經濟部智慧財產局員工消費合作社印製 410433 A7 _____B7___ 五、發明說明（） 發明領域： 本發明係有關於一種半導體製程，特別是關於鎢化 學氣相沉積因晶圓背部壓力警報器造成中斷時之晶圓再生 方法。 發明背景： 當積體電路趨向高積集度發展，晶片表面已無法提 供足夠面積製作所需的内連線時，為了配合電晶體縮小後 所增加的内連線需求，兩層以上的金屬層設計已成為許多 積體電路採用的方式，特別是一些較複雜的產品，如微處 理器，甚至需要四層或五層的多層金屬層（multiple metal levels)，才得以完成各元件之間的連接。 鎢金屬已被多數半導體廠商應用於製作多層金屬層 結構中，連接上下金屬層間的中間金屬層，而以金屬鎢所 形成的中間金屬層又稱為鎢插塞（Tungsten Plug)，因鎢 的熔點高，熱膨脹係數與矽相當，且以 CVD法所沉積之 鎢其内應力不高，並具備極佳的階梯覆蓋能力，因此以CVD 法沉積鎢插塞儼然已成為ULSI量產之標準製程之一。 鎢化學氣相沉積（WCVD)方式主要為利用矽將反應氣 體 WF6中之鎮加以還原，又稱為麥還原反應，反應式如 -2- 本紙張尺度適用令國國家標率（CNS)A4規格<210 X 297公釐） ----ώ^-!ιιί. 訂---------線- (請先閱讀背面之注意事項再填寫本頁} 410433 A7 B7 經濟部智慧財產局員工消費合作社印製 五、發明說明（） 下： 2WFe(g) + 3Si(s)——► 2W(s) + 3SiF4(g) 當毯覆性鎢沉積完成之後，再進行一回蝕製程或化學機械 研磨製程’如此即完成一鎮插塞製作。 鎢化學氣相沉積設備有一晶圓背部壓力警報器 (backside pressure alarm, BPA)，該警報器係用於感應 晶圓是否放置於適當處理位置，若晶圓位置不當，則該警 報器啓動並停止該機台之製程，然而，該晶圓若未經適當 處理即重新進行鎢沉積製程，最後通常只有報廢一途。此 外，該背部壓力警報器相當靈敏，由於機台不穩定，因此 在WCVD製程中因該警報器中斷造成晶圓報廢之頻率相 當高，平均約每部機台每星期將報廢四片晶圓，如此造成 相當大之成本浪費。 通常製程中止係由於晶圓之定位問題造成製程中止， 故須重新調整該晶圓之定位，然而此步驟無法避免該晶圓 接觸空氣，故該晶圓表面通常會產生氧化矽，一般為避免 該氧化矽層對後績製程有所影響均採用再次沉積該矽晶種 層後進行WCVD。然而，上述再次沉積矽晶種層之步騾卻 也是造成後績鎢回蝕步驟產生鎢插塞嚴重損失之重要原 因，由於鎢回蚀所使用之氣體均對矽具有良好的蝕刻反應 性，若沉積太多矽於鎢插塞下方可能造成反應不完全而殘 留於鎢插塞下方，如此將加速鎢回蝕之反應速率進而造成 本紙張尺度遶用中國國家標準（CNS)A4規格（210 x 297公釐） -ΓΙ—* ^ I I I I Γ I l· I I II 1 > — — — — 111— (請先閱讀背面之注意事碩再填寫本頁} 410433 A7 ---------B7五、發明說明（） 嚴重之鎢插塞損失。 經濟部智慧財產局員工消費合作社印製 上遴逯成日曰圓報廢之主要原因為鎢化學氣相沉積後 之鎢回蝕（etch back)製程經常導致鎢插塞之損失或凹陷， 如第一圖所示。一半導體基材10已完成第一導線層12 之製作及已定義介電層14中之接觸窗，並已完成ΉΝ黏 著層16與矽晶種層之沉積，進入wcvD反應室後因ΒΡ卢 而中止製程，待重新定位該晶圓後繼績進行後續之wcvc 製程，然而在進行鎢回蝕製程時卻產生嚴重鎢插塞18損 失，使得其無法通過電性檢測，由於此類晶 救製程不易而遭報廢，大幅增加製程成本之浪費。因此， 有必要發展出-種晶圓再造的方法，以改善上迷問題所造 本浪費。目前尚未發展任何晶圓再造方法並可確保 鎢插塞填充狀況艮好，本發明所提出之晶圓再造方 成改善上述傳統製程之缺點。 ' 70 發明目的及概述： 、，本發明之.目的為提供一種出現異常狀況晶圓之再生 方法’以避免該晶圓報廢而造成成本浪費。 本發明之另一目的為提供—種鎢插塞製作方法，以 防止鎢插塞因回蝕過度產生損失。 .4- 本纸張尺度適用中國國家標準（CNS)A4規格（210x297公爱） (請先閱讀背面之注意事項再填寫本頁) - ^^1 ft u HI 一OJ* It 1^1 I ·Printed by the Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs 410433 A7 _____B7___ V. Description of the invention () Field of the invention: The present invention relates to a semiconductor process, especially when tungsten chemical vapor deposition is interrupted due to a wafer back pressure alarm. Wafer recycling method. Background of the Invention: When integrated circuits tend to develop with a high degree of integration and the surface of the chip can no longer provide sufficient area for the interconnections required for fabrication, in order to meet the increased interconnection requirements after the transistor has shrunk, there are more than two metal layers. Design has become the method adopted by many integrated circuits, especially some more complex products, such as microprocessors, and even requires four or five layers of multiple metal levels to complete the connection between components. . Tungsten metal has been used by most semiconductor manufacturers to make multilayer metal layer structures, connecting the intermediate metal layer between the upper and lower metal layers, and the intermediate metal layer formed by metal tungsten is also called a tungsten plug (Tungsten Plug), because of the melting point of tungsten High, thermal expansion coefficient is comparable to silicon, and tungsten deposited by CVD method has low internal