! ' 436 9 6 6 五、發明說明（1) 本發明是有關於一種淺溝渠隔離製程’且特別是有關 於一種可減少殘留物之淺溝渠隔離製程。 習知的淺溝渠隔離製程，其步驟主要是利用微影程序 和蝕刻技術定義出硬罩幕圖案後，再以乾蝕刻法將未被硬 罩幕圖案覆蓋之基底蝕刻掉，形成一淺溝渠。接著，將絕 緣物填入淺溝渠後’便可完成淺溝渠隔離製程。 為使此習知淺溝渠隔離製程更清楚可見，玆將於第u 〜1C圖中詳細說明之。 首先’請參照第1A圖，提供一基底1 〇 0，例如表面已 形成有半導體元件之矽基底。其次，利用化學氣相沉積法 依序形成一墊氧化層11 〇以及一氮化物層i 2〇(例如氮化矽 層）於基底100上。然後，以微影程序形成一光阻圖案13〇 於氮化物層120上，並且在淺溝渠隔離通道（STI)預定處形 成一露出氮化物層120表面之窗口 140。 接著’請參照第1B圖，以光阻圖案1 3 0作為罩幕，利 用四氟化碳/三氟曱烷/氬氣（氣體比例如為15 :1〇 :1〇〇) 所構成之敍刻氣體，於壓力約5〇mT〇rr、能量約600瓦且磁 場強度為10G之條件下，乾姓刻去除窗口 ho下所裸露的氮 化物層120及墊氧化層11〇，定義出由墊氧化層11()和氮化 物層120所構成之硬罩幕層135。其中，硬罩幕層135並且 含有一露出基底100表面之姓刻窗口；140’ 。然而，由於姓 刻氣體中含有大量氟碳原子，因此在蝕刻時便會產生如圖 所示之含氟聚合物（CxFy) 1 50，並且殘留於光阻圖案130、 硬罩幕層135以及蝕刻窗口140，之基底1〇〇表面。'436 9 6 6 V. Description of the invention (1) The present invention relates to a shallow trench isolation process', and particularly to a shallow trench isolation process that can reduce residues. In the conventional shallow trench isolation process, the steps are mainly to define a hard mask pattern by using a lithography process and an etching technique, and then dry-etch the substrate not covered by the hard mask pattern to form a shallow trench. Then, after the insulation is filled in the shallow trench, the shallow trench isolation process can be completed. In order to make the conventional shallow trench isolation process more clearly visible, it will be described in detail in Figures u ~ 1C. First, please refer to FIG. 1A, and provide a substrate 100, such as a silicon substrate having a semiconductor element formed on the surface. Next, a chemical vapor deposition method is used to sequentially form a pad oxide layer 110 and a nitride layer i20 (such as a silicon nitride layer) on the substrate 100. Then, a photoresist pattern 13 is formed on the nitride layer 120 by a lithography process, and a window 140 is formed at a predetermined position of the shallow trench isolation via (STI) to expose the surface of the nitride layer 120. Next, please refer to FIG. 1B, using a photoresist pattern 130 as a cover, and using a tetrafluorocarbon / trifluoromethane / argon gas (for example, a gas ratio of 15: 10: 100). Under the conditions of a pressure of about 50mTorr, an energy of about 600 watts, and a magnetic field strength of 10G, the dry layer is etched to remove the exposed nitride layer 120 and the pad oxide layer 11 under the window ho. The hard mask layer 135 composed of the oxide layer 11 () and the nitride layer 120. Among them, the hard cover curtain layer 135 and a surname engraved window exposed on the surface of the substrate 100; 140 '. However, because the engraved gas contains a large number of fluorocarbon atoms, the fluoropolymer (CxFy) 1 50 shown in the figure is generated during etching, and remains in the photoresist pattern 130, the hard mask layer 135, and the etching. Window 140, the surface of the substrate 100.
