經濟部中央標隼局貞工消费合作社印製 A 6 82 〇 7 五、發明説明（（） 本發明是有關於一種護層(Passivation)的製造方法，且 特別是有關於一種護層的製造過程中，保護金屬銲墊之方 法。 當整個積體電路的主要架構完成後，會在積體電路的 表面上形成一層護層，用於保護位於其下方的積體電路。 而形成金屬銲墊之護層比較常見的材料有磷矽玻璃 (PSG )、氮化矽（SiNx )和聚乙醯氨（Polyimide) °其中 磷ΐ夕玻璃因爲含有具備吸氣（Gettering )能力的磷原子， 因此可以有效的減少水氣及鹼金屬離子的滲透，以延長積 體電路的壽命（Lifetime)。命氮化矽的密度極高，且硬 度極強，可以用來抵擋外界采氣及鹼金屬離子的穿透，並 保護元件免於遭受永久的機/4性傷害。聚亞醯胺則有防水 的效果，可以使元件防水。/ 於金屬銲墊上形成護j#之後，進行第一次定義，即塗 佈一層光阻，經曝光與顯^後，在晶片上留下一層圖案化 之光阻層，再以此圖案化之光阻層爲罩幕，蝕刻護層，暴 露出金屬銲墊，完成蝕刻1之後將光阻層去除。然後，進行 * 一道蝕刻後檢視（After EtjLhing Inspection ; AEI)的品管步 驟，若發現有部分區域因|微影蝕刻機的因素，或光罩對不 準而導致蝕刻不足，則必須重作（Rework)此定義步驟，即 必須重新上光阻，並再進行曝光、顯影與蝕刻等步驟。但 因爲第一次定義完成後，暴露出金屬銲墊’若再進行第二 次的定義，則第一次定義後所暴露出的金屬銲墊會被第二 次定義所用的鹼性顯影液侵蝕（Attack)而形成針 -* (請先閲讀背而之注意事項再填筠本買)Printed by the Central Standards Bureau of the Ministry of Economic Affairs, Zhengong Consumer Cooperative A 6 82 〇7 V. Description of the Invention (() The present invention relates to a method for manufacturing a protective layer, and in particular to a manufacturing process for a protective layer Method for protecting metal pads. After the main structure of the entire integrated circuit is completed, a protective layer is formed on the surface of the integrated circuit to protect the integrated circuit below it. The most common materials for the protective layer are phosphosilicate glass (PSG), silicon nitride (SiNx), and polyimide (Polyimide). Among them, phosphonium glass is effective because it contains phosphorus atoms with gettering ability. To reduce the penetration of water vapor and alkali metal ions to extend the life of the integrated circuit (Lifetime). The life density of silicon nitride is extremely high, and the hardness is extremely strong, which can be used to resist outside gas extraction and penetration of alkali metal ions , And protect the component from permanent mechanical / 4 sexual damage. Polyurethane has a waterproof effect, which can make the component waterproof. / After the protection j # is formed on the metal pad, the first definition is to apply Place a layer of photoresist. After exposure and display, leave a patterned photoresist layer on the wafer, and then use this patterned photoresist layer as a mask to etch the protective layer to expose the metal pads and complete the etching. After 1 remove the photoresist layer. Then, carry out * a quality control step of After EtjLhing Inspection (AEI), if some areas are found due to the factors of the | lithographic etching machine or the misalignment of the photomask If the etching is insufficient, you must rework this definition step, that is, you must re-apply the photoresist, and then perform exposure, development, and etching steps. However, after the first definition is completed, the metal pad is exposed. The second definition, the metal pads exposed after the first definition will be attacked by the alkaline developer used in the second definition (Attack) to form needles-* (Please read the precautions below and then (Fill in the copy to buy)