stress and excellent step coverage. Therefore, the deposition of tungsten plugs by CVD method has become one of the standard processes for ULSI mass production. . The tungsten chemical vapor deposition (WCVD) method mainly uses silicon to reduce the town in the reaction gas WF6, also known as the wheat reduction reaction. The reaction formula is -2-. This paper is applicable to the national standard rate (CNS) A4 specification. < 210 X 297 mm) ---- ώ ^-! ιιί. Order --------- line- (Please read the notes on the back before filling this page} 410433 A7 B7 Intellectual Property of the Ministry of Economic Affairs Printed by the Bureau ’s Consumer Cooperatives V. Description of the invention () Below: 2WFe (g) + 3Si (s) —— ► 2W (s) + 3SiF4 (g) After the blanket tungsten deposition is completed, an etch-back process is performed. Or the chemical mechanical polishing process' thus completes the production of a plug. The tungsten chemical vapor deposition equipment has a wafer back pressure alarm (BPA), which is used to sense whether the wafer is placed in a proper process. Position, if the wafer is improperly located, the alarm will start and stop the process of the machine. However, if the wafer is not reprocessed, the tungsten deposition process will be retired, and it will usually only be scrapped. In addition, the back pressure alarm The device is quite sensitive. Because the machine is unstable, In the WCVD process, the frequency of wafer scrapping due to the interruption of this alarm is quite high. On average, about four wafers will be scrapped per machine per week, which causes a considerable cost waste. Usually the process suspension is due to wafer positioning problems. As a result of the process suspension, it is necessary to readjust the positioning of the wafer. However, this step cannot prevent the wafer from contacting the air, so silicon oxide is usually generated on the wafer surface. Generally, the silicon oxide layer will not affect the later performance process. The WCVD is performed after the silicon seed layer is deposited again. However, the above step of re-depositing the silicon seed layer is also an important reason for the serious loss of tungsten plugs in the subsequent tungsten etch-back step. All gases have good etching reactivity to silicon. If too much silicon is deposited under the tungsten plug, the reaction may be incomplete and remain under the tungsten plug. This will accelerate the reaction rate of tungsten etchback and cause the paper to scale around. Use Chinese National Standard (CNS) A4 specification (210 x 297 mm) -ΓΙ— * ^ IIII Γ I l · II II 1 > — — — — 111— (Please read the back first Please pay attention to the matter and fill in this page again} 410433 A7 --------- B7 V. Description of the invention () Severe tungsten plug loss. The main reason for the circular scrap is that the tungsten etch back process after tungsten chemical vapor deposition often results in the loss or depression of the tungsten plug, as shown in the first figure. A semiconductor substrate 10 has completed the first wire layer 12 The production and definition of the contact window in the dielectric layer 14, and the deposition