經濟部中央標準局員工消費合作社印裝 I3477si 3655twf.doc/006 五、發明説明（丨） 本發明是有關於一種擺盪曲線（Swing Curve)的量測方 法，且特別是有關於一種光阻（Photoresist)層反射率 (Reflectance)對光阻厚度之擺盪曲線的量測方法。 微影（Photolithography)是整個半導體製程中，最舉足 輕重的步驟之一。凡是與金屬氧化半導體（Metal Oxide Semiconductor, MOS)元件相關的，如：各層薄膜的圖案 (Pattern)及雜質（Dopants)的區域，都是由微影步驟來決定 的。而半導體製程通常是以所需要經過的微影次數，或是 所需要的光罩(Mask)數量，來表示其難易程度。此外，半 導體元件積集度(Integration)是否能繼續提昇，向更小的線 寬（Line-Width)發展，亦端賴微影製程的發展是否順利而 定。 由於在微影製程中，是以“光”做爲曝光步驟的曝光 來源，因此會產生一種稱爲駐波（Standing Wave)的現象， 導致光阻上轉移圖案之線寬產生改變，進而影響後續的製 程，因此必須對於光阻圖案線寬與光阻厚度之間的關係加 以了解。 光阻層上圖案之線寬與光阻層厚度之間的關係，可以 藉由光阻層不同物理特性對光阻層厚度之擺邊曲線的分析 而瞭解。在微影製程中，光阻上圖案的線寬對光阻厚度之 擺盪曲線是用以決定製程中光阻層厚度的重要特徵之一。 此種擺盪曲線顯示光阻經顯影後圖案之線寬，將隨著光阻 之厚度呈現出振盪波形。藉由擺盪曲線可以界定出後續製 程所需線寬相對應之光阻層較佳厚度範圍，以利後續製程 本紙張尺度適用中國國家標準（CNS ) A4規格（210X 297公釐） f讀先閱讀背面之注意事項再填寫本頁} 裝 經濟部中央標準局員工消费合作社印製 43477^ 3655twf.doc/006 Λ 7 五、發明説明（>) 之進行。 請參照第1圖，其所繪示的是習知一種關鍵尺寸 (Critical Dimension, CD)擺盪曲線量測方法之流程圖。請參 照第1圖之步驟10，首先提供半導體基底，並在其上形成 光阻層。其次，請參照第1圖之步驟12，使用微影機台上 之步進機（Stepper)對光阻層進行曝光、顯影。再參照第1 圖之步驟14，對光阻層進行厚度量測，並使用關鍵尺寸-掃瞄式電子顯微鏡（Critical Dimension-Scanning Electronic Microscope, CD-SEM)，對光阻層上圖案之關鍵尺寸進行量 測，再描繪出光阻層上圖案關鍵尺寸對光阻層厚度之關鍵 尺寸擺盪曲線(CD Swing Curve)。量測所需之操作時間大於 20小時。 請參照第2圖，其所繪示的是習知一種啓始能量 (Threshold Energy，Eth)擺盪曲線量沏J方法之流程圖。請參 照第2圖之步驟20，首先提供半導體基底，並在其上形成 光阻層。其次，請參照第2圖之步驟22，使用微影機台上 之步進機對光阻層進行曝光、顯影。再參照第2圖之步驟 24，對光阻層進行厚度量測，並對光阻層進行啓始能量之 量測，再描繪出光阻層啓始能量對光阻層厚度之啓始能量 擺盪曲線（Eth Swing Curve)。量測所需之操作時間大於12 小時。 然而習知所採用的方法，都必須使用微影機台之步進 機來進行微影製程。於光阻層經曝光、顯影之後，再進行 光阻層物理性質量測，描繪出擺盪曲線，其步驟較爲繁複， 4 (讀先鬩讀背面之注意事項再填寫本頁) 裝_ 訂 本紙張尺度適用中國國家標準（CNS ) Α4規格（210X 297公釐） 4347Ta 365 5twf.doc/〇〇6 五、發明説明（$ ) 量測所需之時間較長。 因此本發明的主要目的就是在提供一種擺盪曲線的量 測方法，可以節省顯影液、以及步進機與關鍵尺寸-掃瞄 式電子顯微鏡的使用時間，進而縮短量測及製程所需時 間，降低製程所需之成本並提高效率。 根據本發明之上述目的，提出一種擺盪曲線的量測方 法。進行光阻層反射率及光阻層厚度之測量’可以得到與 關鍵尺寸擺盪曲線、啓始能量擺盪曲線類似的結果，即光 阻層反射率對光阻層厚度之反射率擺盪曲線（Reflectance Swing Curve)，以決定製程所需之光阻層的厚度。此法= 需要進行微影製程，因此可節省顯影液、以及步進機 鍵尺寸-掃瞄式電子顯微鏡的操作時間。 爲讓本發明之上述和其他目的、特徵、和優點能襄明 顯易懂’下文特舉一較佳實施例，並配合所附圖示’作# 細說明如下： 圖示之簡單說明： 、私 第1圖繪示習知一種關鍵尺寸擺盪曲線量測方法之_ sa tsi · 程圖* 經濟部中央標準局員工消費合作社印製 --------ί 裝---- (請先聞讀背面之注意事項再填释本頁) 第2圖繪示習知一種啓始能量擺盪曲線量測方法之 程圖； 第3圖繪示依照本發明之一較佳實施例，一權反射革 擺盪曲線量測方法之流程圖；以及 β々靡镇 第4圖繪示光阻層不同物理特性對光阻層瘳度 曲線示意圖。 5 一 本紙張尺度適用中國國家橾準（CNS ) A4規格（210X297公釐） 經濟部中央標準局員工消費合作社印裝 434774 3655twf.doc/006 五、發明説明（羊） 圖示之標記說明： 10〜i4:習知關鍵尺寸擺盪曲線之量測步驟 20〜24:習知啓始能量擺盪曲線之量測步驟 30〜32 :應用本發明之反射率擺盪曲線之量測步驟 40 :反射率擺盪曲線 42 :啓始能量擺盪曲線 44 :關鍵尺寸擺盪曲線 實施例 請參照第3圖，其所繪示的是依照本發明之一較佳實 施例，一種反射率擺盪曲線量測方法之流程圖。請參照第 3圖之步驟30，首先提供複數個半導體基底，並在這些基 底上分別形成不同厚度之光阻層，光阻層厚度之分佈係依 照製程之需要所決定，其中光阻層的材料包括正光阻及負 光阻，而且這些光阻層皆未進行微影製程，亦即未經曝光、 顯影步驟。其次，請參照第3圖之步驟32，對光阻層進行 厚度量測，並使用反射率量測工具，對不同厚度之光阻層 進行量測，藉以得到不同厚度光阻層之反射率，再描繪出 光阻層反射率對光阻層厚度之反射率擺盪曲線。量測所需 之操作時間約爲4小時。 由於在微影製程中，以光做爲曝光步驟之光源，會產 生駐波的現象。在進行曝光時，部份沒有被光阻吸收的光， 經反射之後，與入射的光波產生建設性（Constructive)及破 壞性（Destructive)的干涉（Interference)，形成所謂的駐波， 使得光阻層接受曝光的強度不均勻，導致光阻上轉移圖案 6 (請先閱讀背面之注^*項再填寫本頁) 装' 訂 本紙張尺度適用中國國家標準（CNS ) 規格（210X297公釐） 經濟部中央標準局員工消費合作社印裝 434774 3655twf.doc/006 五、發明説明（s ) 之線寬產生改變，進而影響後續的製程。因此藉由所得之 反射率擺盪曲線，可以界定出具有最低反射率之光阻層厚 度範圍，避免曝光產生駐波與干涉、以及轉移圖案線寬:改 變等現象，以利後續製程之進行。 請參照第4圖，其所繪示的是光阻層不同物理性質對 光阻層厚度之擺盪曲線示意圖。其中’橫軸所表示的是光 阻層之厚度，而縱軸所表示的則是光阻層不同之物理性 質，包括反射率、啓始能量關鍵尺寸及關鍵尺寸等。線40 所表示的是光阻層之反射率擺盪曲線；線42所表示的是 光阻層之啓始能量擺盪曲線；以及線44所表示的是光阻 層之關鍵尺寸擺盪曲線。 由上述本發明較佳實施例可知’本發明之特徵是對於 基底表面之光阻層直接進行反射率量測’而不需要先進行 微影製程。請參照表1，其所列示的是本發明與習知之擺 盪曲線量測方法所需使用之工具與操作時間。 由上述本發明較佳實施例可知，應用本發明’由於不 需要進行微影製程，亦即不需經過曝光、顯影等步驟’因 此可以節省顯影液、以及步進機與關鍵尺寸-掃瞄式電子 顯微鏡的使用時間，進而縮短量測及製程所需時間’降低 製程所需之成本並提高效率。 