201043917 六、發明說明： 【發明所屬之^技術^領城】 發明領域 本發明係有關於一種用以測量要雷射加工之半導體晶 圓等工作件表面之高度位置的高度檢測裝置。 Γ先前技^軒】 發明背景201043917 VI. Description of the Invention: [Technical Field] The present invention relates to a height detecting device for measuring the height position of a surface of a workpiece such as a semiconductor wafer to be laser processed. ΓPrevious skills ^ Xuan] Background of the invention
Ο 在半導體讀製程中，以於略呈圓板狀之半導體工作 件表面排列成格子狀之切割道(分割預定線）劃分複數個區 域將於此所劃分之區域形成有Ic、LSI等電路之半導體工 :件化者切^道切斷’而就各電路分割，而可製造諸個半 :體片。/口者半導體工作件之切割道所作之切斷通常以稱 補裝置進行’亦嘗試了照射雷射光束而切斷 方法已提出#、、H+ D BaB1等卫作件沿著切割道分割之 脈衝雷射光;之波長之 與外力而騎之鄉喻加工溝賊 又，亦嘗試使用對工作 ：)。 光束，使聚光點對準要分 β遇1·生之波長之脈衝雷射 之雷射加J1方法。使用 ^❿照射脈衝雷射光束 匕霄射加丁戈-^ 1 作件之-面側使聚光點對準内之分割方法係從工 之波長之脈衝雷射光束，而於:作:=，作件具穿透性 切割道之改質層，藉沿著因形成此續形成沿著 、層而強度降低之切 201043917 割道施加外力，將工作件分割者(例如參照專利文獻2)。 然而，晶圓等板狀工作件有彎曲，工作件之表面高度 位置非一定。因此，為在上述任一加工方法，於賦與外力 時皆可以良好品質將工作件分割成晶片，乃需藉檢測工作 件表面之高度位置，依據該檢測結果，於雷射加工時，修 正雷射光束之焦點位置，而將雷射加工溝及改質層均一地 形成。因此，提出了使用白光，檢測工作件表面之高度位 置之檢測裝置（例如參照專利文獻3)。即，藉利用通過色像 差透鏡之白光具有因波長而異之焦點距離，界定穿透針孔 之反射光之波長，而求出焦點距離，而量測工作件之表面 高度位置。 先行技術文獻 專利文獻 專利文獻1日本專利公開公報平10-305420號 專利文獻2曰本專利公報第3408805號 專利文獻3日本專利公開公報2008-170366號 【發明内容】 發明概要 發明欲解決之課題 以該等提出例，可以良好精確度量測工作件表面之高 度位置。然而，使用繞射，使光依各波長色散時，引起相 鄰之階數之光譜一部份相互重疊的現象，故僅可利用於檢 測不產生重疊之自由光譜區域之波長。即，可利用於檢測 之波長帶受限。 201043917 本發明即係鑑於上述而發明者，其係以提供於使用繞 射0^·可將所期之階數之繞射光的所有波長利用於檢測之 '高度檢測裝置為目的。 用以欲解決課題之手段 為解決上述課題，達成目的，本發明之高度檢測裝置 係褒備於加工機’而檢測保持在保持機構之工作件之高度 的南度檢測裝置，其特徵在於包含有使白光發光之白光 0 源、將前述白光所含之各波長分別聚光 ，而於朝向前述工 作件之光軸上形成複數個聚光點之色像差透鏡、及檢測以 该色像差透鏡聚光後以前述工作件所反射之反射光之高度 檢測機構；前述高度檢測機構具有限制以前述工作件表面 所反射之光中在該工作件表面附近連結焦點之光以外的光 之通過之光限制機構、使通過該光限制機構之前述反射光 分歧成在同一平面内擴展之繞射光的繞射光學元件、及在 前述繞射光所含之預定η階繞射光(η係整數)及與該η階階數 Q 不同之異階繞射光中僅檢測前述η階繞射光之η階繞射光檢 測機構；該η階繞射光檢測機構具有將包含前述…皆繞射光 與前述異階繞射光之前述繞射光聚光之繞射光聚光透鏡、 使包含以前述繞射光聚光透鏡聚光之前述η階繞射光與前 述異階繞射光之前述繞射光以因各角度而異之角度往前述 同一平面外之方向折射的色散濾波器、在以該色散濾波器 集光於因各波長而異之處之前述η階繞射光與前述異階繞 射光中僅於前述η階繞射光聚光之處具有檢測部，而僅檢測 前述η階繞射光之各波長的光強度之波長檢測感測器、及用 201043917 以儲存記憶有以前述色像差透鏡聚光之前述白光所含之各 波長的焦點距離之控制圖之記憶體；該高度檢測裝置可依 據前述波長檢測感測器之信號及前述控制圖，求出保持在 前述保持機構之前述工作件的高度位置。 發明效果 根據本發明，可提供於使用繞射時，可將所期之階數 之繞射光的所有波長利用於檢測之面度檢測裝置。 圖式簡單說明 第1圖係顯示裝備有本發明實施形態之高度檢測裝置 之雷射加工裝置之主要部份的外觀立體圖。 第2圖係顯示用於該雷射加工裝置之加工之工作件的 立體圖。 第3圖係概略地顯示本實施形態之高度檢測裝置之結 構圖。 第4圖係顯示聚光位置之情形之模式圖。 第5圖係將第3圖中之A部份放大而顯示的結構圖。 第6圖係將第3圖中之B部份放大而顯示的結構圖。 第7(a)圖、第7(b)圖係顯示與工作件保持在保持機構之 預定位置之狀態之座標位置的關係之說明圖。 C實施方式3 用以實施發明之形態 以下，就用以實施本發明之形態之高度檢測裝置，參 照圖式來說明。本實施形態係顯示將於以排列成格子狀之 複數個切割道所劃分之複數個區域形成有器件之半導體晶 201043917 圓荨工作件作為檢 裝置搭载至為沿著切”對而檢測其高度位置之高度檢測 施以雷射加工之力二工作件照射加工用雷射光束而 射二C本實施形態之高度檢測裝置之雷 雷射加工裝置之加#的外觀立體圖，第2圖係顯示用於該 射加工襄置20包含作件的立體圓。本實施形態之雷 保持機助、對保持在保持工作件1之保持面仏之 1照射脈衝狀加w雷射光束之簡面21a上之工作件 保持在保持機構21之保持—上之工作 ’、’、《測對象，而檢測其表面之高度位置之高度檢測裝 置。又，保持機構21吸引保持工作们，並 筒部_之圖中未示之馬如設成可旋轉。 首先，如第2圖所示，作為加工對象之工作件砩以表 面la為上側而_於裝設在環狀框於，由聚烯等合成樹脂 片構成之切_帶3之狀態而準備。此種工作件1未特別限 定，舉例吕之，有半導體晶圓等晶圓、作為晶片安裝用而 設於晶圓裡面之DAF(Die Attach Film)等黏著構件、或者半 導製品之封裝、陶瓷、玻璃系或矽系基板、甚至是要求"爪 等級之精確度之各種加工材料。本實施形態之工作件丨以半 導體晶圓為基底，形成以於表面la排列成格子狀之於χ轴方 向延伸的複數個第1切割道4a、於Υ軸方向延伸之複數個第2 切割道4b劃分之複數個矩形區域，於此複數個矩形區域形 成器件5。 201043917 又，保持機構21搭載於2段之滑動塊25、26上。保持機 構21對滑動塊25設成可藉以滾珠螺桿27、螺帽（圖中未示）、 脈衝馬達28等構成之加工進給機構29於為水平方向之X細 方向移動，而使所搭載之工作件1對加工用雷射光束照射機 構22照射之脈衝雷射光束相對地加工進給。保持機構21同 樣地對滑動塊26設成可藉以滾珠螺桿30、螺帽（圖中未示卜 脈衝馬達31等構成之分度進給機構32於為水平方向之γ料 方向移動，而使所搭載之工作件1對加工用雷射光束照射機 構22照射之脈衝雷射光相對地分度進給。 在此，對加工進給機構29附設有用以檢測保持機構21 之加工進給量之加工進給量檢測機構33。加工進給量檢測 機構33由沿著X軸方向配設之線性標度33a、配設於滑動塊 25，而隨著滑動塊25—同沿著線性標度33a移動之圖中未示 之讀取頭組成。此加工進給量檢測機構33藉每1 # m將1脈衝 之脈衝信號送至圖中未示之控制機構，此控制機構計數所 輸入之脈衝信號，而檢測保持機構21之加工進給量。 同樣地’對分度進給機構32附設有用以檢測保持機構 21之分度進給量之分度進給量檢測機構34。分度進給量檢 測機構3 4由沿著γ軸方向配設之線性標度3 4 &、配設於滑動 塊26，而隨著滑動塊26—同沿著線性標度34a移動之圖中未 示之讀取頭組成。此分度進給量檢測機構34藉每lym將1 脈衝之脈衝信號送至圖中未示之控制機構，此控制機構計 數所輸入之脈衝信號，而檢測保持機構21之分度進給量。 又，加工用雷射光束照射機構22係具有實質上水平配 201043917 置之殼體35 ’以此殼體35為中介，對支撐塊36設成可以圖 中未不之Z軸移動機構，於Z轴方向移動。加工用雷射光束 照射機構22具備配設於殼體35内之圖中未示之雷射振盪機 構及傳送光學系統、配設於殼體35之前端，將以雷射光束 振盪機構所振盪之脈衝狀加工用雷射光束對保持在保持機 構21之工作件丨照射的聚光器39。雷射光束振盪機構以由 YAG雷射振盪器或γν〇4雷射振盪器組成之雷射振盪器等 0 構成。於聚光器39内設有用以對工作件1聚光照射加工用雷 射光束之加工用聚光透鏡。又，對加工用聚光透鏡設有以 高速進行Ζ軸方向之對焦之微調整的ζ軸用透鏡致動器。 又，裝设於殼體35之前端部之高度檢測裝置1〇〇係用以 在作為保持於保持機構21之保持面21a上之工作件丨的加工 對象之切割道上在加工用雷射光束照射機構22之前，先照 射檢測光，而檢測切割道上之表面高度位置者。表面高度 之檢測係為了藉即使工作件i之表面政高度位置變動，仍 〇 冑加工时射光束之聚光位置對準表面la之高度位置，而 可形成良好之雷射加工溝之故。以高度檢測裝 置100檢測出 之表面高度位置之資訊送至控制機構，而於該切割道之雷 射加工之際，供用以進行對工作件m射加工用雷射光束之 聚光器39内的圖中未示加工用聚光透鏡之對焦之ζ軸用透 鏡致動器的控制用。 第3圖係概略地顯示本實施形態之高度檢測裝置1〇〇之 結構圖，第4圖係顯示聚光位置之情形之模式圖，第5圖係 將第3圖中之A部份放大而顯示的結構圖，第6圖係將第瑁 9 201043917 中之B部份放大而顯示的結構圖。本實施形態之高度檢測裝 置100主要包含有白光源1〇1、色像差透鏡1〇2、及高度檢測 機構120。 白光源101係使含有複數個波長光之白光發光的光 源，可使用鎢絲燈、鹵素燈、白色led等。在本實施形態 中使用li素燈。色像差透鏡102係用以使從白光源101發出 之白光朝保持機構21之保持面21 a (工作件1)側聚光照射 者。在此’此色像差透鏡102係就白光所含之各波長朝工作 件1側於光軸上形成複數個焦點之聚光透鏡。即，由於以色 像差透鏡102聚光之白光折射率因波長而異，故焦點距離因 波長而異。此種色像差透鏡102使用開口數ΝΑ=0·68、視野 角WD=l_56mm之非球面透鏡。 在此，於白光源101與色像差透鏡1〇2間依序配置有準 直透鏡105、聚光透鏡1〇6、照射側光纖107、準直透鏡1〇8。 照射側光纖107係形成第1光程109a，關於從白光源1〇1射出 之白光，僅使色像差透鏡102所需之白光穩定地傳播者。 又’準直透鏡105、聚光透鏡1〇6係使從白光源101發出之白 光平行光束化後聚光而以良好效率入射至照射側光纖1〇7 之入射端部的透鏡，皆使用抑制了色像差之影響之透鏡。 又’於照射側光纖107之射出端側設有與光纖121之入射端 側一體化之光纖耦合器110，並與共通光纖ιη連結。設於 此共通光纖111與色像差透鏡1〇2間之準直透鏡1〇8係抑制 用以使經由照射側光纖1〇7，從共通光纖111射出之白光平 行光束化後，將之引導至色像差透鏡1〇2的色像差之影響之 10 201043917 透鏡。 又向度檢測機構120係依據以色像差透鏡1 〇2聚光後 以工作件1之表面反射之白光的反射光，檢測工作件丨之表 面高度位置者。此高度檢測機構主要具有光纖12卜繞射光 學元件122、及丨階繞射光檢測機構130。光纖121係形成與 第1光程109a不同之第2光程l〇9b，而用以限制在以工作件1 表面反射之白光之反射光中在工作件丨表面附近連結焦點 之光以外之光的通過之光限制機構。在此，限制係不僅指 使光完全不通過之情形，亦包含一部份不通過之情形。光 纖107、111、121由纖核及纖殼組成，例如使用纖核徑5〇#m 之多模光纖。 又，繞射光學元件122係用以轉換成對應於通過光纖 121之反射光具有之波長成份之檢測用繞射光的繞射光 柵。因此，本實施形態之繞射光學元件122將以光纖ΐ2ι引 導至第2光程l〇9b後以光纖121射出端之準直透鏡123平行 化之反射光分散成在同一平面内、例如γζ平面内擴展之繞 射光。此外，準直透鏡123亦係抑制了色像差之影響之透鏡。 又，1階繞射光檢測機構130係用以在以繞射光學元件 122所分歧之繞射光所含之1階繞射光與2階繞射光等高階 繞射光中’僅檢測1 Ps繞射光之檢測機構，而設為η階繞射 光檢測機構。此1階繞射光檢測機構130主要具有繞射光聚 光透鏡131、色散濾波器132、波長檢測感測器133、記憶體 134、表面高度位置運算部135。 繞射光聚光透鏡131係用以使包含為繞射光學元件122 201043917 所分歧之1階繞射光(η階繞射光)及高階繞射光(異階繞射光) 之繞射光朝波長檢測感測H 133聚光者。又，色散濾波 器132 係用以使包含以繞射光聚光透鏡131聚光之丨階繞射光及高 階繞射光之繞射光以因各波長而異之角度折射，俾使該繞射 光於繞射光學元件122使其分歧之Υζ平面（同—平面）外之方 向、亦即X軸方向具擴展之光學元件，可使料如棱鏡等。 又，波長檢測感測器133係在以色散濾波器132集光於 因各波長而異之處之1階繞射光與高階繞射光中僅於丨階繞 射光聚光之處具有檢測部，而僅檢測1階繞射光之各波長的 光強度者。即’波長檢測感測器133藉將為繞射光學元件122 所分歧後以繞射聚光透鏡131入射至隨波長而異之位置之 繞射光中以檢測部僅接收1階繞射光，而檢測各波長之光強 度。此波長檢測感測器133可使用可檢測以繞射聚光透鏡131 聚光之繞射光之波長的CCD線型感測器、CMOS感測器等。 在此’就經由繞射光學元件122、繞射聚光透鏡131及 色散濾波器132而於波長檢測感測器133聚光之繞射光的聚 光位置之情形，參照第4圖來說明。