200423194200423194
發明說明 (發明說明應敘明：發明所屬之技術領域、先前技術、內容、實施方式及圖式簡單說明) (一） 發明所屬之枝術領域 本發明有關於「半導體處理裝置之藥液濃度控制裝置 」，在半導體處理裝置，既保持固定的處理用藥液的濃度 ，又維持半導體處理上必須的藥液液面高度。 (二） 先前枝術 於濕式洗滌站等的半導體處理裝置，由於從處理槽搬 出晶圓以及藥液的蒸發等，導致或者藥液的濃度產生變化 、或者液量減少。因此，必須定期補充藥液以維持藥液的 濃度、液量。 第5圖顯示習知「半導體處理裝置之藥液濃度控制裝 置」的方塊圖。如第5圖所示，爲了維持藥液的濃度以及 液面的高度，以濃度計7測定藥液的濃度。補充控制裝置 40檢查濃度計7之濃度數據是否在基準濃度範圍之內，以 選擇基準濃度範圍內時及基準濃度範圍外時個別的補充設 定値，對補充部2 8的補充泵（未圖示）輸出信號，以進行藥 液的補充。第5圖顯示的「半導體處理裝置之藥液濃度控 制裝置」，形成一濃度回饋控制系統，將濃度計7所測定 的濃度數據與基準濃度範圍相比較，控制藥液的濃度在基 準濃度範圍之內。 藥液之補充控制如第6 _所示，藉由補充控制裝置4 0 內藏會產生固定週期的補充間隔計時器，及與補充間隔計 一 6 - 200423194 時器同步起動的各藥液的補充計時器，來補充定量的藥液 。又，第6圖顯示3種（A藥液、B藥液、C藥液）藥液的補 充控制的時序圖。 如第6圖所示，補充控制裝置40的補充間隔計時器的 信號，起動了 A藥液補充計時器、b藥液補充計時器、及C 藥液補充計時器。A藥液補充計時器的計時器時間爲τ 1，B 藥液補充計時器的計時器時間爲T2，C藥液補充計時器的 計時器時間爲T 3，各藥液所備有之補充泵在τ 1、T 2、T 3 ^ 的時間內運轉，以補充固定量的藥液。該藥液補充計時器 的時間按濃度而定，例如，A藥液濃度高於基準濃度範圍 、B藥液濃度低於基準濃度範圍時，A藥液選擇小補充的 設定値、B藥液選擇大補充的設定値，加以補充。似此， 習知之半導體處理裝置，爲維持藥液的濃度，以事先設定 的固定量的藥液補充之。 (三）發明內容： 發明所欲解決的課題 ❿ 然而，藉由比較濃度計之濃度數據與目標値之基準濃 度範圍，習知補充控制裝置40所爲之藥液之補充控制，由 於藥液的混合時間及濃度計的測定時間的影響’如第7圖 所示，t = 0補充藥液後，到t = m2確定濃度數據（P)，產 生了濃度回饋控制系統裏的遲延時間m 2 (圖示於第8圖）。 因此，如第8圖所示，欲控制藥液的濃度於基準濃度 範圍內時，因遲延時間m2的影響’或超過基準濃度範圍的 上限値，或低於基準濃度範圍的下限値’濃度變得零散。 - Ί - 200423194 同樣地，即使是PID (比例•積分•微分）控制的場合，由於 遲延時間m2的影響恐也不能高精度地控制濃度。藥液的濃 度變動，使得洗滌、蝕刻等處理不穩定，導致半導體的良 率低下。因此，維持固定的半導體處理裝置的藥液的濃度 ，成眾所追求之事。 因此，鑒於習知半導體處理裝置的藥液濃度的補充控 制裝置存在的問題，本發明之目的在於提供一種「半導體 處理裝置之藥液濃度控制裝置」，事先設定補充的液量做 爲基準補充量，再計算相對於基準補充量的各藥液的補充 量，根據計算所得各藥液的補充量來補充藥液，既保持固 定的處理用藥液的濃度，又可維持在處理上必須的液面高 度。 用以解決課顆的手段 本發明之「半導體處理裝置之藥液濃度控制裝置」，* 包括：濃度測定機構，用以測定藥液的濃度；偏移觀測機 構，用以觀測濃度回饋控制系統在經過遲延時間之後的濃 度的變化量；補充量演算機構，用以演算藥液的補充量； 定量補充處理機構，用以處理各藥液之補充量，使該補充 量演算機構所得之各藥液補充量之總和與事前設定好的基 準補充量相等；濃度預測機構，用以預測當補充了該定量 補充處理機構所處理的補充量之後所達到的濃度；以及補 充控制機構，以該定量補充處理機構所處理的補充量對藥 液的補充作控制。 又，本發明「半導體處理裝置之藥液濃度控制裝置」 一 8 - 200423194 的該補充量演算機構，係根據由該濃度測定機構所測定的 濃度數據，及由該偏移觀測機構所觀測的濃度的變化量， 以及由該濃度預測機構所預測的濃度預測數據，演算藥液 的補充量。 又，本發明「半導體處理裝置之藥液濃度控制裝置」 的該定量補充處理機構，係根據藥液的補充優先順序來處 理各藥液的補充量。 又，本發明「半導體處理裝置之藥液濃度控制裝置」 的該補充控制機構，係當藥液的液面位置比既定的位置還 低的時候，進行藥液的補充。 (四）實施方式 以下參照圖面，說明本發明之「半導體處理裝置之藥 液濃度控制裝置」。第1圖係方塊圖，顯示備有藥液濃度 控制裝置的半導體處理裝置的構成，第2圖係方塊圖，顯 示本發明「半導體處理裝置之藥液濃度控制裝置」的控制 部的構成，第3圖係流程圖，顯示「半導體處理裝置之藥 液濃度控制裝置」的濃度控制，第4圖係方塊圖，顯示液 面計使用下「半導體處理裝置之藥液濃度控制裝置」的構 成。 如第1圖所示，半導體處理裝置，包括：處理槽2， 將基板等晶圓浸漬在藥液內以進行洗滌等處理；溢流槽3 ，存積處理槽2溢流出來的藥液；藥液循環路徑4，讓藥 液從溢流槽3循環至處理槽2 ;補充部28的藥液箱9，儲 存補充用的藥液；補充部28的補充泵10， 對溢流槽3補 - 9 - 200423194 充藥液；以及控制部1 5，進行濃度的管理及控制。 藥液循環的藥液循環路徑4上配設有：過濾藥液用的 過濾器5 ;令藥液循環的循環用泵6 ;測定藥液濃度的濃度 測定機構即濃度計7。並且，濃度測定機構的濃度計7之 構成，係當混合使用複數藥液時，可輸出每個藥液的濃度 數據。 本發明「半導體處理裝置之藥液濃度控制裝置」，包 括：測定藥液的濃度的濃度測定機構即濃度計7，以及執 行濃度管理、控制的控制部15。「半導體處理裝置之藥液 濃度控制裝置」，係事先設定補充的液量做爲基準補充量 ，再改變各藥液對基準補充量的混合比，以進行控制。並 且，基準補充量係設定於維持液面高度上的需要量。 測定藥液的濃度的濃度測定機構即濃度計7，如第1 圖所示，連接到從循環用泵6的下游側分岔出來的管線路 徑。濃度計7之構成，可將測得之各藥液的濃度數據輸出 給控制部1 5。 藥液濃度控制裝置的控制部1 5的構成，係依據濃度計 7之濃度數據算出藥液的必須補充量，將算出來的補充量 輸出給補充部28的補充泵1 0。補充部28的補充泵1 〇，則 按既定時機對處理槽2補充由控制部1 5所輸出的補充量。 又，控制部1 5，與管理晶圓製程的上位控制部3 5 (示於第 2圖）即上位電腦相連接，依上位電腦的指令，進行藥液補 充的控制處理。備有第1圖所示之藥液濃度控制裝置的半 導體處理裝置，形成濃度回饋控制系統，做如下控制，依 - 10 - 200423194 據濃度測定機構的濃度計7所測定的濃度數據計算出藥液 的必須補充量’由補充泵1 〇補充所計算出來的補充量以達 到既定之濃度。 其次’用第2圖所示之方塊圖，說明藥液濃度控制裝 置的控制部1 5。 如第2圖所示，藥液濃度控制裝置的控制部1 5，其構 成包括：輸入部20，用以對測定藥液濃度的濃度測定機構 即濃度計7的濃度數據作採樣處理；補充量演算部2 1，即 補充量演算機構，根據輸入部20所採樣的濃度測定機構的 濃度計7的濃度數據，及偏移觀測機構的偏移觀測部26所 觀測的濃度的變化量，及濃度預測機構的濃度預測部24所 預測的濃度預測數據，計算出藥液的補充量；偏移觀測部 26，即偏移觀測機構，利用控制部1 5從動作禁止轉變爲動 作許可時亦即利用不受藥液補充動作影響的區間，測定濃 度回饋控制系統在經過遲延時間後的濃度計7的濃度數據 的變化量；定量補充處理部27，即定量補充處理機構，處 理使得補充量演算部2 1所得之各藥液補充量之總和與基準 補充量相等；補充間隔計時器22，按固定週期計時藥液的 補充的間隔；補充控制部2 3，即補充控制機構，依補充間 隔計時器22的每一個固定週期的信號，按定量補充處理部 27所算出的補充量來控制補充部28 ;濃度預測部24，即 濃度測定機構，用以預測依定量補充處理部27所算之補充 量補充後所達到的濃度；設定輸出入部25，接受上位控制 部3 5的上位電腦的動作許可、禁止的控制信號，設定鍵盤 200423194 、觸摸面板等輸入裝置所輸入的參數，對上位控制部3 5輸 出監視用濃度數據等。 對濃度計7的濃度數據作採樣處理的輸入部20，依固 定週期對濃度計7的濃度數據採樣，爲消除雜訊而進行移 動平均處理或單純平均處理等，並以移動平均處理或單純 平均處理所得之數據做爲濃度數據。 偏移觀測機構的偏移觀測部26，當控制部1 5依上位 控制部3 5的控制信號從動作禁止轉變爲動作許可時，測定 濃度的變化量。亦即，藥液因加熱使用而蒸發，會依一定 的斜率減少藥液的濃度。又，藥液的減少的比例因藥液而 異，故容易蒸發的藥液與不容易蒸發的藥液相混合時，前 者的藥液的濃度減少，而後者的藥液的濃度增加。該變化 量，在不受藥液的補充動作的影響的時機，亦即，控制部 15從動作禁止狀態轉變爲動作許可狀態時時，由偏移觀測 部26觀測之。偏移觀測部26觀測所得之觀測數據，換算 成控制週期的變化量，做爲補充量演算部2 1濃度數據的補 償數據使用。據此，能夠抑制藥液的溫度對濃度變化的影 饗。 偏移觀測部26，當控制部1 5從動作禁止狀態轉變爲 動作許可時讀入輸入部20的濃度數據（PVDn(O))並記憶之 ’其次，經過事先設定的濃度回饋控制系統的遲延時間m2 之後，再讀入輸入部20的濃度數據（PVDn(m))。則，偏移 觀測部26，因觀測開始時機及觀測區間未受補充動作的影 響，故可正確地觀測變化量。其中，η代表藥液的種類。 - 1 2 - 200423194 在經過遲延時間後的濃度的變化量（PVDn)，設控制週 期爲Tent，依下式算出。 PVDn=(PVDn(m)- PVDn(〇 ) )x (Tent / m2)…（1 ) 所算出之各藥液的變化量（pVDn )，從偏移觀測部26輸出至 補充量演算部21。 補充量演算機構的補充量演算部2 1，依據基準補充量 、各藥液的目標濃度、各藥液的濃度數據、藥液的原液濃 度、藥液的混和容積比、藥液的比重等數據，算出各藥液 的補充量。 基準補充量、各藥液的目標濃度、藥液的原液濃度、 藥液的混和容積比、藥液的比重等各數據，係由上位控制 部35輸出至設定輸出入部25，再從設定輸出入部25輸入 於補充量演算部2 1做爲參數。又，各藥液的濃度，係依據 輸入部20過來的濃度計7之濃度數據、偏移觀測部26的 變化量、及濃度預測部24的濃度預測數據捕證而得。 亦即，各藥液的經補正之濃度（PVn)(以下，稱之爲補 正濃度），依下式算出 PVn= PVn ^ + FVn- SVn+ PVDn+ IntDPV...(2) 其中，PVn表示補正濃度，PVn /表示輸入部20採樣的濃度 計7的濃度數據，FVn表示濃度預測部24的濃度預測數據 ，SVn表示目標濃度，PVDn表示偏移觀測部26觀測的變化 量，IntDPV係（PVn / — SVn)的積分値，表示濃度計7之濃 度數據對目標濃度的偏差的積分。 補充量演算部2 1，根據補正濃度（PVn )，由基準補充 _13 - 200423194 量、目標濃度、各藥液的比重、處理槽2內的總液量，算 出各藥液的補充量。補充量演算部2 1算出之各藥液之補充 量的數據送往定量補充處理機構的定量補充處理部27，定 量補充處理部27之處理，係算出各藥液對事先經設定輸出 入部25設定的基準補充量的比率，以維持處理用各藥液的 濃度，讓各藥液補充量之總和等於基準補充量。 例如，假設補充量演算部2 1的演算結果得到藥液A、 B、C各爲基準補充量的50%、40%、30%時，定量補充處理 部27根據由設定輸出入部25設定的藥液的補充優先順序 ，處理各藥液的補充量。