44286 5 經濟部智慧財產局員工消費合作社印製 B7 五、發明說明（/ ) 發明領域： 本發明是有關一種積體電路之金屬蝕刻製程，特別是一 種可以有效去除金屬銲墊或金屬線側壁上的高分子殘留物 的製程方法。 發明背景： 按，在銅製程的發展尚未成熟之前’金屬鋁（鋁銅合金 或鋁矽鋼合金）仍是目前半導體製程中最被廣泛使用的導 體材料，用以做為元件之間的導線。在金屬鋁的餘刻製程 中’通常使用氣化物如Sicu、BC11、ecu等氣體與氣氣cl2 的混合，來進行金屬鋁的RIE餘刻，氣原子和金屬鋁化合生 成二氣化紹氣體（AICI1) ’然後被乾钱刻設備裡的真空系 統抽離。 惟’當鋁合金經過氣化物的電漿蝕刻之後，金屬的表面 及側壁會殘留有氣以及未被真空系統所抽離的三氣化鋁。 假如沒有將這些殘留物去除乾淨，當晶片從乾蝕刻反應器 裡取出之後，空氣中的水分子將與這些殘留的氣或是氯化 物反應，而生成氣化氫(HC1)。這些在鋁合金表面因為空氣 中的水分子所形成的氯化氫將與鋁和銅形成八1(：13和 CuC〗2 ’然後這層AICI1會再與水分子繼續以上所述的循環， 而使铭合金發生腐餘(Corrosion)。 為了避免上述鋁合金的腐餘現象，目前業界廣泛的作 法，是在鋁合金的氣化物電漿的姓刻製程中，加入含氟的 電漿例如CF4或CHF1，使鋁合金表面殘留的氯化物被氟化物 所取代’例如S. Wolf 在Silicon Processing for the VLSI Era, ----------i--------訂· <浼先閱讀會面之注意事項再填寫本頁) 1 l紙張尺度適用中關家標準（CNS)A4規格（210 x 297公髮) 2 442865 A7 B7 經濟部智慧財產局員工消費合作社印製 五、發明說明（J ) Vol. 1 Ch.15—書中所述’其仍將於金屬銲墊或金屬線側壁 上覆蓋一層高分子薄膜。 然，當後續在同一反應腔中利用氧離子灰化法(In-Situ Oxygen Ashing)進行光阻層去除時，並無法將所述殘餘的高 分子完全去除，其原因在於習知之氧離子灰化法係利用氧 氣為反應氣體，使其在高溫中與光阻反應以將所述光阻移 除’然而此反應係為一燃燒放熱反應，是以反應過程中腔 體中溫度很高，將使得所述金屬銲墊或金屬線侧壁上之高 分子殘留物硬化，因而導致該硬化之高分子殘留物不易被 移除。而該殘留物的存在將隨著晶片與水氣(Moisture)的接 觸增加或長的等待時間(Long Q-time)(例如因為客戶的要 求或是碰到大停電而停機）’金屬腐餘的機率便相對提高， 谷易產生電致遷移、短路等問題，並降低元件之可靠度。 故本發明係針對此一殘留不易移除之問題提出解決的 方法，用以有效去除該金屬銲墊或金屬線側壁上的高分子 殘留物。 發明之概述： 本發明之主要目的疋提供一種積體電路之金屬餘刻製 程方法。 本發明的另一目的是提供一種有效移除積體電路之金 屬銲墊或金屬線蝕刻製程中產生之高分子殘留物的製程方 法 本發明係使用下列步驟來達到上述之各項目的：首先，44286 5 Printed by the Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs B7 5. Description of the invention (/) Field of the invention: The present invention relates to a metal etching process for integrated circuits, in particular, it can effectively remove metal pads or metal wire sidewalls. Process method for polymer residues. Background of the Invention: Before the development of the copper process was mature, metallic aluminum (aluminum-copper alloy or aluminum-silicon steel alloy) was still the most widely used conductor material in the current semiconductor manufacturing process, and was used as the conductor between components. In the remaining process of metal aluminum, a gaseous gas such as Sicu, BC11, and ecu is usually mixed with gas gas cl2 to perform the RIE etching of metal aluminum. The gas atoms and metal aluminum are combined to form a two-gas gas ( AICI1) 'Then it was evacuated by the vacuum system in the money engraving equipment. However, after the plasma etching of the aluminum alloy by gas, the metal surface and the side walls will have gas and aluminum tri-gas that has not been removed by the vacuum system. If these residues are not removed cleanly, after the wafer is taken out of the dry etching reactor, water molecules in the air will react with these residual gases or chlorides to form hydrogen gas (HC1). The hydrogen chloride formed by water molecules in the air on the surface of the aluminum alloy will form eight 1 (: 13 and CuC 2) with aluminum and copper. Then this layer of AICI1 will continue the cycle described above with the water molecules, making the alloy Corrosion occurs. In order to avoid the above-mentioned phenomenon of aluminum alloy corrosion, the current widespread practice in the industry is to add a fluorine-containing plasma such as CF4 or CHF1 to the surname engraving process of the aluminum alloy vaporized plasma. Residual chlorides on the surface of