1^11 IEMI 4369 6 6 五、發明說明（2) 星Ϊ參照訊圖，以光阻圖案13G和硬罩幕層咖 作為刻罩幕’利用溴化氫為主的電漿，乾蝕刻去除蝕刻 開口 H。’下裸露的基底100，並且形成一淺溝渠二除㈣ 然而，由於蝕刻開口14〇,表面殘留有如前所述之含 聚合物150，故在此乾蝕刻步驟中便會局部性地降低蝕刻 氣體對基底1〇〇之蝕刻速率，因此所形成的淺溝渠16〇便容 易產生如圖所示般的局部突起矽殘留物17〇。即使在光阻 圖案130去除過程中’經過光阻剥除電漿以及氫氟酸和後 續的B clean等處理，此突起的矽殘留物17〇之數目仍無法 有效地降低，因此往往會引起橋接反應（bridging)，或者 在後續的CMP步驟中造成元件表面被刮傷。 有鑑於此，本發明揭示一種可減少殘留物之淺溝渠隔 離製程，其特徵在於蝕刻定義出隔離用的淺溝渠後，於相 同環境（in-situ)再額外施一等向性蝕刻處理，如此便可 將突起的妙殘留物縮小或甚至將突起的矽殘留物清除。 本發明之一特徵是揭示一種可減少殘留物之淺溝渠隔 離製程’其步驟包括：提供一基底；形成一具特定圖案之 硬罩幕層於該基底上；蝕刻未被該硬罩幕層所覆蓋之該基 底’並且形成一淺溝渠；施一等向性蝕刻處理；以及 去除該硬罩幕層。 如上所述之製程’其中基底係矽基底，且此基底表面 更可包含有半導體元件。硬罩幕層之形成步驟則包括：依 序形成一墊氧化層以及一氮化物層於基底上；以及利用微 影程序和乾蝕刻技術’定義該氮化物層和該墊氧化層，形1 ^ 11 IEMI 4369 6 6 V. Description of the invention (2) Xingying refers to the picture, using the photoresist pattern 13G and the hard cover layer coffee as the engraving curtain. 'Using hydrogen bromide-based plasma, dry etching to remove etching Opening H. 'Under the exposed substrate 100, and a shallow trench is formed. However, since the etching opening 14o, the surface containing the polymer-containing 150 as described above, the etching gas will be locally reduced during this dry etching step. The etching rate to the substrate 100 is, so the shallow trench 16 formed is easy to produce a locally protruding silicon residue 17 as shown in the figure. Even in the process of removing the photoresist pattern 130, after the photoresist stripping plasma, hydrofluoric acid, and subsequent B clean, etc., the number of silicon residues 17 raised by this protrusion cannot be effectively reduced, so it often causes a bridging reaction. (Bridging), or the surface of the component is scratched in a subsequent CMP step. In view of this, the present invention discloses a shallow trench isolation process capable of reducing residues, which is characterized in that after the shallow trenches for isolation are defined by etching, an isotropic etching process is additionally performed in the same environment (in-situ). You can shrink the wonderful residue of the protrusion or even remove the protruding silicon residue. A feature of the present invention is to disclose a shallow trench isolation process capable of reducing residues. The steps include: providing a substrate; forming a hard mask layer with a specific pattern on the substrate; and etching the hard mask layer without the hard mask layer. Cover the substrate 'and form a shallow trench; apply an isotropic etching process; and remove the hard mask layer. In the above process, the substrate is a silicon substrate, and the surface of the substrate may further include a semiconductor element. The forming step of the hard mask layer includes: sequentially forming a pad oxide layer and a nitride layer on the substrate; and using a lithography process and a dry etching technique to define the nitride layer and the pad oxide layer, and the shape
擊修正-m\ ^369 6 6 88110625 行年 lnCorrection -m \ ^ 369 6 6 88 110 625 year ln
成-具特；t圖案之硬罩幕層。其+，氮化物層係由氮 構成’而硬罩幕層之乾姓刻步领所用之银刻氣體是由四： 化碳/三氟甲烷/1氣所構成。此外，等向性蝕刻處理所用 之蝕刻氣體是氯氣/氦氣，且等性蝕刻處理是於高壓且高 磁場強度之條件下進行，其墨力範圍為13〇〜175mT〇rr : 例如150mT〇rr·，且磁場強度範圍為7〇〜95G，如8〇(J。 本發明之另一特徵是揭示—種可減少殘留物之淺溝渠 严離製程，其步驟包括：提供一基底；依序形成一墊氧一 化 nm 層和一氮化物層於該基底上：利用微影程序和蝕刻技術定 ^晨義該氮化物層和該墊氧化層，形成一具特定圖案之硬罩幕 P示層；蝕刻未被該硬罩幕層所覆蓋之該基底，並且形成一淺 L年溝渠；施一等向性蝕刻處理；以及去除該硬罩幕層。Cheng-with special; t-patterned hard cover curtain layer. The +, nitride layer is composed of nitrogen, and the silver-engraved gas used for the dry-cut engraving collar of the hard cover layer is composed of four: carbonized carbon / trifluoromethane / 1 gas. In addition, the etching gas used in the isotropic etching process is chlorine gas / helium gas, and the isotropic etching process is performed under conditions of high pressure and high magnetic field strength, and its ink power range is 13 ~ 175mT0rr: for example, 150mT0rr · And the magnetic field intensity range is 70 ~ 95G, such as 80 (J. Another feature of the present invention is to disclose-a shallow trench strict separation process that can reduce residues, the steps include: providing a substrate; sequentially forming A pad of oxygen-based nm layer and a nitride layer on the substrate: the lithography process and etching technology are used to define the nitride layer and the pad oxide layer to form a hard mask P display layer with a specific pattern ; Etching the substrate not covered by the hard mask layer, and forming a shallow L-year trench; applying an isotropic etching treatment; and removing the hard mask layer.
