五、發明説明（） 發明領域： 本發月係有關於一種姓刻劑及其在提高蝕刻選擇比 (Etchmg Selectivity)上之應用，特別是有關於一種具有含 矽（Si)化合物之蝕刻劑及其在提高氮化矽（ShN4)盘氧化 矽（Si02)之蝕刻選擇比上的應用。 發明背景： 在積體電路中，為了避免電晶體之間的操作互相干 擾，因而必須在相鄰的電晶體間加入具電性隔絕能力的隔 離結構，以防止電晶體間發生閉鎖（Latch Up)或是短路。然 而，伴隨半導體元件尺寸的微小化趨勢，致使元件之積集 度持續攀升；^疋元件間隔離結構之尺寸也愈顯關鍵。 目則’由於淺溝渠隔離（Shallow Trench Isolation ; STI) 技術所形成之隔離結構不僅尺寸小、平坦度佳，具有良好 的電性隔離效果，更能大幅提高元件密度。因此在現今的 積體電路製程中，淺溝渠隔離技術已廣為採用。 請參照第1圖至第4圖，其係繪示習知淺溝渠隔離之 製程剖面®。製作元件間之淺溝渠隔離時，首先在半導體 之基材1〇〇上覆蓋氧化矽層102來作為墊氧化層（pad〇xide Layer)，再於氧化矽層1〇2上覆蓋氮化矽層ι〇4。其中，氧 化夕層1 02係用以降低存在於氮化石夕層i 〇4與基材1⑽間 | |之應力，而氮化石夕層104則係用以在後續之製程中作為淺 1 溝渠隔離之化學機械研磨（Chemical Meehanical I poIishing;CMP)的終止層。接著，覆蓋一層光阻層106於 本紙張尺度適用中國國家標準(CNS)A4規格(210X297公釐) 574351 A 7 __ B7 五、發明説明（） (請先閲讀背面之注意事項再填寫本頁) 虱化矽層1 04上，並利用微影製程圖案化此光阻層i 〇6， 而暴露出部分之氮化矽層104。再利用圖案化之光阻層1〇6 為蝕刻罩幕，對所暴露出之氮化矽層1〇4及其底下之氧化 矽層1 02與基材1 00進行蝕刻，藉以去除部分之氮化矽層 104、部分之氧化矽層102、以及部分之基材1〇〇，而在氮 化矽層104、氧化矽層102、以及基材1〇〇中形成淺溝渠隔 離之開口 1 08，所形成之結構如第1圖所示。 開口 形成後，將其餘之光阻層1〇6去除而暴露出 氮化矽層104。再形成一層氧化矽層丨1〇覆蓋在開口 1〇8 所暴露出之基材100、氧化矽層102、氮化矽層1〇4上，並 填滿開口 1 08，而形成如第2圖所示之結構。 然後，請參照第3圖，利用化學機械研磨的方式，且 以氮化矽層104為研磨終點，去除氮化矽層1〇4上之氧化 石夕層110，而留下位於開口 1〇8中之氧化矽層11〇以形成 淺溝渠隔離結構1 12。研磨步驟完成後，以熱磷酸 (Phosphoric Acid ; H3P〇4)當蝕刻劑去除氮化矽層1〇4，而 暴露出氧化矽層1 〇2。然而，以熱磷酸蝕刻氮化矽層1 〇4 的同時，熱磷酸亦會攻擊氧化矽層1 02，而氧化石夕層i 〇2 之厚度也因而產生改變’導致氧化矽層1 〇 2之厚度不均。 經濟部智慧財產局員工消費合作社印製 為了確保後續之離子植入的可靠度，必須將此厚度不 均之氧化矽層102去除，而暴露出基材1〇〇。再形成一層 氧化矽層114覆蓋在所暴露之基材1〇〇上，來作為離子植 入步驟之犧牲氧化層。然而，在去除氧化矽層丨〇2時，大 3 本紙張尺度適用中國國家標準(CNS)A4規格(210X297公釐) A7V. Description of the Invention () Field of the Invention: The present invention relates to a family name etchant and its application in improving the etch selectivity (Etchmg Selectivity), in particular to an etchant having a silicon (Si) -containing compound and Its application is to improve the etching selection ratio of silicon nitride (ShN4) disk silicon oxide (Si02). Background of the Invention: In integrated circuits, in order to avoid interference between the operations of transistors, it is necessary to add an isolation structure with electrical isolation between adjacent transistors to prevent latch-up between the transistors. Or short circuit. However, with the trend of miniaturization of the size of semiconductor devices, the accumulation of devices has continued to rise; the size of the isolation structure between devices has become more critical. The goal is that the isolation structure formed by the Shallow Trench Isolation (STI) technology not only has a small size and good flatness, but also has a good electrical isolation effect, which can greatly increase the component density. Therefore, in today's integrated circuit manufacturing processes, shallow trench isolation technology has been widely adopted. Please refer to Figures 1 to 4 for the process profile ® of the conventional shallow trench isolation. When making shallow trench isolation between components, first a silicon oxide layer 102 is covered on the semiconductor substrate 100 as a pad oxide layer, and then a silicon nitride layer is covered on the silicon oxide layer 102. ι〇4. Among them, the oxide