雖然本發明已以一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 神和範圍內，當可作各種之更動與潤飾’因此本發明之保 護範圍當視後附之申請專利範圍所界定者爲準。 7 (請先閱讀背面之注意事項再填寫本頁) 裝·Printed by the Consumer Cooperatives of the Central Standards Bureau of the Ministry of Economic Affairs I3477si 3655twf.doc / 006 V. Description of the Invention (丨) The present invention relates to a method for measuring a swing curve, and in particular to a photoresist. ) The measurement method of the reflectance of the layer to the swing curve of the thickness of the photoresist. Photolithography is one of the most important steps in the entire semiconductor process. All areas related to Metal Oxide Semiconductor (MOS) elements, such as the pattern and impurities of each layer of thin film, are determined by the lithography step. The semiconductor process usually uses the number of lithography or the number of masks to indicate the difficulty. In addition, whether the integration of semiconductor components can continue to improve and develop to a smaller line-width depends on whether the development of the lithography process is smooth. In the lithography process, "light" is used as the exposure source of the exposure step, so a phenomenon called standing wave will occur, which will cause the line width of the transfer pattern on the photoresist to change, which will affect subsequent Process, it is necessary to understand the relationship between the line width of the photoresist pattern and the thickness of the photoresist. The relationship between the line width of the pattern on the photoresist layer and the thickness of the photoresist layer can be understood by analyzing the swing curve of the thickness of the photoresist layer with different physical characteristics of the photoresist layer. In the photolithography process, the swing of the line width of the pattern on the photoresist to the thickness of the photoresist is one of the important characteristics used to determine the thickness of the photoresist layer in the process. This swing curve shows that the line width of the pattern after the photoresist is developed will show an oscillating waveform with the thickness of the photoresist. The swing thickness curve can be used to define the preferred thickness range of the photoresist layer corresponding to the line width required for subsequent processes, so as to facilitate subsequent processes. The paper size applies the Chinese National Standard (CNS) A4 specification (210X 297 mm). F Read first Note on the back, please fill out this page again} Installed by the Consumers Cooperative of the Central Bureau of Standards of the Ministry of Economic Affairs to print 43477 ^ 3655twf.doc / 006 Λ 7 5. The description of the invention (>). Please refer to FIG. 1, which shows a flowchart of a method for measuring a critical dimension (CD) swing curve. Please refer to step 10 in Fig. 1. First, a semiconductor substrate is provided, and a photoresist layer is formed thereon. Secondly, please refer to step 12 in FIG. 1, and use a stepper on the lithography machine to expose and develop the photoresist layer. Referring to step 14 in FIG. 1, the thickness of the photoresist layer is measured, and a critical dimension-scanning electronic microscope (CD-SEM) is used to determine the