201030185 六、發明說明： 【發明所屬之技術領域】 本發明關於銅或銅合金用的蝕刻液、蝕刻方法及蝕刻 液之再生管理方法。 【先前技術】 近年來，電子機器的小型化高機能係急速進展，關於 〇 此等機器中所內藏的印刷電路板，亦強烈要求具有高的線 路密度。 作爲印刷電路板的製造方法，廣泛使用在預先黏著有 銅箔的基板上形成光阻圖型，使用氯化鐵（III)水溶液 等的蝕刻液來去除不要部分的銅箔之減成法。然而，當藉 由此方法來製造印刷電路板時，已知蝕刻液蔓延至光阻圖 型的背面，線寬變成比光阻圖型還細，而且線剖面的形狀 不成爲矩形，即發生所謂的底切（undercut )。若發生底 切，則所形成的線路之電特性變差，而且有無法確保零件 的安裝所必要的面積之問題，故以減成法來製造線路密度 高的印刷電路板係困難。 又，於以氯化鐵（III )水溶液當作主體的銅箔之連 續蝕刻中，隨著蝕刻的進行，氯化鐵（III)變成氯化鐵 (II)，生成氯化銅（Π )當作副生成物，最終地蝕刻液 係劣化到無法使用的狀態爲止，連續運轉係困難。 以使連續運轉成爲可能當作目的，嘗試經時地讀取的 蝕刻液的化學數値，按照其數値的變化，一邊添加各式各 -5- 201030185 樣的再生助劑，一邊進行連續再生運轉的手法。然而’雖 然進行再生可回到能蝕刻的狀態’但是無法回到新液的狀 態。而且，於重複幾次的再生時，最後再生前後的鈾刻液 之組成濃度亦發生大的變化，結果蝕刻速度亦有大的變化 ，一邊確保從新液起的安定蝕刻速度，一邊進行連續再生 運轉係困難。再者，由於溫度或存在於蝕刻液中的泡沫之 影響，無法正確地讀取蝕刻液的化學數値，進行安定的再 生管理亦困難。 例如，作爲用於抑制底切的技術，有提案使用以氯化 鐵（III)當作主成分而加有硫脲的蝕刻液（例如參照專 利文獻1)。又，有提案在以氯化鐵（III)等的氧化性金 屬鹽和無機酸或有機酸當作成分的蝕刻液中，添加苯并三 唑等的唑化合物（例如參照專利文獻2 )。於專利文獻1 及2的技術中，底切的抑制係有某一程度的可能。然而， 於藉由以氯化鐵（III )水溶液當作主體的蝕刻液所進行 的銅箔之連續蝕刻中，隨著蝕刻的進行，氯化鐵（III ) 變成氯化鐵（II )，生成氯化銅（II )當作副生成物，最 後蝕刻液係劣化到無法使用的狀態爲止。因此，於專利文 獻1及2的技術中，安定的連續再生運轉係困難。 亦有提案在蝕刻液的主成分不是氯化鐵（III)，而 是以二價的鹵化銅當作主成分，更加有鹵化鐵的蝕刻液中 ，測定鹵化鐵與鹵化銅的濃度，以其結果爲基礎，添加氧 化劑的方法（例如參照專利文獻3 )。然而，於專利文獻 3的技術中’不僅無法抑制底切，而且於再生過程中，蝕 -6- 201030185 刻速度係大幅變化，亦無法安定的連續再生運轉。 有提案以進行安定的連續再生運轉爲目的，檢測蝕刻 液的氧化還原電位與氯濃度等，相對於1當量的氯酸鹽， 添加特定比例的氯化氫、氯化鐵之方法（例如參照專利文 獻4及5)。然而，於專利文獻4及5的技術中，若進行 再生，則蝕刻液中的組成濃度進行變化，無法確保連續安 定的蝕刻速度。又，關於底切抑制能力，係完全不充分。 φ 作爲蝕刻液的再生裝置，有提案以酸性蝕刻液爲對象 ，將再生氣體的臭氧吹入而使再生，使用流池（flow cell )型的光度計當作測定其劣化程度的手段，而測定蝕刻液 的色、吸光度之蝕刻液再生裝置（例如參照專利文獻6) 。然而，於專利文獻6中，隨著重複地再生，氯化銅濃度 變高，以光度計無法適切的管理，同時蝕刻速度發生變化 ，無法安定連續再生運轉。又，關於底切抑制能力，完全 不充分。再者，隨著溫度的變化，吸光度的値發生變化， φ 或由於存在於蝕刻液中的泡沬之影響，在蝕刻液的色、吸 光度發生大幅振盪，無法進行安定的再生管理。 作爲無電解複合鍍液的自動管理裝置，有提案測定在 至少2個以上的不同波長之透過率或吸光度，由該測定値 藉由運算處理來算出目的之組成濃度的自動分析•管理裝 置（例如參照專利文獻7)。然而，於專利文獻7的技術 中，由使預先配合的鍍液之組成濃度變化的基礎數據來作 成校正曲線，用此算出未知的無電解複合鍍液之濃度，無 法消除溫度的影響或泡沫的影響。 201030185 作爲酸溶液的金屬含量之測定方法，有提案由波長不 囘的複數種之透過度或反射度來算出金屬含量的方法（例 如參照專利文獻8)。於此方法中，的確，如發光強度的 變動、受光元件的感度變動、光學系統的畸變之小變動係 可能修正，但是無法消除溫度的影響或泡沬的影響。 作爲分光測定方法，有提案關於各種輸出的各自變動 原因，在各波長測量相對於每單位的輸出變動原因之輸出 變.動，轉換成投影在部分空間的數據後，求得校正曲線式 ，去除各種誤差變動的分光測定法（例如參照專利文獻9 )。然而，於專利文獻9的技術中，需要所有各種變動原 因的變動數據，而且由於將銅箔處理，當鈾刻液的組成隨 著時間而變化時，預先準備該全部數據係困難，不合實用 先前技術文獻 專利文獻 專利文獻1:美國專利第3144368號說明書 專利文獻2 :美國專利申請案公開第2005/0016961號 說明書（特開2005-330572號公報） 專利文獻3:特開2006-124740號公報 專利文獻4:日本發明專利第3193152號公報 專利文獻5 :日本發明專利第3 320 1 1 1號公報 專利文獻6:特開平8-302487號公報 專利文獻7:美國專利申請案公開第2003/0491 69號 -8 - 201030185 說明書（特開2002-47575號公報） 專利文獻8 :特開2004-294205號公報（無外國家族） 專利文獻9 :美國專利第5227986號說明書（特開平 3-209149號公報） 【發明內容】 發明所欲解決的問題 φ 本發明之課題爲提供底切非常少的蝕刻係可能，而且 即使進行再生，也能從建浴時起保持安定的触刻速度之銅 或銅合金用之鈾刻液及蝕刻方法。又，提供再生前後的蝕 刻速度之變化小，蝕刻液的溫度或存在於蝕刻液中的泡沫 之影響係可能抑制，維護性優異的蝕刻液之再生管理方法 解決問題的手段 φ 本發明者們對於有關問題點進行專心致的硏究，結果 完成以下的發明。即，本發明係一種銅或銅合金用之蝕刻 液，其特徵爲以水當作主成分，含有（1) 5〜20質量％ 的氯化鐵（ΠΙ ) 、（ 2 ) 0.5〜3質量％的氯化銅（π )、 (3 )相對於氯化鐵（III )而言5〜20質量％的與銅形成 不溶性的鹽之化合物所成；一種蝕刻方法，其特徵係將該 蝕刻液當作新液使用；及，一種蝕刻液之再生管理方法， 其特徵爲使用在不同2個以上之波長的透過度之比來進行 再生管理。 -9 - 201030185 於蝕刻方法中，與銅形成不溶性的鹽之化合物較佳爲 草酸。 於蝕刻液的再生管理方法中，較佳爲在同一光路內同 時計測求得2個以上之波長的透過度之比，進行触刻液的 再生管理。 發明的效果 本發明的第一特徵係蝕刻液。本發明的蝕刻液由於氯 @ 化鐵（III)及氯化銅（Π)濃度在規定的範圍內，含有與 銅形成不溶性的鹽之化合物，故以往困難的底切非常少的 蝕刻係成爲可能，藉由具有高線路密度的印刷電路板之減 成法來製造係成爲可能。又，作爲形成銅與不溶性的鹽之 化合物，尤其藉由使用草酸，可更抑制底切，同時在蝕刻 液的使用中不發生有毒氣體，而且由於僅由處理方法確立 的成分所構成，故使用後的處理亦容易且可完全地行，也 容易回避勞動衛生上、公害防止上及環境保全上的問題。 n 本發明的第二特徵係藉由蝕刻液而導致安定的連續再 生運轉。本發明的蝕刻液由於係一種飩刻液的配合，其預 先考慮銅箔的蝕刻量及與其相當的再生和溢流所伴隨的氯 化銅、其它添加物之濃度變化，即使照原樣地建浴，開始 再生，也幾乎看不到蝕刻液中的各種組成濃度之變化，可 經常地保持新液的組成濃度，可自建浴時起保持安定的蝕 刻速度。 本發明的第三特徵係藉由再生管理而導致安定的連續 -10- 201030185 再生操作。本發明的再生管理係測定蝕刻液的透過度，與 一般所用的氧化還原電位（以下簡稱「ORP」）相比，由 於對於銅的溶解量變化係非常敏感地反應，故細小循環的 再生管理係成爲可能。因此，蝕刻液中再生前後的各種組 成濃度之變化亦非常少，再生前後可保持安定的蝕刻速度 〇 本發明的第四特徵係藉由管理透過度比，而可抑制蝕 Φ 刻液的溫度變化之影響與存在於蝕刻液中的泡沬之影響。 於測定以氯化鐵（III)與氯化銅（II )當作成分的蝕刻液 之透過度時，隨著蝕刻液的溫度上升，透過度降低。雖然 也有預先計測蝕刻液的溫度與透過度之關係，進行修正之 方法，但是由於蝕刻液的組成係隨著銅的溶解而隨時變化 ，進行正確的修正係困難。又，當蝕刻液中有細小的氣泡 存在時，同樣地透過度亦降低。一般地，於蝕刻中使用由 噴淋嘴噴射蝕刻液的方式，其返回液含有許多細的氣泡， Φ 當使用含有此氣泡的蝕刻液時，透過度係大幅振盪，作爲 管理指標係變困難。亦有使蝕刻液循環至另一槽，以減輕 氣泡的影響之方法，但若加長循環，則無法即時地計測， 用於再生的藥液之添加有延遲之虞。再者，尤其進行藉由 過氧化氫的再生時等，由於泡沬係隨著再生反應而發生， 怎麼也無法去掉氣泡。當以光學的方法進行蝕刻液的再生 管理時，此等現象係成爲致命，但是計算在隨著銅的溶解 而特徵變化的波長、隨著溫度的變化或氣泡的混入而特徵 變化的波長之至少2個以上的波長所測定的透過度之比， -11 - 201030185 用作爲再生管理的指標，則可顯著抑制溫度變化的影響、 氣泡混入的影響。 本發明的第五特徵係藉由在同一光路內同時計測在不 同2個以上的波長之透過度的比，而可進一步抑制存在於 蝕刻液中的泡沫之影響。蝕刻液中的組成濃度或尤其泡沬 的含量與其形狀，由於係隨著測定場所、時間而隨時變化 ，故爲了正確地掌握瞬間的蝕刻液之狀態，在同一光路內 同時測定不同波長的透過度係有效，藉由進行此操作，可 更抑制蝕刻液中的泡沬之影響。 本發明的第六特徵係維護性優異之點。以往之藉由 ORP或離子濃度、pH等來管理蝕刻液時，將各種感測器 浸漬在蝕刻液中而進行計測，但是若長時間浸漬在酸性強 的蝕刻液中，則由於氧化物的附著或感測器本身的劣化， 無法測定正確的値，必須定期地進行維護作業。對於此， 當測定透過度時，由於例如可使飩刻液在流池等中循環， 不使直接接觸蝕刻液而由外部測定通過流池的蝕刻液，故 完全不需要定期的維護，可長期間免維護而照原樣地連續 測定。 根據上述，藉由使用本發明的蝕刻液，才可極度抑制 底切，而且可藉由蝕刻速度變化極少的減成法來安定地連 續製造。又，藉由使用本發明的再生管理方法，再生前後 的蝕刻速度之變化小，可抑制蝕刻液的溫度或存在於蝕刻 液中的泡沫之影響，不需要維護的蝕刻液之再生管理係成 爲可能。 -12- 201030185 【實施方式】 實施發明的形態 本發明的蝕刻液含有氯化鐵（III)當作第一必要成 分。本發明的蝕刻液中氯化鐵（III )的濃度，相對於蝕 刻液的總量而言，必須爲5〜20質量％，更佳爲5〜10質 量％。此係因爲氯化鐵（III )的濃度若比5質量％低， φ 則蝕刻速度顯著變慢而不合實用，而氯化鐵（ΙΠ )的濃 度若比20質量％高，則底切的抑制變不充分。 調製本發明的蝕刻液時所用的氯化鐵（III )之形態 係沒有特別的限定，可溶解無水物或六水合物的固體而使 用，也可將市售的氯化鐵（III)適宜稀釋而當作水溶液 使用。再者，固態的氯化鐵（III )通常當作六水合物（ 式量270.3 )來供給，但是本發明中的氯化鐵（III )濃度 之計算係以無水物（式量1 6 2.2 1 )爲基準來進行。例如， φ 於調製含有10質量％的氯化鐵（III)之本發明的蝕刻液 1.0公斤時，氯化鐵（III)六水合物係變成使用其的1公 斤 xio 質量 ％χ ( 270.3/162.21) =167 克。 本發明的蝕刻液含有氯化銅（II )當作第二必要成分 。本發明的蝕刻液中氯化銅（II )的濃度，相對於蝕刻液 的總量而言，必須爲0.5〜3質量％，較佳爲0.5〜2質量 %。此係因爲當氯化銅的濃度比0.5質量％還低時，在進 行再生過程中，隨著氯化銅濃度變化，蝕刻速度的變化變 大’難以確保安定的蝕刻時間，當氯化銅（II )的濃度比 -13- 201030185 3質量％高時，底切的抑制有變不充分之虞。 調製本發明的蝕刻液時所用的氯化銅（II )之形態係 沒有特別的限定，可溶解無水物或水合物的固體而使用， 也可將市售的氯化銅（II)適宜稀釋而當作水溶液使用。 再者，固態的氯化銅（II)通常當作二水合物（式量 17 0.48 )來供給，但是本發明中的氯化銅（II )濃度之計 算係以無水物（式量1 34.45 )爲基準來進行。例如，於調 製含有2質量％的氯化銅（II)之本發明的蝕刻液1公斤 q 時，氯化銅（II)二水合物係變成使用其的1公斤χ2質量 % X ( 1 70.48/1 34.45 ) =25.36 克 ° 本發明的蝕刻液含有形成銅與不溶性的鹽之化合物當 作第三必要成分。與銅形成不溶性的鹽之化合物係沒有特 別的限制，具體地可以使用草酸或含有1個以上的氮之雜 5員環化合物的唑等。作爲唑，可以使用咪唑系化合物、 三唑化合物、四唑化合物等。其中，更佳爲使用草酸。用 草酸的本發明之蝕刻液，係可更抑制底切，不發生如硫化 ^ 氫的有毒氣體，而且由於僅由處理方法確立的成分所構成 ，故使用後的處理亦容易且可完全地行，也容易回避勞動 衛生上、公害防止上及環境保全上的問題。添加量相對於 氯化鐵（III)而言爲5〜20質量％，較佳爲5〜15質量 %。此係因爲當添加量比5質量％少時，底切的抑制變不 充分，而當添加量比20質量％多時，發生蝕刻需要非常 長的時間，或不能充分蝕刻微細間隔的問題。 於調製本發明的蝕刻液時，所用的草酸之形態係沒有 -14 - 201030185 特別的限定，可溶解無水物或二水合物的固體而使用，也 可將市售的草酸適宜稀釋而當作水溶液使用。再者，固態 的草酸通常當作二水合物（式量126.07)來供給，但是本 發明中的草酸濃度之計算係以無水物（式量90.04)爲基 準來進行。例如，於調製含有1質量％的草酸之本發明的 蝕刻液1公斤時，草酸二水合物係變成使用其的1公斤xl 質量 ％ X ( 126.07/90.04) =14 克。 φ 使用本發明的蝕刻液來進行蝕刻時，蝕刻液的溫度較 佳爲15〜45°C，更佳爲25〜35°C。此係因爲當該溫度比 此還低時，蝕刻速度會顯著降低，而當該溫度比此還高時 ，底切的抑制有變不充分之虞。 於本發明的蝕刻液中，亦可含有界面活性劑、消泡劑 、醇、二醇等的潤濕促進劑等，但不是必要。 本發明的蝕刻液係可當作新液使用的蝕刻液。若使用 本發明的蝕刻液當作新液，則於再生時，可以使成爲本發 Φ 明的蝕刻液之組成濃度的方式進行再生。 於本發明中，蝕刻液之再生時所用的氧化劑係沒有特 別的限定，可使用一般所用的氧化劑。例如，可使用氯氣 、臭氧、過氧化氫、氯酸鹽類等，但從環境及安全性的觀 點來看，較隹爲使用氯酸鹽類，更佳爲氯酸鈉、氯酸鉀。 於本發明中，蝕刻液的再生管理手法係可使用一般所 用的管理方法。例如，可測定各種離子濃度、ORP、pH、 比重、透過度等來進行管理。從減少再生前後的蝕刻速度 之變化的觀點來看，宜以細小的循環重複再生反應，較佳 -15- 201030185 爲主要使用檢測感度高的透過度。 於測定蝕刻液的透過度之再生管理方法中，測定透過 度的機器係沒有特別的限制，可使用光電光度計、分光光 度計、色彩感測器、纖維感測器等一般所用者。作爲測定 方法，例如宜爲使蝕刻液在流池等中經常循環，不使直接 接觸蝕刻液，而由外部進行測定的方法。如此地，藉由將 在線上（on-line)所測定的數値與預先決定的管理劣化程 度的設定値作對比’可添加必要量的用於再生之氧化劑等 〇 測定的波長係在含有氯化鐵（III)與氯化銅（II)的 蝕刻液之透過度峰所存在的400〜75 Onm之範圍內進行。 依照本發明的方法’當使用在不同2個以上的波長之透過 度的比時，使用存在於400〜750nm的波長範圍內之透過 度峰的極大點之前後的波長。藉由測定比極大點還大的波 長，可測定銅的溶解所致的鈾刻液之劣化程度，藉由測定 比極大點還小的波長’計測其比，可抑制溫度或泡沫的影 響。例如，當極大點存在於550nm時，可使用500nm與 600nm等。測定透過度的波長之選擇，係可藉由蝕刻液的 配合來隨時設定。較佳爲只必要選擇複數最合適的波長來 使用。 於測定透過度時’較佳爲在同一光路內同時計測。本 發明中的同時計測’係指〇〜1 00msec以內測定在二個以 上的波長之透過度。作爲同時計測的方法，例如可用使白 色光發光’僅選擇受光部所必要的波長範圍之透過度來計 -16- 201030185 測的方法，在上述測定範圍內依順序切換必要的波長，使 發光而計測的方法等。 於本發明的再生管理方法中，所添加的再生液係新液 與氧化劑。新液係藉由對應於鈾刻所進行的劣化液與劣化 程度以一定的比例進行置換，而可去除蝕刻處理過程或再 生反應所產生的各種氧化物或副生成物。新液係含有氯化 鐵（III )與再生反應所必要的鹽酸之蝕刻液，按照需要 Φ 可添加形成銅與不溶性的鹽之化合物或界面活性劑、消泡 劑'醇、二醇等的潤濕促進劑等當作其它成分。 於本發明中，蝕刻液的再生時所用的氧化劑係沒有特 別的限定，可以使用一般所用的氧化劑。例如可以使用氯 氣、臭氧、過氧化氫、氯酸鹽類等，但是從環境及安全性 的觀點來看，較佳爲使用氯酸鹽類，更佳爲氯酸鈉、氯酸 鉀。 於本發明中，印刷電路板之製造時所使用貼銅箔基材 # 之種類係沒有特別的限定。