layer 102 is used to reduce the stress existing between the nitride layer i 0 4 and the substrate 1 |, and the nitride layer 104 is used as a shallow trench isolation in subsequent processes. The stop layer of Chemical Meehanical I PoIishing (CMP). Next, cover a layer of photoresist layer 106 to the Chinese paper standard (CNS) A4 specification (210X297 mm) 574351 A 7 __ B7 at this paper scale V. Description of the invention () (Please read the precautions on the back before filling this page) The silicon layer 104 is etched, and the photoresist layer io6 is patterned by a lithography process, and a part of the silicon nitride layer 104 is exposed. The patterned photoresist layer 10 is used as an etching mask to etch the exposed silicon nitride layer 104 and the underlying silicon oxide layer 102 and the substrate 100 to remove part of the nitrogen. The siliconized layer 104, a portion of the silicon oxide layer 102, and a portion of the substrate 100 are formed, and a shallow trench isolation opening 108 is formed in the silicon nitride layer 104, the silicon oxide layer 102, and the substrate 100. The resulting structure is shown in Figure 1. After the opening is formed, the remaining photoresist layer 106 is removed to expose the silicon nitride layer 104. A further layer of silicon oxide is formed on the substrate 100, silicon oxide layer 102, and silicon nitride layer 104 exposed by the opening 108, and the opening 108 is filled to form a layer as shown in FIG. 2 The structure shown. Then, referring to FIG. 3, using the chemical mechanical polishing method, and using the silicon nitride layer 104 as the polishing end point, the stone oxide layer 110 on the silicon nitride layer 104 is removed, and the opening 108 is left. The silicon oxide layer 11 is formed in the silicon oxide layer 11 to form a shallow trench isolation structure 1 12. After the polishing step is completed, the silicon nitride layer 104 is removed by using a hot phosphoric acid (Phosphoric Acid; H3P04) as an etchant, and the silicon oxide layer 102 is exposed. However, while the silicon nitride layer 1 0 4 is being etched with hot phosphoric acid, the hot phosphoric acid will also attack the silicon oxide layer 102, and the thickness of the stone oxide layer i 0 2 will be changed accordingly. Uneven thickness. Printed by the Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs In order to ensure the reliability of subsequent ion implantation, the silicon oxide layer 102 with uneven thickness must be removed to expose the substrate 100. A silicon oxide layer 114 is formed on the exposed substrate 100 to serve as a sacrificial oxide layer in the ion implantation step. However, when removing the silicon oxide layer, the paper size of the paper is applicable to the Chinese National Standard (CNS) A4 (210X297 mm) A7.