例如，假設藥液的補充優先順序 爲藥液A、B、C，則其處理爲藥液A爲50%、藥液B爲40% 、藥液C爲剩餘的1 0%，使各藥液補充量之總和等於基準 補充量。 定量補充處理部27的各藥液之補充量的數據，均送往 補充控制部23及濃度預測部24。補充控制部23則依據補 充間隔計時器22過來的信號，控制補充部28，啓動計時 器補充既定量的藥液。又，補充部2 8亦可不利用計時器控 制，而使用積分流量計，或計算補充泵1 0的s h 〇 t數，以 控制補充量。 濃度測定機構的濃度預測部24，預測在依據定量補充 處理部2 7的各藥液之補充量的數據將補充量補充之後所達 到的濃度，並補正濃度計7的遲延時間。濃度預測部24所 算出的濃度預測數據，用來做爲計算經過遲延時間後的補 充量時的補正數據。亦即，當濃度預測數據（FVn )大於目標 -14- 200423194 濃度（SVn)時，由式（2)，補正濃度（PVn)的値增加，其補正 係減少處理槽2內的藥液的濃度，當濃度預測數據小於目 標濃度（SVn)時，補正濃度（PVn)的値小，其補正係增加處 理槽2內的藥液的濃度。據此，能夠抑制濃度回饋控制系 統的遲延時間所導致的藥液濃度的過度控制。 以下，用第3圖所示之流程圖，說明「半導體處理裝 置之藥液濃度控制裝置」的濃度控制的動作。 如第3圖所示，一開始，由上位控制部3 5過來的基準 補充量、各藥液的目標濃度、藥液的原液濃度、藥液的混 和容積比、藥液的比重等各數據均設定於設定輸出入部2 5 ( 步驟1 )。 其次，輸入部20對濃度計7之濃度數據採樣（步驟S2) 。採樣所得之濃度計7之濃度數據透過設定輸出入部25輸 出給上位控制部35(步驟S3)。 控制部1 5檢查上位控制部3 5是否有輸出動作許可的 信號（步驟S4 )。如動作許可的信號沒有輸出，則反復步驟 S2起的動作。如動作許可的信號有輸出，則檢查是否處於 從動作禁止轉變爲動作許可的狀態（步驟S5 )。如非從動作 禁止轉變爲動作許可的狀態，則移至步驟S 9。如爲從動作 禁止轉變爲動作許可的狀態，則偏移觀測部26讀入輸入部 20的濃度數據（PVDn(O)) ’並記憶所讀入的濃度數據（步驟 S6 )。檢查是否已經過事先設定的濃度回饋控制系統的遲延 時間m2(步驟S7)。如尙未經過遲延時間m2，則移至步驟S9 。如已經過遲延時間m2，則讀入輸入部20的濃度數據 -15 - 200423194 (PVDn(m))，依式（1 )算出變化量（PVDn)，並輸出給補充量 演算部2 1 (步驟S 8 )。Description of the invention (The description of the invention should state: the technical field, the prior art, the content, the embodiments and the drawings of the invention are briefly explained.) (1) The technical field to which the invention belongs. "Device", in a semiconductor processing device, not only maintains a fixed concentration of the processing chemical liquid, but also maintains the level of the liquid chemical liquid necessary for semiconductor processing. (2) Semiconductor processing devices that were previously used in wet cleaning stations, etc., caused the wafer concentration to be changed or the liquid volume to be reduced due to wafer removal from the processing tank and evaporation of the chemical solution. Therefore, the medicinal solution must be replenished regularly to maintain the concentration and volume of the medicinal solution. Fig. 5 shows a block diagram of a conventional "medical solution concentration control device for a semiconductor processing device". As shown in Fig. 5, in order to maintain the concentration of the chemical solution and the height of the liquid surface, the concentration of the chemical solution was measured as a concentration meter. The replenishment control device 40 checks whether the concentration data of the concentration meter 7 is within the reference concentration range, and selects individual replenishment settings when the reference concentration range is within or outside the reference concentration range. ) Output the signal to replenish the liquid medicine. The "medicine liquid concentration control device for semiconductor processing device" shown in Fig. 5 forms a concentration feedback control system, which compares the concentration data measured by the concentration meter 7 with the reference concentration range, and controls the concentration of the chemical liquid to be within the reference concentration range. Inside. The replenishment control of the medicinal solution is shown in Section 6_. The replenishment control device 40 contains a replenishment interval timer that generates a fixed period, and the replenishment of each medicinal solution that is started synchronously with the replenishment interval meter 6-200423194. Timer to replenish a certain amount of medicine. Fig. 6 shows a timing chart of the replenishment control of three kinds of medicines (A medicine liquid, B medicine liquid, and C medicine liquid). As shown in Fig. 6, the signal of the replenishment interval timer of the replenishment control device 40 activates the A medicinal solution replenishment timer, the b medicinal solution replenishment timer, and the C medicinal solution replenishment timer. The timer time of A medicine liquid replenishment timer is τ 1, the timer time of B medicine liquid replenishment timer is T2, the timer time of C medicine liquid replenishment timer is T 3, and the replenishment pumps provided for each medicine liquid Operate within τ 1, T 2, T 3 ^ to replenish a fixed amount of liquid medicine. The time for the replenishment timer of the medicinal solution depends on the concentration. For example, when the concentration of the A solution is higher than the reference concentration range and the concentration of the B solution is lower than the reference concentration range, the setting for the small replenishment of the A solution is selected. Big supplementary settings are added. Similarly, the conventional semiconductor processing device is supplemented with a fixed amount of a chemical solution set in advance in order to maintain the concentration of the chemical solution. (3) Summary of the Invention: The problem to be solved by the invention ❿ However, by comparing the concentration data of the densitometer with the reference concentration range of the target 値, the supplementary control of the medicinal solution by the supplementary control device 40 is known. The influence