A7 40 16twf. doc/008 "尺度適用中國國家標準(CNS ) ( 2丨0 X297公妨） 經濟部中央標牟局負工消费合作社印製 46 8207 A 7 4016twf.doc/008 __137 五、發明説明（"7 ) (Pitting)，除了將嚴重影響金屬銲墊之外觀外，還會影響 後續打線(Bonding)製程的良率（Yield)。 因此本發明的目的就是在提供一種護層的製造方法， 可以避免金屬銲墊產生針孔的問題，進一步提升打線製程 的良率。 爲達成上述之目的，本發明提出一種護層的製造方 法，提供一基底，於基底上形成圖案化之金屬焊墊，於基 底與金屬焊墊上形成一層磷矽玻璃層與一層氮化矽層，形 .成暴露出金屬焊墊之開口。然後，進行鈾刻後檢視步驟， 如有部分區域蝕刻不完全，則再形成一層共形之頂蓋層。 接著，重新定義開口，以重新暴露出金屬焊墊。 本發明於重新定義開口之前，會形成一層頂蓋層以保 護金屬銲墊，使得金屬銲墊不會有受到定義過程所使用顯 影液的侵蝕而形成針孔。 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1A圖至第圖’其繪示依照本發明一較佳實施 例的一'種護層的製造流程圖。 圖式之標記說明： 100 :基底 112 :金屬層（金屬銲墊） 113 :磷矽玻璃層 4 (請先閱讀背面之注意事項再填寫本頁) -裝· -5 -6 本紙張尺度適用中國國家標準（CNS ) Μ规梢（210Χ2<?7公¢) A7 137 46 820 7 4016i\vf. doc/008 五、發明説明（3) 115 :氮化ΐ夕層 116 :護層 117 ;開口 118 :頂蓋層 實施例 請參照第1Α圖至第1D圖’其繪示依照本發明一較 佳實施例的一種護層的製造流程圖。 首先請參照第1Α圖，提供一已完成半導體元件之基 底100，於基底100上形成一層金屬層，其中金屬層的材 質比如是鋁或鋁合金。包含金屬層以下的積體電路均已完 成，金屬層是金屬內連線中最上層的金屬層。完成金屬層 的定義以形成圖案化之金屬銲墊Π2後，接著在金屬銲墊 112上形成共形的磷矽玻璃層113，其方法比如是常壓化 學氣相沈積法（Atmospheric Pressure Chemical Vapor Deposition; APCVD或電漿加強化學氣相沈積法（Plasma Enhanced Chemical Vapor Deposition ; PECVD)，用以保護 其下方的積體電路，避免與水氣和鹼金屬離子接觸。 接著，在磷矽玻璃層Π3上形成一層較厚的氮化矽層 115，其方法比如是常壓化學氣相沉積法或電漿加強型化 學氣相沉積法，形成由磷矽玻璃層113與氮化矽層115共 同組成的護層116,以便於抵擋外來的水氣 '鹼金屬離子 及機械性的刮傷。 請參照第1B圖，進行第一次定義，例如微影蝕刻法， 以形成開口 117，暴露出金屬銲墊112。接著’進行一道 5 (請先閲讀背面之注意事項#填寫本頁) 、裝. -s 經濟部中央標率局努工消贽合作社印製 本紙張尺度適用中國國家標率{ CNS ) Λ4规格{ 210X297公鋒） 經濟部中央標準局見工消费合作社印掣 46 82〇7A7 40 16twf. Doc / 008 " Standards apply to Chinese National Standards (CNS) (2 丨 0 X297). Printed by the Central Standardization Bureau of the Ministry of Economic Affairs, Consumer Cooperatives 46 8207 A 7 4016twf.doc / 008 __137 V. Invention (&Quot; 7) (Pitting), in addition to seriously affecting the appearance of the metal pad, will also affect the yield of the subsequent bonding process (Yield). Therefore, the object of the present invention is to provide a method for manufacturing a protective layer, which can avoid the problem of pinholes in metal pads and further improve the yield of the wire bonding process. In order to achieve the above object, the present invention provides a method for manufacturing a protective layer, providing a substrate, forming a patterned metal pad on the substrate, forming a layer of phosphosilicate glass and a layer of silicon nitride on the substrate and the metal pad, Shaped to expose the opening of the metal pad. Then, a post-engraving inspection step is performed. If part of the area is not completely etched, a conformal cap layer is formed. Next, redefine the openings to re-expose the metal pads. Before re-defining the opening, the present invention will form a cap layer to protect the metal pads so that the metal pads will not be corroded by the developing solution used in the definition process to form pinholes. 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: FIG. 1A To the figure, it shows a manufacturing flow chart of a kind of protective layer according to a preferred embodiment of the present invention. Explanation of drawing marks: 100: substrate 112: metal layer (metal pad) 113: phosphor-silicon glass layer 4 (Please read the precautions on the back before filling out this page) -Packing · -5 -6 This paper size applies to China National Standard (CNS) M gauge (210 × 2 <? 