of the ΉN adhesive layer 16 and the silicon seed layer have been completed. After entering the wcvD reaction chamber, the process was stopped due to the BPP lu. The subsequent wcvc process, however, caused a serious loss of tungsten plug 18 during the tungsten etch-back process, making it unable to pass the electrical test. This type of crystal salvage process was not easy to be scrapped, which significantly increased the waste of process costs. Therefore, it is necessary to develop a method for wafer remanufacturing to improve the waste caused by the problem. At present, no wafer re-engineering method has been developed and the tungsten plug filling condition can be ensured. The wafer re-engineering method proposed by the present invention can improve the disadvantages of the conventional process. '70 Purpose and Summary of the Invention: The purpose of the present invention is to provide a method for regenerating wafers with abnormal conditions' to avoid the waste of the wafer caused by waste. Another object of the present invention is to provide a tungsten plug manufacturing method to prevent the tungsten plug from being lost due to excessive etch back. .4- This paper size applies to China National Standard (CNS) A4 (210x297 public love) (Please read the precautions on the back before filling this page)-^^ 1 ft u HI-OJ * It 1 ^ 1 I ·
I 410433 經濟部智慧財產局員工消費合作社印製 A7 B7 _ 五、發明說明（） 本發明應用於鎢化學氣相沉積製程中斷後之晶圓再 生方法包含下列步騾：首先提供一晶圓，該晶圓係於製作 鎢插塞之鎢化學氣相沉積製程（WCVD)中因晶圓背部壓力 警報器（backside pressure alarm，BPA)感應而中斷製程， 此時該晶圓表面已覆蓋一層 WCVD之矽晶種層（silicon seed layer)，因此於該晶圓表面執行一满；擊蚀刹 (sputtering etch)製程，將該砍晶種層及少許TiN黏著層 (glue layer)蚀刻掉，隨後再沉積少許新的 TiN黏著層， 並重新進行製作鎢插塞之鎢化學氣相沉積製程，再回蝕該 鎢層以形成鎢插塞於連結洞内。 圖式簡單説明： 第一圖顯示出現異常狀況之半導體基材於傳統插塞 製程後，回蚀製程產生材質損失之截面示意圖。 第二圖顯示本發明中所使用之半導體基材，其出現 異常狀況時之結構截面示意圖。 第三圖顯示本發明中利用濺擊方式回蝕該晶圓至黏 著層之截面示意圖。 第四圖顯示本發明中重新沉積黏著層與矽晶種層於 該晶圓上之截面示意圖。 第五圖顯示本發明中進行鎢化學氣相沉積於該黏著 層上之截面示意圖。 第六圖顯示本發明中進行鎢回蝕製程以形成鎢插塞 -5- 本紙張尺度適用中國國家標準（CNS)A4規格（210 X 297公釐） (請先閲讀背面之ii.意事項再填寫本買)I 410433 Printed by the Consumers ’Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs A7 B7 _ V. Description of the invention () The method for regenerating the wafer after the tungsten chemical vapor deposition process is interrupted includes the following steps: First, a wafer is provided. The wafer was interrupted by the backside pressure alarm (BPA) induction in the tungsten chemical vapor deposition (WCVD) process for making tungsten plugs. At this time, the surface of the wafer was covered with a layer of WCVD silicon. A seed layer is performed on the surface of the wafer; a sputtering etch process is performed to etch away the seed layer and a little TiN glue layer, and then deposit a little more The new TiN adhesion layer is again subjected to the tungsten chemical vapor deposition process for making tungsten plugs, and the tungsten layer is etched back to form tungsten plugs in the connection holes. Brief description of the drawings: The first figure shows a schematic cross-sectional view of the material loss caused by the etch-back process of a semiconductor substrate with an abnormal condition after the conventional plug process. The second figure shows a schematic structural cross-sectional view