519724 7264twf.doc/006 B7 五、發明說明（丨） 本發明是有關於一種在晶圓表面上形成銲墊開口（pad_ open)與保險絲開口（fuse-open)之製程，且特別是有關於一 種在晶圓表面上利用一次微影形成銲墊開口與保險絲開口 之形成方法。 習知在晶圓表面之銲墊開口與保險絲開口之形成方法 係在已形成有銲墊與保險絲之晶圓上依序形成保護層 (Passivation)與光阻層，再進行微影蝕刻步驟，以形成銲墊 開口與保險絲開口。 在上述進行微影蝕刻之步驟中，必需對銲墊開口進行 過蝕刻，以完全去除銲墊表面之保護層，以暴露出銲墊之 金屬層表面’且保險絲開口之底部至保險絲之間也必需存 在有一定厚度之保護層，以防止保險絲暴露出來。然而， 位於銲墊位置上方之保護層與位於保險絲位置上方之保護 層係於同一沈積製程所沈積而成，因此兩者之厚度相同。 又，在進行微影蝕刻製程中，兩者所招受之蝕刻力，也是 相同的，所以在暴露出銲墊的同時，也會暴露出保險絲， 而使生產之晶圓的線路與規格不符，並致使產品良率下 降。 另外，位於銲墊表面之金屬保護層，其抗触刻能力遠 高於保護層之抗蝕刻能力，且因保險絲開口需完全含括整 個區域之保險絲，因而在形成銲墊開口的蝕刻製程中，位 於邊緣保險絲與保險絲開口之間的保護層會在暴露出保險 絲的问時’触芽形成溝渠，進而破壞晶圓本身之電路設計， 降低產品良率。 3 本紙張尺度適用中國國家標準（CNS)A4規格（21〇 X 297公釐） (請先閱讀背面之注意事項再填寫本頁)519724 7264twf.doc / 006 B7 V. Description of the invention (丨) The present invention relates to a process for forming a pad_open and fuse-open on a wafer surface, and particularly relates to a process A method for forming a pad opening and a fuse opening on a wafer surface by one-time lithography. The conventional method for forming the pad opening and the fuse opening on the wafer surface is to sequentially form a protection layer and a photoresist layer on the wafer on which the pad and the fuse have been formed, and then perform a lithography etching step to A solder pad opening and a fuse opening are formed. In the above-mentioned lithographic etching step, the pad opening must be over-etched to completely remove the protective layer on the surface of the pad to expose the surface of the metal layer of the pad, and the bottom of the fuse opening to the fuse must also be There is a protective layer of certain thickness to prevent the fuse from being exposed. However, the protective layer above the pad position and the protective layer above the fuse position are deposited in the same deposition process, so the thickness of both is the same. In addition, in the lithography etching process, the etching force applied by the two is also the same. Therefore, when the solder pad is exposed, the fuse is also exposed, so that the circuit of the produced wafer does not conform to the specifications. And cause the product yield to decline. In addition, the metal protective layer on the surface of the pad has an anti-etching ability much higher than the anti-etching ability of the protective layer, and because the fuse opening needs to completely include the entire area of the fuse, in the etching process of forming the pad opening, The protective layer located between the edge fuse and the fuse opening will contact the bud to form a trench when the fuse is exposed, thereby destroying the circuit design of the wafer itself and reducing the product yield. 3 This paper size applies to China National Standard (CNS) A4 (21〇 X 297 mm) (Please read the precautions on the back before filling this page)
-* ϋ I ·ϋ ·ϋ 1 n _1 一-口，« ϋ ϋ ϋ tap n n I 經濟部智慧財產局員工消費合作社印製 經濟部智慧財產局員工消費合作社印製 519724 7264twf.doc/006 B7 五、發明說明（z) 因此，習知爲解決上述問題而提出之改良式蝕刻製程 係在已形成有靜墊與保險絲之晶圓上依序形成保護層跑光 阻層，再分別於靜墊與保險絲之位置，各別進行一次微影 蝕刻，即藉由兩次不同蝕刻程度之蝕刻製程，以完成銲塾 開口與保險絲開口。 利用前述之改良式蝕刻製程確實能有效地解決上述之 兩種問題，然而，此改良式蝕刻製程必需進行兩次飽刻製 程，導致整體製程之製程時間的增加以及生產成本之提 高。 本發明爲同時解決上述之問題，提出一種銲墊開口與 保險絲開口之形成方法，利用一次蝕刻製程，以同時解決 上述之問題，進而減少製程步驟、增加產品良率並降低生 產成本。 本發明提出一種銲墊開口與保險絲開口之形成方法， 係在已形成有銲墊與保險絲之晶圓上依序形成保護層與光 阻層，進行一次曝光顯影步驟，以完全移除位於銲墊上方 之光阻層，及移除部分位於保險絲上方之光阻層。接著， 進行蝕刻步驟，完全移除位於銲墊上方之保護層，及移除 位於保險絲上方之光阻層與部分保護層，最後，移除光阻 層。 