舉例言之，以白光為基 礎之1階繞射光要使用400〜lOOOnm之波長區域時，經由繞 射光學元件122、繞射聚光透鏡131之1階繞射光之各波長光 400、500、600、700、800、900、lOOOnm如第 3 圖所示，分 歧成於在同一平面（YZ平面）内對應於波長之位置擴展後聚 光。此時’作為高階繞射光之為相鄰階數光之2階繞射光的 光譜之一部份重疊於1階繞射光之長波長側光譜。具體言 之，經由繞射光學元件122、繞射聚光透鏡131之2階繞射光 12 201043917 之波長光400、500nm係聚光於分別在同一平面内（YZ平面） 内幾乎重疊於1階繞射光之800、lOOOnm之位置。結果，無 法在波長檢測感測器133，區分1階繞射光800nm與2階繞射 光400nm、1階繞射光lOOOnm與2階繞射光500nm之區別，而在 波長700nm以下之1階繞射光之自由光譜區域使用受到限制。 因此，在本實施形態中，附加色散濾波器132，使1階 繞射光與2階繞射光以因各波長而異之角度折射至繞射光 122使其分歧之γζ平面（同一平面）外之方向，而如第4圖所 示’於X軸方向具2維之擴展，而可進行1階繞射光與2階繞 射光之判別。波長檢測感測器133之檢測部133a配設成在以 色散濾波器132於因各波長而異之處聚光之1階繞射光與2 階繞射光（高階繞射光）中僅於1階繞射光聚光之處具靈敏 度。藉此，在檢測部133a無1階繞射光與2階繞射光重疊之區 域，所期之1階繞射光可使用400〜l〇〇〇nm之波長區域全域。 又’表面高度位置運算部135係參照預先設定以色像差 透鏡102聚光之白光所含之各波長光的焦點距離與工作件j 之表面高度之關係而儲存於記憶體丨3 4之控制圖，依據波長 檢測感測器133之檢測結果，算出工作件w之表面高度位 置，而取得高度位置資訊者。此外，設定各波長之焦點距 離而儲存於記憶體134之控制圖係預先測量z轴高度（工作 件1之表面la之高度位置）與以波長檢測感測器丨333檢測之 峰值檢測波長的關係而取得者。 接著，就本實施开> 態之工作件1之表面la之高度位置的 檢測原理作說明。從白光源101發出之白光藉由光纖1〇7、 13 201043917 m從光纖端輸出，以準直透鏡108形成平行光束後，通過 色像差透鏡102，而集光於工作件1之表面la上。以表面13 反射之白光在光程逆行，此時，在工作件丨之表面ia對焦之 光僅為特定波長之光。是故，在白光中於表面丨續焦之光 可最強地再結合於共通光纖m(光纖121)之小徑之纖核，其 他波長之光好不再結合於共通錢lu(光纖叫之纖核 而被遮斷。 藉此，再結合於共通光纖m(光纖121)之纖核之已對焦 之波長的光藉光纖121以良好效率引導至檢測機構12〇中之 繞射光學元件122側。然後，以繞射光學元件122分歧成在 預疋YZ平φ㈣狀賴光。已分歧之繞射储繞射聚光 透鏡131以對應於波長之角度以波長檢測感測器丨33聚光。 此時，有以繞射聚光透鏡131聚光之繞射光除了丨階繞射光 外’也包含2階繞射光之情形，而藉經由色散濾波器出，i 階繞射光與2階繞射光以隨波長而異之角度往相對於預定 YZ平面而在辦面外之χ軸方向折射。然後，僅”皆繞射 光為波長檢測❹!器133之_部咖所接收。此波長檢測 感測器133測量所接收之光(1階繞射光)之〉皮長，|出該測量 波長之峰值，而可檢測於工作件丨之表面la對焦之光的波長。 是故’表面高度位置運算部135藉從波長檢測感測器 133取得峰值波長之資訊作為檢測結果，參照儲存於記憶體 134之控制圖’可算出目前之工作件丄之表面^之高度位 置’而取得高度位置資訊。在此，由於使用了分光器之波 長檢測感測如3可以取樣率lkHz以上之高速依序取得峰 201043917 值波長資訊，故例如工作件1以6〇〇111111/3之速度移動時，可 在各切割道SI、S2上以〇.6mm間隔進行工作件1之表面13之 而度測量。 又，在本實施形態中，由於以色像差透鏡102使白光聚 光，而朝向保持面21a側照射，故相較於使用單一波長光之 情形，即使工作件丨之表面la之高度有偏差，仍有焦點之峰 值功率必定返回之點，故可以高精確度檢測表面la之高度 位置。 就此點，參照第5圖，進一步詳細說明。如前述，從白 光源101發出之白光通過色像差透鏡1〇2朝向保持在保持機 構21之保持面21a上之工作件1照射。此時，色像差透鏡1〇2 之所通過之白光具有因波長而異之焦點距離。即，此色像 差透鏡102就白光所含之各波長朝工作件丨於光軸上形成複 數個焦點。是故，如第5圖所示，在色像差透鏡102之光軸 中心正下方之範圍L就白光所含之各波長存在無數焦點。因 而，為使工作件1之表面la存在於無數之焦點存在之此範圍 L内，而照射白光時，不因工作件1之表面la之高度位置的 偏差’對焦後反射之光必定存在’而可確實地檢測工作件1 之表面la之高度位置。 此外’關於顯示焦點之偏差之範圍L，可根據色像差透 鏡102之開口數NA、材質、或使用繞射透鏡作為色像差透 鏡102等之對應，自由設計從數/zm至數mm。 又’以工作件1之表面la反射之光在光程逆行，而入射 至共通光纖11U光纖121)。此時，由於以未對焦之保持面21a 15 201043917 荨反射之光不易再結合於共通光纖111，入射光量少，故以 波長檢測感测器133檢測之光強度縮小。另一方面，在白光 中’不因工作件1之表面la之高度位置的偏差，以對焦狀態 照射至表面la附近之波長之光如第6圖所示’可最強地再結 合於為共通光纖111之纖殼11 lb所包圍之纖核111a。藉此， 以共通光纖111(光纖121)引導至第2光程109b後以波長檢測 感測益13 3檢測之光強度增大。 如此’根據本實施形態’由於使以工作件丨之表面13反 射之白光以纖核徑50"!：!之共通光纖1U(光纖121)引導而 入射至波長檢測感測器133側，故作為空間濾波器之精確度 高，配置之自由度高。 接著，就包含有上述高度檢測裝置100之雷射加工裝置 20之作用作說明。冑工作件丨載置於保持機構21之保持面 21a上，而予以吸引保持。然後，將吸引保持有工作件1之 保持機構21定位於圖中未示之拍攝機構之正下方，執行用 以檢測工作件i之要雷射加工之加工區域之校準作業。即， 執行用以進行形狀工作件丨之預定方向之第丨切割道如與 沿著此第1切割道4a在聚光n39内之圖中未示之加工用聚 光透鏡的雜之型觀配㈣像處理，㈣行校準。關於 第2切割道4b亦相同。 當如此進行，進行校準時，保持機構21上之工作件1 定位於如第7⑷圖所示之座標位置之狀態。第7圖係顯示與 工作件1保持在储機構21之狀位置之狀態之座標位置 的關係之說明圖。此外，第7(b)圖係顯示使保持機構21、亦 16 201043917 ρ工作件1從第7(a)圖所示之狀態旋轉9〇度而將第2切割道 4b作為加工對象的狀態。 然後，當檢測形成於保持在保持機構21之工作件丨之第 進行胃射加卫位置之校料，控制機構沿著如 此進行㈣献卫娜1之作為加工對象 之第1切割道4a， 執仃工作件表面尚度之檢測處理。即，使保持機構21移動， ΟΟ In the semiconductor reading process, a plurality of regions are divided into a plurality of regions in which the surface of the semiconductor workpiece having a substantially disk-shaped semiconductor workpiece is arranged in a lattice shape (the predetermined dividing line), and circuits such as Ic and LSI are formed in the divided regions. The semiconductor worker: the piece of the person cuts and cuts the 'and separates the circuits, and can manufacture the half: body piece. The cut by the cutting channel of the semiconductor work piece is usually performed by the weighing device. 'Also tried to illuminate the laser beam and the cutting method has been proposed. #, H+ D BaB1 and other guards are divided along the cutting path. Laser light; the wavelength of the external force and riding the hometown of the processing thief, and also try to use the work :). The beam is directed to the laser beam and the J1 method is applied to the laser beam of the pulsed laser which is divided into the wavelength of β. Using the ❿ ❿ 脉冲 雷 雷 雷 雷 雷 雷 雷 雷 雷 雷 雷 雷 雷 雷 - - - - - - - - - - - - - - - - - - - - - - - - - - - - 雷 雷In the modified layer having a penetrating scribe line, the workpiece is divided by applying an external force along the cut 201043917 cutting path which is formed by the continuous formation of the layer and the layer is reduced (for example, refer to Patent Document 2). However, the plate-like workpiece such as a wafer is bent, and the surface height of the workpiece is not fixed. Therefore, in any of the above processing methods, when the external force is applied, the workpiece can be divided into wafers with good quality, and the height position of the surface of the workpiece is detected. According to the detection result, the laser is corrected during laser processing. The focus position of the beam is formed, and the laser processing groove and the modified layer are uniformly formed. Therefore, a detecting device for detecting the height position of the surface of the workpiece using white light has been proposed (for example, refer to Patent Document 3). That is, by using the white light passing through the chromatic aberration lens to have a focal length which varies depending on the wavelength, the wavelength of the reflected light penetrating through the pinhole is defined to determine the focal length, and the surface height position of the workpiece is measured. PRIOR ART DOCUMENT PATENT DOCUMENT PATENT DOCUMENT PATENT DOCUMENT PATENT DOCUMENT PATENT DOCUMENT PATENT DOCUMENT PATENT DOCUMENT PATENT DOCUMENT PATENT DOCUMENT PATENT DOCUMENT LIST Patent Document No. 3,408, 805 Patent Document No. 3,408, 805 In these proposed examples, the height position of the surface of the workpiece can be measured accurately and accurately. However, the use of diffraction to disperse light according to wavelengths causes a phenomenon in which the spectra of adjacent orders overlap with each other, and therefore can be used only for detecting the wavelength of the free spectral region where no overlap occurs. That is, the wavelength band available for detection is limited. 