Ham -7如上所述之製程’其中硬罩幕層之银刻步驟是利用乾 f月蝕刻法進行’而所用之蝕刻氣體是由四氟化碳/三氟曱烷/ ^戸氬氣所構成。此外’等向性蝕刻處理所用之蝕刻氣體是氣 氣/氦氣’等向性蝕刻處理是於高壓且高磁場強度之條件 °之下進行，其壓力範圍為130〜175mTorr，例如150mT〇rr ’ 且磁場強度範圍為70〜95G，例如80G。 本發明之另一特徵是揭示一種可減少殘留物之淺溝渠 隔離製程’其步驟包括：提供一基底；依序形成〆塾氧化 層和一氮化物層於該基底上；利用微影程序和蝕到技術定 義該氮化物層和該墊氧化層，形成一具特定圖案之硬罩幕 層；蝕刻未被該硬罩幕層所覆蓋之該基底，並且形成一淺 溝渠；施一等向性蝕刻處理；去除該硬罩暮層；以及在該The process of Ham -7 as described above, in which the silver engraving step of the hard cover layer is performed by dry etching method, and the etching gas used is composed of carbon tetrafluoride / trifluoromethane / argon argon . In addition, the etching gas used in the isotropic etching process is gas / helium gas. The isotropic etching process is performed under the condition of high pressure and high magnetic field strength °, and the pressure range is 130 ~ 175mTorr, for example, 150mT0rr. And the magnetic field strength range is 70 ~ 95G, for example 80G. Another feature of the present invention is to disclose a shallow trench isolation process capable of reducing residues. The steps include: providing a substrate; sequentially forming a hafnium oxide layer and a nitride layer on the substrate; using a lithography process and etching To the technical definition of the nitride layer and the pad oxide layer, a hard mask layer with a specific pattern is formed; the substrate not covered by the hard mask layer is etched, and a shallow trench is formed; an isotropic etching is applied Processing; removing the hard cover twilight layer; and
I麵 第6頁 436966 五、發明說明（4) 淺溝渠内填入—絕緣物質。 述之製程’其中硬罩幕層之蝕刻步驟是利用乾 复氣所構成。I:用=氣體是由四氟化破/三氣甲烧/ 氣/氦氣， 卜，等向性蝕刻處理所用之蝕刻氣體是氣 件下谁粁，甘等向性蝕刻處理是於高壓且高磁場強度之條 、壓力範圍為130〜i75mTorr，例如 mT〇rr，且磁場強度範圍為70〜90(ϊ ’例如80G。 發明ί Ϊ明之優點和特徵更清楚可見，玆將以根據本 發月之較佳實施例以及相關圖式，詳細說明如下。 圖式之簡單說明： 第1Α〜1C圖顯示的是習知一種淺溝渠隔離剖面製程。 第2Α〜2Ε圖顯示的是根據本發明之一種可減少殘留物 之淺溝渠隔離剖面製程。 符號說明： 100〜基底；110〜墊氧化層；120〜氮化物層；1 30光 阻圖案；135〜硬罩幕層；140〜窗口； 140，〜蝕刻窗口； 〜含氟聚合物；160〜淺溝渠；170〜石夕殘留物；2〇〇〜 基底；210〜墊氧化層；220〜氮化物層；230〜光阻圖 案；235〜硬罩幕層；240〜窗口 ；240，〜蝕刻窗口； 250 〜含氟聚合物；260、280〜淺溝渠；270〜矽殘餘物；290 〜氧化矽；300〜淺溝渠隔離通道。 實施例： 首先，請參照第2Α圖，提供一基底200，例如表面已 形成有半導體元件之矽基底》其次，利用化學氣相沉積法Side I Page 6 436966 V. Description of the invention (4) Filling in shallow trenches-insulation material. The described process' wherein the etching step of the hard mask layer is formed by using dry gas. I: The gas used is the tetrafluoride / three gas burner / gas / helium gas, and the isotropic etching process is used for the isotropic etching. The isotropic etching process is performed under high pressure and The high magnetic field strength, pressure range is 130 ~ i75mTorr, such as mT〇rr, and the magnetic field strength range is 70 ~ 90 (ϊ 'for example, 80G. The advantages and characteristics of the invention Ϊ 更 明 are more clearly visible, will be based on this month The preferred embodiment and related drawings are described in detail