aluminum alloys are replaced by fluorides. For example, S. Wolf in Silicon Processing for the VLSI Era, ---------- i -------- Order Read the notes for the meeting and fill in this page) 1 l The paper size applies the Zhongguanjia Standard (CNS) A4 specification (210 x 297) 2 442865 A7 B7 Printed by the Consumer Cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs J) Vol. 1 Ch.15—As described in the book, 'It will still be covered with a polymer film on the side wall of the metal pad or wire. However, when the photoresist layer is subsequently removed in the same reaction chamber using the In-Situ Oxygen Ashing method, the residual polymer cannot be completely removed, which is due to the conventional oxygen ion ashing. The law system uses oxygen as the reaction gas to make it react with the photoresist at a high temperature to remove the photoresist. However, this reaction is a combustion exothermic reaction, because the temperature in the cavity during the reaction is very high, which will make The polymer residue on the side wall of the metal pad or the metal wire is hardened, so that the hardened polymer residue cannot be easily removed. The presence of the residue will increase with the contact between the wafer and the moisture (Moisture) or a long waiting time (Long Q-time) (such as shutdown due to customer requirements or a major power outage). The probability is relatively increased, and Gu is prone to problems such as electromigration and short circuits, and reduces the reliability of the component. Therefore, the present invention proposes a method for solving the problem that the residue is not easy to remove, so as to effectively remove the polymer residue on the side wall of the metal pad or the metal wire. SUMMARY OF THE INVENTION: The main object of the present invention is to provide a metal after-cut process method for integrated circuits. Another object of the present invention is to provide a process method for effectively removing polymer residues generated in metal pads or metal wire etching processes of integrated circuits. The present invention uses the following steps to achieve the above-mentioned items: First,
297公釐） (請先閱讀f面之注音$項再填寫本頁) -裝 <llSJI - 442865 經濟部智慧財產局員工消费合作社印製 A7 _____B7______ 五、發明說明（）） 提供一半導體基板，所述基板上係已形成有金屬層結構； 然後，進行金屬銲墊或金屬線的蝕刻製程；接下來即為本 發明之關鍵步驟，其係在完成金屬蝕刻後先不將晶片移出 反應腔，而在同一反應腔中進行移除光阻的步驟，其係利 用水氣（h2o)為反應氣體對晶片進行處理，用以在所述光 阻移除步驟中，能同時有效去除該金屬銲墊或金屬線侧壁 上的高分子殘留物，並且在金屬表面形成一層保護層。 其中H2〇氣體的流量介於250sccm至800sccm之間，最佳 流量為500sccm ;所述H〇2處理之反應時間介於6〇秒至2〇〇 秒之間，最佳反應時間為120秒；反應氣壓介於i〇〇〇mT〇IT 至4000mTorr之間，而最佳壓力係為2000mTorr ; RF電力的 功率介於800瓦至2000瓦之間，最佳功率為1400瓦。 圖式簡要說明： 圖一為本發明實施例中一已形成有金屬層結構之基板剖面 示意圖。 圖一為本發明實施例中完成金屬姓刻製程後之基板剖面示 意圖。 圖號說明： 10-基板 2〇_金屬阻障層 30-金屬層 40-抗反射| 50-光阻層 A-金屬側壁 發明詳細說明： 本發明係揭露一種積體電路之金屬蝕刻製程方法。經過 ______ 4 本紙張又度適財國'5¾準（CNS)A4規格（21G X 297公釐)' --- (請先閱讀赏面之沒意事項再填寫本頁) 裝--------訂--------I . 442865 A7 五、發明說明（ψ ) 本發明所揭露之方法處理之後’係可有效移除積體電路之 金屬銲塾或金屬線蝕刻製程中產生之高分子殘留物，用以 避免金屬線側壁(Metal Sidewall)、金屬銲墊(Bonding Pad)、 和接觸窗孔洞(Contact/ViaHole)可能產生的腐蝕、電致遷移 或短路問題。特別是在晶片經金屬沉積或金屬蝕刻製程之 後等待時間較長的條件之下’利用本發明所揭露之方法亦 可確保不會有腐蝕問題及降低元件可靠度的情形產生。