201043917 The present invention has been made in view of the above, and it is an object of the invention to provide a height detecting device for detecting all wavelengths of a desired order of diffracted light by using a diffraction. Means for Solving the Problem In order to solve the above problems and achieve the object, the height detecting device of the present invention is a south detecting device that detects a height of a workpiece held by a holding mechanism, and is characterized in that it includes a white light source that emits white light, condenses each wavelength included in the white light, and forms a plurality of chromatic aberration lenses on the optical axis of the working member, and detects the chromatic aberration lens a height detecting mechanism that reflects the reflected light reflected by the working member after concentrating; the height detecting mechanism has a light that restricts passage of light other than the light that is connected to the focus near the surface of the workpiece in the light reflected by the surface of the workpiece a restriction mechanism, a diffractive optical element that diverges the reflected light that has passed through the light confinement mechanism into diffracted light that expands in the same plane, and a predetermined n-th order diffracted light (η-integer) included in the diffracted light and An n-th order diffracted light detecting mechanism that detects only the n-th order diffracted light in the different order diffracted light of different order of order n; the n-th order diffracted light detecting mechanism has a diffractive light collecting lens that condenses the diffracted light and the diffracted light of the aforementioned irregularly diffracted light, and the aforementioned n-th order diffracted light including the diffracted light collecting lens and the aforementioned irregular diffracted light a chromatic dispersion filter that refracts light in a direction out of the same plane from an angle different from each angle, and condenses the η-order diffracted light that is different from each wavelength by the chromatic dispersion filter, and the aforementioned irregular diffracted light a wavelength detecting sensor having only a detecting portion at a position where the n-th order diffracted light is concentrated, and detecting only a light intensity of each of the n-th order diffracted lights, and a memory lens having the chromatic aberration lens stored in 201043917 a memory for controlling a focus distance of each wavelength included in the white light; the height detecting device may determine the working member held by the holding mechanism according to the signal of the wavelength detecting sensor and the control map Height position. Advantageous Effects of Invention According to the present invention, it is possible to provide a mask detecting device which can use all wavelengths of a desired order of diffracted light when detecting a diffraction. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a perspective view showing the appearance of a main part of a laser processing apparatus equipped with a height detecting device according to an embodiment of the present invention. Fig. 2 is a perspective view showing a work piece for processing of the laser processing apparatus. Fig. 3 is a view schematically showing the configuration of a height detecting device of the present embodiment. Fig. 4 is a schematic view showing the situation of the condensed position. Fig. 5 is a structural view showing an enlarged portion A of Fig. 3; Fig. 6 is a structural view showing an enlarged view of a portion B in Fig. 3. Figs. 7(a) and 7(b) are explanatory views showing the relationship between the coordinate position and the state in which the workpiece is held at the predetermined position of the holding mechanism. C. Embodiment 3 Mode for Carrying Out the Invention Hereinafter, a height detecting device for carrying out the embodiment of the present invention will be described with reference to the drawings. In the present embodiment, a semiconductor crystal 201043917 in which a plurality of regions divided by a plurality of dicing streets arranged in a lattice shape are formed is shown as a detecting device, and the height position is detected along the cutting pair. The height is detected by the laser processing force, the second working piece is irradiated with the processing laser beam, and the second perspective view of the thunder laser processing device of the height detecting device of the present embodiment is shown, and the second figure is shown for The shot processing device 20 includes a solid circle of the workpiece. The mine holding device of the present embodiment assists in the operation of holding the pulsed w-beam beam 21a on the holding surface of the holding workpiece 1 The height detecting means for maintaining the height of the surface of the surface of the holding mechanism 21 while maintaining the holding operation of the holding mechanism 21, and the holding mechanism 21 attracts and keeps the work, and the tube portion _ In the first embodiment, as shown in Fig. 2, the workpiece 加工 is a top surface of the workpiece 砩, and is mounted on the ring frame, and is made of a synthetic resin sheet such as polyene. cut The work piece 1 is not particularly limited. For example, there are a wafer such as a semiconductor wafer, an adhesive member such as a DAE (Die Attach Film) which is mounted on the wafer for wafer mounting, or the like. Or a package of semi-conductive articles, ceramics, glass or lanthanide substrates, or even various processing materials requiring precision of the claw level. The workpiece of the present embodiment is formed on a semiconductor wafer and is formed on the surface la The plurality of first dicing streets 4a extending in the z-axis direction and the plurality of second dicing streets 4b extending in the z-axis direction are