key dimensions of the pattern on the photoresist layer. Measure and draw the CD Swing Curve, which is the critical dimension of the pattern on the photoresist layer versus the thickness of the photoresist layer. The measurement takes more than 20 hours. Please refer to FIG. 2, which shows a flowchart of a conventional method for preparing a swing energy of a Threshold Energy (Eth) swing curve. Please refer to step 20 in Fig. 2. First, a semiconductor substrate is provided, and a photoresist layer is formed thereon. Next, please refer to step 22 in FIG. 2, and use a stepper on the lithography table to expose and develop the photoresist layer. Referring to step 24 in FIG. 2 again, measure the thickness of the photoresist layer, and measure the initial energy of the photoresist layer, and then draw the swing curve of the initial energy of the photoresist layer to the thickness of the photoresist layer. (Eth Swing Curve). The measurement requires more than 12 hours of operation time. However, the methods used in the conventional methods must use the stepper of the lithography machine to perform the lithography process. After the photoresist layer is exposed and developed, the physical quality of the photoresist layer is measured, and the swing curve is drawn. The steps are more complicated. 4 (read the precautions on the back and then fill out this page). Paper size applies Chinese National Standard (CNS) A4 specification (210X 297 mm) 4347Ta 365 5twf.doc / 〇〇6 5. Description of invention ($) The time required for measurement is longer. Therefore, the main purpose of the present invention is to provide a method for measuring the swing curve, which can save the use time of the developing solution, the stepper and the key size-scanning electron microscope, thereby shortening the time required for measurement and manufacturing, and reducing Costs required for manufacturing processes and increased efficiency. According to the above object of the present invention, a method for measuring a swing curve is proposed. Performing the measurement of the photoresist layer reflectance and photoresist layer thickness' can obtain results similar to the critical dimension swing curve and the initial energy swing curve, that is, the reflectance swing curve of the photoresist layer reflectivity versus the photoresist layer thickness. Curve) to determine the thickness of the photoresist layer required for the manufacturing process. This method = requires a lithography process, which saves the developer time and the operation time of the stepper key size-scanning electron microscope. In order to make the above and other objects, features, and advantages of the present invention obvious and comprehensible, a preferred embodiment is exemplified below, and the accompanying drawings are made as follows. A detailed description of the drawings is as follows: Figure 1 shows a conventional method for measuring the swing curve of key dimensions. Sa tsi · Cheng Tu * Printed by the Consumer Cooperatives of the Central Standards Bureau of the Ministry of Economic Affairs Note on the back of the reading and refill this page) Figure 2 shows the process diagram of a conventional method for measuring the energy swing curve; Figure 3 shows a right reflection according to a preferred embodiment of the present invention Flow chart of the measurement method of the swing curve; and Figure 4 of β々ome town shows the schematic diagram of the photoresist layer thickness curve with different physical characteristics of the photoresist layer. 