below. Brief description of the drawings: Figures 1A to 1C show a conventional shallow trench isolation profile process. Figures 2A to 2E show a method according to the present invention. Shallow trench isolation profile process that can reduce residues. Symbol description: 100 ~ substrate; 110 ~ pad oxide layer; 120 ~ nitride layer; 1 30 photoresist pattern; 135 ~ hard cover curtain layer; 140 ~ window; 140, ~ Etching window; ~ fluoropolymer; 160 ~ shallow trench; 170 ~ Shi Xi residue; 2000 ~ substrate; 210 ~ pad oxide layer; 220 ~ nitride layer; 230 ~ photoresist pattern; 235 ~ hard mask Layer; 240 ~ window; 240, ~ etched window; 250 ~ Fluoropolymer; 260, 280 ~ shallow trench; 270 ~ silicon residue; 290 ~ silicon oxide; 300 ~ shallow trench isolation channel. Example: First, please refer to FIG. 2A to provide a substrate 200, for example, a surface has been formed Silicon substrates for semiconductor devices "followed by chemical vapor deposition
4369 6 6 五、發明說明（5) 依序形成一墊氧化層210以及一氣化物層220(例如氮化梦 層）於基底200上。然後，以微影程序形成一光阻圖案230 於氮化物層220上，並且在淺溝渠隔離通道預定處形成一 露出氮化物層220表面之窗口 240。 其次，請參照第2B圖，以光阻圖案230作為罩幕，利 用四氟化碳/三氟甲烷/氬氣（氣體比例如為15 : 10 : 1〇〇) 所構成之触刻氣體，於壓力約50mTorr、能量約600瓦且磁 場強度為10G之條件下，乾蝕刻去除窗口 240下所裸露的氮 化物層220和位於其下之墊氧化層210，定義出由墊氧化層 210和氮化物層220所構成之硬罩幕層23 5。其中，硬罩幕 層235並且含有一露出基底2〇〇表面之蝕刻窗口240，。然 而，由於蝕刻氣體中含有大量氟碳原子，因此在蝕刻過程 便會產生如圖所示之含氟聚合物250，並且殘留於光阻圖 案23 0、硬罩幕層235以及蝕刻窗口 240’之基底200表面。 接著請參照第2C圖，以光阻圖案230和硬罩幕層235 作為蝕刻罩幕’利用溴化氫為主的電漿，乾蝕刻去除蝕刻 開口 240’下裸露的基底200，並且形成一隔離用的淺溝渠 260 ^不過’由於蝕刻開口24〇’表面殘留有如前所述之含 I聚合物250 ’故在此乾蝕刻步驟中便會局部性地降低蝕 刻氣體對基底200之蝕刻速率，因此所形成的淺溝渠26〇便 會產生如圖所示般的局部突起矽殘留物2 70。 接著’請參照第2D圖。為避免突起的矽殘留物270引 起主動區產生橋接反應（bridging)，或者在後續的CMP步 驟中造成元件表面被刮傷。因此，本實施例乃於淺溝渠 4369 b b 88110625 五、發明說明（6) 260形成後’於相同環境（in-si tu)再施—等向性截刻處 理’將突起的石夕殘留物270縮小或甚至將突起的石夕殘留物 270清除。此等向性蝕刻處理步驟是利用氯氣/氦氣（氣體 比例如為50 : 1 00)所構成之電漿氣體，於能量約瓦之 高氣體壓力（150 mTorr)以及高磁場（80G)條株為 時約_。因&，藉由高氣體壓力以及高磁条=二為 件，以提高電漿氣體對殘留物270之等向蝕刻性便可將 殘留物270縮小或甚至將殘留物清除，以獲得一隔離用的 理想淺溝渠280。 最後，請參照第2E圖，利用氣相沈積以及回蝕刻等步 驊將氧化碎290填入淺溝渠280内後’便可完成一淺溝渠隔 離通道300，惟此步驟並非本發明之特徵，故在此不'再贅 述。 雖然本發明已以較佳實施例揭露如上，然其並非用以 限3本發日月，任何熟習此技藝者，在不脫離本發明之精神 和祝圍内，所作之各種更動與潤飾均落在本發明之扩， :界str之專利保護範圍當視後附之申請專“圍4369 6 6 V. Description of the invention (5) A pad oxide layer 210 and a vaporized layer 220 (such as a nitride nitride layer) are sequentially formed on the substrate 200. Then, a photoresist pattern 230 is formed on the nitride layer 220 by a lithography process, and a window 240 is formed at a predetermined position of the shallow trench isolation channel to expose the surface of the nitride layer 220. Next, referring to FIG. 2B, the photoresist pattern 230 is used as a cover, and an etching gas composed of carbon tetrafluoride / trifluoromethane / argon gas (for example, a gas ratio of 15: 10: 100) is used. Under the conditions of a pressure of about 50 mTorr, an energy of about 600 watts, and a magnetic