of mixing time and measurement time of the concentration meter 'as shown in Fig. 7, after t = 0, the concentration data (P) is determined until t = m2 after the chemical solution is replenished, resulting in a delay time m 2 in the concentration feedback control system ( (Illustrated in Figure 8). Therefore, as shown in FIG. 8, when the concentration of the chemical solution is to be controlled within the reference concentration range, due to the influence of the delay time m2 ', it exceeds the upper limit of the reference concentration range, or is lower than the lower limit of the reference concentration range. Got scattered. -Ί-200423194 Similarly, even in the case of PID (proportional-integral-derivative) control, the concentration cannot be controlled with high accuracy due to the influence of the delay time m2. Variation in the concentration of the chemical solution makes processing such as washing and etching unstable, resulting in a low semiconductor yield. Therefore, maintaining the concentration of the chemical solution of the fixed semiconductor processing device has become a matter of public pursuit. Therefore, in view of the problems with conventional supplemental control devices for chemical liquid concentration of semiconductor processing devices, the object of the present invention is to provide a "medical liquid concentration control device for semiconductor processing devices", in which the supplementary liquid amount is set in advance as a reference supplementary amount , Then calculate the replenishment amount of each medicinal solution relative to the reference replenishment amount, and replenish the medicinal solution according to the calculated replenishment amount of each medicinal solution, not only maintaining a fixed concentration of the medicinal solution for processing, but also maintaining the necessary liquid level for processing height. Means for solving the problem The "medicine liquid concentration control device of the semiconductor processing device" of the present invention * includes: a concentration measuring mechanism for measuring the concentration of the chemical liquid; an offset observation mechanism for observing the concentration feedback control system at The amount of change in concentration after the delay time; the replenishment calculation unit is used to calculate the replenishment of the medicinal solution; the quantitative replenishment processing unit is used to process the replenishment of each medicinal solution so that the medicinal solution obtained by the replenishment calculation unit The sum of the replenishment amounts is equal to the baseline replenishment amount set in advance; the concentration prediction mechanism is used to predict the concentration reached when the replenishment amount processed by the quantitative replenishment processing means is replenished; and the replenishment control means is replenished with the quantitative replenishment process The replenishment amount handled by the institution controls the replenishment of the medicinal solution. In addition, the supplementary amount calculation mechanism of "concentration control device for chemical solution of semiconductor processing device" 8-200423194 of the present invention is based on the concentration data measured by the concentration measurement mechanism and the concentration observed by the offset observation mechanism. And the concentration prediction data predicted by the concentration prediction mechanism to calculate the replenishment amount of the medicinal solution. The quantitative replenishment processing mechanism of the "medicine solution concentration control device of the semiconductor processing device" of the present invention processes the replenishment amount of each medicinal solution according to the replenishment priority of the medicinal solution. The replenishment control mechanism of the "medicine solution concentration control device for a semiconductor processing device" of the present invention is to replenish a medicinal solution when the liquid level of the medicinal solution is lower than a predetermined position. (4) Embodiment The "medicine liquid concentration control device for semiconductor processing device" of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram showing a configuration of a semiconductor processing device provided with a chemical liquid concentration control device, and FIG. 2 is a block diagram showing a configuration of a control section of the “medium liquid concentration control device for a semiconductor processing device” according to the present invention. Fig. 3 is a flowchart showing the concentration control of the "concentration control device for the semiconductor processing device", and Fig. 4 is a block diagram showing the structure of the "concentration control device for the semiconductor processing device" under the use of a liquid level meter. As shown in FIG. 1, the semiconductor processing device