574351 五、發明説明（） 都係採用氟化氫（HF)來當作蝕刻 ^ ^ 卞蝕刻劑，而氟化氫不僅僅攻擊 氧化矽層1 〇2，也會攻擊構忐％、蓉下 又單構成淺溝渠隔離結構112之 矽材料。因此，在氧化矽層102 、 玄降俊 軋化氫會損壞漭 溝渠隔離結構1 1 2，而在潘、、盖堡 庚溝渠隔離結構112上形成凹凸 不平的表面，如第4圖所示。 發明目的及概述： 雲於上述習知淺溝渠隔離妒tb - 離t %中，受限於蝕刻劑對氮 化石夕層與氧化石夕層間之钱刻 〗選擇比，致使墊氧化層受損而 必須先予以去除，再另外形成屋许 成厚度較為均句之犧牲氧化層 以利離子植入步驟的進行。如+ . 、 刃琨仃如此一來，將導致製程更為繁 複，加重成本負擔。此外，a本^β 在去除塾乳化層的同時，姓刻 劑氟化氫亦會傷害到氧化石夕έ日士、> j虱化矽組成之淺溝渠隔離結構，嚴重 影響製程可靠度與良率。 因此，本發明的主要目的 — 的之 為k供一種姓刻劑，其 係在填酸中4參入含石夕化合物 士 /化口物。由於，含矽化合物會與水產 生水解反應’而有利於鱗酸血U昝 、Μ ϋ夂/、虱化矽之反應的進行。因此，574351 V. Description of the invention () Both use hydrogen fluoride (HF) as an etching agent, and hydrogen fluoride not only attacks the silicon oxide layer 102, but also attacks the structure%, and also forms a shallow trench. Silicon material of the isolation structure 112. Therefore, rolling silicon on the silicon oxide layer 102 and Xuan Jiangjun will damage the trench isolation structure 112, and an uneven surface is formed on the Pan, Gaibao Geng trench isolation structure 112, as shown in FIG. The purpose and summary of the invention: In the conventional shallow trench isolation jealousy tb-away t%, it is limited by the etching ratio of the etchant to the nitrided oxide layer and the oxided stone layer, which results in damage to the pad oxide layer. It must be removed first, and then a sacrificial oxide layer with a relatively uniform thickness can be formed to facilitate the ion implantation step. Such as +., Blades will cause more complicated processes and increase the cost burden. In addition, at the same time as the β emulsified layer is removed, the nickname hydrogen fluoride will also damage the shallow trench isolation structure composed of oxidized stone and silicon, which seriously affects the reliability and yield of the process. . Therefore, the main purpose of the present invention is to provide a surname engraving agent, which is used in the filling of acid to enter the stone-containing compound. Since the silicon-containing compound will hydrolyze with water, it is beneficial to the reaction of scaly blood U 昝, Mϋ 夂 /, and lice to silicon. therefore,
可大幅提升蝕刻劑氮化石夕盥g # r/7 > 0S 见化呀興虱化矽之間的蝕刻選擇比。 本發明之另一目的就是因為摻有含矽化合物盥磷酸之 姓刻劑可增加氮化石夕與氧化石夕間之敍刻選擇比，因此在去 除氮化層的同時’可有效維持墊氧化層之厚度。 本發明之再—目的就是因為在蝕刻氮化層期間，其下 方之塾氧化層的厚度可择得維姓 m ,, Jt· ^ X J獲付維持，因此墊氧化層可在後續 製程中作為犧牲氧化厝夕闲。A i _ Μ 九化層之用。如此，不僅可避免在墊氧化 本紙張尺度適用中國國家標準(CNS)A4規格(210X297公釐) .............•裝........·訂.........S (請先閲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 574351 A7It can greatly improve the etching selection ratio between silicon nitride etchant g # r / 7 > 0S. Another object of the present invention is that the addition of a silicon-containing compound containing phosphoric acid can increase the selectivity ratio between nitrided stone and oxidized stone, so it can effectively maintain the pad oxide layer while removing the nitrided layer. Of thickness. Another purpose of the present invention is that during the etching of the nitrided layer, the thickness of the samarium oxide layer below it can be selected and maintained, so that the pad oxide layer can be sacrificed in subsequent processes. Oxidation Xixi leisure. The use of A i _ 九 nine layers. In this way, not only can the pad oxidation be prevented from applying the Chinese National Standard (CNS) A4 specification (210X297 mm) to the paper size ............. • Installation ........ · Order ......... S (Please read the notes on the back before filling out this page) Printed by the Employee Consumption Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs 574351 A7