本發明之光阻層可在曝光顯影之後，於保險絲之位置 之上仍保留一定厚度之光阻層，以在後續進行蝕刻時，防 止蝕刻劑在對銲墊進行過蝕刻之過程中暴露出保險絲，且 當完成蝕刻製程之後，在保險絲開口底部與保險絲之間仍 4-* ϋ I · ϋ · ϋ 1 n _1 One-mouth, «ϋ ϋ ϋ tap nn I Printed by the Employees 'Cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs Printed by the Employees' Cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs 519724 7264twf.doc / 006 B7 Five Explanation of the invention (z) Therefore, the improved etching process proposed to solve the above problems is to sequentially form a protective layer and a photoresist layer on a wafer on which a static pad and a fuse have been formed, and then separately to the static pad and the fuse. In each position, one lithographic etching is performed, that is, two soldering openings and fuse openings are completed through two etching processes with different etching degrees. Using the aforementioned improved etching process can effectively solve the two problems mentioned above. However, this improved etching process must be performed two full-saturation processes, which leads to an increase in the overall process time and an increase in production costs. In order to solve the above problems at the same time, the present invention proposes a method for forming a pad opening and a fuse opening, using a single etching process to solve the above problems at the same time, thereby reducing the process steps, increasing product yield and reducing production costs. The invention provides a method for forming a pad opening and a fuse opening. A protective layer and a photoresist layer are sequentially formed on a wafer on which a pad and a fuse have been formed, and an exposure and development step is performed to completely remove the pads. Square photoresist layer, and remove part of the photoresist layer above the fuse. Then, an etching step is performed to completely remove the protective layer above the bonding pad, remove the photoresist layer and a part of the protective layer above the fuse, and finally, remove the photoresist layer. The photoresist layer of the present invention can retain a certain thickness of the photoresist layer on the fuse position after exposure and development, so as to prevent the etchant from exposing the fuse during the over-etching of the bonding pad during subsequent etching. , And after the etching process is completed, there is still 4 between the bottom of the fuse opening and the fuse.
本紙張尺度適用中國國家標準（CNS)A4規格（21G X 297公tT ------------裝--------訂--------- - (請先閱讀背面之注意事項再填寫本頁) 經濟部智慧財產局員工消費合作社印製 519724 7264twf . doc/ 006 A7 B7 五、發明說明（>) 保有一定厚度之保護層，可增加產品良率並降低生產成 本。 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圖至第5圖所示爲本發明之一較佳實施例之銲墊 開口與保險絲開口之形成方法的示意圖。 圖式之標記說明= 100 :晶圓 1〇2 :銲墊 104 :保險絲 106 :保護層 108 :光阻層 110 :全透光區 、111 :不透光區 112 :半透光區 114 :雙層光罩 116 :光源 118，120 :開口 122 :銲墊開口 124 :保險絲開口 實施例 第1圖至第5圖所示爲本發明之一較佳實施例之銲墊 5 本紙張尺度適用中國國家標準（CNS)A4規格（210 X 297公釐） (請先閱讀背面之注意事項再填寫本頁)This paper size applies to China National Standard (CNS) A4 specification (21G X 297 male tT ------------ installation -------- order ---------- (Please read the notes on the back before filling out this page) Printed by the Consumer Cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs 519724 7264twf .doc / 006 A7 B7 V. Description of the invention (>) Keeping a certain thickness of protective layer can increase product quality In order to make the above and other