includes a processing tank 2 for immersing a wafer such as a substrate in a chemical solution for processing such as washing; an overflow tank 3 for storing the chemical solution overflowing from the processing tank 2; The medicine liquid circulation path 4 allows the medicine liquid to circulate from the overflow tank 3 to the treatment tank 2; the medicine liquid tank 9 of the replenishing section 28 stores the medicine liquid for replenishment; the replenishing pump 10 of the replenishing section 28 replenishes the overflow tank 3 -9-200423194 Filling liquid; and control unit 15 to manage and control the concentration. The chemical liquid circulation path 4 of the chemical liquid circulation is provided with: a filter 5 for filtering the chemical liquid; a circulation pump 6 for circulating the chemical liquid; a concentration meter 7 for measuring the concentration of the chemical liquid. In addition, the configuration of the concentration meter 7 of the concentration measuring mechanism is such that when a plurality of chemical solutions are mixed and used, the concentration data of each chemical solution can be output. The "medicine liquid concentration control device for semiconductor processing device" of the present invention includes a concentration meter 7 which is a concentration measuring mechanism that measures the concentration of a chemical liquid, and a control unit 15 that performs concentration management and control. "Semiconductor processing device chemical liquid concentration control device" is to set the amount of liquid to be replenished as the reference replenishment in advance, and then change the mixing ratio of each liquid to the reference replenishment for control. In addition, the reference replenishment amount is set to the amount required to maintain the liquid level. The concentration meter 7, which is a concentration measuring mechanism for measuring the concentration of the chemical solution, is connected to a pipe line branched from the downstream side of the circulation pump 6 as shown in FIG. The structure of the concentration meter 7 can output the measured concentration data of each chemical liquid to the control unit 15. The configuration of the control unit 15 of the chemical liquid concentration control device is to calculate the necessary replenishment amount of the chemical liquid based on the concentration data of the concentration meter 7, and output the calculated replenishment amount to the replenishment pump 10 of the replenishment unit 28. The replenishment pump 10 of the replenishment unit 28 replenishes the replenishment amount output from the control unit 15 to the processing tank 2 at a predetermined timing. The control unit 15 is connected to a higher-level computer 3 (shown in FIG. 2), which manages the wafer manufacturing process, that is, a higher-level computer, and performs a control process for the replenishment of the medicinal solution in accordance with instructions from the higher-level computer. The semiconductor processing device equipped with the chemical liquid concentration control device shown in Fig. 1 forms a concentration feedback control system to perform the following control, and calculates the chemical liquid based on the concentration data measured by the concentration meter 7 of the concentration measuring mechanism. The necessary replenishment amount 'is calculated by the replenishment pump 10 to reach the given concentration. Next, the control unit 15 of the chemical-liquid-concentration control device will be described using the block diagram shown in FIG. As shown in FIG. 2, the control unit 15 of the chemical liquid concentration control device includes an input unit 20 for sampling the concentration data of the concentration meter 7 that is a concentration measuring mechanism for measuring the concentration of the medical liquid; The calculation unit 21, that is, the supplementary quantity calculation mechanism, is based on the concentration data of the densitometer 7 of the concentration measuring mechanism sampled by the input unit 20, and the concentration change amount observed by the offset observation unit 26 of the offset observation mechanism, and the concentration The concentration prediction data predicted by the concentration prediction unit 24 of the prediction mechanism calculates the replenishment amount of the medicinal solution; the offset observation unit 26, that is, the offset observation mechanism, uses the control unit 15 to change from the operation prohibition to the operation permission, that is, to use The interval that is not affected by the replenishment of the medicinal solution measures the change in the concentration data of the concentration meter 7 after the lapse of the concentration feedback control system; the quantitative replenishment processing unit 27, that is, the quantitative replenishment processing unit, processes the replenishment calculation unit 2 The total amount of the replenishment