5 A paper size applies to the Chinese National Standard (CNS) A4 (210X297 mm) Printed by the Consumer Cooperatives of the Central Standards Bureau of the Ministry of Economic Affairs 434774 3655twf.doc / 006 V. Description of the invention (sheep) Symbol description of the diagram: 10 ~ I4: Know the measurement steps of the key size swing curve 20 ~ 24: Know the measurement steps of the energy swing curve 30 ~ 32: Apply the measurement step 40 of the reflectance swing curve of the present invention: Reflectance swing curve 42: Initial energy swing curve 44: Key size swing curve embodiment Please refer to FIG. 3, which shows a flowchart of a method for measuring the reflectance swing curve according to a preferred embodiment of the present invention. Please refer to step 30 in FIG. 3, firstly provide a plurality of semiconductor substrates, and respectively form photoresist layers with different thicknesses on these substrates. The thickness distribution of the photoresist layer is determined according to the needs of the process. The material of the photoresist layer It includes positive photoresist and negative photoresist, and these photoresist layers have not been lithographically processed, that is, they have not been exposed or developed. Secondly, please refer to step 32 in FIG. 3 to measure the thickness of the photoresist layer, and use the reflectance measurement tool to measure the photoresist layer with different thickness to obtain the reflectance of the photoresist layer with different thickness. Then draw the reflectance swing curve of the reflectivity of the photoresist layer to the thickness of the photoresist layer. The measurement takes about 4 hours. In the photolithography process, light is used as the light source of the exposure step, and a standing wave phenomenon occurs. During exposure, part of the light that is not absorbed by the photoresist, after reflection, produces constructive and destructive interference with the incident light wave, forming a so-called standing wave, making the photoresist The intensity of the layer receiving exposure is uneven, leading to the photoresist transfer pattern 6 (Please read the note ^ * on the back before filling this page). The size of the bound paper is applicable to the Chinese National Standard (CNS) specifications (210X297 mm). Printed by the Consumer Standards Cooperative of the Central Standards Bureau of the Ministry of Foreign Affairs 434774 3655twf.doc / 006 V. The line width of the invention description (s) has changed, which in turn affects subsequent processes. Therefore, by using the obtained reflectance swing curve, the thickness range of the photoresist layer having the lowest reflectance can be defined, avoiding standing waves and interference caused by exposure, and transferring the pattern line width: change, etc., to facilitate subsequent processes. Please refer to FIG. 4, which shows a schematic diagram of a swing curve of the photoresist layer with different physical properties. Among them, the horizontal