297 mm) (please read the phonetic $ on the f side before filling out this page)-installed < llSJI-442865 printed by the Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs A7 _____B7______ 5. Description of the invention () A metal layer structure has been formed on the substrate; then, an etching process of a metal pad or a metal wire is performed; the next step is a key step of the present invention, which does not move the wafer out of the reaction chamber after completing the metal etching, The photoresist removal step is performed in the same reaction chamber, which uses water gas (h2o) as the reaction gas to process the wafer, so that the metal pad can be effectively removed at the same time in the photoresist removal step. Or polymer residue on the side wall of the metal wire, and a protective layer is formed on the metal surface. The flow rate of H2O gas is between 250 sccm and 800 sccm, and the optimal flow rate is 500 sccm; the reaction time of the H2O treatment is between 60 seconds and 200 seconds, and the optimal reaction time is 120 seconds; The reaction pressure is between 1000 mToIT and 4000 mTorr, and the optimal pressure is 2000 mTorr; the power of RF power is between 800 watts and 2000 watts, and the optimal power is 1400 watts. Brief description of the drawings: FIG. 1 is a schematic cross-sectional view of a substrate having a metal layer structure formed in an embodiment of the present invention. FIG. 1 is a schematic cross-sectional view of a substrate after a metal surname engraving process is completed in an embodiment of the present invention. Description of drawing number: 10-substrate 20-metal barrier layer 30-metal layer 40-anti-reflection | 50-photoresist layer A-metal sidewall Detailed description of the invention: The present invention discloses a metal etching process method for integrated circuits. After ______ 4 This paper is again suitable for the country of wealth '5¾ standard (CNS) A4 size (21G X 297 mm)' --- (Please read the unintentional matter of the reward before filling out this page) Packing ---- ---- Order -------- I. 442865 A7 V. Description of the Invention (ψ) After the method disclosed in the present invention is processed, it is an effective process for removing metal solder or metal wire etching of integrated circuits. The polymer residues generated in the process are used to avoid the problems of metal corrosion, electromigration, or short circuit caused by the metal side walls, metal bonding pads, and contact / via holes. Especially under the condition that the wafer is subjected to a long waiting time after the metal deposition or metal etching process, the method disclosed in the present invention can also ensure that there will be no corrosion problem and a reduction in the reliability of the component.
首先’請參考圖一 ’提供一半導體基板1〇，所述基板1〇 上係已形成有金屬層30結構，而在形成該金屬層3〇前係可 先形成一金屬阻障層（barrier layer) 20 ’在完成所述金屬層 30後則可再形成一抗反射層（antj_reflecti〇niayer) 4〇以利後 續微影蝕刻製程的進行。其中所述金屬層係為一鋁金屬 層、一銘銅合金金屬層或一銘石夕銅合金金屬層；所述金屬 阻障層20係為一鈦金屬層、一氮化鈦層或由兩者堆疊之複 層結構；而所述抗反射層4〇係為一氮化鈦層Q 然後’先形成一光阻層50，再利用微影蝕刻技術對所述 金屬阻障層20、所述金屬層30及所述抗反射金屬層4〇進行 蝕刻，用以形成金屬銲墊或金屬線結構’其中蝕刻時係選 擇利用含氟氣體（例如：CF4或CHF3)的電漿對其進行乾式 钱刻’如圖二所示，而該含氟氣體的流量介於lsccm至 20sccm之間，最佳流量為5sccm ;反應時間介於8〇秒至2〇〇 秒之間’最佳反應時間為110秒；反應氣壓係介於4mToir至 20mTorr之間，最佳壓力為SmTorr ; RF電力的功率介於500 瓦至2000瓦之間’最佳功率為1000瓦。 (議先閲讀'r面之注意事項再填寫本頁) I * 111111 丨訂·！