of each medicinal solution obtained in 1 is equal to the reference replenishment amount; the replenishment interval timer 22 measures the replenishment interval of the medicinal solution at a fixed period; the replenishment control unit 23, that is, the replenishment control unit controls the replenishment unit 28 according to the replenishment amount calculated by the quantitative replenishment processing unit 27 according to the signal of each fixed cycle of the replenishment interval timer 22; the concentration prediction unit 24, that is, the concentration measurement mechanism, uses Predict the concentration reached by the supplementary quantity calculated by the quantitative supplementary processing unit 27; set the input / output unit 25, accept the operation permission and prohibition control signals of the host computer of the host control unit 35, and set the keyboard 200423194, touch panel, etc. The parameters input by the input device output the monitoring concentration data and the like to the higher-level control unit 35. The input unit 20 that samples the concentration data of the concentration meter 7 samples the concentration data of the concentration meter 7 at a fixed period, performs moving average processing or simple average processing to eliminate noise, and performs moving average processing or simple average. The processed data were used as concentration data. The offset observation unit 26 of the offset observation mechanism measures the amount of change in concentration when the control unit 15 changes from operation prohibition to operation permission according to a control signal of the upper control unit 35. That is, the medicinal solution evaporates due to heating, and the concentration of the medicinal solution is reduced according to a certain slope. In addition, the reduction ratio of the medicinal solution varies depending on the medicinal solution. Therefore, when the medicinal solution that is easy to evaporate is mixed with the medicinal liquid that is not easy to evaporate, the concentration of the former medicinal solution decreases, and the concentration of the latter medicinal solution increases. This amount of change is observed by the offset observation unit 26 when the control unit 15 changes from the operation-inhibited state to the operation-permitted state when it is not affected by the replenishing operation of the medicinal solution. The observation data obtained by the offset observation section 26 is converted into a change amount of the control period and used as compensation data for the 21 concentration data in the supplement amount calculation section. This makes it possible to suppress the influence of the temperature of the chemical solution on the concentration change. The offset observation unit 26 reads the concentration data (PVDn (O)) of the input unit 20 when the control unit 15 transitions from the operation prohibited state to the operation permission, and then stores the concentration data (PVDn (O)), followed by the delay of the preset concentration feedback control system. After the time m2, the density data (PVDn (m)) of the input unit 20 is read again. Then, the offset observation unit 26 can accurately observe the amount of change because the observation start timing and the observation interval are not affected by the supplementary action. Among them, η represents the type of the medicinal solution. -1 2-200423194 The amount of change in concentration (PVDn) after the lapse of the delay time is set to the control period Tent and calculated according to the following formula. PVDn = (PVDn (m)-PVDn (〇)) x (Tent / m2) ... (1) The amount of change (pVDn) of each chemical solution calculated is output from the offset observation section 26 to the supplementary amount calculation section 21. The replenishment calculation unit 21 of the replenishment calculation mechanism is based on data such as the reference replenishment amount, the target concentration of each medicinal solution, the concentration data of each medicinal solution, the original solution concentration of the medicinal solution, the mixed volume ratio of the medicinal solution, and the specific gravity of the medicinal solution , Calculate the replenishment amount of each medicinal solution. Reference data, target concentration of each medicinal solution, original solution concentration of medicinal solution, mixed volume ratio of medicinal solution, specific gravity of medicinal solution, and other data are output from upper control unit 35 to setting input / output unit 25, and then from setting input / output unit 25 is input to the supplementary amount calculation section 21 as a parameter. The concentration of each chemical solution is obtained based on the concentration data of the concentration meter 7 from the input unit 20, the amount of change in the offset observation unit 26, and the concentration prediction data of the concentration prediction unit 24. That is, the