arranged in a plurality of rectangular regions, and the plurality of rectangular regions are formed in the plurality of rectangular regions. Further, the holding mechanism 21 is mounted on the slide blocks 25 and 26 of the two stages. The holding mechanism 21 is provided with a machining feed constituted by the ball screw 27, a nut (not shown), a pulse motor 28, and the like for the slide block 25. The mechanism 29 is moved in the X direction of the horizontal direction, and the mounted laser beam is irradiated to the laser beam irradiated by the processing laser beam irradiation mechanism 22. The holding mechanism 21 slides in the same direction. In the case where the ball screw 30 and the nut (the index feed mechanism 32 including the pulse motor 31 is not shown) moves in the horizontal direction of the gamma material, the workpiece 1 to be mounted is used for processing. The pulsed laser light irradiated by the laser beam irradiation unit 22 is indexed with respect to the indexing. Here, the machining feed mechanism 29 is provided with a machining feed amount detecting mechanism 33 for detecting the machining feed amount of the holding mechanism 21. The feed amount detecting mechanism 33 is disposed on the slide block 25 by a linear scale 33a disposed along the X-axis direction, and the read head not shown in the figure as the slide block 25 moves along the linear scale 33a. The processing feed amount detecting mechanism 33 sends a pulse signal of one pulse every 1 #m to a control mechanism not shown, the control mechanism counts the input pulse signal, and detects the machining feed of the holding mechanism 21. the amount. Similarly, the indexing feed mechanism 32 is provided with an indexing feed amount detecting mechanism 34 for detecting the indexing feed amount of the holding mechanism 21. The indexing feed amount detecting mechanism 34 is disposed on the sliding block 26 by a linear scale 3 4 & disposed along the γ-axis direction, and moves along the linear scale 34a along the sliding block 26 The composition of the read head is not shown. The indexing feed amount detecting means 34 sends a pulse signal of 1 pulse per lym to a control unit (not shown) which counts the input pulse signal and detects the indexing feed amount of the holding mechanism 21. Further, the processing laser beam irradiation mechanism 22 has a casing 35' which is substantially horizontally arranged with 201043917, and is provided with the casing 35 as an intermediary, and the support block 36 is provided with a Z-axis moving mechanism which can be illustrated in the figure. Move in the direction of the axis. The processing laser beam irradiation unit 22 includes a laser oscillation mechanism and a transmission optical system (not shown) disposed in the casing 35, and is disposed at the front end of the casing 35, and is oscillated by the laser beam oscillating mechanism. The pulsed laser beam for processing is applied to the concentrator 39 that is held by the workpiece 丨 of the holding mechanism 21. The laser beam oscillating mechanism is constituted by a laser oscillator composed of a YAG laser oscillator or a γν〇4 laser oscillator. A concentrating lens for processing a laser beam for processing the workpiece 1 to illuminate the processing beam is provided in the concentrator 39. Further, the concentrating lens for processing is provided with a lens actuator for a boring shaft that finely adjusts the focus in the x-axis direction at a high speed. Further, the height detecting device 1 attached to the front end portion of the casing 35 is used to illuminate the processing laser beam on the cutting path as the object to be processed of the workpiece 保持 held on the holding surface 21a of the holding mechanism 21. Before the mechanism 22, the detection light is irradiated first, and the surface height position on the scribe line is detected. The detection of the surface height is such that, even if the surface height of the workpiece i is changed, the condensing position of the beam is aligned with the height of the surface la, and a good laser processing groove can be formed. The information of the surface height position detected by the height detecting device 100 is sent to the control mechanism, and in the laser processing of the cutting track, the concentrator 39 for performing the laser beam for the workpiece m processing is provided. The control of the lens actuator for focusing the focus of the processing condenser lens is not shown in the drawing. Fig. 3 is a schematic view showing the structure of the height detecting device 1A of the present embodiment, Fig. 4 is a schematic view showing the state of the condensing position, and Fig. 5 is an enlarged view of the portion A of Fig. 3; The structure diagram shown, Fig. 6 is a block diagram showing the enlarged portion B of the ninth part of 2010. The height detecting device 100 of the present embodiment mainly includes a white light source 1A, a chromatic aberration lens 1〇2, and a height detecting mechanism 120. The white light source 101 is a light source that emits white light containing a plurality of wavelengths of light, and a tungsten filament lamp, a halogen lamp, a white LED or the like can be used. In the present embodiment, a li lamp is used. The chromatic aberration lens 102 is for illuminating the white light emitted from the white light source 101 toward the holding surface 21a (workpiece 1) side of the holding mechanism 21. Here, the chromatic aberration lens 102 is a condensing lens in which a plurality of focal points are formed on the optical axis of the workpiece 1 side with respect to each wavelength included in the white light. That is, since the refractive index of the white light collected by the chromatic aberration lens 102 differs depending on the wavelength, the focal length varies depending on the wavelength. As the chromatic aberration lens 102, an aspherical lens having an opening number ΝΑ = 0.68 and a viewing angle WD = 1 - 56 mm is