作爲基材，可使用在紙苯酚樹 脂、紙環氧樹脂、塑膠環氧樹脂等的纖維基材中含浸有熱 硬化樹脂者，或用聚酯、聚醯亞胺、聚四氟乙烯等的氟化 樹脂等之各種熱塑性樹脂的板材者，或其它各種絕緣性的 板狀或薄膜狀的材料，而且作爲銅箔，可使用由軋製銅、 電解銅等所成的銅箔，或由各種銅合金所成的箔。基材與 銅箔的貼合方法亦沒有特別的限制，可使用環氧系等的黏 著劑來黏著基材與銅箔，也可在使基材所用的樹脂硬化之 前貼合銅箔，然後使樹脂硬化而黏著，而且亦可使用於銅 •17- 201030185 箔上展開基材所用的樹脂之溶液或熱熔融物後，去除溶劑 或進行冷卻固化等的方法。 於本發明中，印刷電路板之製造時所使用的光阻係沒 有特別的限制，可使用鹼來顯像去除以光照射成爲可溶化 的部分而形成圖型之所謂的正型光阻，或顯像去除以光照 射成爲未硬化部分的圖型之所謂的負型光阻，以及藉由網 版印刷法或其它印刷法來形成的圖型的各種光阻。 本發明的蝕刻液係適合使用於銅或銅合金的蝕刻。本 發明中的銅合金係指含有50質量％以上的銅之合金，作 爲其例，銅與錫的合金（青銅）、銅與錫和磷的合金（磷 青銅）、銅與鎳和鋅的合金（鋅白銅）、銅與鋅的合金（ 黃銅）、銅與鎳的合金（白銅）係代表者。 再者，使用本發明的蝕刻液後，或將溢流液廢棄時， 藉由最基本的重金屬之處理步驟的1種，即添加氫氧化鈣 以將pH調整至弱鹼的步驟，由於所含有的有害化學物種 之鐵（II)離子、鐵（ΠΙ)離子、銅（D離子、銅（η) 離子及草酸離子的全部被完全地沈降去除，故在使用後的 處理也可容易且完全地進行’亦容易回避勞動衛生上、公 害防止上及環境保全上的問題。 實施例 (實施例1 ) [蝕刻液的調製] 於270克（無水物爲1〇〇克）市售的40。波美（ 201030185201030185 VI. Description of the Invention: [Technical Field] The present invention relates to an etching solution for copper or a copper alloy, an etching method, and a regeneration management method for an etching solution. [Prior Art] In recent years, the miniaturization and high-performance of electronic equipment has progressed rapidly, and it is strongly demanded that a printed circuit board built in such machines has a high line density. As a method for producing a printed wiring board, a resist pattern in which a resist pattern is formed on a substrate to which a copper foil is adhered in advance, and an etching solution such as an aqueous solution of iron (III) chloride is used to remove a copper foil of an unnecessary portion. However, when a printed circuit board is manufactured by this method, it is known that the etching liquid spreads to the back surface of the photoresist pattern, the line width becomes thinner than the resist pattern, and the shape of the line cross section does not become a rectangle, that is, the so-called Undercut. If the undercut occurs, the electrical characteristics of the formed wiring are deteriorated, and there is a problem that the area necessary for mounting the component cannot be ensured. Therefore, it is difficult to manufacture a printed circuit board having a high line density by the subtractive method. Further, in the continuous etching of a copper foil mainly composed of an aqueous solution of iron (III) chloride, as the etching proceeds, iron (III) chloride becomes iron (II) chloride, and copper chloride (Π) is formed. As a by-product, the etching liquid is finally deteriorated to an unusable state, and continuous operation is difficult. For the purpose of continuous operation, it is possible to try to continuously regenerate the chemical enthalpy of the etching solution that has been read over time, and add various regenerating aids of the type -5 to 201030185 in accordance with the change in the number of enthalpy. The way of operation. However, 'although the reproduction can be returned to the etchable state', it is impossible to return to the state of the new liquid. Further, when the regeneration is repeated several times, the composition concentration of the uranium engraving liquid before and after the final regeneration also greatly changes, and as a result, the etching rate is greatly changed, and the continuous etching operation is performed while ensuring the stable etching rate from the new liquid. It is difficult. Further, due to the influence of temperature or foam existing in the etching liquid, it is difficult to accurately read the chemical number of the etching liquid, and it is difficult to carry out stable regeneration management. For example, as a technique for suppressing undercut, it is proposed to use an etching solution containing iron (III) as a main component and thiourea (for example, refer to Patent Document 1). In addition, an azole compound such as benzotriazole is added to an etching solution containing an oxidizing metal salt such as iron (III) chloride or an inorganic acid or an organic acid as a component (for example, see Patent Document 2). In the techniques of Patent Documents 1 and 2, the suppression of undercutting has a certain degree of possibility. However, in the continuous etching of the copper foil by the etching solution using the aqueous solution of iron (III) chloride as the main body, iron(III) chloride becomes iron (II) chloride as the etching progresses. Copper (II) chloride is used as a by-product, and finally the etching liquid is deteriorated to an unusable state. Therefore, in the techniques of Patent Documents 1 and 2, stable continuous regeneration operation is difficult. It is also proposed that the main component of the etching solution is not iron (III) chloride, but the divalent copper halide is used as a main component, and the concentration of the iron halide and the copper halide is measured in an etching solution containing iron halide. Based on the result, a method of adding an oxidizing agent (for example, refer to Patent Document 3). However, in the technique of Patent Document 3, not only the undercutting cannot be suppressed, but also during the regeneration process, the ecclesia -6-201030185 has a large change in speed, and it is also impossible to stabilize the continuous regeneration operation. In order to perform a stable continuous regeneration operation, a method of adding a specific ratio of hydrogen chloride or ferric chloride to one equivalent of chlorate is described for the purpose of detecting an oxidation-reduction potential and a chlorine concentration of an etching solution (for example, refer to Patent Document 4). And 5). However, in the techniques of Patent Documents 4 and 5, when the regeneration is performed, the composition concentration in the etching liquid changes, and the continuous etching rate cannot be ensured. Moreover, the undercutting inhibition ability is completely insufficient. φ is an apparatus for regenerating an etchant. It is proposed to use an acid etchant to blow ozone into the regeneration gas for regeneration. A flow cell type photometer is used as a means for measuring the degree of deterioration. An etching liquid regenerating device for color and absorbance of an etching liquid (see, for example, Patent Document 6). However, in Patent Document 6, as the regeneration is repeated, the concentration of copper chloride is increased, the photometer is not properly managed, and the etching rate is changed, so that the continuous regeneration operation cannot be stabilized. Moreover, the undercutting ability is not sufficient at all. Further, as the temperature changes, the enthalpy of the absorbance changes, and φ or the influence of the bubble existing in the etching liquid greatly oscillates the color and absorbance of the etching liquid, and stable regeneration management cannot be performed. As an automatic management device for an electroless composite plating solution, there is a proposal for an automatic analysis and management device for measuring the transmittance of at least two or more different wavelengths, and calculating the composition concentration of the target by calculation. Refer to Patent Document 7). However, in the technique of Patent Document 7, a calibration curve is created by using basic data in which the composition concentration of the plating solution to be previously mixed is changed, and the concentration of the unknown electroless composite plating solution is calculated by this, and the influence of temperature or the foam cannot be eliminated. influences. 