2B are flow sectional views showing a first method of forming a photoresist layer according to a preferred embodiment of the present invention; FIGS. 2A to 2B are views showing a second formation according to a preferred embodiment of the present invention. Process flow sectional views of a method of a photoresist layer; FIGS. 3A to 3C are flow sectional views showing a first method for forming a dual metal damascene according to a preferred embodiment of the present invention; and FIGS. 4A to 4 FIG. 4C is a cross-sectional view showing a flow of a second method for forming a dual metal damascene according to a preferred embodiment of the present invention. Explanation of the marks in the drawings: 100, 200, 300, 400: substrates 102, 202, 302: dielectric layers 104, 204: first photoresist layer 104a: first metamorphic layer 5 This paper is applicable to Chinese National Standards (CNS) A4 specification (210X297 mm) 4294t wf.doc / 006 Λ7 B7 Printed by the Central Standard of the Ministry of Economic Affairs 印 Printed by J.J. Consumer Cooperatives V. Description of the invention (f ·) 106, 206 ·· Second photoresist layer 106a: second modified layer 108, 208, 304, 414: Photoresist layers 110, 210, 408: Double metal inlaid contact window patterns 112, 212, 410: Interconnect patterns 114, 214, 412: Metal plug contact window patterns 306 '4丨 6: Double metal inlay contact channel 308, 428: Interconnect grooves 310, 430: Metal plug contact window 312, 422: Liner layer 314, 424: Conductive layer 316, 426: Double metal inlay 318, 428: Inner Lines 320 and 430: metal plug 402: lower dielectric layer 404: uranium etch stop layer 406: upper dielectric layer. For an example, refer to FIG. 1A, above the substrate 100 on which the dielectric layer 102 has been formed. A first photoresist layer 104 is formed and exposed, so that a portion of the first photoresist layer 104 is modified into the first modified layer 104a. The method for forming the first photoresist layer 104 is, for example, applying a negative photoresist on the dielectric layer 102, or performing a soft baking step after applying the negative photoresist. The role of soft baking is to remove the solvent in the photoresist, increase the adhesion of the photoresist, and increase the size of this paper. Applicable to the Chinese National Standard (CNS) A4 specification (210X297 mm) (please read the precautions on the back before writing) (Page). Binding and binding-4294twf.doc / 006 A7 _ B7_ V. Description of the invention (S) Selectivity of the developer used in the subsequent steps to the exposed and unexposed photoresist, etc. Referring to FIG. 1B, a second photoresist layer 106 is formed on the first photoresist layer 104 and the first modified layer 104a, and exposure is performed so that a portion of the second photoresist layer 106 becomes the second modified layer 106a. The method for forming the second photoresist layer 106 is, for example, coating a negative photoresist on the first photoresist layer 104, or first coating the negative photoresist and performing soft baking. _ Please refer to FIG. 1C to perform a developing step to remove the first modified layer 104a and the second modified layer 106a, or to perform a hard baking step after the developing step to form the photoresist layer 108. The photoresist layer 108 has, for example, a double heavy metal inlaid contact window pattern 110, an interconnection pattern 112, and a metal plug contact window pattern 114. Alternatively, the photoresist layer may be formed by another method. Printed by the Consumers' Cooperative of the Bureau of Loss and Standards, Ministry of Economic Affairs Please refer to FIG. 2A. A first photoresist layer 204 is formed over the substrate 200 on which the dielectric layer 202 has been formed. The method of forming the first photoresist layer 204 is, for example, coating a negative photoresist on the dielectric layer 202 and performing a soft baking step. Next, the first photoresist layer 204 is subjected to an exposure step and developed, or a hard bake step is performed after the development to define a specific pattern, and a portion of the dielectric layer 202 is exposed. Referring to FIG. 2B, a second photoresist layer 206 is formed to cover the first photoresist layer 204 and the dielectric layer 202. A method for forming the second photoresist layer 206 is, for example, coating a photoresist material to cover the first photoresist layer 204. Next, "exposure or exposure and soft baking" is followed by development or development and hard baking, to form a second photoresist layer 206 having a specific pattern. Among them, the first light 7 paper size is applicable to the Chinese National Standard (CNS) A4 specification (2 丨 〇 < 297 male thin) 4294twf.doc / 006 A7 B7 Printed by the Consumers' Cooperative of the China Central Standards Bureau of the Ministry of Economic Affairs Explanation of the invention (β) The resist layer 204 and the second photoresist layer 206 constitute a photoresist layer 208, and the photoresist layer 208, for example, has a double metal mosaic contact window pattern 210, an interconnect pattern 212, and a metal plug contact window pattern. 214. Referring to FIG. 3A, a photoresist layer 304 having a dual damascene contact window structure to be formed is formed over a substrate 300 having a dielectric layer 302. The method of forming the photoresist layer 304 is, for example, one of the two methods described above. Referring to FIG. 3B, a portion of the dielectric layer 302 is removed to form a dual damascene contact window 306, an interconnect groove 308, and a metal plug contact window 310, and the photoresist layer 304 is removed. The method for removing a part of the dielectric layer 302 is, for example, controlling an etching selection ratio between the dielectric layer 302 and the photoresist layer 304, and performing anisotropic etching to transfer a pattern in the photoresist layer 304. To the dielectric layer 302. Referring to FIG. 3C, a liner layer 312 is formed along the surface of the dielectric layer 302, and then a conductive layer 314 is formed on the liner 312 to form a double metal damascene 316, an interconnect 318, and a metal. Plug 320. Please refer to FIG. 4A. In addition to the above method, another method for making a dual metal damascene is to sequentially form a lower dielectric 餍 402, an etching stop layer 404, and an upper dielectric layer 406 on the substrate 400. A photoresist layer 414 having a double damascene contact window pattern 408, an interconnect pattern 410, and a metal plug contact window pattern 412 is formed on the electrical layer 406. The method for forming the photoresist layer 414 is, for example, one of the two methods for forming the photoresist layer. Next, please refer to Figure 4B, remove part of the upper dielectric layer 406, please read the note first. This page is bound. The paper size applies the Chinese National Standard (CNS) A4 specification (210X297 mm) 4294t \ vf.doc / 006 A7 ______B7 _ V. Description of the invention (7) The etching stop layer 404 and the lower dielectric layer 406 are etched to form a dual damascene contact window 416, an interconnect groove 418, and a metal plug contact window 420. The method is, for example, controlling the etching selection ratio among the photoresist layer 414, the upper dielectric layer 406, the etch stop layer 404, and the lower dielectric layer 402, and performing anisotropic etching to the exposed portion of the substrate 400. Referring to FIG. 4C, the photoresist layer 414 is removed, and a liner layer 422 and a conductive layer 424 are formed. Among them, the conductive layer 424 has a structure such as a double metal damascene 426, an interconnect 428, and a metal plug 430. The present invention is characterized by forming a photoresist layer having a double metal damascene contact window pattern, an interconnect pattern, and a metal plug pattern. And the pattern of the photoresist layer is transferred to the dielectric layer by one etching. Since the etching is performed only once, the process can be simplified. In addition, by controlling the uranium etch selection ratio between the photoresist layer and the dielectric layer, the depth of the formed interconnects in the dielectric layer can be controlled. And regardless of whether or not an etch stop layer is present, a double metal damascene contact window, an interconnect groove, and a metal plug contact window can be formed in the dielectric layer in a single etching step. Although the present invention has been described above with reference to a preferred embodiment, it is to be understood that various changes and modifications can be made without departing from the spirit and scope of the invention. 9 This paper size applies to China National Standard (CNS) A4 (210X297 mm)