used. Here, the collimator lens 105, the collecting lens 1〇6, the irradiation side optical fiber 107, and the collimator lens 1〇8 are disposed between the white light source 101 and the chromatic aberration lens 1〇2 in this order. The irradiation side optical fiber 107 forms the first optical path 109a, and the white light emitted from the white light source 1?1 is stably transmitted only by the white light required for the chromatic aberration lens 102. Further, the collimator lens 105 and the condensing lens 1 〇 6 are configured such that the white light emitted from the white light source 101 is collimated in parallel and then condensed to enter the incident end portion of the irradiation side optical fiber 1 〇 7 with good efficiency. A lens that affects chromatic aberration. Further, a fiber coupler 110 integrated with the incident end side of the optical fiber 121 is provided on the emission end side of the irradiation-side optical fiber 107, and is coupled to the common optical fiber. The collimating lens 1〇8 disposed between the common optical fiber 111 and the chromatic aberration lens 1〇2 suppresses the parallel transmission of white light emitted from the common optical fiber 111 via the irradiation side optical fiber 1〇7, and guides it. Effect of chromatic aberration on the chromatic aberration lens 1〇2 201043917 Lens. Further, the degree detecting means 120 detects the surface height position of the workpiece 依据 based on the reflected light of the white light reflected by the chromatic aberration lens 1 〇 2 and reflected by the surface of the workpiece 1. This height detecting mechanism mainly has an optical fiber 12 diffractive optical element 122 and a pupil-order diffracted light detecting mechanism 130. The optical fiber 121 forms a second optical path l〇9b different from the first optical path 109a, and is used to limit light other than the light that is connected to the focus near the surface of the workpiece in the reflected light of the white light reflected by the surface of the workpiece 1. The light passing through the restriction mechanism. Here, the restriction refers not only to the case where the light does not pass at all, but also to the case where a part does not pass. The optical fibers 107, 111, and 121 are composed of a core and a shell, and for example, a multimode fiber having a core diameter of 5 〇 #m is used. Further, the diffractive optical element 122 is a diffractive grating for converting the detection diffracted light corresponding to the wavelength component of the reflected light passing through the optical fiber 121. Therefore, the diffractive optical element 122 of the present embodiment spreads the reflected light parallelized by the collimator lens 123 at the exit end of the optical fiber 121 by the optical fiber ΐ2 to the second optical path l〇9b, and is dispersed in the same plane, for example, the γζ plane. The diffracted light is expanded inside. Further, the collimator lens 123 is also a lens that suppresses the influence of chromatic aberration. Further, the first-order diffracted light detecting means 130 is for detecting only 1 Ps of diffracted light in the high-order diffracted light such as the first-order diffracted light and the second-order diffracted light included in the diffracted light diverging from the optical element 122. The mechanism is set to an n-th order diffracted light detecting mechanism. The first-order diffracted light detecting means 130 mainly includes a diffractive light collecting lens 131, a dispersion filter 132, a wavelength detecting sensor 133, a memory 134, and a surface height position calculating unit 135. The diffractive light collecting lens 131 is configured to cause the diffracted light including the first-order diffracted light (n-th order diffracted light) and the high-order diffracted light (appropriate diffracted light) diverging from the diffractive optical element 122 201043917 toward the wavelength detection sensing H 133 spotlights. Further, the chromatic dispersion filter 132 is configured to refract the diffracted light including the 丨-order diffracted light and the high-order diffracted condensed light condensed by the diffracted condensing lens 131 at an angle different from each wavelength, so that the diffracted light is diffracted The optical element 122 has an optical element extending outward in the plane of the divergence (the same plane), that is, the X-axis direction, and can be made of a prism or the like. Further, the wavelength detecting sensor 133 has a detecting portion where the dispersion filter 132 collects light in the first-order diffracted light and the high-order diffracted light which are different in the respective wavelengths, and only the pupil-order diffracted light is concentrated. Only the light intensity of each wavelength of the first-order diffracted light is detected. That is, the wavelength detecting sensor 133 is diffracted by the diffractive optical element 122 and is incident on the diffracted light at a position different from the wavelength by the diffractive collecting lens 131 so that the detecting portion receives only the first-order diffracted light, and the detecting portion detects Light intensity at each wavelength. The wavelength detecting sensor 133 can use a CCD line type sensor, a CMOS sensor, or the like that can detect the wavelength of the diffracted light that is condensed by the condensing lens 131. Here, the case where the diffracting position of the diffracted light condensed by the wavelength detecting sensor 133 via the diffractive optical element 122, the diffractive collecting lens 131, and the dispersing filter 132 is described with reference to Fig. 4 . For example, when the first-order diffracted light based on white light is to use a wavelength region of 400 to 100 nm, each wavelength of light 400, 500, 600 of the first-order diffracted light passing through the diffractive optical element 122 and the diffractive collecting lens 131 