field strength of 10 G, dry etching removes the exposed nitride layer 220 and the pad oxide layer 210 under the window 240, and defines the pad oxide layer 210 and the nitride The hard cover curtain layer 235 formed by the layer 220. The hard mask layer 235 includes an etching window 240 that exposes the surface of the substrate 2000. However, because the etching gas contains a large number of fluorocarbon atoms, the fluoropolymer 250 as shown in the figure is generated during the etching process and remains in the photoresist pattern 230, the hard mask layer 235, and the etching window 240 '. The surface of the substrate 200. Next, referring to FIG. 2C, the photoresist pattern 230 and the hard mask layer 235 are used as an etching mask. 'Using hydrogen bromide-based plasma, dry etching removes the bare substrate 200 under the etching opening 240', and forms an isolation. The used shallow trench 260 ^ However, since the I-containing polymer 250 as described above remains on the surface of the etching opening 24 ′, the etching rate of the substrate 200 by the etching gas is locally reduced during this dry etching step, so The shallow trench 26 formed will produce locally protruding silicon residue 2 70 as shown in the figure. Next, 'please refer to FIG. 2D. In order to prevent the raised silicon residue 270 from causing bridging in the active area, or in the subsequent CMP step, the component surface is scratched. Therefore, this example is a shallow trench 4369 bb 88110625 V. Description of the invention (6) 260 'formed in the same environment (in-si tu)-isotropic truncation treatment' will remove the protruding stone eve residue 270 Shrink or even remove the protruding stone residue 270. This isotropic etching process uses a plasma gas composed of chlorine gas / helium gas (for example, a gas ratio of 50: 100) at a high gas pressure (150 mTorr) and a high magnetic field (80G) of about watts It was about _. Because of & by using high gas pressure and high magnetic strip = two as the pieces, to improve the isotropic etching property of the plasma gas to the residue 270, the residue 270 can be reduced or even removed to obtain an isolation. Used ideal shallow trench 280. Finally, please refer to FIG. 2E. After filling the oxide trenches 290 into the shallow trenches 280 using steps such as vapor deposition and etch back, a shallow trench isolation channel 300 can be completed. I won't repeat them here. Although the present invention has been disclosed in the preferred embodiment as above, it is not intended to limit the date and time. Any person skilled in this art can make all kinds of changes and decorations without departing from the spirit and wishes of the present invention. In the expansion of the present invention, the scope of patent protection of the circle str