、發明説明( 經濟部智慧財產局員工消費合作社印製 層去除時蝕刻劑對淺溝渠隔離結 & :額外製作犧牲氧化層所產生之人力 =用的傷=，更可省 製程可靠度與良率，減少製程成本的支出。ι可改善 根據以上所述之目的，本發 適用於㈣氣切，至少包括：一碟：;、二種㈣劑， 物摻入上述之璘酸中…此含梦化合物且切化合 約9。_至約l80ppm之間。此切化合物：：：度介於 合物，例如含鹵素矽化合物或者是 7 ’合性矽化 生物等。 #疋3 _切化合物及其衍 之二ΓΓ述…’本發明另外更提供了-種上述 =刻其係用以提高氮化㈣氧化…刻選 擇比’其中利用上述之姓刻劑來提高餘刻選擇比之方法至 二包括：提供-基材，…基材上至少包括依序堆叠之 乳化石夕層以及-氮切層；以及利用上述之㈣劑對上 ^之氮切層進行㈣，藉以去除上述之氮切層，並暴 露出氮化矽層底下之氧化矽層’其中此蝕刻劑至少包括i 磷酸以及一含矽化合物摻入磷酸中。上述之含矽化合物為 可溶性，且此含矽化合物例如為含齒素矽化合物或含_素 石夕化合物及其衍生物等’較佳之例子為氣化石夕或氣化石夕及 其衍生物。 圖式簡單說明： 本發明的較佳實施例將於往後之說明文字中辅以下列 圖形做更詳細的闡述，其中： 本紙張尺度適用中國國家標準(CNS)A4規格(210X297公釐) .............·¥.........、耵.........S (請先閲讀背面之注意事項再填寫本頁) 574351 基材 102 氧化發層 氮化矽層 106 光阻層 開口 110 氧化矽層 淺溝渠隔離結構 114 氧化碎^層 基材 202 氧化秒層 氮化砍層 206 光阻層 開口 210 氧化矽層 212 淺溝渠隔離結構 發明詳細說明： A7 B7 五、發明説明（） 第1圖至第4圖係繪示習知淺溝渠隔離之製程剖面 圖；以及 第5圖至第8圖係繪示本發明之一較佳實施例之淺溝 渠隔離的製程剖面圖。 圖號對照說明： 100 104 108 112 200 204 208 本發明揭露一種蝕刻劑及其在提高蝕刻選擇比上之 應^，此#刻劑至少包括填酸以及含石夕化合物。藉由含石夕 化，物能與水產生水解反應的特性，可使蝕刻劑對氮化矽 與虱化矽之蝕刻選擇比獲得有效提升，進而 化層之厚度的目的。為了使本發明之敘述更加 備，可參照下列描述並配合第5圖至第8圖之圖示。 請參照第5圖至第8圖，其係繪示本發丁 4 -車交佳貫 施例之、淺溝渠隔離的製程剖s圖。本發明之“渠隔離結 構的製作，首先係在半導體之基材2〇〇上以例如沉積的方 本紙張尺度適用中國國家標準(CNS)A4規格(210X 297公釐) .............«^.........、耵.........^9 (請先閲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 574351 經濟部智慧財產局員工消費合作社印製 A7 五、發明説明（ 式覆蓋氧化矽層202，再以例如^ Λ 9η. ^ ^如》儿積的方式形成氮化矽層 2〇4覆盍在氧化石夕層202上，： , 上其中基材200之材料可例如 為石夕。上述之氧化矽層202又辎炎也γ 又稱為墊氧化層，可作為氮化 石夕層204與基材200之間的 J馬刀綾衝，而氮化矽層2〇4貝ij 可於淺溝渠隔離材料之化學遞、# π Tt <化予铖械研磨步驟中，當作研磨終 止層。接著，形成光阻層206覆蓋在氮化石夕層2〇4上，並 利用例如微影的技術於光阻層2〇6中定義出淺溝渠之圖 案，而暴露出部分之氮化石夕層2〇4。完成光阻層2〇6之圖 案化後’藉由例如姓刻的方式，並以光阻層2〇6為触刻罩 幕，去除光阻層206所暴露之氮化石夕層2〇4及其底下之氧 化石夕層202與部分之基材2〇〇，而在部分之氮化石夕層2〇4、 部分之氧化石夕層202、以及部分之基材·中形成淺溝渠 隔離之開口 208，如第5圖所示。 淺溝渠隔離之開口 208形成後，剝除剩餘之光阻層 2〇6,並暴露出氮化矽層204。此日寺，以例如高密度電聚化 學氣相沉積（High Density Plasma chemical Vapor、 Explanation of the invention (When the printed layer of the consumer cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs removes the printed layer from the etchant, it is used to isolate the shallow trench from the etchant. &Amp; Rate, reducing the cost of process costs. Ι can improve according to the purpose described above, this hair is suitable for radon gas cutting, including at least: a dish:;, two tinctures, the material is incorporated into the above-mentioned osmic acid ... this contains Dream compound and cleavage contract 9. _ to about l80ppm. This cleavage compound ::: Degree is between compounds, such as halogen-containing silicon compounds or 7 'synthetic silicified organisms, etc. # 疋 3 _chete compounds and their The description of the second ΓΓ ... 