1 — — — - 經濟部智慧財產局員工消費合作社印製 界紙浪尺&通用中國國豕知;準（CNS)A4規格（21〇 X 997公只） 44286 5 A7 B7 五、發明說明（_ί ) ------— 丨--- 丨 -^^. — 1 (請先閲讀臂面之注意事項再填寫本頁) 接下來即為本發明之關鍵步驟’其係在完成金屬蝕刻後 先不將晶片移出银刻機臺之反應腔，直接在同一反應腔中 進行移除所述光阻層50的步驟，其係利用水氣（h2〇)為反 應氣體對晶片進行處理，用以在所述光阻層5〇移除之步驟 中’能同時有效去除該金屬銲墊或金屬線側壁八上的高分子 殘留物’並且在金屬表面形成一層保護層。 其中所述氏0氣體在腔體先分解出氧氣（〇2)，再利用 該氧氣為反應氣體，使其在高溫中與光阻反應以將所述光 阻層50移除，並同時移除所述金屬銲墊或金屬線側壁A上之 高分子殘留物，由於該分解反應為一吸熱反應，故隨著機 臺之真空系統將反應生成之氣體抽離後，新的反應氣體的 注入’分解反應的再次進行係可再次吸取部分熱量，可以 降低基板表面之反應溫度，如此將有助於降低所述金屬銲 墊或金屬線侧壁上之高分子殘留物因腔體中溫度太高而硬 化的程度’而當該高分子殘留物硬度較低時，則可完全被 所述之氧反應移除’並由真空系統將該反應生成物抽離， 用以避免因該殘留物的存在而容易增高金屬腐蝕的機率、 產生電致遷移、短路現象等等的問題。 經濟部智慧財產局員工消費合作社印製 其中，Η；ϊ〇氣體的流量介於250sccm至800sccm之間，最 佳流量為500sccm;所述H〇2處理之反應時間介於60秒至200 秒之間’最佳反應時間為120秒；反應氣壓介於lOOOmTorr 至4000mT〇rr之間，而最佳壓力係為2〇〇〇mTorr;RF電力的 功率介於500瓦至2000瓦之間，最佳功率為1400瓦。 此外，所述H20氣體處理中所生成之〇2氣體可和鋁金屬 ___ 6 本紙浪過用中國國家標準（CNS)A4規格（210 X 297公爱） 442865First, please refer to FIG. 1 to provide a semiconductor substrate 10 on which a metal layer 30 structure has been formed, and a metal barrier layer (a barrier layer) may be formed before the metal layer 30 is formed. ) 20 ′ After the metal layer 30 is completed, an anti-reflection layer (antj_reflectioniayer) 40 may be further formed to facilitate the subsequent lithographic etching process. The metal layer is an aluminum metal layer, a copper alloy metal layer, or a copper alloy metal layer; the metal barrier layer 20 is a titanium metal layer, a titanium nitride layer, or two The multilayer structure is stacked; and the anti-reflection layer 40 is a titanium nitride layer Q, and then a photoresist layer 50 is formed first, and then the metal barrier layer 20, the The metal layer 30 and the anti-reflective metal layer 40 are etched to form a metal pad or a metal wire structure. Among them, the plasma of a fluorine-containing gas (eg, CF4 or CHF3) is selected for dry money during etching. Engraved as shown in Figure 2, and the flow rate of the fluorine-containing gas is between lsccm to 20sccm, and the optimal flow rate is 5sccm; the reaction time is between 80 seconds and 200 seconds, and the optimal reaction time is 110 Seconds; the reaction pressure is between 4mToir and 20mTorr, the best pressure is SmTorr; the power of RF power is between 500 watts and 2000 watts; the optimal power is 1000 watts. (It is recommended that you read the precautions on the r side before filling in this page.) I * 111111 丨 Order! 1 — — —-Intellectual Property Bureau, Ministry of Economic Affairs, Employee Consumer Cooperative Printed Paper Ruler & GM China National Standard; Standard (CNS) A4 (21〇X 997) only 44286 5 A7 B7 V. Description of Invention ( _ί) -------- 丨 --- 丨-^^. — 1 (Please read the precautions on the arm surface before filling out this page) The next step is the key step of the present invention, which is to complete the metal etching Without removing the wafer from the reaction chamber of the silver engraving machine, the step of removing the photoresist layer 50 is performed directly in the same reaction chamber, which uses water gas (h2O) as the reaction gas to process the wafer. In the step of removing the photoresist layer 50, 'the polymer residue on the metal pad or the metal wire sidewall 8 can be effectively