201030185 As a method of measuring the metal content of the acid solution, there is a proposal to calculate the metal content from a plurality of kinds of transmittances or reflectances of wavelengths (see, for example, Patent Document 8). In this method, it is confirmed that the fluctuation of the luminous intensity, the variation of the sensitivity of the light receiving element, and the small variation of the distortion of the optical system may be corrected, but the influence of temperature or the influence of the bubble cannot be eliminated. As a spectrometry method, there are proposals for the respective fluctuation causes of various outputs, and the output changes with respect to the output variation per unit are measured at each wavelength, and converted into data projected in a partial space, and then a calibration curve is obtained and removed. Spectrometry for various error variations (see, for example, Patent Document 9). However, in the technique of Patent Document 9, all kinds of fluctuation data of various causes of variation are required, and since the composition of the uranium engraving changes with time when the copper foil is processed, it is difficult to prepare the entire data in advance, which is not practical. CITATION LIST Patent Literature Patent Literature 1: U.S. Patent No. 3,144,368, the disclosure of which is incorporated herein by reference. Japanese Unexamined Patent Publication No. Hei. No. Hei. No. Hei. No. Hei. No. Hei. No. Hei. No. Hei. No. Hei. 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 SUMMARY OF THE INVENTION Problems to be Solved by the Invention φ An object of the present invention is to provide an etching system having very few undercuts, and even if regeneration is performed, Maintaining stability when starting from a bath of touch speed engraved copper or copper alloy with the uranium solution and etching method moment. Further, the change in the etching rate before and after the regeneration is small, and the influence of the temperature of the etching liquid or the foam existing in the etching liquid may be suppressed, and the method for regenerating the etching liquid excellent in maintainability is a means for solving the problem. Investigate the problem points and focus on the following inventions. That is, the present invention is an etching solution for copper or copper alloy characterized by containing (1) 5 to 20% by mass of ferric chloride (ΠΙ), (2) 0.5 to 3 mass%, with water as a main component. a copper chloride (π), (3) compound having 5 to 20% by mass of a copper-insoluble salt with respect to iron (III) chloride; an etching method characterized by using the etching solution And a method for regenerating an etching liquid, characterized in that regeneration management is performed using a ratio of transmittances at different wavelengths of two or more. -9 - 201030185 In the etching method, the compound which forms an insoluble salt with copper is preferably oxalic acid. In the method for regenerating the etching liquid, it is preferable to simultaneously calculate the ratio of the transmittances of two or more wavelengths in the same optical path, and perform the regeneration management of the etchant. EFFECT OF THE INVENTION The first feature of the present invention is an etching liquid. In the etching liquid of the present invention, since the concentration of chlorine@iron (III) and copper chloride (Π) is within a predetermined range and contains a compound which forms an insoluble salt with copper, it is possible to have an etching system having a very small undercut in the past. It is possible to manufacture a system by a subtractive method of a printed circuit board having a high line density. Further, as a compound which forms copper and an insoluble salt, in particular, by using oxalic acid, undercut can be further suppressed, and toxic gas does not occur during use of the etching liquid, and since it is composed only of components established by the treatment method, it is used. The post-processing is also easy and completely feasible, and it is easy to avoid problems in labor hygiene, pollution prevention, and environmental preservation. n The second feature of the present invention results in a stable continuous regeneration operation by an etchant. In the etching liquid of the present invention, the etching amount of the copper foil is preliminarily considered, and the concentration of the copper foil and the concentration of the copper chloride and other additives accompanying the regeneration and overflow corresponding thereto are considered in advance, and the bath is built as it is. At the beginning of regeneration, almost no change in the composition concentration in the etching liquid is observed, and the composition concentration of the new liquid can be constantly maintained, and the stable etching rate can be maintained from the time of self-building of the bath. The third feature of the present invention results in a stable continuous -10- 201030185 regeneration operation by regeneration management. The regeneration management system of the present invention measures the transmittance of the etching liquid, and is more sensitive to the change in the amount of dissolved copper than the oxidation-reduction potential (hereinafter referred to as "ORP") generally used. become possible. Therefore, the variation of various composition concentrations before and after regeneration in the etching solution is very small, and the stable etching rate can be maintained before and after the regeneration. The fourth feature of the present invention can suppress the temperature change of the etching solution by managing the transmittance ratio. The effect is affected by the bubbles present in the etchant. When the transmittance of the etching liquid containing iron (III) chloride and copper (II) chloride as a component is measured, the transmittance is lowered as the temperature of the etching liquid rises. Although the method of correcting the relationship between the temperature and the transmittance of the etching liquid is measured in advance, the composition of the etching liquid changes with time due to the dissolution of copper, and it is difficult to perform correct correction. Further, when fine bubbles are present in the etching liquid, the transmittance is also lowered. In general, in the etching, an etchant is sprayed from a shower nozzle, and the return liquid contains a large number of fine bubbles. Φ When an etchant containing the bubbles is used, the transmittance greatly oscillates, which becomes difficult as a management index. There is also a method of circulating the etching liquid to another tank to reduce the influence of the air bubbles. However, if the circulation is lengthened, the measurement cannot be performed instantaneously, and the addition of the chemical liquid for regeneration may be delayed. Further, in particular, when regeneration by hydrogen peroxide is performed, the bubble system is generated by the regeneration reaction, and the bubble cannot be removed. When the etchant is regenerated and managed optically, these phenomena are fatal, but at least the wavelengths that change in characteristics as the copper dissolves, the wavelengths that change with the change of temperature or the incorporation of bubbles, are calculated. The ratio of the transmittance measured by two or more wavelengths, -11 - 201030185, is