五 經濟部智慧財產局員工消費合作社印製 444314 發明說明（/) 詳細說明： 發明之技術領域： 、本發月，有關—種檢驗基板接觸窗内殘留氧化石夕層的 =法特m於—種以高溫氫氧⑽之刻方式檢驗 基板接觸窗内殘留氧化矽層的方法。 發明背景： 按，在積體電路的製程中，接觸窗(c〇ntact H〇|e)的電 阻值是一她4要够數。齡接觸㈣雜值偏高，不 但會使積體電路簡佩率霞，甚至會使元件本身失效 而造成良率下降。造成躺窗的電阻值偏高的原因有許多 種’諸如，屬線過窄、接觸窗的尺寸太小、雜質捧雜浪度 不足、或疋接觸窗内矽基板的表面上有殘留的氧化矽層等 等。大部分上述原因的檢驗都报容易，唯獨基板接觸窗 (Substrate Contact Hole)内殘留氧化矽層的檢驗非常困 難。因為基板接觸窗内殘留氧化矽層的厚度通常僅有數個 A到幾百A之間’顧製程線上的掃描式電子顯微鏡(SEM) 幾乎無法判疋是否有薄氧化石夕層存在。實地檢驗結果的示 意圖请參閱圖一A和圖一B，圖上顯示積體電路製程已在矽 基板上11完成層間介電層12的沉積，並完成開啟接觸窗13 之蝕刻步驟之後的剖面圖，其中圖一A是使用穿透式電子 顯微鏡(TEM)檢驗基板接觸窗内殘留氧化矽層的示意圖， 其結果顯示有一層薄的氧化矽層14殘留在接觸窗内；然而 圖一 B是使用掃描式電子顯微鏡(SEM)檢驗同一接觸窗的結 果’顯示掃描式電子顯微鏡並無法檢驗出該氧化妙層的存 ___III — — — — I - I I I !| 訂·------- '- (請先閱ti-t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（210^2^7公釐）Printed by the Consumers ’Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs 444314 Description of the invention (/) Detailed description: The technical field of the invention: 、 This month, it is related to-a kind of inspection of the residual oxide stone layer in the contact window of the substrate = Fatm in- A method for inspecting a residual silicon oxide layer in a contact window of a substrate in a high-temperature hydrogen-oxygen engraving manner. Background of the invention: According to the integrated circuit manufacturing process, the resistance value of the contact window (contact H0 | e) is one to four. The age contact impurity value is too high, which will not only make the integrated circuit simple and attractive, but also cause the component itself to fail and cause the yield to decrease. There are many reasons for the high resistance value of the window. 'For example, the line is too narrow, the size of the contact window is too small, the impurity wave is not enough, or there is residual silicon oxide on the surface of the silicon substrate in the contact window. Layers and so on. The inspection of most of the above reasons is easy to report, but the inspection of the residual silicon oxide layer in the substrate contact hole is very difficult. Because the thickness of the residual silicon oxide layer in the contact window of the substrate is usually only between several A and several hundred A ', the scanning electron microscope (SEM) on the process line can hardly determine whether a thin oxide layer exists. Refer to Figure 1A and Figure 1B for a schematic diagram of the field test results. The figure shows that the integrated circuit process has completed the deposition of the interlayer dielectric layer 12 on the silicon substrate 11 and the cross-sectional view after the etching step of opening the contact window 13 is completed. Among them, FIG. 1A is a schematic diagram of the residual silicon oxide layer in the contact window of the substrate using a transmission electron microscope (TEM). The result shows that a thin silicon oxide layer 14 remains in the contact window; however, FIG. Scanning electron microscope (SEM) inspection of the same contact window 'shows that the scanning electron microscope can not detect the existence of this wonderful layer of oxide ___III — — — — I-III! | Order · -------' -(Please read the precautions on the ti-t side before filling out this page) This paper size applies to China National Standard (CNS) A4 (210 ^ 2 ^ 7mm)