'The present invention also provides-a kind of the above = is used to improve the oxidation of osmium nitride ... etch selection ratio' wherein the method of using the above-mentioned last name etchants to improve the remaining selection ratio to two includes : Providing-a substrate, ... the substrate includes at least an emulsified stone layer and a nitrogen-cutting layer that are sequentially stacked; and using the above-mentioned tincture to purge the upper nitrogen-cutting layer to remove the nitrogen-cutting layer, And exposed under the silicon nitride layer Siliconized layer 'wherein the etchant includes at least i-phosphoric acid and a silicon-containing compound incorporated into the phosphoric acid. The above silicon-containing compound is soluble, and the silicon-containing compound is, for example, a dentate-containing silicon compound or a sulfide-containing compound and The preferred examples of its derivatives etc. are gaseous rock or gaseous rock and its derivatives. Brief description of the drawings: The preferred embodiments of the present invention will be explained in more detail in the following explanatory text with the following figures , Of which: This paper size applies to China National Standard (CNS) A4 specification (210X297 mm) ............. ¥ ........., 耵 .... ..... S (Please read the precautions on the back before filling out this page) 574351 Substrate 102 Oxidation layer Silicon nitride layer 106 Photoresist layer opening 110 Silicon oxide layer Shallow trench isolation structure 114 Oxidation broken layer substrate 202 Second oxide layer Nitridation layer 206 Photoresist layer opening 210 Silicon oxide layer 212 Shallow trench isolation structure invention detailed description: A7 B7 V. Description of the invention () Figures 1 to 4 show the conventional shallow trench isolation Sectional views of the manufacturing process; and Figures 5 to 8 show a preferred embodiment of the present invention An example is a cross-sectional view of a shallow trench isolation process. Comparative illustration of drawing numbers: 100 104 108 112 200 204 208 The present invention discloses an etchant and its application in improving the etching selectivity ratio. This #etchant includes at least filling acid and containing Shi Xi compounds. By containing Shi Xi chemical, the property can produce hydrolysis reaction with water, so that the etching selectivity of the etchant for silicon nitride and lice silicon can be effectively improved, and the purpose of the thickness of the layer. To make the description of the present invention more complete, you can refer to the following description and cooperate with the diagrams in Figs. 5 to 8. Please refer to Figs. 5 to 8 which show the example of the present invention 4-Chejiao Jiaguan The process cross-section diagram of shallow trench isolation. The production of the "canal isolation structure" of the present invention is firstly applied on the semiconductor substrate 200 in accordance with the Chinese paper standard (CNS) A4 specification (210X 297 mm) on the basis of the deposited paper size ... ....... «^ ........., 耵 ......... ^ 9 (Please read the notes on the back before filling out this