of a semiconductor substrate used in the present invention when an abnormal condition occurs. The third figure shows a schematic cross-sectional view of the wafer etched back to the adhesion layer by a sputtering method in the present invention. The fourth figure shows a schematic cross-sectional view of the redeposition of the adhesion layer and the silicon seed layer on the wafer in the present invention. The fifth figure shows a schematic cross-sectional view of tungsten chemical vapor deposition on the adhesive layer in the present invention. The sixth figure shows the tungsten etch-back process in the present invention to form tungsten plugs. -5- The paper size is applicable to the Chinese National Standard (CNS) A4 specification (210 X 297 mm) (please read the ii. Intentions on the back first) (Fill in this buy)
410433 A7 B7 五、發明說明（） 於連結洞内之截面示意圖 發明詳細説明： 本發明提供一種鎢化學氣相沉積製程中斷 生方法，係將該晶圓於進行後續製程前利用 < 晶囫π (sputtering etch)回蝕該晶圓表面至黏著層，崦擊蝕刻 黏著層（glue丨ayer)及欲進行鎢化學氣相沉積之重新淀積 (silicon seed layer)，隨即執行鎢化學氣相晶種層 l製程以製 再 作鎢插塞，然後再進行鶴回钮即形成一品 ,,質良好 塞，解決傳統製程中，於回蝕時產生嚴重材 < 鸪揞 之問荀， (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 因此該出現異常狀況之晶圓不再因製程中止而報 D 增加製作鎢插塞結構之良率更節省製程成本支出f 首先參考第二圖所示，提供一半導體基材2〇， 導體基材20上方形成已定義之第一導電層22，以及用於 定義連結洞30之介電層24，該連結洞3〇係用於製作插 塞以產生上下層間之電性連接，該第一導電層22可為一 多晶矽層或金屬層。於本實施例中，該半導體基材2〇係 於鎢化學氣相沉積製程（WCVD)中產生異常狀況，如該晶 囷定位有偏移狀況時，可由監測該晶圓背部氣體壓力變 化，判斷出異常狀況，機台之晶圓背部壓力警報器 (backside pressure alarm, BPA)感應異常而中斷，此時 該半導體基材20表面已形成一 TiN黏著層26及一矽晶 不僅 該半 -rll·,----訂---------線、 -6 本紙張尺度適用中國國家標準（CNS)A4規格（210 X 297公釐） A7 B7 410433 五、發明說明（ 種層28,該TjN黏著層26用於增加沉料層與第 層22之附著能力，其厚度_為㈣至1〇〇〇 a，同時作 為稍後回蝕製程之蝕刻終點。兮劢3 而孩梦印種層28則用於與 WF6礼體反應產生鎮沉積’且兮游g稀爲士 凡運尽日日種層28表面最好沒 有氧化珍的產生，因此形成該欲曰赫恳„ β 邊♦时種層28與進行鎢沉積 之間隔時間越短越好，以免影鎏WCN/ri 士 π / w # WGVD疋迦行及製成元 件之良率。 如第三圖所示，説明本發明利用濺擊蝕刻（sputtering etch)法，將上述因定位問題產生製程中止之晶圓表面之 矽晶種層及部分TiNJ黏著層予以蝕刻除去。其中該矽晶種 層將完全蚀刻掉，而TiN黏著層蝕刻厚度約】〇〇A，留下 部分TiN黏著層263,上述濺擊蝕刻步驟所使用之氣體為 氬氣（argon)。 接續請參考第四圖，當上述晶圓予以濺擊蝕刻處理之 後，再利用物理氣相沉積法（PVD)或化學氣相沉積法（CVD) 重新’'儿積TiN黏著層26b，其中上述重新沉積之TjN黏著 層厚度約100A。如此該晶圓表面具有新生的TiN黏著層 26b且厚度與原始製程之ΤΊΝ層厚度相同，且於接續進行 之鎢插塞沉積製程中再形成新的矽晶種層32(不含氧化梦） 供鎢沉積反應之進行，亦不會影響製成元件之效能。 如第五圖所示，説明本發明利用習知鎢化學氣相沉積 本紙張尺度適用中國國家標準（CNS)A4規格（210 X 297公釐） *111.. —/'——I — ^ I I I I I I ! — — — II (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 410433 A7 經濟部智慧財產局員工消费合作社印製 B7 五、發明說明（） 製程作毯覆性金屬鎢沉積，形成一金屬鎢層34於TiN黏 著層26b上方，並形成填充良好之鎢插塞於連結洞30中。 其次，參考的第六圖，利用反應性離子蚀刻法（Reactive Ion Etching, RIE)進行羈回蚀（tungsten etch back)，用於鎮 回蝕之氣體如SFs。本發明所形成之鎢插塞34a具有良好 填充狀況，且無鎢插塞損失之情況發生，因此可進行後續 製程，如沉積第二導電層 36於其上，以製作下一層導體 連線’該第二導電層36可為一多晶矽層或金屬層，而所 製成之元件可通過電性檢測，解決傳統因鎢插塞損失無法 修復而造成晶圓報廢之課題。 综上所述，本發明提供一種鎢化學氣相沉積製程中斷 後避免鎢插塞損失之晶圓再生方法，可防止傳統製程中導 體材質於回蚀時所羞生的材質損失，解決傳統插塞製程中 因異常狀況重新沉積時所導致之問題，形成具有良好接觸 及附著能力的插塞，增加製程的良率及產品的可靠度。 本發明以一較佳實施例說明如上，僅用於藉以幫助了 解本發明之實施，非用以限定本發明之精神，而熟悉此領 域技藝者於領悟本發明之精神後，在不脫離本發明之精神 範圍内’當可作些許更動满飾及等同之變化替換，其專利 保護範圍當視後附之申請專利範圍及其等同領域而定。 