objects, features, and advantages of the present invention more comprehensible, a preferred embodiment is given below in conjunction with the accompanying drawings to make a detailed description as follows: A brief description of FIGS. 1 to 5 is a schematic diagram of a method for forming a pad opening and a fuse opening according to a preferred embodiment of the present invention. Symbol description of the drawings = 100: wafer 102; pad 104 : Fuse 106: Protective layer 108: Photoresist layer 110: Totally transparent area, 111: Opaque area 112: Semi-transparent area 114: Double-layer photomask 116: Light source 118, 120: Opening 122: Pad opening 124 : Fuse opening embodiment Figures 1 to 5 show the solder pads of a preferred embodiment of the present invention National Standard (CNS) A4 Specification (210 X 297 mm) (Please read the precautions on the back before filling this page)
519724 7264twf·doc/006 A7 B7 五、發明說明（4) (請先閱讀背面之注意事項再填寫本頁) 開口與保險絲開口之形成方法的示意圖。請參照第1圖所 示，在晶圓100之上依序形成金屬層與金屬保護層（未繪 示），再利用微影蝕刻的方法，移除部分金屬層與金屬保 護層，形成銲墊102與保險絲104。其中晶圓100係爲已 完成金屬內連線之半導體元件，金屬層之材質包括銅與鋁 其中之一，金屬保護層之材質包括銅金屬氧化物與鋁金屬 氧化物其中之一。 ‘ 接著，請參照第2圖所示，於晶圓1〇〇之上形成保護 層（Passivation)106，其中保護層106係由至少一層以上之 絕緣材料所構成，絕緣材料之材質係選自於氮化矽、氧化 物與氮氧化合物所組成之族群其中之一，形成保護層106 的方法係包括化學氣相沈積法或物理氣相沈積法。 接著，於保護層106之上形成一層光阻層108，其中 光阻層108係爲正光阻或負光阻，形成光阻層108之方法 包括利用旋轉塗佈法（spm coatmg)將光阻劑塗佈於保護層 106之上，再進行軟烤(soft bake)製程，以移除光阻劑中的 溶劑，形成表面平坦的光阻層108。 經濟部智慧財產局員工消費合作社印製 接著，請參照第3圖所示，進行曝光顯影，以將位於 開口 118部位之光阻層108完全移除，暴露出保護層106, 以及將部分位於開口 120之光阻層108移除，使開口 120 底部與保險絲104之間存在有一定厚度之光阻層108。 在此利用光阻層108爲正光阻爲例進行說明，利用光 源116透過雙層光罩(bi-level mask)114對光阻層108進行 曝光顯影，其中雙層光罩114位於銲墊102上方之部位係 6 本紙張尺度適用中國國家標準（CNS)A4規格（210 X 297公釐） 519724 7264twf.d〇c/006 A7 B7 五、發明說明（c) (請先閱讀背面之注意事項再填寫本頁) 爲全透光（fully transparent)區110,以使光源116完全穿透， 而可利用顯影液移除位於開口 118部位之光阻層108，暴 露出保護層106 ;位於保險絲104上方之部位係爲半透光 (semi-transparent)區112，以使光源116局部穿透，而可利 用顯影液移除位於開口 120之部分光阻層108,並使開口 120底部與保險絲104之間存在有一定厚度之光阻層108 ; 在前述兩位置以外之位置係爲不透光（non-transparent)區 111，以完全阻擋光源116之穿透，避免位於雙層光罩114 之不透光區111之位置之下的光阻層108照光分解而受到 顯影劑之移除。又，當光阻層108爲負光阻時，則第3圖 中之全透光區110改爲不透光區，第3圖中之不透光區111 改爲全透光區。 雙層光罩114之半透光區112之位置之半透光部分’ 係可降低光源116穿透半透光區112的能量，使位於開口 120處的光阻層108保留一特定厚度，並在後續蝕刻之過 程中，使蝕刻劑先去除殘留於開口 120中的光阻層，再去 除位於保險絲104上方之保護層106,以有效地減少蝕刻 劑對位於保險絲104上方之保護層106之蝕刻量。 經濟部智慧財產局員工消費合作社印製 接著，請參照第4圖所示，利用光阻層1〇8爲罩幕’ 進行過蝕刻步驟，以完全移除位於開口 118底部之保護層 106,暴露出部分銲墊102,以形成銲墊開口 122’其中過 蝕刻之方法包括乾蝕刻法。另外，在過蝕刻之過程中’蝕 刻劑會先去除位於開口 120底部的光阻層1〇8’再去除位 於保險絲104上方之部分保護層1〇6,使保險絲開口 124 7 本紙張尺度適用中國國家標準（CNS)A4規格（210 X 297公釐） 519724 7 2 6 4 twf . doc/006 A7 B7 五、發明說明（έ) (請先閱讀背面之注意事項再填寫本頁) 之底部與保險絲104之間保留有一特定厚度的保護層106， 以防止保險絲104暴露出來，而形成保險絲開口 124其中 位於保險絲開口 124底部至保險絲104之間的保護層106 的厚度，視實際製程之需要而定。 接著，請參照第5圖所示，完全移除光阻層108，以 暴露出保護層106與部分銲墊102，完成銲墊開口 122與 保險絲開口 124，其中移除光阻層、08之方法包括濕式剝 除法或乾式剝除法。 本發明之雙層光罩可在曝光顯影之後，於保險絲之位 置之上仍保留一定厚度之光阻層，以在後續進行蝕刻時， 利用此光阻層作爲蝕刻緩衝區，以減少蝕刻劑對位於保險 絲開口之保護層的蝕刻量，而達到防止蝕刻劑在對銲墊過 蝕刻之時暴露出保險絲的目的，並增加產品良率並降低生 產成本。 另外，本發明之銲墊開口與保險絲開口之形成方法係 使用一次微影蝕刻的方式直接形成銲墊開口與保險絲開 口，與習知之二次微影蝕刻之製程所使用之步驟、時間及 生產成本進行比較，則本發明具有製程步驟較少、製程時 間較短、以及降低生產成本與提高產品良率的優點。 經濟部智慧財產局員工消費合作社印製 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。 