五、發明說明（> ) 在。 4443 目前實務上用崎驗基板_窗_ -----------裝--------訂· (請先閱讀嘴面之注意事項再填寫本頁) 具是穿透找子麟鏡(TEM)，_異_妨以檢驗出 基板接觸窗内所殘留之數十個A厚的薄氧切層。缺而使 =牙透式電子顯微鏡做為基板朗氧切層的檢 驗工具有下列的缺點： (-)穿透式電子顯微鏡非常昂貴，通常只有故障分 析實驗室有此機台，生產線上無法使用其來立即 反應製程機台之問題。 (二）穿透式電子顯微鏡所適用之試片的製作相當不 易且費通常對-個接觸窗進行穿透式電子顯 微鏡的檢驗要耗費2工作天。 濟 部 智 慧 財 產 局 員 工 消 費 合 作 社 印 製 (二）最嚴重的是，使用穿透式電子顯微鏡做為基板 接觸窗内殘留氧化石夕層的檢驗工具僅能檢驗1至3 個接觸窗（因每一試片的檢驗需費時2工作天）， 而無法對整片晶片進行通盤的檢驗。在無法確定 殘留氧化石夕層之均勻度(Un丨Tormity)的情況之下， 僅檢驗1至3個基板接觸窗並不能確實反應出一片 半導體晶片上所有基板接觸窗的狀況。 因此’發展出一種不需依賴穿透式電子顯微鏡，僅使 用掃插式電子顯微鏡或光學顯微鏡便可進行殘留氧化矽層 檢驗的方法，便顯得非常重要。 本紙張尺度適用争囷國家標準（CNS)A4現格（‘210 X 297公釐） ,4443 1 4 A7 ------- B7 五 經濟部智慧財產局員工消費合作钍印製 發明說明（i ) 發明之簡要說明： 本發明之主要目的是提供一種檢驗基板接觸窗内 氧化矽層的方法。 曼留 ___________ :裝--------訂· - r f靖先閱讀背面之注意事項再填窝本頁) ，發明之次要目的是提供—種以高溫氫氧化钟濕 方式檢驗基板接觸窗喊留氧秘層的方法。 x 本發明揭露—錄驗基板接觸窗内朗氧切層的方 法’適用於積體電路製程已完成層間介電層之沉積，並— 成，啟接_之_步驟之後。本發_重點為利用高= 的乳氧化钾溶液進行祕靠加歸比，接下來只要利： 光學顯微鏡或掃描式電子顯微鏡便可檢驗是否有氧化石夕層 殘留在基板接觸窗内的石夕基板上。而且經 氮氧化钟對不同的介電層（即不同成長方法的氧4匕層= 餘刻率’而由高溫氫氧化娜刻產生 時間’可推算_的氧化㈣的歧。 需 較佳者_L述的檢驗步驟係利用掃描式電子顯微鏡檢 驗所述基板接職的橫剖面，若⑨基板被沿著（111)注 晶祕刻則代表沒有殘留氧化梦層，然而若石夕基板沒有被 兹刻則代鱗述基板接_内有殘㈣氧化發層。 較佳者’上述的檢驗步驟係利用光學顯微鏡或掃描式 電子顯微鏡檢赌述基祕_的絲，若錄板被沿著 (111)結晶祕酬代表沒有殘留氧切層，然而若石夕 基板’又有被似㈣代表該基板接觸窗内有殘留的氧化石夕 層。 本紙張尺度適用巾_家標準（CNS_G &格咖χ4297公變 4443 1 4 A7 五、發明說明（ 圖式說明： 圖-A係使用穿透式電子顯微鏡(TEM)檢驗 留氧化石夕層的示意圖。 ％ 圖-Β是使用掃猫式電子顯微鏡(SEM)檢驗與圖 基板接觸窗的剖面示意圖。 殘 'A相同之 圖二是 本發明中檢驗顧_ f之_氧化石夕層 圖。 _ / 'w的流程 圖三A顯示本發明中在沒有殘留氧化料的情況 高溫氫氧化钾進行濕飯刻的製程剖面圖。’ 圖三B係圖三A的俯視圖。 圖三C顯示本發明在有殘喊切層的情况之下， 氫氧化許進行濕蚀刻的製程剖面圖。 圖三D係圖三c的俯視圖。 以 以高溫 II ------ -·裝--------訂- (請先閱讀臂面之注意事項再填寫本頁) 圖號說明： 11-矽基板 13-接觸窗 31-砍基板 33-接觸窗 35-矽原子 12-層間介電層 14-薄的氧化矽層 32-層間介電層 （111)結晶面 36-殘留的氧化矽層 接觸iirf露—種以高溫氫氧化鉀難财式檢驗基板 程已H ^切料紐°本發_躲龍電路製 凡胃間介電層之沉積，並完成開啟接觸窗之侧步 錢張尺料 (210 X 297 公髮） 444314 A7 五、發明說明（S ) ^後’藉由—道高溫氫氧化鉀溶液之濕侧_助以加 二匕么接下來”要利用光學顯微鏡或是掃描式電子顯微 鏡便可檢驗衫有氧化韻劾在基板接_ _雜板 上。 首先叫參閱®— ’為本發明檢驗基板鋪窗之殘留氧 化石^層的机程圖，適用於積體電路製程已完成層間介電層 的/儿積，並;^成開啟接觸窗之偏彳步驟之後。在檢驗程序 開始之後21 ’以高賊氧化鉀溶驗行刻22，之後並 利用光學顯微锻是掃描式電子酿舰行檢驗23，若石夕 基$被姓刻則代表基板接觸窗内沒有殘留氧化石夕層24，然 而右石夕基板沒有被敍刻則代表該基板接觸窗内有殘留氧化 矽層25。 /所述濕飯刻是利用重量百分比，〇%的氫氧化钟溶液進 行’反應溫度介於8〇至1〇〇。〔之間，反應時間介於5秒至7 分鐘之間。其中最佳的反應溫度為赃，而最佳的反應時 間約為25秒。 接下來說明本發明利用高溫氫氧化卸濕侧方式檢驗 殘留氧化矽層的原理，請參考圖三A至圖三D，其中圖三A 顯示在沒有殘留氧化矽層的情況之下，以高溫氫氧化鉀溶 液進行濕蝕刻的製程剖面圖，而圖三已則顯示其俯視圖； 另一方面’圖三C顯示在矽基板有殘留氧化矽層的情況之 下’以高溫氫氧化鉀溶液進行濕蝕刻的製程剖面圖，而圖 則顯示其俯視圖。根據文獻Sj|jc〇n processing for the VLSI ERA，Volume II ρ·68中得知高溫氫氧化鉀溶液對Si02 {請先閱讀背面之注意事項再填寫本頁) I I n a— n n I I I . 經濟部智慧財產局員工消費合作社印製 不，、又、用中國國家標準（CNS)A4規格（210 x 2$7公餐） 4443 1 4 經濟部智慧財產局員工消費合作社印製 A7 B7 五、發明說明（L) 的蝕刻率極慢，而對Si(111)結晶面的蝕刻率極快。因此當 積體電路製程已在一矽基板31上沉積層間介電層32，並完 成開啟接觸窗33之蝕刻步驟之後，若矽基板31的表面沒有 殘留氧化石夕層，則尚溫氫氧化钟會沿著（111 )結晶面34 對矽基板31進行蝕刻，如圖三a及圖三B所示，其中圖三A 中的小圓圈代表一個個矽原子35 ;而另一方面，若矽基板 31的表面有殘留的氧化矽層36，則高溫氫氧化鉀溶液對該 氧化矽層36幾乎沒有蝕刻作用，如圖三〇所示’而且圖三 D中也不復見（111)結晶面34。 在利用高溫之氫氧化鉀溶液進行濕蝕刻之後，便可利 用光學顯微鏡或是掃描式電子顯微鏡進行檢驗。其中晶片 之橫剖面可儀掃賊電子_舰行檢驗，絲基板被 沿著（111)結晶面侧（如圖三八）則代表沒有殘留氧化 石夕層，然而若；5夕基板沒有被飯刻（如圖三C)則代表該基 板接觸窗内有殘留氧化石夕層。在另一方面，晶片表面可分 別利用掃描式電子顯微鏡和光學顯微鏡進行檢驗，若矽基 板被沿著（111)結晶面蝕刻（如圖三B)則代表沒有殘留 氧化石夕層，然而右石夕基板沒有被钱刻（如圖三D)則代表 該基板接觸窗内有殘留氧化矽層。 綜上所述，本發明所揭露的檢驗技術具有下列的優 點： 1.可以快速地檢驗基板接觸窗内的基板上是否有殘留 之氧化矽層。 