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)410433 A7 B7 V. Description of the invention () Cross-section schematic diagram in the connection hole Detailed description of the invention: The present invention provides a method for interrupting the tungsten chemical vapor deposition process, which uses the wafer before subsequent processes < (Sputtering etch) etches back the wafer surface to the adhesive layer, taps the etching adhesive layer and the silicon seed layer for tungsten chemical vapor deposition, and then performs tungsten chemical vapor seeding The layer l process is used to make tungsten plugs, and then the crane back button is formed into a product. The plugs are of good quality, which solves the traditional process of producing serious materials during etchback. <Please read first> (Please read first Note on the back, please fill out this page again.) Printed by the Consumer Cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs. Therefore, wafers with abnormal conditions will no longer be reported due to process suspension. D Increasing the yield of tungsten plug structure will save process cost expenditure f First, referring to the second figure, a semiconductor substrate 20 is provided. A defined first conductive layer 22 is formed above the conductive substrate 20, and a dielectric layer 24 for defining a connection hole 30 is provided. 3〇 system for making a plug for electrically connecting between the upper and lower generation of the first conductive layer 22 may be a polysilicon layer or a metal layer. In this embodiment, the semiconductor substrate 20 is abnormal during the tungsten chemical vapor deposition process (WCVD). If the wafer is misaligned, it can be determined by monitoring the change in gas pressure at the back of the wafer. In the abnormal condition, the wafer backside pressure alarm (BPA) of the machine is abnormal and interrupted. At this time, a TiN adhesive layer 26 and a silicon crystal have been formed on the surface of the semiconductor substrate 20. Not only the semi-rll · , ---- Order --------- line, -6 This paper size applies to China National Standard (CNS) A4 specification (210 X 297 mm) A7 B7 410433 V. Description of invention (seed layer 28, The TjN adhesive layer 26 is used to increase the adhesion between the sinker layer and the second layer 22, and its thickness is ㈣ to 1000a, and at the same time, it is used as the etching end point of the etch-back process later. The layer 28 is used to react with the WF6 etiquette to produce ballast deposits, and it is rare that the surface of the seed layer 28 should not be oxidized. Therefore, the formation of this desire is very important. The shorter the interval between the seed layer 28 and the tungsten deposition, the better, so as not to affect the WCN / ri π / w # WGVD 疋The yield rate of the component and the finished component. As shown in the third figure, the present invention uses a sputtering etch method to explain the silicon seed layer and a portion of TiNJ on the wafer surface where the process is stopped due to the positioning problem. The adhesive layer is etched away. The silicon seed layer will be completely etched away, and the TiN adhesive layer will be etched to a thickness of about OOA, leaving a portion of the TiN adhesive layer 263. The gas used in the above-mentioned sputtering etching step is argon ( argon). Please refer to the next figure, after the wafer is subjected to sputtering etching, the physical vapor deposition method (PVD) or chemical vapor deposition method (CVD) is