1241644 14505twf.doc/g 九、發明說明： 【發明所屬之技術領域】 本發明是有關於一種半導體製程，且特別是有關於一 種晶圓的清洗方法以及間極結構的製造方法。 【先前技術】 在現今的半V體製私中，晶圓清洗是頻繁且重要的步 驟之一。洗淨的目的主要是用來清除晶圓表面的殘留物， • 如微粒(Particle)、有機物(0rSanic)和無機物金屬離子(Metai Ions)等。因此，晶圓洗淨技術是影響製程良率(Yidd)、元 件品質及可靠度的重要因素之一。 另一方面，閘極結構的製作是半導體製 的 • 綱之-，且其品質亦影響著製程良率、元: 靠度等。因此，如何在製作閘極結構的過程中，使晶圓達 到高潔淨度的要求以製作出品質良好的閘極肖構是值得重 視的問題。 在習知技術中，對於一具有高介電常數(high_K)之間 攀介電層的閘極結構來說，其製造方法係先提供一基底，且 於此基底上依序形成具有高介電常數之閘介電層、氮化鈦 阻障層與多晶矽閘極層。之後，對這些膜 ， 形成一閘極結構。然後，使用氫氟酸(HF')、氫氟酸與過氧 化氫之混合溶液(HF/H2〇2)或者含氟的有機溶劑等來清洗 基底表面的殘留物。 然而，在定義閘極結構的過程中，除了會產生一些微 粒或污染物之外，被移除的多晶矽閘極層與氮化鈦阻障層 1241644 14505twf.doc/g 的殘留物還可能會反應生成氮化矽殘留物，並且落在閘介 電層的表面上。如此當在定義閘介電層時，這些氮化矽殘 留物會成為閘介電層之部分區域的罩幕，以致於被遮蓋的 區域無法蝕刻完全，而留下閘介電層的殘留物。值得注意 的疋，在對基底利用上述之清洗液進行清洗，這些閘介電 層的殘留物上因其覆蓋有氮化矽殘留物，因此仍無法除 去:圖3是利用掃瞄式電子顯微鏡(SEM)所拍攝之照片圖， • 其為在閘極結構定義並進行清洗之後所得之部分晶圓的照 片圖。在圖3中可以發現有許多白點，其為殘留於晶圓上 的殘留物301。也就是說，經過清洗之後，氮化矽殘留物 及閘介電層的殘留物依然存在。如此一來，這些在晶圓表 • 面上的殘留物，將會對元件品質及可靠度產生不利的影響。 【發明内容】 θ 有鑑於此，本發明的目的就是在提供一種晶圓的清诜 方法，以去除晶圓表面的殘留物，提高晶圓之製程良率。 本發明的再一目的是提供一種閘極結構的製造方法， 以在製作閘極結構的過程中，有效去除晶圓表面的殘留 物’進而提升元件品質及可靠度。 基於上述與其它目的，本發明提出一種晶圓的清洗方 法，此方法係適於定義出閘極結構之後。其中，此閘極結 構從基底表面由下而上依序為閘介電層、含氮的阻障層與 含石夕的閘極層。而本發明之清洗方法係使用磷酸溶液與氫 氟酸溶液對基底進行清洗。 本發明再提出一種閘極結構的製造方法，其係先於一 1241644 14505twf.doc/g if上形=介電層於此閘介電層上形成含氮的阻 ^層，後再於此含氮的阻障層上形成切的閘極層。接 著疋義上，之含石夕的閘極層、含氮的阻障層與問介電層 以形^ - 結構’以及使用顧溶液與氫氟酸溶液對基 底進彳丁清洗步驟。 依照本發明之較佳實施例所述，在上述晶圓的清洗方 賴’結構的製造方法中，其清洗方法係使用碟酸溶液 與虱氟酸溶液混合所得之混合溶液，或是依序使_酸溶 液與氫氟酸浴液，又或者是依序使用氫氟酸驗、鱗酸溶 液與^酸溶液縣錢行清洗。其巾，在氫氟酸溶液中， 水與氫氟酸之混合比例係約介於10⑻：丨到1〇〇〇〇:1之間。 此外，磷酸溶液的溫度約為攝氏160度。另外，上述之閘 介電層的材質例如是具有高介電常數之材料。其中，前述 之材料例如是氧化铪(Hf〇2)、摻有氮的氧化铪、摻有氮與 矽的氧化铪或摻有矽的氧化铪。此外，此閘介電層的形成 方法例如是進行原子層沈積製程（Atomic Layer Deposition，ALD)或金屬有機化學氣相沈積製程(Metai1241644 14505twf.doc / g IX. Description of the invention: [Technical field to which the invention belongs] The present invention relates to a semiconductor process, and particularly to a method for cleaning a wafer and a method for manufacturing an interelectrode structure. [Previous technology] In today's semi-V systems, wafer cleaning is one of the frequent and important steps. The purpose of cleaning is mainly to remove residues on the wafer surface, such as particles, organics (OrSanic), and inorganic metal ions (Metai Ions). Therefore, wafer cleaning technology is one of the important factors that affects the process yield (Yidd), component quality, and reliability. On the other hand, the fabrication of the gate structure is semiconductor-based, and its quality also affects the process yield, reliability, and reliability. Therefore, in the process of fabricating the gate structure, how to make the wafer meet the requirements of high cleanliness to make a good gate structure is a question worthy of attention. In the conventional technology, for a gate structure having a dielectric layer with a high dielectric constant (high_K), a manufacturing method is to first provide a substrate, and sequentially form a substrate with high dielectric on the substrate. Constant gate dielectric layer, titanium nitride barrier layer and polycrystalline silicon gate layer. Then, a gate structure is formed on these films. Then, the residue on the surface of the substrate is washed with hydrofluoric acid (HF '), a mixed solution of hydrofluoric acid and hydrogen peroxide (HF / H202), or an organic solvent containing fluorine. However, in the process of defining the gate structure, in addition to generating some particles or pollutants, the residue of the removed polycrystalline silicon gate layer and the titanium nitride barrier