corrected concentration (PVn) of each chemical solution (hereinafter referred to as the corrected concentration), PVn = PVn ^ + FVn-SVn + PVDn + IntDPV ... (2) where PVn represents the corrected concentration , PVn / represents the concentration data of the densitometer 7 sampled by the input unit 20, FVn represents the concentration prediction data of the density prediction unit 24, SVn represents the target concentration, PVDn represents the amount of change observed by the offset observation unit 26, and IntDPV system (PVn /- The integral 値 of SVn) represents the integral of the deviation of the concentration data of the densitometer 7 with the target concentration. The replenishment calculation unit 21 calculates the replenishment amount of each medicinal solution based on the corrected concentration (PVn), supplementing the amount of _13-200423194, the target concentration, the specific gravity of each medicinal solution, and the total amount of liquid in the treatment tank 2. The replenishment amount calculation unit 21 calculates the replenishment data of each medicinal solution and sends it to the quantitative replenishment processing unit 27 of the quantitative replenishment processing mechanism. The quantitative replenishment processing unit 27 calculates each medicinal solution to be set in advance through the setting input / output unit 25. Ratio of the reference replenishment amount to maintain the concentration of each medicinal solution for processing, so that the sum of the replenishment amounts of each medicinal solution is equal to the reference replenishment amount. For example, if the calculation result of the supplementary amount calculation unit 21 obtains 50%, 40%, and 30% of each of the reference supplementary amounts of the medicinal liquids A, B, and C, the quantitative supplementation processing unit 27 uses the medicine set by the setting input / output unit 25. The priority of liquid replenishment is to deal with the replenishment amount of each liquid medicine. For example, suppose that the supplementary order of the medicinal solution is medicinal solution A, B, and C, then the treatment is as follows: medicinal solution A is 50%, medicinal solution B is 40%, and medicinal solution C is the remaining 10%. The sum of the supplements is equal to the baseline supplement. The data of the replenishment amount of each chemical liquid in the quantitative replenishment processing unit 27 is sent to the replenishment control unit 23 and the concentration prediction unit 24. The replenishment control unit 23 controls the replenishment unit 28 based on a signal from the replenishment interval timer 22, and starts a timer to replenish a predetermined amount of chemical liquid. In addition, the replenishment unit 28 may use an integral flow meter instead of the timer control, or calculate the number of sh o t of the replenishment pump 10 to control the replenishment amount. The concentration prediction unit 24 of the concentration measuring mechanism predicts the concentration that will be reached after supplementing the replenishment amount based on the data of the replenishment amount of each chemical solution by the quantitative replenishment processing unit 27, and corrects the delay time of the concentration meter 7. The density prediction data calculated by the density prediction unit 24 is used as correction data when calculating the amount of replenishment after the delay time has elapsed. That is, when the concentration prediction data (FVn) is greater than the target -14-200423194 concentration (SVn), the （of the correction concentration (PVn) increases from the formula (2), and the correction is to reduce the concentration of the chemical solution in the treatment tank 2. When the predicted concentration data is less than the target concentration (SVn), the size of the correction concentration (PVn) is small, and the correction is to increase the concentration of the chemical solution in the processing tank 2. Accordingly, it is possible to suppress excessive control of the chemical liquid concentration due to the delay time of the concentration feedback control system. Hereinafter, the operation of the concentration control of the "medicine liquid concentration control device for a semiconductor processing device" will be described using the flowchart shown in FIG. As shown in FIG. 3, at the beginning, all the data such as the reference replenishment amount from the upper control unit 35, the target concentration of each chemical solution, the original solution concentration of the chemical solution, the mixed volume ratio of the chemical solution, and the specific gravity of the chemical solution Set to the setting input / output section 2 5 (step 1). Next, the input unit 20 samples the concentration data of the density meter 7 (step S2). The density data of the density meter 7 obtained by sampling is output to the higher-level control unit 35 through the setting input / output unit 