used to rebuild the TiN adhesive layer 26b. The thickness of the re-deposited TjN adhesive layer is about 100 A. In this way, the wafer surface has a new TiN adhesive layer 26b and the thickness is the same as that of the original TZO layer, and a new one is formed in the subsequent tungsten plug deposition process. The silicon seed layer 32 (excluding the oxide dream) is used for the tungsten deposition reaction, and it will not affect the performance of the fabricated component. As shown in the fifth figure, the present invention illustrates the use of conventional tungsten chemical vapor deposition on this paper. Use Chinese National Standard (CNS) A4 specification (210 X 297 mm) * 111 .. — / '—— I — ^ IIIIII! — — — II (Please read the notes on the back before filling this page) Wisdom of the Ministry of Economic Affairs Printed by the Consumer Cooperative of the Property Bureau 410433 A7 Printed by the Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economics Printed B7 V. Description of the invention () The process is to deposit blanket metal tungsten to form a metal tungsten layer 34 above the TiN adhesive layer 26b and form The well-filled tungsten plug is in the connection hole 30. Secondly, referring to the sixth figure, the reactive ion etching method (Reactive Ion Etching, RIE) is used to carry out tungsten etch back, which is used to suppress the gas such as SFs. The tungsten plug 34a formed by the present invention has a good filling condition, and no tungsten plug loss occurs, so subsequent processes can be performed, such as depositing a second conductive layer 36 thereon to make the next layer of conductor wiring. The second conductive layer 36 can be a polycrystalline silicon layer or a metal layer, and the fabricated component can pass the electrical test, which solves the conventional problem of wafer scrap due to the loss of tungsten plugs that cannot be repaired. To sum up, the present invention provides a wafer regeneration method for avoiding the loss of tungsten plugs after the tungsten chemical vapor deposition process is interrupted, which can prevent the loss of material caused by the conductor material during etch back in the traditional process, and solve the traditional plugs. Problems caused by redeposition in the process due to abnormal conditions, forming plugs with good contact and adhesion capabilities, increasing the yield of the process and the reliability of the product. The present invention is described above with a preferred embodiment, and is only used to help understand the implementation of the present invention, and is not intended to limit the spirit of the present invention. Those skilled in the art will not depart from the present invention after understanding the spirit of the present invention. Within the scope of the spirit ', some modifications and equivalent changes can be made, and the scope of patent protection depends on the scope of the attached patent application and its equivalent fields. This paper size applies to China National Standard (CNS) A4 (210 X 297 mm) (Please read the precautions on the back before filling this page)
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