used as an indicator of regeneration management, and the influence of temperature change and the influence of bubble mixing can be remarkably suppressed. According to a fifth aspect of the present invention, the influence of the bubbles present in the etching liquid can be further suppressed by simultaneously measuring the ratio of the transmittances at different wavelengths in the same optical path. The composition concentration in the etching solution, in particular, the content and shape of the foam, varies with the measurement site and time. Therefore, in order to accurately grasp the state of the instantaneous etching liquid, the transmittance of different wavelengths is simultaneously measured in the same optical path. It is effective, and by doing this, the influence of the bubble in the etching liquid can be further suppressed. The sixth feature of the present invention is excellent in maintainability. Conventionally, when the etching liquid is managed by ORP, ion concentration, pH, or the like, various sensors are immersed in an etching liquid to measure. However, if it is immersed in an acidic etching liquid for a long period of time, adhesion of oxide is caused. Or the deterioration of the sensor itself, the correct flaw cannot be measured, and maintenance work must be performed periodically. In this case, when the transmittance is measured, for example, the etching liquid can be circulated in the flow cell or the like, and the etching liquid passing through the flow cell can be externally measured without directly contacting the etching liquid, so that regular maintenance is not required at all, and the length can be long. It is continuously measured as it is without maintenance during the period. According to the above, by using the etching liquid of the present invention, undercutting can be extremely suppressed, and it can be stably and continuously manufactured by a subtractive method in which the etching rate is extremely changed. Further, by using the regeneration management method of the present invention, the change in the etching rate before and after the regeneration is small, and the influence of the temperature of the etching liquid or the foam existing in the etching liquid can be suppressed, and the regeneration management system of the etching liquid which does not require maintenance becomes possible. . -12-201030185 [Embodiment] Embodiment of the Invention The etching liquid of the present invention contains iron (III) chloride as a first essential component. The concentration of iron (III) chloride in the etching solution of the present invention must be 5 to 20% by mass, more preferably 5 to 10% by mass based on the total amount of the etching solution. In this case, since the concentration of iron (III) chloride is lower than 5% by mass, the etching rate is remarkably slow and practical, and if the concentration of ferric chloride (ΙΠ) is higher than 20% by mass, the undercut is suppressed. Not fully changed. The form of the iron (III) chloride used in the preparation of the etching liquid of the present invention is not particularly limited, and it can be used by dissolving an anhydrate or a solid of hexahydrate, and the commercially available iron (III) chloride can be appropriately diluted. It is used as an aqueous solution. Further, the solid iron(III) chloride is usually supplied as a hexahydrate (formula amount 270.3), but the iron (III) chloride concentration in the present invention is calculated as an anhydrate (formation amount 1 6 2.2 1) ) is based on the benchmark. For example, when φ is used to prepare 1.0 kg of the etching solution of the present invention containing 10% by mass of iron(III) chloride, the iron(III) chloride hexahydrate system becomes 1 kg xio mass% 使用 (270.3/162.21) using the same. ) =167 grams. The etching solution of the present invention contains copper (II) chloride as a second essential component. The concentration of copper (II) chloride in the etching solution of the present invention must be 0.5 to 3% by mass, preferably 0.5 to 2% by mass based on the total amount of the etching solution. This is because when the concentration of copper chloride is lower than 0.5% by mass, during the regeneration process, as the concentration of copper chloride changes, the change in etching rate becomes large. It is difficult to ensure a stable etching time when copper chloride ( When the concentration of II) is higher than -13 to 30,030,185, the mass of the undercut is insufficient. The form of the copper (II) chloride used in the preparation of the etching liquid of the present invention is not particularly limited, and it can be used by dissolving a solid of an anhydrate or a hydrate, and the commercially available copper (II) chloride can be appropriately diluted. Used as an aqueous solution. Further, the solid copper (II) chloride is usually supplied as a dihydrate (formula amount: 17.4), but the copper (II) chloride concentration in the present invention is calculated as an anhydrate (formula 1 34.45). Conducted as a benchmark. For example, when 1 kg of the etching liquid of the present invention containing 2% by mass of copper (II) chloride is prepared, the copper (II) chloride dihydrate becomes 1 kg of χ 2% by mass of X (1 70.48 / 1 34.45 ) = 25.36 g The etching solution of the present invention contains a compound which forms copper and an insoluble salt as a third essential component. The compound which forms an insoluble salt with copper is not particularly limited, and specifically, oxalic acid or azole containing one or more nitrogen-containing heterocyclic compounds may be used. As the azole, an imidazole compound, a triazole compound, a tetrazole compound or the like can be used. Among them, it is more preferable to use oxalic acid. The etching solution of the present invention using oxalic acid can suppress the undercut more, does not generate a toxic gas such as hydrogen sulfide, and is composed of components which are only established by the treatment method, so that the treatment after use is also easy and completely possible. It is also easy to avoid problems in labor hygiene, pollution prevention and environmental preservation. The amount of addition is 5 to 20% by mass, preferably 5 to 15% by mass based on the iron (III) chloride. This is because when the amount added is less than 5% by mass, the suppression of the undercut becomes insufficient, and when the amount added is more than 20% by mass, the etching takes a very long time or the problem of the fine interval cannot be sufficiently etched. When preparing the etching solution of the present invention, the form of oxalic acid used is not particularly limited by -14 to 201030185, and can be used by dissolving an anhydrate or a solid of dihydrate, and the commercially available oxalic acid can be appropriately diluted as an aqueous solution. use. Further, solid oxalic acid is usually supplied as a dihydrate (formula amount: 126.07), but the calculation of the oxalic acid concentration in the present invention is carried out based on an anhydride (formula amount: 90.04). For example, when 1 kg of the etching liquid of the present invention containing 1% by mass of oxalic acid is prepared, the oxalic acid dihydrate becomes 1 kg x 1 mass % X (126.07/90.04) = 14 g using the same. φ When etching is performed using the etching liquid of the present invention, the