layer 1241644 14505twf.doc / g may also react. A silicon nitride residue is formed and falls on the surface of the gate dielectric layer. So when defining the gate dielectric layer, these silicon nitride residues will become a mask for a part of the gate dielectric layer, so that the covered area cannot be etched completely, leaving a residue of the gate dielectric layer. It is worth noting that when the substrate is cleaned with the above-mentioned cleaning solution, the residues of these gate dielectric layers cannot be removed because they are covered with silicon nitride residues: Figure 3 is a scanning electron microscope ( SEM) Photographs: • Photographs of part of the wafer obtained after gate structure definition and cleaning. Many white spots can be found in Fig. 3, which are residues 301 remaining on the wafer. In other words, after cleaning, the silicon nitride residue and the residue of the gate dielectric layer still exist. As a result, these residues on the wafer surface will adversely affect component quality and reliability. [Summary of the Invention] θ In view of this, the object of the present invention is to provide a method for cleaning wafers to remove residues on the surface of the wafer and improve the yield of the wafer process. It is still another object of the present invention to provide a method for manufacturing a gate structure, so as to effectively remove residues on the surface of the wafer 'during the fabrication of the gate structure, thereby improving the quality and reliability of the device. Based on the above and other objectives, the present invention proposes a wafer cleaning method, which is suitable after defining the gate structure. The gate structure is a gate dielectric layer, a nitrogen-containing barrier layer, and a stone-containing gate layer in this order from bottom to top of the substrate surface. The cleaning method of the present invention uses a phosphoric acid solution and a hydrofluoric acid solution to clean the substrate. The present invention further proposes a method for manufacturing a gate structure, which is a 1241644 14505twf.doc / g if shape = dielectric layer forms a nitrogen-containing barrier layer on the gate dielectric layer, and then contains A cut gate layer is formed on the nitrogen barrier layer. Next, the gate layer containing Shi Xi, the nitrogen-containing barrier layer and the interlayer dielectric layer are shaped as a structure, and the substrate is subjected to a cleaning step using a sol solution and a hydrofluoric acid solution. According to a preferred embodiment of the present invention, in the method for manufacturing a wafer cleaning structure described above, the cleaning method is a mixed solution obtained by mixing a dish acid solution and a fluoric acid solution, or sequentially using _Acid solution and hydrofluoric acid bath, or use the hydrofluoric acid test, the scale acid solution and the acid solution in order to clean. In the towel, the mixing ratio of water and hydrofluoric acid in the hydrofluoric acid solution is between about 10 ⑻: 10000: 1. In addition, the temperature of the phosphoric acid solution is about 160 degrees Celsius. The material of the gate dielectric layer is, for example, a material having a high dielectric constant. Among them, the aforementioned materials are, for example, hafnium oxide (Hf02), hafnium oxide doped with nitrogen, hafnium oxide doped with nitrogen and silicon, or hafnium oxide doped with silicon. In addition, the method for forming the gate dielectric layer is, for example, an atomic layer deposition (ALD) process or a metal organic chemical vapor deposition process (Metai).