2·本發明之方法的產量極南，可在2小時之内完成一 本紙張尺度剌 + ®iiiTT6NS)A4 (210 X 2^7 in — — — — — — — 1·裝 ----I 訂·--) 1111 (請先閲讀臂面之注意事項再填寫本頁) 4443145. Description of the invention (>) 4443 At present, it is practically used to inspect the substrate _ window _ ----------- install -------- order (please read the precautions of the mouth first and then fill out this page) Looking through the TEM lens, it is possible to check the dozens of A-thick oxygen-cutting layers remaining in the substrate contact window. The lack of = tooth-through electron microscope as the inspection tool for the substrate oxygen layer has the following shortcomings: (-) Transmission electron microscope is very expensive, usually only the fault analysis laboratory has this machine, which cannot be used on the production line It comes to immediately reflect the problem of the process machine. (2) It is quite difficult and expensive to make a test piece suitable for a transmission electron microscope. It usually takes 2 working days to inspect a contact window for a transmission electron microscope. Printed by the Consumer Cooperative of the Intellectual Property Bureau of Jibei (2) The most serious is that the inspection tool using a transmission electron microscope as the residual oxide layer in the contact window of the substrate can only inspect 1 to 3 contact windows (because The inspection of a test piece takes 2 working days), and the entire wafer cannot be inspected in a comprehensive manner. In the case that the uniformity (Un 丨 Tormity) of the residual oxide layer cannot be determined, the inspection of only 1 to 3 substrate contact windows cannot accurately reflect the condition of all substrate contact windows on a semiconductor wafer. Therefore, it is very important to develop a method that does not rely on a transmission electron microscope and can perform a residual silicon oxide layer inspection using only a scanning electron microscope or an optical microscope. This paper size is applicable to National Standards (CNS) A4 ('210 X 297 mm), 4443 1 4 A7 ------- B7 Five Ministries of Economic Affairs, Intellectual Property Bureau, Consumption Cooperation, Printed Invention Description ( i) Brief description of the invention: The main object of the present invention is to provide a method for inspecting a silicon oxide layer in a substrate contact window. Manliu ___________: Install -------- Order ·-rf Jing first read the precautions on the back and then fill the nest page), the secondary purpose of the invention is to provide-a method of inspecting the substrate by the high temperature, hydrogen and humidity method Contact the window to shout the method of oxygen retention. x The present invention discloses that the method of recording oxygen-cutting layer in the contact window of the substrate is applicable to the deposition of the interlayer dielectric layer after the integrated circuit process has been completed, and is completed after the ___ step. The focus of this issue is to use the potassium lactate solution with high = to increase the secret ratio. Next, as long as the benefits are as follows: An optical microscope