page) Employees of the Bureau of Intellectual Property, Ministry of Economic Affairs Printed by the Consumer Cooperative 574351 Printed by the Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs A7 Printed by the Consumer Cooperative 5. Cover the silicon oxide layer 202, and then form a silicon nitride layer 2 such as ^ Λ 9η. 4 Overlay on the oxidized stone layer 202: The material of the base material 200 may be, for example, the stone. The above-mentioned silicon oxide layer 202 is also known as a pad oxide layer, and can be used as a nitrided stone layer. The J saber punch between 204 and the substrate 200, and the silicon nitride layer 204 may be used in the chemical transfer of the shallow trench isolation material, # π Tt < to the mechanical grinding step, as grinding termination Then, a photoresist layer 206 is formed to cover the nitrided layer 204, and a pattern such as a photolithography is used to define a shallow trench pattern in the photoresist layer 206. A part of the nitride nitride layer 204 is exposed. After the patterning of the photoresist layer 206 is completed, the photoresist layer is removed by using, for example, the method of last name engraving and using the photoresist layer 206 as a engraving mask. The exposed nitrided oxide layer 204 and the underlying oxided stone layer 202 and part of the substrate 200 are exposed in 206, and the partially nitrided stone layer 204 and the partially oxided layer 202, and Part of the base material · a shallow trench isolation opening 208 is formed, as shown in Figure 5. After the shallow trench isolation opening 208 is formed, the remaining photoresist layer 206 is stripped, and the silicon nitride layer 204 is exposed. Today, temples, such as High Density Plasma chemical Vapor
Deposition; HDP CVD)的方式形成氧化矽層21〇覆蓋在開 口 208所暴露出之基材200與氧化矽層202、以及氮化砂 層204上，並使此氧化矽層210填滿開口 208，而形成如 第6圖所示之結構。 在氧化矽層2 1 0填滿開口 208後，利用例如化學機械 研磨的方式’並以氣化石夕層2 0 4為研磨終點，去除部分之 氧化石夕層2 1 0，將開口 2 0 8以外之氧化石夕層2 1 〇移除，而 — — — — — — — — — — — — — — — — — — — — — — — — — — — — I I (請先閲讀背面之注意事項再填寫本頁) 本紙張尺度適用中國國家標準(CNS)A4規格(210X297公釐) 574351Deposition; HDP CVD). A silicon oxide layer 21 is formed on the substrate 200, the silicon oxide layer 202, and the nitrided sand layer 204 exposed by the opening 208, and the silicon oxide layer 210 fills the opening 208. The structure shown in FIG. 6 is formed. After the silicon oxide layer 2 1 0 fills the opening 208, a method such as chemical mechanical polishing is used and the gasified stone layer 2 0 4 is used as the polishing end point, and a part of the stone oxide layer 2 1 0 is removed to open the opening 2 8 Outside the oxide stone layer 2 1 〇 and remove — — — — — — — — — — — — — — — — — — — — — — — — — — — (Please read the precautions on the back first (Fill in this page again) The paper size is applicable to China National Standard (CNS) A4 (210X297 mm) 574351