is used. 700, 800, 900, lOOOnm As shown in Fig. 3, the divergence is formed by expanding the position corresponding to the wavelength in the same plane (YZ plane). At this time, one of the spectra of the second-order diffracted light which is the adjacent order light as the high-order diffracted light partially overlaps the long-wavelength side spectrum of the first-order diffracted light. Specifically, the wavelength light 400 and 500 nm of the second-order diffracted light 12 201043917 passing through the diffractive optical element 122 and the diffractive condensing lens 131 are condensed in the same plane (YZ plane) to almost overlap the first-order winding. The position of 800, lOOOnm of the light. As a result, it is impossible to distinguish the difference between the first-order diffracted light 800 nm and the second-order diffracted light 400 nm, the first-order diffracted light 100 Onm, and the second-order diffracted light 500 nm in the wavelength detecting sensor 133, and the first-order diffracted light at a wavelength of 700 nm or less. Spectral area usage is limited. Therefore, in the present embodiment, the dispersion filter 132 is added so that the first-order diffracted light and the second-order diffracted light are refracted at an angle different from each wavelength to a direction other than the γ-ζ plane (the same plane) where the diffracted light 122 is diverged. On the other hand, as shown in Fig. 4, there is a two-dimensional extension in the X-axis direction, and discrimination between the first-order diffracted light and the second-order diffracted light can be performed. The detecting portion 133a of the wavelength detecting sensor 133 is disposed to be wound only in the first order in the first-order diffracted light and the second-order diffracted light (high-order diffracted light) which are collected by the dispersive filter 132 at the difference of the respective wavelengths. The location where the light is concentrated is sensitive. Thereby, in the region where the detecting portion 133a does not have the first-order diffracted light and the second-order diffracted light, the first-order diffracted light can be used in the entire wavelength region of 400 to l〇〇〇nm. Further, the 'surface height position calculating unit 135' controls the storage of the focal length of each wavelength of light contained in the white light collected by the chromatic aberration lens 102 and the surface height of the workpiece j to be stored in the memory 丨3 4 . In the figure, based on the detection result of the wavelength detecting sensor 133, the surface height position of the workpiece w is calculated, and the height position information is obtained. Further, the control map stored in the memory 134 is set to the focal length of each wavelength, and the relationship between the z-axis height (the height position of the surface la of the workpiece 1) and the peak detection wavelength detected by the wavelength detecting sensor 丨 333 is measured in advance. And the winner. Next, the principle of detecting the height position of the surface la of the workpiece 1 in the present state will be described. The white light emitted from the white light source 101 is output from the fiber end by the optical fibers 1〇7, 13 201043917 m, and after the collimating lens 108 forms a parallel beam, passes through the chromatic aberration lens 102, and collects light on the surface 1a of the workpiece 1. . The white light reflected by the surface 13 is retrograde in the optical path. At this time, the light focused on the surface ia of the workpiece 仅为 is only a specific wavelength of light. Therefore, in the white light, the light of the continuous focus on the surface can be most strongly combined with the small-diameter core of the common optical fiber m (optical fiber 121), and the light of other wavelengths is no longer combined with the common money lu (the optical fiber is called the core) Thereby, the light which is combined with the focused wavelength of the core of the common optical fiber m (optical fiber 121) is guided to the side of the diffractive optical element 122 in the detecting mechanism 12 by the optical fiber 121 with good efficiency. Then, The diffractive optical element 122 branches into a φ (four)-like ray at a pre-turn YZ. The diffracted diffracted condensing condensing lens 131 converges at a wavelength detecting angle 感 33 at an angle corresponding to the wavelength. The diffracted light condensed by the diffractive condensing lens 131 includes the second-order diffracted light in addition to the diffracted diffracted light, and the i-order diffracted light and the second-order diffracted light vary with wavelength by the dispersion filter. The angle is refracted in the direction of the x-axis outside the plane relative to the predetermined YZ plane. Then, only "the diffracted light is received by the wavelength detecting device 133. This wavelength detecting sensor 133 measures the received The light of the light (1st order diffracted light) is long, and the measurement wavelength is The value can be detected on the surface of the workpiece laLa to focus the wavelength of the light. Therefore, the surface height position calculating unit 135 obtains the peak wavelength information from the wavelength detecting sensor 133 as a detection result, and refers to the memory 134. The control chart 'calculates the height position of the surface of the current workpiece '' to obtain the height position information. Here, since the wavelength detection sensing using the spectroscope is as follows, the peak can be obtained at a high speed of a sampling rate of 1 kHz or more. 201043917 Value wavelength information, so for example, when the workpiece 1 is moved at a speed of 6〇〇111111/3, the surface 13 of the workpiece 1 can be measured at intervals of 〇6 mm on each of the scribe lines SI and S2. In the present embodiment, since the chromatic aberration lens 102 condenses the white light