or a scanning electron microscope can be used to check whether there is a stone oxide layer remaining in the contact window of the substrate. On the substrate. Moreover, the different dielectric layers (ie, the oxygen 4 d layer of different growth methods = the residual rate) and the time generated by the high-temperature hydroxide etching can be used to estimate the difference of ytterbium oxide by the nitrogen oxidizing bell. Need better _ The inspection procedure described in L is to use a scanning electron microscope to inspect the cross-section of the substrate. If the substrate is cast along the (111) ingot, it means that there is no residual oxide layer. However, if the Shi Xi substrate is not covered, There is a residual oxide layer inside the substrate, which is engraved on the scale. It is better that the above-mentioned inspection step is to use a light microscope or a scanning electron microscope to inspect the wire that describes the substrate. If the recording board is moved along (111 ) The crystalline secret reward means that there is no residual oxygen cutting layer, but if the Shi Xi substrate 'has been shown to represent a residual oxide stone Xi layer in the contact window of the substrate. This paper is applicable to towels_Home Standards χ4297 public variable 4443 1 4 A7 V. Description of the invention (Illustration of the drawings: Figure-A is a schematic diagram of the oxidized stone oxide layer using a transmission electron microscope (TEM).% Figure-B is a scanning cat electron microscope ( (SEM) Inspection of the section of the contact window with the substrate Schematic diagram. Residual 'A is the same. Figure 2 is a diagram of the oxidized stone layer of Gu_f in the present invention. Flowchart 3A of' / w shows that high temperature potassium hydroxide is carried out in the present invention without residual oxide. Sectional view of the process of wet rice engraving. 'Fig. 3B is a top view of Fig. 3A. Fig. 3C shows a cross-sectional view of the wet etching process of the present invention with a residual cutting layer. Fig. 3D This is the top view of Figure 3c. With high temperature II -------· install -------- order-(Please read the precautions of the arm surface before filling this page) Figure number description: 11- Silicon substrate 13-contact window 31-cut substrate 33-contact window 35-silicon atom 12-interlayer dielectric layer 14-thin silicon oxide layer 32-interlayer dielectric layer (111) crystal plane 36-residual silicon oxide layer contact iirf—a kind of difficult-to-finish substrate inspection with high-temperature potassium hydroxide. The cutting process is H ^ cutting material ° This hair _ hide Long Circuit made of the deposition of the dielectric layer between the stomach, and complete the side step of opening the contact window (210 X 297) 444314 A7 V. Description of the invention (S) After the 'by the wet side of the high-temperature potassium hydroxide solution _ help to add two daggers next' You can use an optical microscope or a scanning electron microscope to check that the shirt is oxidized on