25 (step S3). The control unit 15 checks whether the upper control unit 35 has a signal for outputting an operation permission (step S4). If the operation permission signal is not output, the operation from step S2 is repeated. If an operation permission signal is output, it is checked whether or not the state is changed from operation prohibition to operation permission (step S5). If the state is not changed from the operation prohibition to the operation permission state, the process proceeds to step S9. When the state is changed from the operation prohibition to the operation permission state, the offset observation unit 26 reads the concentration data (PVDn (O)) 'of the input unit 20 and stores the read concentration data (step S6). It is checked whether the delay time m2 of the density feedback control system set in advance has elapsed (step S7). If the delay time m2 has not elapsed, the process proceeds to step S9. If the delay time m2 has elapsed, read the concentration data of the input unit 20 -15-200423194 (PVDn (m)), calculate the change amount (PVDn) according to formula (1), and output it to the supplementary amount calculation unit 2 1 (step S 8).
其次，補充量演算部2 1，依據步驟1 2濃度預測部24 所算出的濃度預測數據，及偏移觀測部26所算出的變化量 ，依式（2 )算出補正濃度數據（步驟S9 )。依據所算出之補 正濃度數據，補充量演算部21計算各藥液之補充量（步驟 1〇)。定量補充處理部27則處理使得補充量演算部21所得 之各藥液補充量之總和與基準補充量相等（步驟1 1 )。Next, the supplementary amount calculation unit 21 calculates the corrected concentration data according to formula (2) based on the concentration prediction data calculated by the concentration prediction unit 24 in step 12 and the change amount calculated by the offset observation unit 26 (step S9). Based on the calculated correction concentration data, the replenishment amount calculation unit 21 calculates the replenishment amount of each medicinal solution (step 10). The quantitative replenishment processing unit 27 processes the total of the replenishment amounts of the respective medicinal liquids obtained by the replenishment amount calculation unit 21 to be equal to the reference replenishment amount (step 11).
濃度預測部24，依據經過定量補充處理部27處理的 各藥液的補充量的數據，算出當藥液經過補充之後可達到 的濃度預測數據’並將濃度預測數據輸出給補充量演算部 2 1 (步驟1 2 )。補充控制部23檢查補充間隔計時器22是否 爲補充時機（步驟1 3 )，如不爲補充時機，則移至步驟S2， 反復步驟S2起的動作處理。如爲補充時機，則補充控制部 2 3依定量補充處理部2 7處理過的各藥液的補充量來控制 補充部2 8，對處理槽2補充既定量的藥液（步驟1 4 )。 似此，按各藥液的濃度，將基準補充量分配給各藥液 。將基準補充量補充於處理槽2，能夠保持固定的處理槽 的濃度，並且能夠維持固定的處理槽的液量。據此，能夠 維持在處理上必須的液面高度。另外，亦可不用補充間隔 計時器2 2的補充控制，而代之以，使用液面感測器3 〇， 當處理槽2的藥液的液面處於既定液面位置的範圍之外時 即進行補充。 第4圖以方塊圖顯示半導體處理裝置的構成，使用液 一 16- 200423194 面計偵測在處理上必須的液量。如第4圖所示，液面感測 器3 0裝設於溢流槽3的上部，液面感測器30的偵測管30a 位於處理槽2之內。液面感測器3 0之構成，係偵測發生在 偵測管3 0 a內的偵測嘴的液體靜壓力，偵測在處理槽2內 複數液面的位置。液面感測器3 0，如第4圖所示，液面的 偵測位置指定於上限位置、定量位置、補充要求位置、下 限位置等4個處所，當液面感測器30處於上限位置及定量 位置爲“OFF” ，補充要求位置爲“OFF”的狀態時，即由補 充部28補充藥液。又，在溢流槽3監視液面的理由，是因 爲藥液經常循環並溢流至處理槽2故處理槽2的液面爲固 定，但溢流槽3的液面則隨液量而有上有下。 利用液面感測器3 0偵測在處理上必須的液量，並依液 面感測器3 0的信號補充藥液，即能夠控制在處理上必須的 液量於一定範圍內。 本發明的「半導體處理裝置之藥液濃度控制裝置」， 可適用於3種藥液混合的場合及2種藥液混合的場合，又 ，也能夠把水當作藥液加以處理。 如以上所述，本發明的「半導體處理裝置之藥液濃度 控制裝置」，由於把濃度計的遲延時間考慮在內計算補充 量，故可保持固定的藥液的濃度。又，并用液面感測器， 使得維持處理上必須的液量成爲可能。 發明效果 如以上所述，根據本發明「半導體處理裝置之藥液濃 度控制裝置」，既可保持固定的處理用藥液的濃度，又可 -1 7 - 200423194 維持處理上必須的液量，故能夠穩定地進行半導體處理裝 置上的洗滌等處理，且能夠進行均勻的處理。 (五）圖式簡單說明 第1圖係方塊圖，顯示具備藥液濃度控制裝置的半導 體處理裝置的構成。 第2圖係方塊圖，顯示本發明「半導體處理裝置之藥 液濃度控制裝置」的控制部的構成。 第3圖係顯示「半導體處理裝置之藥液濃度控制裝置 」的濃度控制的流程圖。 第4圖係方塊圖，顯示使用液面計的「半導體處理裝 置之藥液濃度控制裝置」的構成。 第5圖顯示進行習知半導體處理裝置之藥液濃度控制 的裝置的方塊圖。 第6圖顯示藉由補充間隔計時器及受其同步啓動的補 充計時器，進行藥液補充的時機。 第7圖顯示濃度控制上濃度數據的變化。 第8圖顯示濃度計之濃度數據的變化。 主^元件符號說明 2 處理槽 3 溢流槽 4 藥液循環路徑 5 過濾器 6 循環用泵 7The concentration prediction unit 24 calculates the concentration prediction data that can be reached after the chemical solution is replenished based on the data of the replenishment amount of each medicinal solution processed by the quantitative replenishment processing unit 27 and outputs the predicted concentration data to the replenishment amount calculation unit 2 1 (Step 1 2). The replenishment control unit 23 checks whether the replenishment interval timer 22 is the replenishment timing (step 13). If it is not the replenishment timing, the replenishment control section 23 moves to step S2 and repeats the operation processing from step S2. If it is the replenishment timing, the replenishment control unit 23 controls the replenishment unit 28 according to the replenishment amount of each chemical liquid processed by the quantitative replenishment processing unit 27, and replenishes the treatment tank 2 with a predetermined amount of the medicinal liquid (step 14). Similarly, the reference replenishment amount is assigned to each medicinal solution according to the concentration of each medicinal solution. By adding the reference replenishment amount to the processing tank 2, the concentration of the fixed processing tank can be maintained, and the liquid amount of the fixed processing tank can be maintained. This makes it possible to maintain the liquid level necessary for processing. In addition, instead of the supplementary control of the supplementary interval timer 22, a liquid level sensor 30 may be