and illuminates toward the holding surface 21a side, even if the height of the surface la of the workpiece 有 is deviated compared to the case where the single-wavelength light is used, The peak power of the focus must be returned, so the height position of the surface la can be detected with high precision. This point is further described in detail with reference to Fig. 5. As mentioned above, from the white light source 101 The white light emitted by the chromatic aberration lens 1〇2 is directed toward the workpiece 1 held on the holding surface 21a of the holding mechanism 21. At this time, the white light passed by the chromatic aberration lens 1〇2 has a focus depending on the wavelength. That is, the chromatic aberration lens 102 forms a plurality of focal points on the optical axis of each of the wavelengths included in the white light. Therefore, as shown in FIG. 5, at the optical axis center of the chromatic aberration lens 102. The range L immediately below has a myriad focus on each wavelength contained in the white light. Therefore, in order to cause the surface la of the workpiece 1 to exist in the range L in which the innumerable focus exists, the surface of the workpiece 1 is not irradiated when the white light is irradiated. The deviation of the height position of la 'reflected light after focusing must exist' can reliably detect the height position of the surface la of the workpiece 1. Further, the range L of the deviation of the display focus can be freely designed from the number /zm to several mm depending on the number of apertures NA of the chromatic aberration lens 102, the material, or the use of the diffractive lens as the chromatic aberration lens 102 or the like. Further, the light reflected by the surface la of the work piece 1 is retrograde in the optical path and incident on the common optical fiber 11U optical fiber 121). At this time, since the light reflected by the unfocused holding surface 21a 15 201043917 is not easily coupled to the common optical fiber 111, the amount of incident light is small, and the light intensity detected by the wavelength detecting sensor 133 is reduced. On the other hand, in the white light, 'the light of the wavelength near the surface la is not in focus due to the deviation of the height position of the surface la of the workpiece 1, as shown in Fig. 6, 'the strongest recombination is the common fiber. The core 111a surrounded by the 11 lb shell of 111. Thereby, the intensity of the light detected by the wavelength detection sensing benefit 13 3 is increased after the common optical fiber 111 (optical fiber 121) is guided to the second optical path 109b. According to the present embodiment, the white light reflected by the surface 13 of the workpiece 引导 is guided to the wavelength detecting sensor 133 side by being guided by the common optical fiber 1U (optical fiber 121) having a core diameter of 50 "!:! The spatial filter has high precision and high degree of freedom in configuration. Next, the operation of the laser processing apparatus 20 including the above-described height detecting device 100 will be described. The workpiece member is placed on the holding surface 21a of the holding mechanism 21 to be sucked and held. Then, the holding mechanism 21 that sucks and holds the work piece 1 is positioned directly below the photographing mechanism not shown, and the calibration work for detecting the processing area of the workpiece i to be subjected to the laser processing is performed. That is, the second cutting path for performing the predetermined direction of the shape workpiece 丨 is performed, such as the miscellaneous pattern of the processing concentrating lens not shown in the condensing n39 along the first scribe line 4a. (4) Image processing, (4) Line calibration. The same applies to the second cutting path 4b. When this is done, when the calibration is performed, the workpiece 1 on the holding mechanism 21 is positioned in the state of the coordinate as shown in Fig. 7(4). Fig. 7 is an explanatory view showing the relationship between the coordinate position and the state in which the workpiece 1 is held at the position of the reservoir 21. Further, Fig. 7(b) shows a state in which the holding mechanism 21 and the 201043917 ρ workpiece 1 are rotated by 9 degrees from the state shown in Fig. 7(a), and the second cutting lane 4b is processed. Then, when detecting the correction material formed in the stomach-lifting position of the workpiece held by the holding mechanism 21, the control mechanism proceeds along with the first cutting lane 4a which is the object of processing (4)检测 Detecting the surface finish of the workpiece. That is, the holding mechanism 21 is moved, Ο
將第7(a)圖中最下位之第刀割道4a定位於色像差透鏡 102之正下方。因此’可使高度檢測裝置剛作動，同時， 使保持機構21配合預定之加卫進給速度於加工進給方向移 動。藉此處理’可就最下位之第丨切割道4a，依序檢測最下 位之第1切割道4a上之各部之表面1&的高度位置。所檢測出 之表面尚度之貢訊係與各檢測時間點之X、γ座標賦與關聯 性’而暫時儲存於圖中未示之記憶體。 此外，表面la之高度位置係根據波長檢測感測器133之 取樣率’依序取得者，如前述當取樣率為丨藤，工作件】 以6〇〇mm/s之速度移動時，在切割道乜上可以〇 間隔 依序檢測工作件1之表面la之高度。 田關於最下位之第1切割道4a之檢測處理結束時，控制 機構使保持機構21移動，而使第7⑷圖中最下位之第1切割 道4a定位於加οι用集光透鏡之正下方。此時，色像差透鏡 102設定成定位於先行之下個第1切割道如之正下方。然 後，控制機構同時執行對最下位之第丨切割道4a之雷射加工 處理與對先行之下個切割道如之工作件表面高度的檢 測處理。 17 201043917 。即’使保持機構21配合預定加卫進給速度於加工進給 Ί此處理中’㈣機構2G參照與儲存於記憶體 加工動作之第1切割道灿關之表面高度的資訊，控制雷射 時間:先為=用聚光透鏡到達光束照射開始位置Μ之 射軸驅動、，而Γ對 1!^光束’藉使加工用雷射光束照 始。 ，工乍件1之加工用雷射光束之照射開 二 面藉依據工作件1之表面高度資訊，控制圖中 透鏡照射轴用透鏡致動器，調整高度位置’使從加工用聚光 …—之加工用雷射光束之聚光點與I作件1之表面la 道铜 工作件1之表面Μ著最下位之第1切割 鏡照射之加：雷冓:：加工。結果’從加，光透 雷射光束之聚光點對準工作件1之表面 透鏡4職光束照射結束位細_ 工用雷射光束二:Γ光束照射機構3之驅動停止，停止加 之照射停止。而可使h作件1之加工用雷射光束 使高度制裝置則與_加工動作並行 而:動：下個先行之第i切割道4a，依序檢測第i切割道 資a:r面1a的高度位置。所檢測出之表面高度之 杨=時間點™職與關聯性’而暫時储 18 201043917 之後’對此後之^切割道4a，同樣地令此種雷射加工 • 處理與高度檢㈣理為並行處理而反覆執 仃；，、、:後*執仃對所有第1切割道4 a之雷射加工處理與高 度檢測裝置觸之檢測處理後，使保持機構21旋獅度，定 位於第7⑻圖所示之狀態，對第2切割道仙全體亦同樣地， 執行雷射加工處理及高度檢測裝置1〇〇之檢測處理。當所有 處理、束時保持有工作件1之保持機構^返回最初吸引保 〇 j了工作件1之位置’在此，解除工作件1之吸引保持。接 著，工作件1以圖中未示之搬送機構搬送至分割程序。 本心明不限於上述實施形態，只要為不脫離本發明之 曰趣之範11彳進行各種變形。舉例言之在上述實施开） 態中，以將繞射光所含之1階繞射光作為為檢測對象之預定 階數繞射光之1階繞射光檢測機構i3 〇作為η階繞射光檢測 機構的例而說明，預定階數繞射光不限於1階繞射光。