、發明說明( 經濟部智慧財產局員工消費合作社印製 208中形成淺溝渠隔離結構川，所形成之結構如 第7圖所示。 請參照第8圖，漭；盖退R5她Α丄 曼溝渠隔離結構212形成後，利用棘 刻劑對氮化矽層204推私^ *丨— ?ΠΛ 仃钱刻’藉以去除剩餘之氮化矽層 ζυ4 ’而暴露出氧化矽層2〇2 〇 t ^ ^ ^ 曰〇2其中，本發明之蝕刻劑至少 已括磷酸以及含矽化合物， 勿且此3矽化合物屬水溶性。此 ^此切化合物之濃度較佳是介於約9Gppmu180ppn :;。然，含带化合物可依製程需求而改變其添加量’其 2並不限於以上所述。而上述之切化合物可例如為含 =切化合物或“切化合物及㈣生物，例如氣化石夕 或氣化矽及其衍生物等。 由於切化合物可與水產生水解反應，因此有利於蛾 酉夂與乱切反應，可大幅提高姓刻劑對氮切與氧化石夕之 姓刻選擇比。在本發明之—較佳實施例中，填酸與含石夕化 合物所構成之蝕刻劑可蔣翁 將鼠化石夕對氧化矽之蝕刻選擇比從 大約30提升至約50’甚至可達6〇以上。此外，含石夕化合 :丄水解反應後’戶斤生成之副產物並不會對晶圓產生衝 擎。舉例而言，若所潠用人 ^ __ 、用之3矽化合物為氣化矽，則所生 、之副產物為氯化氫，而氣化氫也屬水溶性，i不會對晶 圓產生不好的影響。 由於本發明之餘刻劑對氮化石夕與氧化石夕具有絕佳之姓 刻選擇比’因此制此㈣劑去除氮切@ 2Q4時，可大 幅降低㈣劑對氧切層加之㈣，而使得氧化梦層2〇2 .........·¥.........1T.........參 (請先閱讀背面之注意事項再填寫本頁)Description of the invention (The shallow trench isolation structure is formed in the printed 208 of the Consumer Cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs, and the structure formed is shown in Figure 7. Please refer to Figure 8, 漭; cover R5 and Α 丄 mann ditch After the isolation structure 212 is formed, the silicon nitride layer 204 is promoted with a spinner ^ * 丨-? ΠΛ Save money to etch 'the remaining silicon nitride layer ζυ4' to expose the silicon oxide layer 002 t ^ ^ ^ Said 02, wherein the etchant of the present invention has at least phosphoric acid and silicon-containing compounds, not to mention that the 3 silicon compounds are water-soluble. The concentration of this cut compound is preferably between about 9Gppmu180ppn :; of course, The content of the band-containing compound can be changed according to the requirements of the process. The number 2 is not limited to the above. The above-mentioned cutting compound may be, for example, a cutting compound or a "cutting compound and a tritium, such as gasified stone or siliconized gas. And its derivatives, etc. Because the cutting compound can hydrolyze with water, it is favorable for the moth and random cutting reaction, which can greatly increase the selection ratio of the last name engraving agent to the last name cut of nitrogen cutting and oxidized stone. In the present invention, —In the preferred embodiment, fill The etchant composed of the compound containing Shixi can increase the etching selection ratio of rat fossil to silicon oxide from about 30 to about 50 'or even more than 60. In addition, the compound containing Shixi: after the hydrolysis reaction 'The by-products produced by households do not have an impact on wafers. For example, if the silicon compound used is ^ __ and the silicon compound used is gasified silicon, the by-product produced is hydrogen chloride, and gas Hydrogen hydride is also water-soluble, and i will not have a bad effect on the wafer. Since the etchant of the present invention has an excellent selection ratio of nitrite and oxidized stone, so this elixir is used to remove nitrogen. When cutting @ 2Q4, it can greatly reduce the effect of tincture on the oxygen cut layer and the oxidized layer, so that the oxide dream layer 2 02 ......... ¥ ......... 1T .... ..... Refer to (Please read the notes on the back before filling this page)