temperature of the etching liquid is preferably 15 to 45 ° C, more preferably 25 to 35 ° C. This is because when the temperature is lower than this, the etching speed is remarkably lowered, and when the temperature is higher than this, the suppression of the undercut becomes insufficient. The etching solution of the present invention may contain a surfactant, an antifoaming agent, a wetting accelerator such as an alcohol or a glycol, and the like, but it is not essential. The etching liquid of the present invention can be used as an etching liquid for a new liquid. When the etching liquid of the present invention is used as a new liquid, it is possible to regenerate the composition of the etching liquid of the present invention at the time of regeneration. In the present invention, the oxidizing agent used in the regeneration of the etching liquid is not particularly limited, and an oxidizing agent generally used can be used. For example, chlorine gas, ozone, hydrogen peroxide, chlorate or the like can be used, but from the viewpoint of environmental and safety, chlorate is more preferred, and sodium chlorate or potassium chlorate is more preferred. In the present invention, the regeneration management method of the etching liquid can use a management method generally used. For example, various ion concentrations, ORP, pH, specific gravity, and transparency can be measured and managed. From the viewpoint of reducing the change in the etching rate before and after the regeneration, it is preferable to repeat the regeneration reaction in a fine cycle, and it is preferable to use -15-201030185 for the detection of a high sensitivity. In the regeneration management method for measuring the transparency of the etching liquid, the apparatus for measuring the transparency is not particularly limited, and a general use such as a photoelectric photometer, a spectrophotometer, a color sensor, or a fiber sensor can be used. As the measuring method, for example, a method in which the etching liquid is frequently circulated in a flow cell or the like and is not subjected to direct contact with the etching liquid, and is measured externally is preferable. In this way, by comparing the number 値 measured on-line with the predetermined setting of the degree of management deterioration ', the wavelength of the oxidizing agent used for regeneration, which can be added in a necessary amount, is contained in the chlorine-containing phase. The iron (III) and the copper (II) chloride etching solution have a transparency peak in the range of 400 to 75 Onm. According to the method of the present invention, when a ratio of transmittances of two or more wavelengths is used, the wavelength before and after the maximum point of the transmittance peak in the wavelength range of 400 to 750 nm is used. By measuring the wavelength larger than the maximum point, the degree of deterioration of the uranium engraving caused by the dissolution of copper can be measured, and the ratio of the wavelength smaller than the maximum point can be measured, and the influence of temperature or foam can be suppressed. For example, when the maximum point exists at 550 nm, 500 nm and 600 nm or the like can be used. The selection of the wavelength for measuring the transmittance can be set at any time by the cooperation of the etching liquid. Preferably, it is only necessary to select a plurality of most suitable wavelengths for use. When measuring the transmittance, it is preferable to measure simultaneously in the same optical path. In the present invention, simultaneous measurement is performed to measure the transmittance of two or more wavelengths within 〇1 to 100 msec. As a method of simultaneous measurement, for example, a method of measuring the transmittance of a wavelength range necessary for the light-receiving portion to select only the light-receiving portion of the light-receiving portion can be used, and the necessary wavelength can be sequentially switched within the measurement range to cause light emission. Method of measurement, etc. In the regeneration management method of the present invention, the regenerated liquid to be added is a new liquid and an oxidizing agent. The new liquid system is substituted at a certain ratio by the deterioration liquid and the degree of deterioration corresponding to the uranium engraving, and various oxides or by-products generated by the etching treatment process or the regeneration reaction can be removed. The new liquid system contains iron (III) chloride and an etching solution of hydrochloric acid necessary for the regeneration reaction. If necessary, Φ can be added to form a compound of copper and an insoluble salt or a surfactant, an antifoaming agent, an alcohol, a glycol, or the like. A wet accelerator or the like is regarded as another component. In the present invention, the oxidizing agent used in the regeneration of the etching liquid is not particularly limited, and an oxidizing agent generally used can be used. For example, chlorine, ozone, hydrogen peroxide, chlorate or the like can be used, but from the viewpoint of environment and safety, chlorate is preferred, and sodium chlorate or potassium chlorate is more preferred. In the present invention, the type of the copper foil-clad substrate # used in the manufacture of the printed circuit board is not particularly limited. As the substrate, a fiber base material such as paper phenol resin, paper epoxy resin, or plastic epoxy resin may be used, or a resin such as polyester, polyimine or polytetrafluoroethylene may be used. A sheet of various thermoplastic resins such as a resin, or other various insulating plate-like or film-like materials, and as the copper foil, a copper foil made of rolled copper, electrolytic copper, or the like, or various coppers can be used. a foil made of alloy. The method of bonding the substrate to the copper foil is not particularly limited, and an adhesive such as an epoxy resin may be used to adhere the substrate to the copper foil, or the copper foil may be bonded before the resin used for the substrate is cured, and then The resin is hardened and adhered, and it can also be used for a solution of a resin or a hot melt for developing a substrate on a copper foil of 17 to 201030185, followed by removal of a solvent or cooling and solidification. In the present invention, the photoresist used in the manufacture of the printed circuit board is not particularly limited, and an alkali can be used for image removal to remove a so-called positive photoresist which forms a pattern by irradiation with light, or The development removes a so-called negative-type photoresist that is patterned by light irradiation into an uncured portion, and various photoresists of a pattern formed by screen printing or other printing methods. The etching liquid of the present invention is suitably used for etching of copper or a copper alloy. The copper alloy in the present invention means an alloy containing 50% by mass or more of copper, as an example thereof, an alloy of copper and tin (bronze), an alloy of copper and tin and phosphorus (phosphor bronze), an alloy of copper and nickel and zinc. (Zinc white copper), an alloy of copper and zinc (brass), and an alloy of copper and nickel (white copper). Further, after the etching liquid of the present invention is used, or when the overflow liquid is discarded, the step of adjusting the pH to the weak base by adding one of the most basic heavy metal treatment steps, that is, the step of adding the calcium hydroxide The iron (II) ion, iron (ΠΙ) ion, copper (D ion, copper (η) ion and oxalic acid ion of the harmful chemical species are completely settled and removed, so the treatment after use can be easily and completely It is also easy to avoid problems in labor hygiene, pollution prevention, and environmental preservation. Example (Example 1) [Preparation of etching solution] 270 g (an anhydrous is 1 gram) commercially available 40. Beauty (201030185