Organic Chemical Vapor Deposition，MOCVD)。另外，含 氮的阻P羊層之材質例如是氮化鈦，以及含石夕的閘極層之材 質例如是多晶矽或摻雜多晶矽。 由於本發明之清洗方法係使用構酸溶液與氫氟酸溶液 對基底進行清洗，特別是，磷酸溶液可有效去除由含氮的 阻障層與含矽的閘極層所生成之氮化矽殘留物。因此，可 以解決習知因氮化矽殘留物無法去除，而導致在其下方的 1241644 14505twf.doc/g 閘介電層之殘留物無法完全清除的問題。如此一來，便有 助於提昇晶圓之製程良率、元件品質及可靠度。 為讓本發明之上述和其他目的、特徵和優點能更明顯 易酸’下文特舉較佳實施例，並配合所附圖式，作詳細說 明如下。 【實施方式】 圖1A到圖id是繪示依照本發明之較佳實施例的一種Organic Chemical Vapor Deposition (MOCVD). In addition, the material of the nitrogen-containing P resist layer is, for example, titanium nitride, and the material of the gate layer containing stone is, for example, polycrystalline silicon or doped polycrystalline silicon. Since the cleaning method of the present invention uses a structuring acid solution and a hydrofluoric acid solution to clean the substrate, in particular, the phosphoric acid solution can effectively remove the silicon nitride residue generated from the nitrogen-containing barrier layer and the silicon-containing gate layer. Thing. Therefore, it is possible to solve the conventional problem that the residue of the silicon dielectric layer under the 1231644 14505twf.doc / g gate dielectric layer cannot be completely removed because the silicon nitride residue cannot be removed. In this way, it will help improve the process yield, component quality and reliability of the wafer. In order to make the above and other objects, features, and advantages of the present invention more obvious, the preferred embodiment will be described in detail below with reference to the accompanying drawings. [Embodiment] FIGS. 1A to 1D are diagrams illustrating a method according to a preferred embodiment of the present invention.
閘極結構之製造流程剖面示意圖。圖2是繪示圖1A到圖 1D之步驟流程圖。 凊同時參照圖1A與圖2,首先，於基底100上形成閘 ;丨電層102(步驟200)。其中，閘介電層1〇2的材質例如是 ^有高介電常數之材料，其例如是氧化铪、摻有氮的氧化 給、摻有氮與㈣氧化铪、摻有賴氧麟或是其他合適 之材料。此夕卜間介電的形成方法例如是進行原子 f沈積製程、金射機化學氣相沈積製程或是其他合適之 接者 ;黾層1〇2上形成含氮的阻障層104(步驟 含氦的阻障層104之材質例如是氮化鈦或是其他 &適之线的材料，而其形成方 ^(Chemical Vapor Depositi〇n, CVD^； J s ； 或是其他合叙製程。 VD)赠(SP_nng) ，步之含Λ的阻障層104上形成含石夕的間極層 6卜驟204)。其令’此含石夕的間 多晶梦、穆雜多晶梦或是其他合適之切二 = 卜疋 1241644 14505twf.doc/g ^成方法例如是進行化學氣相沈積製程或是其他合適之 製程。 Μ入^著疋義含石夕的間極層1〇6、含氮的阻障層104與 閘；丨電層102，以形成一® 烕堆&結構(步驟206)，其詳細說明 如下。 月二…、囷疋義含石夕的閘極層1〇6與含氮的阻障層 1—04先形成堆疊結構1G7。錢，如先前技術所提，在 疋義5石夕的閉極層106與含氮的阻障層104之過程中，除 了 ^產生些u粒或污染物之外，被移除之含石夕的問極層 _與含氮的阻障们04的殘留物⑽還可能會反應生成 亂化石夕?留物11。，並且落在閉介電層1〇2的表面上。之 後丄繼縯定義間介電層1〇2以形成堆疊結構1〇9(如圖ic 所示）且此堆豐結構係由上述之堆疊結構與閘介 電層102所構成 '然而，同樣如先前技術所提，由於氮化 =留物110落在閘介電層102的表面上，導致當定義閘 介，==2時，這些氮化矽殘留物11〇會成為閘介電層1〇2 之。卩刀區域的罩幕，以致於罩幕所遮蓋的區域無法钱刻完 全’而留下閘介電層1〇2的殘留物102a。 繼之，請同時參照圖ID與圖2,在堆疊結構1〇9形成 之後，使用磷酸溶液與氫氟酸溶液對基底100進行清洗步 驟(步驟208)，以去除基底100上之殘留物102a、110。其 中’上述之清洗步驟例如是使用雄酸溶液與氫氟酸溶液混 合所得之混合溶液、依序使用氫氟酸溶液、磷酸溶液與氫 默酸溶液或者是依序使用磷酸溶液與氫氟酸溶液來清洗基 9 1241644 14505twf.d〇c/g 一 t 2別疋除了别述之方法外，本發明尚可將鱗酸溶液 2風氣酸溶液以其他不同之使用順序進行清洗，即清洗順 亚不限ft述之清洗方式。此外，在上述之氫氟酸溶液 水與氣氟酸之混合比例係約介於1000 : 1到10000 : 1 之間。另外，磷酸溶液的溫度約為攝氏160度。 X特別值得一提的是，於上述之清洗步驟(步驟208)中使 用％駄’谷液可有效去除由含氮的阻障層104與含矽的閘極 • 層106所生成之氮化石夕殘留物110。換言之，由於氮化石夕 歹欠遠物110可藉由墙酸溶液清洗去除，因此習知因氮化石夕 ^^物110無法去除而導致其下方的間介電層撤之殘留 物l〇2a無法藉由氫氟酸完全清除的問題亦可一併解決。 此外，在上述之清洗步驟(步驟208)之後，利用掃描式 私子顯彳政^(SEM)拍攝部分晶圓所得到之照片圖係如圖4 所不。由圖4可知，相較於先前技術中之照片圖（圖3”原 先在基底100上的白點(殘留物3〇1)已消失。也就是說，利 用本發明的清洗方法清洗晶圓之後，氮化石夕殘留物11〇與 • 閘介電層的殘留物l〇2a可以被完全去除。 ” 綜上所述:士發明之晶圓的清洗方法適於定義出閘極 結構之後，其係藉由使用磷酸溶液與氳氟酸溶液對基底進 行清洗。特別是，習知無法有效去除之氮化石夕殘留物以及 閘介電層的殘留物，可以利用本發明之清洗方法來解決， 如此可提昇晶圓的製程良率、元件品質及可靠度。 