axis indicates the thickness of the photoresist layer, and the vertical axis indicates the different physical properties of the photoresist layer, including the reflectivity, the critical size of the initial energy, and the critical size. Line 40 shows the reflectivity swing curve of the photoresist layer; line 42 shows the initial energy swing curve of the photoresist layer; and line 44 shows the key size swing curve of the photoresist layer. According to the above-mentioned preferred embodiments of the present invention, it is known that the feature of the present invention is that the reflectance measurement is directly performed on the photoresist layer on the surface of the substrate, without performing a lithography process first. Please refer to Table 1, which lists the tools and operation time required for the swing curve measurement method of the present invention and the conventional method. It can be known from the above-mentioned preferred embodiments of the present invention that the application of the present invention 'because no lithographic process is required, that is, no steps such as exposure and development are needed', so the developer solution can be saved, and the stepper and the key size-scanning type can be saved. The use time of the electron microscope, thereby shortening the time required for measurement and manufacturing process' reduces the cost required for the manufacturing process and improves the efficiency. Although the present invention has been disclosed as above with a preferred embodiment, but it is not intended to limit the present invention. Anyone skilled in the art can make various changes and decorations without departing from the spirit and scope of the present invention. The scope of protection of the invention shall be determined by the scope of the attached patent application. 7 (Please read the notes on the back before filling this page)
，1T 本紙張尺度適用中國國家標準·{ CNS ) Α4規格（210X25)7公釐〉 434774 五、發明説明（έ) 經濟部中央標率局員工消費合作社印製 表1不同擺盪曲線量測方法所需使用之具器與操作時間 關鍵尺寸擺盪 曲線量測方法 啓始能量擺盪 曲線量測方法 反射率擺盪曲 線量測方法 微影機台Χ2次 微影機台Χ2次 微影機台 步進機Χ2次 步進機Χ2次 ————— 所需使用 厚度量測工具 厚度量測工具 厚度量測工具 之器具 關鍵尺寸-掃瞄式電子 顯微鏡 啓始能量量測 工具 反射率量測 丁具 1 操作時間 大於20小時 大於12小時 約爲4小時 δ (請先聞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 ) Α4規格（210X 297公釐）， 1T This paper size applies the Chinese national standard. {CNS) A4 size (210X25) 7mm> 434774 V. Description of the invention (Ruled) Printed by Table 1 of different swing curve measurement methods by the Central Consumer Bureau of the Ministry of Economic Affairs and the Consumer Cooperatives. Tools and Operating Time Critical Dimension Swing Curve Measurement Method Start Energy Swing Curve Measurement Method Reflectance Swing Curve Measurement Method Lithography Machine X 2 Times Lithography Machine X 2 Times Lithography Machine Stepper X 2 Secondary stepper × 2 times —————— Need to use thickness measuring tool Thickness measuring tool Thickness measuring tool Apparatus Key dimensions-Scanning electron microscope Start energy measuring tool Reflectance measuring tool 1 Operation Time is more than 20 hours and more than 12 hours is about 4 hours δ (Please read the precautions on the back before filling in this page) This paper size applies the Chinese National Standard (CNS) Α4 specification (210X 297 mm)