Baume)之氯化鐵（III) 7_Κ溶液（濃度37質量％ ) 、25 克（無水物爲20克）氯化銅（II)二水合物、14克（無 水物爲10克）草酸二水合物中，添加1公斤水，以調製 含有10質量％氯化鐵（ΙΠ) 、2質量％的氯化銅、1質 量％的草酸之蝕刻液。 [蝕刻與再生] φ 於表面上有厚度9#m的軋製銅箔之玻璃環氧基材上 ，使用正型光阻形成線（w3 )/間隙的寬度各自爲25 // m/25 //m之光阻圖型。此處，將經調整至20°C的上述蝕 刻液，使用噴射面的直徑爲14cm之全圓錐型噴嘴，以對 噴嘴的液供給壓 150kPa、噴射量 1 320mL/min，朝向上述 基材噴射而進行蝕刻。 蝕刻液的再生係在所建浴的氯化鐵（ΙΠ )之約1 0 % 被消耗的時間點，以比重成爲固定的方式，一邊調整’一 φ 邊添加必要量之10質量％的氯酸鈉水溶液、10質量％的 鹽酸水溶液、10質量％的氯化鐵水溶液而進行’重複30 次及60次的此再生處理。 圖1係藉由蝕刻法所得之圖型的剖面簡圖’ w 1係銅 箔線的頂部寬度，w2係銅箔線的底部寬度’ W3係光阻圖 型的線寬。作爲評價項目，計測當成爲w2 = W3 ( 25 a m) 時的蝕刻時間與蝕刻因數（亦簡稱E.F )。再者’ E.F係 以E.F=2x銅箔的厚度/(w2-wi)所表示的數値’表示相 對於蝕刻的深度方向之進行量而言朝橫方向的進行量之比 -19- 201030185 率，數値愈大表示底切愈被抑制，係表示良好蝕刻的指標 (實施例2〜9、比較例1〜1 3 ) 與實施例1同樣地，調製含有表1〜3中所示各組成 濃度的蝕刻液，在與實施例1同一的光阻圖型形成完後之 基板上，進行同樣的再生與蝕刻處理，進行同樣的評價。Baume) iron(III) chloride 7_Κ solution (concentration: 37% by mass), 25 g (20 g of anhydrous) copper (II) chloride dihydrate, 14 g (10 g of anhydrous) oxalic acid dihydrate In the middle, 1 kg of water was added to prepare an etching solution containing 10% by mass of ferric chloride (bismuth), 2% by mass of copper chloride, and 1% by mass of oxalic acid. [Etching and Regeneration] φ On the glass epoxy substrate of the rolled copper foil having a thickness of 9#m on the surface, the width of the positive resist formation line (w3)/gap is 25 // m/25 / /m photoresist pattern. Here, the above-described etching liquid adjusted to 20° C. was sprayed toward the substrate by using a full-cone nozzle having a diameter of 14 cm on the ejection surface, and a liquid supply pressure of 150 kPa to the nozzle and an ejection amount of 1,320 mL/min. Etching is performed. The etchant is regenerated by adding a necessary amount of 10% by mass of chloric acid while adjusting the 'one φ' at a time when about 10% of the ferric chloride (ΙΠ) of the bath to be used is consumed. This regeneration treatment was repeated 30 times and 60 times with a sodium aqueous solution, a 10% by mass aqueous hydrochloric acid solution, and a 10% by mass aqueous solution of ferric chloride. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a schematic cross-sectional view of a pattern obtained by an etching method. The width of the top of the w 1 series copper foil line, the width of the bottom of the w2 copper foil line, and the line width of the W3 system photoresist pattern. As an evaluation item, the etching time and the etching factor (also referred to as E.F.) when w2 = W3 (25 a m) were measured. In addition, the 'EF is the number 値' indicated by the thickness of EF=2x copper foil/(w2-wi), which represents the ratio of the amount of progress in the lateral direction with respect to the amount of progress in the depth direction of etching - 19-201030185 The larger the number, the more the undercut was suppressed, and the index indicating good etching (Examples 2 to 9 and Comparative Examples 1 to 1 3). The composition shown in Tables 1 to 3 was prepared in the same manner as in Example 1. The etching liquid having the same concentration was subjected to the same regeneration and etching treatment on the substrate after the formation of the same photoresist pattern as in Example 1, and the same evaluation was performed.
-20- 201030185 [表1] 蝕刻液配合 (量的表示全都以無水物換算) 蝕刻時間 蝕刻因數 建浴時 sec 再生 30次 sec 再生 60次 sec 建浴時 再生 30次 再生 60次 實施例 1 氯化鐵（皿） 10質量％ 氯化銅（Π) 2質量％ 硫脲 1質量％ 其餘部分水 115 115 115 3.5 3.5 3.5 實施例 2 氯化鐵（皿） 10質量％ 氯化銅（Π) 2質量％ 苯并三唑 1質量％ 其餘部分水 110 110 110 4.0 4.0 4.0 實施例 3 氯化鐵（皿） 10質量％ 氯化銅（Π) 2質量0/〇 草酸 1質量％ 其餘部分水 120 120 120 8.0 8.0 8.0 實施例 4 氯化鐵（m) ίο質量％ ®化銅（Π) 2質量％ 草酸 2質量％ 其餘部分水 180 180 180 12.0 12.0 12.0 實施例 5 氯化鐵（皿） ίο mm.% 氯化銅（Π) 2質量％ 草酸 0.5質量％ 其餘部分水 90 90 90 6.0 6.0 6.0 實施例 6 氯化鐵（m) 5質量％ 氯化銅（Π) 2質量％ 草酸 1質量％ 其餘部分水 200 200 200 10.0 10.0 10.0 實施例 7 氯化鐵（m) 20質量％ 氯化銅（Π) 2質量％ 草酸 1質量％ 其餘部分水 40 40 40 4.0 4.0 4.0 實施例 8 氯化鐵（Π) 10質量％ 氯化銅（Π) 0.5質量％ 草酸 1質量％ 其餘部分水 130 130 130 6.0 6.0 6.0 實施例 9 氣化鐵（皿） 10質量％ 氯化銅（Π) 3質量％ 草酸 1質量％ 其餘部分水 100 100 100 4.5 4.5 4.5 -21 - 201030185 [表2] 蝕刻液配合 (量的表示全都以無水物換算) 蝕刻時間 蝕刻因數 建浴時 sec 再生 30次 sec 再生 60次 sec 建浴時 再生 30次 再生 60次 比較例 1 氯化鐵（m) ίο質量％ 其餘部分水 60 80 85 1.2 1.4 1.5 比較例 2 氯化銅（π) 10質量％ 其餘部分水 125 140 145 1.2 1.4 1.4 比較例 3 氣化鐵（m) ίο質量％ 硫脲 1質量％ 其餘部分水 125 140 145 3.5 3.2 3.0 比較例 4 氯化鐵（ΙΠ) 10質量％ 苯并三唑 1質量％ 其餘部分水 115 135 140 4.0 3.6 3.5 比較例 5 氯化鐵（m) 10質量％ 草酸 1質量％ 其餘部分水 130 150 155 8.0 7.5 7.0 比較例 6 氯化銅（Π) 10質量％ 草酸 1質量％ 其餘部分水 發生白色沈澱物， 無法配合。 比較例 7 氣化鐵（π) ίο質量％ 氯化銅（Π) 2質量％ 其餘部分水 45 60 65 1.0 1.1 1.1 -22- 201030185 參 [表3] _ 蝕刻液配合 (量的表示全都以無水物換算) 蝕刻時間 蝕刻 因數 建浴時 sec 再生 30次 sec 再生 60次 sec 建浴時 再生 30次 再生 60次 比較例 8 氯化鐵(ΙΠ) 10質量％ 氯化銅(Π) 2質量％ 草酸 2.1質量％ 其餘部分水 蝕刻沒有進行。 比較例 9 氯化鐵(m) ίο質量％ 氯化銅(Π) 2質量％ 草酸 0.4質量％ 其餘部分水 80 80 80 2.0 1.8 2.0 比較例 10 氯化鐵(ΙΠ) 4質量％ 氯化銅(Π) 2質量％ 草酸 0.25質量％ 其餘部分水 蝕刻時間變長， 不合實用。 比較例 11 氯化鐵(ΙΠ) 21質量％ 氯化銅(H) 2質量％ 草酸 2.5質量％ 其餘部分水 35 40 40 2.0 1.8 1.8 比較例 12 氯化鐵(m) ίο質量％ 氯化銅(Π) 0.4質量％ 草酸 1質量％ 其餘部分水 145 140 120 8.5 8.0 8.0 比較例 13 氯化鐵(ΙΠ) 10質量％ 氯化銅(Π) 4質量％ 草酸 1質量％ 其餘部分水 95 110 120 7.0 7.5 8.0 -23- 201030185 如由表1可明知，本發明的蝕刻液係底切少，且即使 進行再生也蝕刻速度的變化少之蝕刻液。特別地，可知使 用草酸當作形成銅與不溶性的鹽之化合物者，係底切極少 的蝕刻液。 相對於此，如比較例1、2、7，未加有與銅形成不溶 性的鹽之化合物之蝕刻液，係幾乎沒有看到底切的抑制。 又，於未加有氯化銅（II)的比較例3、4、5中，雖然底 切被抑制，但重複再生時的蝕刻速度之變化大，安定的操 作係困難。於比較例6生，發生白色沈澱物，而無法建浴 再者，草酸的濃度在範圍外的比較例8係蝕刻沒有進 行，比較例9係底切的抑制不充分。氯化鐵（III )濃度 在範圍外的比較例1 〇係蝕刻時間長而不合實用，比較例 1 1係底切的抑制不充分。氯化銅（II )濃度在範圍外的比 較例12與13，雖然底切被抑制，但是重複再生時的蝕刻 速度之變化大，安定的操作係困難。根據以上，使用本發 明的蝕刻液才可提供能抑制底切，而且即使進行再生也蝕 刻速度的變化少之蝕刻液及蝕刻方法。 (實施例1 〇 ) [蝕刻液的調製] 於216克（無水物爲1〇〇克）市售的40°波美之氯化 鐵（III )水溶液（濃度37質量％ ) 、25克（無水物爲 2〇克）氯化銅（Π)二水合物、7克（無水物爲5克）草 -24- 201030185 酸二水合物中，添加1公斤水，以調製含有8質量％的氯 化鐵（III) 、2質量％的氯化銅、0.5質量％的草酸之蝕 刻液。 [蝕刻] 於表面上有厚度9/zm的軋製銅箔之玻璃環氧基材上 ，將經調整至30°C的上述蝕刻液，使用噴射面的直徑爲 φ 20cm的全圓錐型噴嘴，以對噴嘴的液供給壓150kPa、噴 射量1 000mL/min，朝向上述基材噴射而進行蝕刻。 [再生管理用的數値測定] 透過度係使用 OMRON公司製的數位纖維感測器 E3X-DAG-S (商品名，波長 525nm)及 E3X-NA11 (商品 名，波長6 8 Oiim )來計測。測定條件係停止蝕刻噴淋，使 蝕刻液在流池中循環的狀態下，在不同的光路同時計測。 0 ORP與pH係使用堀場製作所公司製的pH計D-52S，將 感測器浸漬在蝕刻液中而計測。 [蝕刻液的再生] 蝕刻液的再生係在所建浴的氯化鐵（III)之約5%被 消耗的時間點，以比重成爲固定的方式，一邊調整，一邊 添加必要量之10質量％的氯酸鈉水溶液、含鹽酸的8質 量％之氯化鐵水溶液，重複100次的此再生處理之循環。 表4中顯示進行再生處理的結果。 -25- 201030185 [表4] 建浴液 第1次的再生 第50次的再生 第100次的再生 劣化後 再生後 劣化後 再生後 劣化後 再生後 透過度(525nm) 3695 3563 3689 3577 3690 3544 3677 透過度(635nm) 2385 2081 2379 2011 2389 2062 2364 透過度比 (635nm/525nm) 0.645 0.584 0.645 0.562 0.647 0.582 0.643 ORP(mV) 348 348 348 347 348 349 348 PH(-) 0.55 0.56 0.55 0.55 0.55 0.56 0.56 蝕刻速度 (μιη/min) 10.5 10.4 10.6 10.5 10.5 10.3 10.4 Μ (°C) 30.0 30.2 30.5 29.8 30.4 30.2 30.3 如由表4可明知，ORP或pH在再生前後的數値係沒 有變化，劣化程度之判定爲不可能的細小循環之再生，係 可藉由測定透過度而成爲可能。因此，再生前後的蝕刻速 度亦幾乎沒有差異，再生前後的安定蝕刻係成爲可能。完 成100次的再生處理後，ORP及pH感測器由於氧化物的 附著而需要洗淨作業，用流池的透過度感測器係完全不需 要如此的維護。 (實施例1 1 ) 爲了看到在改變實施例1 〇所調製的蝕刻液之溫度時 ，透過度的變化及蝕刻液中的泡沫之影響，對蝕刻噴淋用 泵運轉前後的透過度之變化，與實施例同樣地，在不 同的光路進行同時計測，表5中顯示結果。 -26- 201030185 [表5] 蝕刻液的溫度 20°C 25〇C 30°C 35〇C 35〇C 噴淋泵 停止 停止 停止 停止 運轉 透過度(525mn) 3939 3844 3776 3564 3422 透過度(635nm) 2537 2464 2436 2295 2207 透過度比 (635nm/525nm) 0.644 0.641 0.645 0.644 0.645 如由表5可明知，在單波長的透過度之數値，雖然隨 ® 著溫度的上升而降低，但是藉由計測透過度比，則可能抑 制溫度變化的影響。