574351 五、發明説明（ 之厚度可獲得有效維持。除此 从傲、&、*.、- 卜亦可同時避免氧化矽 、之淺溝渠隔離結構2 i 2遭到蝕刻劑的傷宝。 (請先閲讀背面之注意事項再填寫本頁) 此外，由於氧化石夕層202之厚度獲得維;，因此氧化 矽層202之厚度均勾度可獲得有效改善。如此一來，氧化 :層202可直接當作犧牲氧化層，而不需先將氧化梦層加 去除後再另外形成犧牲氧化層。不僅可減輕製程負擔，更 可提高製程之可靠度。 本發明之-優點就是因為本發明之姓刻劑中接有水溶 欧之含每7化合物’因此可逵到夫但古a,, 口此』運引大巾田楗南蝕刻劑對氮化矽盥 氧化矽之蝕刻選擇比之目的。 ^ 本發明之另一優點就是因為應用本發明之蝕刻劑可有 效提升氮化矽與氧化矽間之蝕刻選擇比，因此可於氮化矽 層去除後，獲得厚度均勻度佳之墊氧化層。 本發明之又一優點就是因為墊氧化層之厚度獲得維 持，可不需再另行製作犧牲氧化層，因此可簡化製程步驟， 降低製程成本。 本發明之再一優點就是因為不需額外製造犧牲氧化 層，因此可提高淺溝渠隔離結構之品質，達到提升製程可 靠度與良率的目的。 經濟部智慧財產局員工消費合作社印製 如熟悉此技術之人員所瞭解的，以上所述僅為本發明 之較佳實施例而已，並非用以限定本發明之申請專利範 圍；凡其它未脫離本發明所揭示，之精神下所完成之等效改 變或修飾，均應包含在下述之申請專利範圍内。 本紙張尺度適用中國國家標準(CNS)A4規格(210χ297公釐)574351 V. Description of the invention (The thickness of the invention can be effectively maintained. In addition, Cong, &, *.,-Can also prevent silicon oxide and the shallow trench isolation structure 2 i 2 from being damaged by the etchant. Please read the precautions on the back before filling this page.) In addition, the thickness of the silicon oxide layer 202 can be effectively improved because the thickness of the oxidized stone layer 202 can be improved. In this way, the oxide: layer 202 can It can be directly used as a sacrificial oxide layer, without the need to first remove the oxide dream layer and then form another sacrificial oxide layer. Not only can reduce the burden on the process, but also improve the reliability of the process. The advantage of the present invention is because of the surname of the present invention The etching agent is connected with every 7 compounds containing water-soluble europium, so it can reach Fudangu a ,, and so on. ”The purpose of this article is to introduce the selection ratio of the Dajin Tianyangnan etchant to the etching of silicon nitride and silicon oxide. ^ The present invention Another advantage is that the application of the etchant of the present invention can effectively improve the etching selection ratio between silicon nitride and silicon oxide, so that after the silicon nitride layer is removed, a pad oxide layer with good thickness uniformity can be obtained. An advantage It is because the thickness of the pad oxide layer is maintained, and a separate sacrificial oxide layer is not required to be manufactured, so the process steps can be simplified and the process cost can be reduced. Another advantage of the present invention is that the shallow trenches can be improved because no additional sacrificial oxide layer is required to be manufactured. The quality of the isolation structure achieves the purpose of improving the reliability and yield of the process. The consumer cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs printed it. As understood by those familiar with this technology, the above is only a preferred embodiment of the present invention. It is not intended to limit the scope of patent application of the present invention; all other equivalent changes or modifications made without departing from the spirit of the present invention should be included in the scope of patent application below. This paper standard applies to Chinese national standards (CNS) A4 size (210 x 297 mm)