8 本紙張尺度適用中國國家標準（CNS)A4規格（210 x 297公釐）519724 7264twf · doc / 006 A7 B7 V. Description of the invention (4) (Please read the precautions on the back before filling this page) Schematic diagram of the method of forming the opening and the fuse opening. Referring to FIG. 1, a metal layer and a metal protective layer (not shown) are sequentially formed on the wafer 100, and then a part of the metal layer and the metal protective layer are removed by using a lithographic etching method to form a solder pad. 102 与 fused 104. The wafer 100 is a semiconductor element with completed metal interconnections. The material of the metal layer includes one of copper and aluminum. The material of the metal protective layer includes one of copper metal oxide and aluminum metal oxide. 'Next, referring to FIG. 2, a passivation layer 106 is formed on the wafer 100. The passivation layer 106 is composed of at least one layer of insulating material, and the material of the insulating material is selected from One of the groups consisting of silicon nitride, oxide, and oxynitride. The method for forming the protective layer 106 includes chemical vapor deposition or physical vapor deposition. Next, a photoresist layer 108 is formed on the protective layer 106. The photoresist layer 108 is a positive photoresist or a negative photoresist. The method of forming the photoresist layer 108 includes using a spin coating method (spm coatmg) to apply a photoresist. Coating on the protective layer 106, and then performing a soft bake process to remove the solvent in the photoresist to form a photoresist layer 108 having a flat surface. Printed by the Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs Next, as shown in Figure 3, perform exposure and development to completely remove the photoresist layer 108 located at the opening 118, expose the protective layer 106, and partially locate the opening The photoresist layer 108 of 120 is removed, so that a certain thickness of the photoresist layer 108 exists between the bottom of the opening 120 and the fuse 104. Here, the photoresist layer 108 is used as a positive photoresistor as an example. The light source 116 is used to expose and develop the photoresist layer 108 through a bi-level mask 114. The double-layer photomask 114 is located above the bonding pad 102. The position is 6 The paper size is applicable to Chinese National Standard (CNS) A4 (210 X 297 mm) 519724 7264twf.d〇c / 006 A7 B7 V. Description of the invention (c) (Please read the precautions on the back before filling (This page) is a fully transparent area 110 so that the light source 116 can be completely penetrated. The developing solution can be used to remove the photoresist layer 108 located at the opening 118, and the protective layer 106 is exposed. The part is a semi-transparent region 112 to partially penetrate the light source 116, and a developing solution can be used to remove a part of the photoresist layer 108 located in the opening 120, and there is a gap between the bottom of the opening 120 and the fuse 104. The photoresist layer 108 has a certain thickness; the non-transparent area 111 is located outside the two positions to completely block the light source 116 from penetrating and avoid being located in the non-transparent area of the double-layered photomask 114 Photoresist layer 108 below 111 And by removing the developer. In addition, when the photoresist layer 108 is a negative photoresist, the fully transparent area 110 in FIG. 3 is changed to an opaque area, and the opaque area 111 in FIG. 3 is changed to a fully transparent area. The semi-transparent part