雖然本赉明已以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 1241644 14505twf.doc/g 和範圍内，當可作此 範圍當視後~ 13更動與潤飾，因此本發明之保護 =¾請專利範圍所界定者為準。 结構Ξ製：以之較佳實副-種閘極 圖2疋f lA到圖1D之步驟流程圖。Schematic sectional view of the manufacturing process of the gate structure. FIG. 2 is a flowchart showing the steps of FIGS. 1A to 1D.凊 Referring to FIG. 1A and FIG. 2 at the same time, first, a gate is formed on the substrate 100; an electrical layer 102 (step 200). Among them, the material of the gate dielectric layer 102 is, for example, a material having a high dielectric constant, which is, for example, erbium oxide, nitrogen-doped oxidizing agent, nitrogen and erbium-doped holmium oxide, Lai-oxyline, or other Suitable material. In this case, the dielectric formation method is, for example, an atomic f deposition process, a metallographic chemical vapor deposition process, or other suitable connections; a nitrogen-containing barrier layer 104 is formed on the hafnium layer 102 (steps including The material of the barrier layer 104 of helium is, for example, titanium nitride or other suitable materials, and its formation method is (Chemical Vapor Deposition, CVD ^; J s); or other processes. VD ) Donate (SP_nng) to form the interlayer layer containing stone eve on the barrier layer 104 containing Λ (step 204). It makes' this Shima-containing polycrystalline dream, muza polycrystalline dream, or other suitable cuts = 疋 11241644 14505twf.doc / g ^ The formation method is, for example, a chemical vapor deposition process or other suitable Process. The following describes the interlayer layer 106 containing the stone, the nitrogen-containing barrier layer 104, and the gate; the electric layer 102 to form a ® stack & structure (step 206), which is described in detail below. . On February…, Shiyi ’s gate layer 1106 containing nitrogen and barrier layer 1-04 containing nitrogen first form a stacked structure 1G7. Qian, as mentioned in the prior art, in the process of the closed electrode layer 106 and the nitrogen-containing barrier layer 104 of Shiyi 5 Shixi, in addition to generating some u particles or pollutants, the stone-containing Xixi was removed. The interrogation layer _ and the residues 04 of the nitrogen-containing barriers 04 may also react to form chaotic fossils? And land on the surface of the closed dielectric layer 102. Later, I continued to define the interlayer dielectric layer 102 to form a stacked structure 109 (as shown in Figure ic), and this stack structure was composed of the above-mentioned stacked structure and the gate dielectric layer 102. However, the same as As mentioned in the prior art, because the nitride = remnant 110 falls on the surface of the gate dielectric layer 102, when the gate dielectric is defined, == 2, these silicon nitride residues 11 will become the gate dielectric layer 1〇 2 of them. The mask in the area of the trowel is such that the area covered by the mask cannot be completely engraved ', leaving a residue 102a of the gate dielectric layer 102. Next, please refer to FIG. 2 and FIG. 2 simultaneously. After the stacked structure 10 is formed, the substrate 100 is cleaned using a phosphoric acid solution and a hydrofluoric acid solution (step 208) to remove the residues 102a, 110. The above-mentioned cleaning step is, for example, the use of a mixed solution obtained by mixing an androic acid solution and a hydrofluoric acid solution, a sequential use of a