the substrate _ _ miscellaneous board. The first is referred to ®-'This is a machine diagram of the inspection of the residual oxide stone layer on the substrate window, It is suitable for the integrated circuit manufacturing process after the completion of the interlayer dielectric layer, and after the bias step of opening the contact window. After the start of the inspection procedure 21 'use high potassium oxide solution test 22, and then The use of optical micro-forging is a scanning electronic brewing inspection23. If Shi Xiji is engraved with the surname, it means that there is no residual oxidized stone layer 24 in the contact window of the substrate. There is a residual silicon oxide layer 25 in the contact window. / The wet meal engraving is carried out by using a weight percent of a 0% hydroxide hydroxide solution for a 'reaction temperature ranging from 80 to 100. [In between, the reaction time is between 5 seconds and 7 minutes. Among them, the optimal reaction temperature is 赃, and the optimal reaction time is about 25 seconds. Next, the principle of the present invention for testing the residual silicon oxide layer by using the high-temperature hydroxide dehumidifying side method is described. Please refer to FIG. 3A to FIG. 3D, where FIG. 3A shows the case where there is no residual silicon oxide layer. A cross-sectional view of the process of wet etching of a potassium oxide solution, and FIG. 3 has shown a plan view thereof; on the other hand, FIG. 3C shows a wet etching with a high-temperature potassium hydroxide solution in the case where a silicon substrate has a residual silicon oxide layer. Section view of the process, and the figure shows its top view. According to the literature Sj | jc〇n processing for the VLSI ERA, Volume II ρ · 68, we know that the high-temperature potassium hydroxide solution for Si02 (Please read the precautions on the back before filling this page) II na— nn III. Ministry of Economic Affairs Wisdom Not printed by the Consumer Cooperative of the Property Bureau, but also using the Chinese National Standard (CNS) A4 specification (210 x 2 $ 7 public meals) 4443 1 4 Printed by the Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs A7 B7 V. Invention Description (L ), The etching rate is very slow, and the etching rate on the Si (111) crystal plane is extremely fast. Therefore, after the integrated circuit manufacturing process has deposited the interlayer dielectric layer 32 on a silicon substrate 31 and completed the etching step of opening the contact window 33, if there is no residual oxide layer on the surface of the silicon substrate 31, the temperature is still high. The silicon substrate 31 will be etched along the (111) crystal plane 34, as shown in FIGS. 3a and 3B, where the small circles in FIG. 3A represent silicon atoms 35; on the other hand, if the silicon substrate There is a residual silicon oxide layer 36 on the surface of 31, and the high-temperature potassium hydroxide solution has almost no etching effect on the silicon oxide layer 36, as shown in FIG. 30 ', and (111) the crystal plane 