used instead. When the liquid level of the chemical liquid in the processing tank 2 is outside the range of the predetermined liquid level position, that is, To supplement. Figure 4 shows a block diagram of the structure of the semiconductor processing device. A 16-200423194 surface meter is used to detect the amount of liquid necessary for processing. As shown in FIG. 4, the liquid level sensor 30 is installed in the upper part of the overflow tank 3, and the detection tube 30a of the liquid level sensor 30 is located inside the processing tank 2. The composition of the liquid level sensor 30 is to detect the static pressure of the liquid in the detection nozzle in the detection tube 30 a, and to detect the positions of the multiple liquid levels in the processing tank 2. The liquid level sensor 30, as shown in Fig. 4, the detection position of the liquid level is specified in four places, such as the upper limit position, the quantitative position, the supplementary required position, and the lower limit position. When the liquid level sensor 30 is in the upper limit position When the quantitative position is "OFF" and the replenishment request position is "OFF", the medicinal solution is replenished by the replenishing section 28. The reason for monitoring the liquid level in the overflow tank 3 is that the liquid level in the processing tank 2 is fixed because the chemical liquid is often circulated and overflows to the processing tank 2. However, the liquid level in the overflow tank 3 varies with the amount of liquid Up and down. The liquid level sensor 30 is used to detect the amount of liquid necessary for processing, and the liquid is replenished according to the signal of the liquid level sensor 30, so that the amount of liquid necessary for processing can be controlled within a certain range. The "medicine liquid concentration control device of the semiconductor processing device" of the present invention can be applied to a case where three kinds of medicinal liquids are mixed and a case where two kinds of medicinal liquids are mixed, and water can also be treated as a medicinal liquid. As described above, the "medical solution concentration control device for a semiconductor processing device" of the present invention can calculate the replenishment amount by taking into account the delay time of the densitometer, so that the concentration of the chemical solution can be maintained constant. In addition, the use of a liquid level sensor makes it possible to maintain a necessary amount of liquid for processing. ADVANTAGEOUS EFFECTS OF THE INVENTION As described above, according to the "medical liquid concentration control device for semiconductor processing device" of the present invention, it is possible to maintain a fixed concentration of the processing liquid and to maintain a necessary amount of liquid for processing. Processing such as washing on a semiconductor processing apparatus is performed stably, and uniform processing is possible. (V) Brief Description of Drawings Fig. 1 is a block diagram showing the structure of a semiconductor processing device including a chemical liquid concentration control device. Fig. 2 is a block diagram showing a configuration of a control section of the "medical liquid concentration control device for a semiconductor processing device" according to the present invention. Fig. 3 is a flowchart showing the concentration control of the "medicine liquid concentration control device for a semiconductor processing device". Fig. 4 is a block diagram showing the configuration of a "medicine liquid concentration control device for a semiconductor processing device" using a liquid level meter. Fig. 5 shows a block diagram of an apparatus for controlling the concentration of a chemical solution in a conventional semiconductor processing apparatus. Fig. 6 shows the timing of replenishment of the liquid medicine by the replenishment interval timer and the replenishment timer activated by the replenishment timer. Figure 7 shows the change in the concentration data in the concentration control. Figure 8 shows the change in the concentration data of the densitometer. Description of main element symbols 2 Processing tank 3 Overflow tank 4 Chemical liquid circulation path 5 Filter 6 Circulation pump 7
濃度計 - 18 - 200423194 9 藥 液 箱 10 補 充 泵 15 控 制 部 20 輸 入 部 21 補 充 量 演 算 部 22 補 充 間 隔 計 時 器 23 補 充 控 制 部 24 濃 度 預 測 部 25 設 定 輸 出 入 部 26 偏 移 觀 測 部 27 定 量 補 充 處 理 部 28 補 充 部 30a 偵 測 管 30 液 面 感 測 器 35 上 位 控 制 部 40 補充控制裝置Density meter-18-200423194 9 Chemical tank 10 Replenishment pump 15 Control section 20 Input section 21 Replenishment amount calculation section 22 Replenishment interval timer 23 Replenishment control section 24 Concentration prediction section 25 Setting input / output section 26 Offset observation section 27 Quantitative replenishment processing Section 28 Supplementary section 30a Detection tube 30 Liquid level sensor 35 Host controller 40 Supplementary control device