7 male ¢) A7 137 46 820 7 4016i \ vf. Doc / 008 V. Description of the invention (3) 115: Nitridium oxide layer 116: Protective layer 117; Opening 118 : Please refer to FIG. 1A to FIG. 1D for an embodiment of the cap layer, which illustrates a manufacturing flowchart of a protective layer according to a preferred embodiment of the present invention. First, referring to FIG. 1A, a completed semiconductor device substrate 100 is provided, and a metal layer is formed on the substrate 100. The material of the metal layer is, for example, aluminum or aluminum alloy. The integrated circuits including the metal layer and below have been completed. The metal layer is the uppermost metal layer in the metal interconnect. After the definition of the metal layer is completed to form a patterned metal pad Π2, a conformal phosphosilicate glass layer 113 is then formed on the metal pad 112. The method is, for example, Atmospheric Pressure Chemical Vapor Deposition APCVD or Plasma Enhanced Chemical Vapor Deposition (PECVD), to protect the integrated circuit below it from contact with water vapor and alkali metal ions. Next, on the phosphosilicate glass layer Π3 To form a thicker silicon nitride layer 115, the method is, for example, atmospheric pressure chemical vapor deposition or plasma enhanced chemical vapor deposition, to form a protective layer composed of a phosphorous silicon glass layer 113 and a silicon nitride layer 115. Layer 116 in order to resist foreign water vapor, alkali metal ions and mechanical scratches. Please refer to FIG. 1B for the first definition, such as lithography, to form openings 117 and expose metal pads 112. . Then, proceed to 5 (please read the note on the back #Fill this page first), and install. Standard rate {CNS) 4 specifications {210X297 male front) Central Standards Bureau of the Ministry of Economy
40 1 6twf.d〇c/00S 五、發明説明（士） 蝕刻後檢視的品管步驟。如檢查後沒有發現任何問題，則 完成此金屬銲墊之護層的製造，但由於定義之過程有可能 產生偏差，如光罩上的圖案於微影步驟時沒有準確地轉移 到護層116上、機台控制不正確或抗反射層(Anti-reflection Coating，ARC)處理不當，而經由蝕刻後檢視得知預定蝕 刻之部位並沒有如期地鈾刻去除時，則繼續進行第二次定 義(第1C圖〜第1D圖）步驟。 請參照第1C圖，形成一層共形之頂蓋層U8(Cap Layer)，例如使用電漿加強型化學氣相沉積法，厚度約數 十到數千A，材質例如爲氧化矽（SiOx)，氮化矽（SixNy)或 氮氧化矽（SixOyNz)，用以保護暴露出之金屬銲墊112。 請參照第1D圖，進行第二次定義，重新定義護層116， 例如重新上光阻’再進行曝光、顯影、蝕刻與去光阻等步 驟’使金屬銲墊112再度暴露出。由於進行顯影步驟時， 金屬銲墊112受到一層頂蓋層118之保護，金屬銲墊112 並不會直接接觸顯影液，使得金屬銲墊112不會受到顯影 液的侵蝕而形成針孔。並且，重新定義護層116之步驟會 使金屬銲墊112上所形成的頂蓋層118同時被去除，使得 頂蓋層118完全不會影響到後續之打線製程，又可於第二 次定義時保護金屬銲墊112。 或者，於蝕刻後檢視步驟之後，會先進行一道回火 (Alloy)之過程，使護層之結構更加穩固，再進行如第1C 圖〜第ID圖所示第二次定義步驟。 由上述本發明較佳實施例可知，本發明於第二次定義 {請先閲讀背面之注意事項再填寫本Η ) .一裝_ 訂. 本紙張尺度適用中國國家標準（CNS ) Λ^)规格（210Χ2Ή公淖）. A7 B7 4 0 l 6twf.doc/008 五、發明説明（γ ) 之前，會先形成一層頂蓋層以保護金屬銲墊，再重新進行 定義之步驟，使得金屬銲墊不會有受到第二此定義過程所 使用顯影液的侵蝕而形成針孔。 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。 (請先閲讀背面之注意事項再填寫本頁) 裝· -540 1 6twf.d〇c / 00S V. Description of the Invention (Taxi) Quality control steps inspected after etching. If no problem is found after the inspection, the manufacturing of the protective layer of the metal pad is completed, but there may be deviations due to the defined process. For example, the pattern on the photomask is not accurately transferred to the protective layer 116 during the lithography step. 2. If the machine control is incorrect or the anti-reflection coating (ARC) is not handled properly, and after the etching inspection, it is known that the etched part has not been removed as expected, then the second definition is continued (section Figure 1C ~ Figure 1D) steps. Please refer to Figure 1C to form a conformal cap layer U8 (Cap Layer). For example, using a plasma enhanced chemical vapor deposition method, the thickness is about tens to thousands of A. The material is, for example, silicon oxide (SiOx). Silicon nitride (SixNy) or silicon oxynitride (SixOyNz) is used to protect the exposed metal pads 112. Please refer to FIG. 1D for the second definition and redefine the protective layer 116, for example, re-apply photoresist and then perform steps of exposure, development, etching, and photoresist removal to expose the metal pad 112 again. Since the metal pad 112 is protected by a cap layer 118 during the developing step, the metal pad 112 does not directly contact the developing solution, so that the metal pad 112 is not attacked by the developing solution and forms pinholes. In addition, the step of redefining the protective layer 116 will remove the top cap layer 118 formed on the metal pad 112 at the same time, so that the top cap layer 118 will not affect the subsequent wire bonding process at all, and it can be used for the second definition Protected metal pads 112. Alternatively, after the inspection step after etching, an alloying process is performed first to make the structure of the cover more stable, and then the second definition step is performed as shown in FIG. 1C to FIG. ID. From the above-mentioned preferred embodiments of the present invention, it can be known that the present invention is defined for the second time {please read the notes on the back before filling in this.). One pack _ order. This paper size applies the Chinese National Standard (CNS) ^^) specifications (210 × 2Ή 公 淖). A7 B7 4 0 l 6twf.doc / 008 5. Before the invention (γ), a cap layer will be formed to protect the metal pad, and then the definition step will be redone to make the metal pad not There will be pinholes formed by the erosion of the developer used in the second definition process. 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 decorations without departing from the spirit and scope of the present invention. The scope of protection of the invention shall be determined by the scope of the attached patent application. (Please read the precautions on the back before filling out this page)
,-L 經璘部中央標隼局貝工消费合作社印製 本紙银尺度適用中國國家標準（〔呢）八4规格（2丨0父297公始）, -L Printed by the Central Standards Bureau of the Ministry of Economic Affairs, Shellfish Consumer Cooperatives. The silver scale of this paper is applicable to the Chinese national standard ([?) 8-4 specifications (2 丨 0 father 297 male)