hydrofluoric acid solution, a phosphoric acid solution and a hydromer acid solution or a sequential use of a phosphoric acid solution and a hydrofluoric acid solution To clean the base 9 1241644 14505twf.d0c / g-t 2 Don't do anything else. In addition to the other methods, the present invention can also clean the scale acid solution 2 Fengqi acid solution in a different order of use, that is, the cleaning of shunyabu Limit ft described cleaning methods. In addition, in the above hydrofluoric acid solution, the mixing ratio of water and gas hydrofluoric acid is about 1000: 1 to 10000: 1. The temperature of the phosphoric acid solution was about 160 degrees Celsius. X is particularly worth mentioning is that the use of% 駄 'solution in the above-mentioned cleaning step (step 208) can effectively remove the nitride nitride formed by the nitrogen-containing barrier layer 104 and the silicon-containing gate layer 106. Residue 110. In other words, since the nitride nitride material 110 can be removed by washing with a wall acid solution, it is known that the residue 1102a of the interlayer dielectric layer cannot be removed because the nitride material 110 cannot be removed. The problem of complete removal by hydrofluoric acid can also be solved together. In addition, after the above-mentioned cleaning step (step 208), a photograph obtained by scanning a part of the wafer using a scanning private display (SEM) is shown in FIG. 4. It can be seen from FIG. 4 that, compared with the photos in the prior art (FIG. 3), the original white spots (residues 301) on the substrate 100 have disappeared. That is, after the wafer is cleaned by the cleaning method of the present invention The residue of nitride nitride 11 and the residue of gate dielectric layer 10a can be completely removed. "In summary: after the wafer cleaning method of the invention is suitable for defining the gate structure, the system The substrate is cleaned by using a phosphoric acid solution and a hydrofluoric acid solution. In particular, it is known that the residues of nitrided nitride and the residue of the gate dielectric layer that cannot be effectively removed can be solved by using the cleaning method of the present invention. Improve the process yield, component quality and reliability of the wafer. Although the present invention has been disclosed as above with a preferred embodiment, it is not intended to limit the present invention. Anyone skilled in this art will not depart from the spirit of the present invention 1241644 In the range of 14505twf.doc / g and the range, when this range can be regarded as the modification and retouching after ~ 13, the protection of the present invention = ¾ please define the scope of the patent. Structure control: the best practice- Figure 2 疋 f lA Go to the flowchart of steps in FIG. 1D.
圖3為習知進行清洗後，利用掃描式電子顯微鏡(SEM) 所拍攝之照片圖。 圖4為使用本發明之清洗方法後，利用掃描式電子顯 微鏡(SEM)所拍攝之照片圖。 【主要元件符號說明】 100 ·基底 102 ·閘介電層 102a、108、11〇、301 :殘留物 104 :阻障層 106 :閘極層 107、109 :堆疊結構 200、202、204、206、208 :步驟 11FIG. 3 is a photograph taken by a scanning electron microscope (SEM) after conventional cleaning. Fig. 4 is a photograph taken by using a scanning electron microscope (SEM) after using the cleaning method of the present invention. [Description of main component symbols] 100 · Substrate 102 · Gate dielectric layer 102a, 108, 110, 301: Residue 104: Barrier layer 106: Gate layer 107, 109: Stacked structure 200, 202, 204, 206, 208: Step 11