34 is no longer seen. . After wet etching using a high-temperature potassium hydroxide solution, inspection can be performed using an optical microscope or a scanning electron microscope. The cross-section of the wafer can be inspected by electronic scanners. The silk substrate is along the (111) crystal plane side (as shown in Figure 38), which means that there is no residual oxide layer, but if; The engraving (as shown in Figure 3C) indicates that there is a residual oxide layer in the contact window of the substrate. On the other hand, the surface of the wafer can be inspected with a scanning electron microscope and an optical microscope. If the silicon substrate is etched along the (111) crystal plane (as shown in Figure 3B), it means that there is no residual oxide layer, but the right stone Even if the substrate is not engraved with money (as shown in Figure 3D), it means that there is a residual silicon oxide layer in the contact window of the substrate. In summary, the inspection technology disclosed in the present invention has the following advantages: 1. It can quickly inspect whether there is a residual silicon oxide layer on the substrate in the substrate contact window. 2. The output of the method of the present invention is extremely south, and a paper size can be completed within 2 hours. Order ·-) 1111 (Please read the precautions of the arm surface before filling in this page) 444314
整片晶片的檢驗。 3_利用掃描式電子酿鏡和光學臓餅可進行檢 驗’不需要昂責的檢驗設備，也賴進行繁複的樣 品馈製。 4.進行-:嫌驗步毅可完成U上铸基板接觸 窗的檢驗。 5·叙實驗可得知高溫氩氧化卸料⑽介電層（即不 同成長方法的氧化層）_刻率’而由高溫氮氧化 鉀餘刻產生Si(111)银刻面所需之時間，可推算殘 留的氧化矽層的厚度。 ^ 本發明係透過具體實施例加以敘述，說明本發明的原 則和精神，應可瞭解本發明並不侷限於所揭露的具體實施 例，因此，在本發明之原則和範圍底下所作任何相關細= 上之變化，都應視為本發明的進一步實施例。 <:請先閲讀嘴面之注意事項再填寫本頁} -裝--------訂---------,^ 經濟部智慧財產局員工消費合作社印製 適 度 尺 張 紙 I本 格 |規 -4 -A ls) (CN 準 標 ^ t297Inspection of whole wafer. 3_ Inspection can be performed with scanning electronic brewing mirrors and optical cakes ’No heavy inspection equipment is required, and complicated sample feeding is also required. 4. Proceed with-: Inspecting Buyi can complete the inspection of the contact window of the cast substrate on U. 5. · Symptoms can be obtained from the high temperature argon oxidation unloading ⑽ dielectric layer (that is, the oxide layer of different growth methods) _ engraving rate 'and the time required to produce Si (111) silver facet from high temperature potassium nitrate. The thickness of the remaining silicon oxide layer can be estimated. ^ The present invention is described through specific embodiments to explain the principles and spirit of the present invention. It should be understood that the present invention is not limited to the specific embodiments disclosed. Therefore, any relevant details made under the principles and scope of the present invention = The above changes should be regarded as further embodiments of the present invention. <: Please read the precautions before filling in this page} -Install -------- Order ---------, ^ Printed by the Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs Sheet of paper I standard case | Regulation-4 -A ls) (CN standard ^ t297