removed at the same time' and a protective layer is formed on the metal surface. The 0 gas decomposes oxygen (0) in the cavity first, and then uses the oxygen as a reaction gas to make it react with the photoresist at a high temperature to remove the photoresist layer 50 and remove the photoresist layer 50 at the same time. Because the decomposition reaction of the polymer residue on the metal pad or the side wall A of the metal wire is an endothermic reaction, after the gas generated by the reaction is removed by the vacuum system of the machine, a new reaction gas is injected. The re-decomposition reaction can absorb part of the heat again, which can reduce the reaction temperature on the substrate surface. This will help reduce the polymer residues on the side surfaces of the metal pads or metal wires because the temperature in the cavity is too high. The degree of hardening ', and when the hardness of the polymer residue is low, it can be completely removed by the oxygen reaction' and the reaction product is removed by a vacuum system to avoid the presence of the residue It is easy to increase the probability of metal corrosion, cause electromigration, short circuit, and other problems. Printed by the Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs, where: Η〇 gas flow is between 250sccm to 800sccm, the optimal flow rate is 500sccm; the reaction time of the H2O treatment is between 60 seconds to 200 seconds The best response time is 120 seconds; the reaction pressure is between 1000mTorr and 4000mTrr, and the optimal pressure is 2000mTorr; the power of RF power is between 500W and 2000W, the best The power is 1400 watts. In addition, the 02 gas generated in the H20 gas treatment can be combined with aluminum metal. ___ 6 This paper is used in China National Standard (CNS) A4 specification (210 X 297 public love) 442865
反應而在金屬表面生成—層氧化鋁層（Al2〇3)。此氧化結 層的結構具有防止水氣及氣氣滲入的作用，作為一可抗腐 蝕的保護層，更進一步的保護製作之金屬銲墊或金屬線。 以上所述係利用較佳實施例詳細說明本發明，而非限制 本追加發明的範圍，因此熟知此技藝的人士應能明瞭，適 當而作些微的改變與調整’仍將不失本發明之要義所在， 亦不脫離本追加發明之精神和範圍，故都應視為本發明的 進一步實施狀況。謹請貴審查委員明鑑，並祈惠准，是 所至禱。 (請无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 適 度 尺 張 紙 本 129 X I10 2 /1\ 格 規 IA4 s) N (c 準 標 家The reaction produces a layer of aluminum oxide (Al203) on the metal surface. The structure of this oxidized layer has the function of preventing water and gas from penetrating. As an anti-corrosion protection layer, it further protects the fabricated metal pads or wires. The above description uses the preferred embodiments to explain the present invention in detail, but not to limit the scope of the additional invention. Therefore, those skilled in the art should be able to understand that appropriate and slight changes and adjustments will still not lose the essence of the invention Where it does not depart from the spirit and scope of the additional invention, it should be regarded as the further implementation status of the invention. I would like to ask your reviewers for their clear reference and to pray for your sincere prayer. (Please fill in this page without reading the notes on the back) Printed by the Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs Moderate paper 129 X I10 2/1 \ Standard IA4 s) N (c