又，當開動噴淋泵，而氣泡在鈾刻液 中混合存在時’在單波長的透過度之數値雖然降低，但是 藉由計測透過度比，則可能抑制氣泡的影響。 (實施例1 2 ) 使用圖2及圖3所示的計測方法，查證在同一光路內 同時計測時時的效果。圖2係在同一光路內計測時的簡圖 ，圖3係在不同光路計測透過度時的簡圖。以纖維感測器 5、7及9使發光，使透過飩刻液經常從下方到上方循環 的流池4內後，以纖維感測器6、8及10來受光。使用此 等2個計測方法，用在實施例1 0所調製的蝕刻液中加有 0.05質量％的市售之界面活性劑（商品名：Emulgen 103, 花王公司製）者，於使蝕刻液中的氣泡量增加的狀態下進 行透過度的測定，表6中顯示其結果。再者，如圖3所示 之以測定光路不同的測定方式所用的纖維感測器，係使用 與實施例1 〇所用者相同的纖維感測器來測定，如圖2所 -27- 201030185 示之以測定光路相同的測定方式所用的纖維感測器，係使 用OMRON公司製的數位纖維感測器E3MC-Y81 (商品名， 波長525nm及680nm)來計測。又，圖3所示之測定光 路不同時的纖維感測器7與9之間的距離及纖維感測器8 與1 0之間的距離爲1 〇mm。透過度的測定係以1秒間隔 進行20次，當計測時間不同時，使用慢1秒測定低波長 側的透過度時之透過度比。-20- 201030185 [Table 1] Etching solution (the amount is expressed in terms of anhydrous). Etching time Etching factor sec regeneration 30 times sec regeneration 60 times sec regeneration 30 times regeneration 30 times in the bath. Example 1 Chlorine Iron (dish) 10% by mass Copper chloride (Π) 2% by mass Thiourea 1% by mass The rest of the water 115 115 115 3.5 3.5 3.5 Example 2 Ferric chloride (dish) 10% by mass Copper chloride (Π) 2 Mass % Benzotriazole 1% by mass The rest of the water 110 110 110 4.0 4.0 4.0 Example 3 Ferric chloride (dish) 10% by mass Copper chloride (Π) 2 mass 0 / shikimic acid 1% by mass The rest of the water 120 120 120 8.0 8.0 8.0 Example 4 Ferric chloride (m) ί mass% ® copper (Π) 2% by mass oxalic acid 2% by mass The rest of the water 180 180 180 12.0 12.0 12.0 Example 5 Ferric chloride (dish) ίο mm. % Copper chloride (Π) 2% by mass Oxalic acid 0.5% by mass The rest of the water 90 90 90 6.0 6.0 6.0 Example 6 Ferric chloride (m) 5 mass% Copper chloride (Π) 2% by mass Oxalic acid 1% by mass The rest Water 200 200 200 10.0 10.0 10.0 Example 7 Ferric chloride (m) 20 quality % copper chloride (Π) 2% by mass oxalic acid 1% by mass The rest of the water 40 40 40 4.0 4.0 4.0 Example 8 Ferric chloride (Π) 10% by mass Copper chloride (Π) 0.5% by mass Oxalic acid 1% by mass The rest Water 130 130 130 6.0 6.0 6.0 Example 9 Gasified iron (dish) 10% by mass Copper chloride (Π) 3% by mass Oxalic acid 1% by mass The rest of the water 100 100 100 4.5 4.5 4.5 -21 - 201030185 [Table 2] Etching Liquid mixture (the amount is expressed in terms of anhydrous matter) Etching time Etching factor sec regeneration 30 times sec regeneration 60 times sec regeneration 30 times regeneration 30 times in the bath. Comparative example 1 Ferric chloride (m) ίο质量% Partial water 60 80 85 1.2 1.4 1.5 Comparative Example 2 Copper chloride (π) 10% by mass The rest of the water 125 140 145 1.2 1.4 1.4 Comparative Example 3 Gasified iron (m) ίο% by mass Thiourea 1% by mass The remaining part of water 125 140 145 3.5 3.2 3.0 Comparative Example 4 Ferric chloride (ΙΠ) 10% by mass Benzotriazole 1% by mass The rest of the water 115 135 140 4.0 3.6 3.5 Comparative Example 5 Ferric chloride (m) 10% by mass Oxalic acid 1% by mass Others Partial water 130 150 155 8.0 7.5 7.0 Comparative Example 6 cupric chloride (Π) 10% by mass oxalic acid aqueous 1 mass% the rest of the white precipitate occurred, can not fit. Comparative Example 7 Vaporized iron (π) ίο% by mass Copper chloride (Π) 2% by mass The rest of the water 45 60 65 1.0 1.1 1.1 -22- 201030185 Reference [Table 3] _ Etching solution (quantity means all without water Material conversion) Etching time Etching factor sec regeneration 30 times sec Regeneration 60 times sec Regeneration 30 times regeneration 60 times in the bath. Comparative Example 8 Ferric chloride (ΙΠ) 10% by mass Copper chloride (Π) 2% by mass Oxalic acid 2.1% by mass The remaining part of the water etching did not proceed. Comparative Example 9 Ferric chloride (m) ί mass% copper chloride (Π) 2% by mass oxalic acid 0.4% by mass The remaining portion of water 80 80 80 2.0 1.8 2.0 Comparative Example 10 Ferric chloride (ΙΠ) 4% by mass Copper chloride ( Π) 2% by mass oxalic acid 0.25 mass% The rest of the water etching time becomes longer and is not practical. Comparative Example 11 Ferric chloride (ΙΠ) 21% by mass Copper chloride (H) 2% by mass Oxalic acid 2.5% by mass Other water 35 40 40 2.0 1.8 1.8 Comparative Example 12 Ferric chloride (m) ί mass% Copper chloride ( Π) 0.4% by mass oxalic acid 1% by mass The rest of the water 145 140 120 8.5 8.0 8.0 Comparative Example 13 Ferric chloride (ΙΠ) 10% by mass Copper chloride (Π) 4% by mass oxalic acid 1% by mass The rest of the water 95 110 120 7.0 7.5 8.0 -23-201030185 As is apparent from Table 1, the etching liquid of the present invention has an undercut and a etching liquid having a small change in etching rate even if it is regenerated. In particular, it has been found that oxalic acid is used as a compound for forming copper and an insoluble salt, and is an etching liquid having few undercuts. On the other hand, as in Comparative Examples 1, 2, and 7, an etching solution in which a compound having an insoluble salt with copper was not added was observed, and almost no undercut was observed. Further, in Comparative Examples 3, 4, and 5 in which copper (II) chloride was not added, although the undercut was suppressed, the change in the etching rate during the repeated regeneration was large, and the stable operation was difficult. In Comparative Example 6, a white precipitate occurred and the bath could not be formed. Further, in Comparative Example 8 in which the concentration of oxalic acid was outside the range, etching was not performed, and in Comparative Example 9, the undercut was insufficiently suppressed. Comparative Example 1 in which the concentration of iron (III) chloride was out of the range The lanthanide etching time was long and practical, and the suppression of undercut in Comparative Example 1 was insufficient. In Comparative Examples 12 and 13 in which the concentration of copper (II) chloride was out of the range, although the undercut was suppressed, the change in the etching rate during the repeated regeneration was large, and the stable operation was difficult. According to the above, the etching liquid and the etching method which can suppress the undercut and which have little change in the etching speed even if the regeneration is performed can be provided by using the etching liquid of the present invention. (Example 1 〇) [Preparation of etching liquid] 216 g (1 g of anhydrous) commercially available 40° Bomei iron (III) aqueous solution (concentration: 37% by mass), 25 g (anhydrous) 2 grams of copper chloride (Π) dihydrate, 7 grams (5 grams of anhydrate) grass-24- 201030185 acid dihydrate, adding 1 kg of water to prepare 8% by weight of chlorination An etching solution of iron (III), 2% by mass of copper chloride, and 0.5% by mass of oxalic acid. [Etching] On the glass epoxy substrate having a rolled copper foil having a thickness of 9/zm on the surface, the above etching liquid adjusted to 30 ° C was used, and a full-cone nozzle having a diameter of φ 20 cm on the ejection surface was used. The liquid supply pressure to the nozzle was 150 kPa, and the injection amount was 1 000 mL/min, and the substrate was sprayed and etched. [Measurement of number for regeneration management] The transmittance was measured using a digital fiber sensor E3X-DAG-S (trade name, wavelength 525 nm) and E3X-NA11 (trade name, wavelength 6 8 Oiim) manufactured by OMRON. The measurement conditions are such that the etching is stopped and the etching liquid is circulated in the flow cell, and the measurement is performed simultaneously on different optical paths. 