of the position of the semi-transparent area 112 of the double-layered photomask 114 can reduce the energy of the light source 116 penetrating the semi-transparent area 112, so that the photoresist layer 108 at the opening 120 retains a specific thickness, and In the subsequent etching process, the etchant is first removed to remove the photoresist layer remaining in the opening 120, and then the protective layer 106 above the fuse 104 is removed to effectively reduce the etching of the protective layer 106 above the fuse 104 by the etchant. the amount. Printed by the Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs Next, please refer to FIG. 4 and use the photoresist layer 108 as a mask to perform an over-etching step to completely remove the protective layer 106 at the bottom of the opening 118 and expose A part of the bonding pad 102 is formed to form a bonding pad opening 122 ′. The over-etching method includes a dry etching method. In addition, during the over-etching process, the 'etching agent will remove the photoresist layer 108 at the bottom of the opening 120 first, and then remove a part of the protective layer 106 above the fuse 104, so that the fuse opening 124 7 This paper size applies to China National Standard (CNS) A4 specification (210 X 297 mm) 519724 7 2 6 4 twf .doc / 006 A7 B7 V. Description of the invention (hand) (Please read the precautions on the back before filling this page) and the fuse A protective layer 106 with a specific thickness remains between 104 to prevent the fuse 104 from being exposed, and a thickness of the protective layer 106 between the bottom of the fuse opening 124 and the fuse 104 is formed in the fuse opening 124, depending on the actual process requirements. Next, please refer to FIG. 5 to completely remove the photoresist layer 108 to expose the protective layer 106 and a part of the pad 102, and complete the pad opening 122 and the fuse opening 124. The method of removing the photoresist layer 08 Including wet stripping or dry stripping. The double-layered photomask of the present invention can retain a certain thickness of the photoresist layer above the fuse position after exposure and development, so as to use the photoresist layer as an etching buffer during subsequent etching to reduce the etchant The etching amount of the protective layer located at the fuse opening achieves the purpose of preventing the etchant from exposing the fuse when the solder pad is over-etched, and increases the product yield and reduces the production cost. In addition, the method for forming the pad opening and the fuse opening of the present invention is to directly form the pad opening and the fuse opening by using a lithographic etching method, and the steps, time and production costs used in the conventional secondary lithographic etching process. By comparison, the present invention has the advantages of fewer process steps, shorter process time, and reduced production costs and improved product yield. Printed by the Consumer Cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs. Although the present invention has been disclosed as above with a preferred embodiment, it is not intended to limit the present invention. Can make various changes and retouching. 8 This paper size applies to China National Standard (CNS) A4 (210 x 297 mm)