0 ORP and pH were measured using a pH meter D-52S manufactured by Horiba, Ltd., and the sensor was immersed in an etching solution. [Regeneration of the etchant] The etchant is regenerated in such a manner that approximately 5% of the ferric chloride (III) in the bath is consumed, and the specific gravity is fixed, and 10% by mass of the necessary amount is added while being adjusted. The sodium chlorate aqueous solution and the 8% by mass aqueous solution of hydrochloric acid containing hydrochloric acid were repeated for 100 cycles of this regeneration treatment. The results of the regeneration treatment are shown in Table 4. -25- 201030185 [Table 4] The first time of the reconstitution of the bath, the 50th regeneration, the 100th regeneration, the post-regeneration, the post-regeneration, the post-regeneration, the post-regeneration, and the post-regeneration transmittance (525 nm) 3695 3563 3689 3577 3690 3544 3677 Transmittance (635nm) 2385 2081 2379 2011 2389 2062 2364 Transmittance ratio (635nm/525nm) 0.645 0.584 0.645 0.562 0.647 0.582 0.643 ORP(mV) 348 348 348 347 348 349 348 PH(-) 0.55 0.56 0.55 0.55 0.55 0.56 0.56 Etching Speed (μιη/min) 10.5 10.4 10.6 10.5 10.5 10.3 10.4 Μ (°C) 30.0 30.2 30.5 29.8 30.4 30.2 30.3 As can be seen from Table 4, the ORP or pH does not change before and after regeneration, and the degree of deterioration is judged as The regeneration of an impossible small cycle is made possible by measuring the transmittance. Therefore, there is almost no difference in the etching speed before and after the regeneration, and stable etching before and after the regeneration is possible. After 100 cycles of regeneration, the ORP and pH sensor require cleaning due to the adhesion of the oxide. The flow sensor of the flow cell does not require such maintenance. (Example 1 1) In order to see the change in the degree of transparency of the etching liquid prepared in Example 1, the change in the transmittance and the influence of the foam in the etching liquid, the change in the transmittance before and after the operation of the etching pump In the same manner as in the examples, simultaneous measurement was performed on different optical paths, and the results are shown in Table 5. -26- 201030185 [Table 5] Etching liquid temperature 20 °C 25〇C 30 °C 35〇C 35〇C Spray pump stop stop stop stop operation transparency (525mn) 3939 3844 3776 3564 3422 Transmittance (635nm) 2537 2464 2436 2295 2207 Transmittance ratio (635nm/525nm) 0.644 0.641 0.645 0.644 0.645 As can be seen from Table 5, the number of transmittances at a single wavelength decreases with increasing temperature, but is measured by The ratio is proportional to the effect of temperature changes. Further, when the shower pump is activated and the bubbles are mixed in the uranium engraving liquid, the number of transmittances at a single wavelength decreases, but by measuring the transmittance ratio, the influence of the bubbles may be suppressed. (Embodiment 1 2) Using the measurement method shown in Figs. 2 and 3, the effect at the time of simultaneous measurement in the same optical path was examined. Fig. 2 is a simplified diagram when measuring in the same optical path, and Fig. 3 is a simplified diagram when measuring transmittance in different optical paths. The light is emitted by the fiber sensors 5, 7, and 9, and the light is received by the fiber sensors 6, 8 and 10 after passing through the flow cell 4 through which the etching liquid is often circulated from below to above. Using these two measurement methods, 0.05% by mass of a commercially available surfactant (trade name: Emulgen 103, manufactured by Kao Corporation) was added to the etching solution prepared in Example 10 to make an etching solution. The measurement of the transmittance was carried out in a state where the amount of bubbles was increased, and the results are shown in Table 6. Further, the fiber sensor used in the measurement method in which the measurement optical path is different as shown in FIG. 3 is measured using the same fiber sensor as that used in the embodiment 1, as shown in FIG. 2, -27-201030185. The fiber sensor used for measuring the same optical path was measured using a digital fiber sensor E3MC-Y81 (trade name, wavelength: 525 nm and 680 nm) manufactured by OMRON. Further, the distance between the fiber sensors 7 and 9 at the time when the measurement paths are different as shown in Fig. 3 and the distance between the fiber sensors 8 and 10 are 1 〇 mm. The measurement of the transmittance was performed 20 times at intervals of 1 second. When the measurement time was different, the transmittance ratio at the low-wavelength side was measured using a slow one second.
[表6] 蝕刻液的溫度 35〇C 35〇C 35〇C 35〇C 賁淋泵 運轉 運轉 運轉 運轉 纖維感測器 不同 同一 不同 同一 計測時間 不同 不同 同一 同一 計測方法 圖3 圖2 圖3 圖2 透過度比(635nm/525nm) 最大値 0.673 0.666 0.651 0.647 透過度比(635nm/525nm) 最小値 0.596 0.613 0.622 0.639 透過度比(635mn/525nm) (最大値-最小値） 0.077 0.053 0.029 0.008[Table 6] The temperature of the etching solution is 35〇C 35〇C 35〇C 35〇C The pump is running and running. The fiber sensor is different. The same measurement time is different. The same measurement method is the same. Figure 3 Figure 2 Figure 3 2 Transmittance ratio (635nm/525nm) Maximum 値0.673 0.666 0.651 0.647 Transmittance ratio (635nm/525nm) Minimum 値0.596 0.613 0.622 0.639 Transmittance ratio (635mn/525nm) (maximum 値-min 値) 0.077 0.053 0.029 0.008
如由表6可明知，在測定透過度時於同—光路內同時 計測的本發明之測定方法，係更抑制泡沬的影響之測定方 法。當計測時間不同時，透過度比係變成在上下更大幅地 振盪’在不同光路 '不同計測時間所求得的透過度比之振 盪範圍亦變成最大。 -28- 201030185 產業上的利用可能性 本發明的蝕刻液、蝕刻方法及再生管理方法不僅適用 於印刷電路板的製造，而且適用於塑膠基板上的配線、塑 膠基板表面的配線、半導體表面的配線等各種配線之形成 ，在其它各種產業用途中，亦可適用於需要高度經控制的 銅或銅合金之蝕刻的場合。 CI 【圖式簡單說明】 圖1係藉由蝕刻法所得之圖型的剖面簡圖。 圖2係在同一光路內同時計測透過度的簡圖。 圖3係在不同光路計測透過度的簡圖。 【主要元件符號說明】As is clear from Table 6, the measurement method of the present invention which is simultaneously measured in the same optical path when measuring the transmittance is a method for further suppressing the influence of the bubble. When the measurement time is different, the transmittance ratio becomes larger and larger, and the oscillation range obtained by the different measurement times of the different optical paths becomes larger than the oscillation range. -28- 201030185 INDUSTRIAL APPLICABILITY The etching liquid, etching method, and regeneration management method of the present invention are applicable not only to the manufacture of printed circuit boards, but also to wiring on plastic substrates, wiring on the surface of plastic substrates, and wiring on semiconductor surfaces. The formation of various wirings can also be applied to the etching of highly controlled copper or copper alloys in various other industrial applications. CI [Simple description of the drawing] Fig. 1 is a schematic sectional view of a pattern obtained by an etching method. Figure 2 is a simplified diagram of simultaneous measurement of transmittance in the same optical path. Figure 3 is a simplified diagram of the measured transmittance at different optical paths. [Main component symbol description]
Wi :銅箔線的頂部寬度 W2:銅箔線的底部寬度 A W3 :光阻的線寬 1 :光阻 2 :銅箔 3 :基材 4 :流池 5、 7、9 :纖維感測器（發光部） 6、 8，10:纖維感測器（受光部） -29-Wi: top width W2 of copper foil wire: bottom width of copper foil wire A W3: wire width of photoresist 1: photoresist 2: copper foil 3: substrate 4: flow cell 5, 7, 9 : fiber sensor (Light-emitting part) 6, 8, 10: Fiber sensor (light-receiving part) -29-