要點 係只要為可在繞射光所含之預定η階繞射光(η係整數)及與 〇 Θnh &數不同之異階繞射光中僅檢測η階繞射光之ηρ皆繞 射光檢測機構即可，亦可令其他階數繞射光為預定繞射 光’再者’作為檢測對象之繞射光亦可不為低階而為高階。 又’舉例言之，在上述實施形態中 ’以藉照射為工作 件1吸收之波長之加工用雷射光束，而形成雷射加工溝之雷 射加工例而說明，而藉照射穿透工作件1之波長之加工用雷 射光束，形成改質層時，亦同樣地適用，而不管表面1&之 變動，皆可從表面la於一定之深度位置形成改質層。 又’在上述實施形態中，以使用切割膠帶3之工作件1 201043917 之例而說明，即使為不使用切割膠帶3，而使工作件1直接 保持在保持機構21之保持面21a上之類型者亦同樣地適用。 【圖式簡單說明】 第1圖係顯示裝備有本發明實施形態之高度檢測裝置 之雷射加工裝置之主要部份的外觀立體圖。 第2圖係顯示用於該雷射加工裝置之加工之工作件的 立體圖。 第3圖係概略地顯示本實施形態之高度檢測裝置之結 構圖。 第4圖係顯示聚光位置之情形之模式圖。 第5圖係將第3圖中之A部份放大而顯示的結構圖。 第6圖係將第3圖中之B部份放大而顯示的結構圖。 第7(a)圖、第7(b)圖係顯示與工作件保持在保持機構之 預定位置之狀態之座標位置的關係之說明圖。 【主要元件符號說明】 1.. .工作件 la.··表面 2.. .環狀框架 3.. .切割膠帶 4a...第1切割道 4b...第2切割道 5.. .器件 20.. .雷射加工裝置 21.. .保持機構 2 la...保持面 22.. .加工用雷射光束照射機構 24.. .圓筒部 25,26…滑動塊 27.30.. .滾珠螺桿 28β1...脈衝馬達 29.. .加工進給機構 32.. .分度進給機構 3 3...加工進給量檢測機構 20 201043917 33a，34a...線性標度 ' 34...分度進給量檢測機構 、 35...殼體 36.··支撐塊 39.. .聚光器 100.. .高度檢測裝置 101.. .白光源 102.. .色像差透鏡 〇 1G5...準直透鏡 106.. .聚光透鏡 107…照射側光纖 108.. .準直透鏡 - 109a....第 1 光程 - 10%..·第2光程 110…光纖耦合器 111.. .共通光纖 Ο 11 la...纖核 111b...纖殼 120.. .南度檢測機構 121.. .光纖 122.. .繞射光學元件 123.. .準直透鏡 130.. .1.繞射光檢測機構 131.. .繞射光聚光透鏡 132.. .色散濾波器 133.. .波長檢測感測器 133a...檢測部 134.. .記憶體 135.. .表面高度位置運算部 Α,Β...部份 Α1...光束照射開始位置 Β1...光束照射結束位置 51.52.. .切割道 21The lowermost cutting path 4a in the seventh drawing (a) is positioned directly below the chromatic aberration lens 102. Therefore, the height detecting means can be actuated, and at the same time, the holding mechanism 21 is moved in the machining feed direction in cooperation with the predetermined urging feed speed. By this, it is possible to sequentially detect the height position of the surface 1& of each of the lowermost first cutting lanes 4a in the lowermost third cutting lane 4a. The sensed surface of the detected surface is associated with the X and γ coordinates of each detection time point and temporarily stored in a memory not shown. In addition, the height position of the surface la is sequentially obtained according to the sampling rate of the wavelength detecting sensor 133, as described above, when the sampling rate is 丨藤, the workpiece is moved at a speed of 6〇〇mm/s, and is cut. The height of the surface la of the workpiece 1 can be sequentially detected at intervals on the switch. When the detection processing of the lowermost first cutting lane 4a is completed, the control mechanism moves the holding mechanism 21, and the lowermost first cutting lane 4a in the seventh figure (4) is positioned directly below the addition collecting lens. At this time, the chromatic aberration lens 102 is set to be positioned just below the first lower cutting path. Then, the control mechanism simultaneously performs a laser processing process for the lowermost third cutting track 4a and a detection process for the surface height of the preceding lower cutting path such as the workpiece. 17 201043917. That is, 'the holding mechanism 21 is engaged with the predetermined feeding speed in the processing feed Ί in this process' (4) The mechanism 2G refers to the information on the surface height of the first scribe line stored in the memory processing operation, and controls the laser time. : First, use the condenser lens to reach the beam drive start position Μ of the axis drive, and Γ pair 1!^ beam' by the processing laser beam. According to the surface height information of the workpiece 1 in the processing of the laser beam, the lens is irradiated with the lens actuator in the control chart, and the height position is adjusted to make the light from the processing... The spot of the laser beam for processing and the surface of the I-piece 1 are la-plated. The surface of the copper work piece 1 is irradiated with the first lower-cut mirror: Thunder:: Processing. The result 'from the plus, the light-converging point of the light-transmitting laser beam is aligned with the surface lens of the workpiece 1 and the end of the beam is irradiated. _ The laser beam for the work beam 2: The driving of the beam irradiation mechanism 3 is stopped, and the stop is stopped. . The processing laser beam for processing the workpiece 1 can be made in parallel with the processing operation of the height device: moving: the next i-th cutting channel 4a, sequentially detecting the i-th cutting channel a: r surface 1a Height position. The detected surface height of Yang = time point TM job and relevance 'and temporarily stored 18 201043917 'after this ^ cutting road 4a, the same laser processing, processing and height inspection (four) for parallel processing Repeatedly;;,:: After the execution of the laser processing of all the first cutting lanes and the detection of the height detecting device, the holding mechanism 21 is rotated to the lion degree and positioned in the 7th (8) In the same manner as in the second cutting path, the laser processing and the detection processing of the height detecting device 1 are performed in the same manner. When all the processes and bundles are held, the holding mechanism of the work piece 1 returns to the position where the work piece 1 is initially attracted. Here, the attraction holding of the work piece 1 is released. Next, the work piece 1 is transported to the splitting program by a transport mechanism not shown. The present invention is not limited to the above embodiments, and various modifications can be made without departing from the scope of the invention. For example, in the above-described embodiment, the first-order diffracted light detecting means i3 for diffracting the first-order diffracted light included in the diffracted light is used as an example of the n-th order diffracted light detecting means. It is to be noted that the predetermined order diffracted light is not limited to the first order diffracted light. The point is that the ηρ which can detect only the n-th order diffracted light in the predetermined n-th order diffracted light (η-integer) and the different 〇Θnh & Alternatively, the diffracted light whose other order diffracted light is a predetermined diffracted light 'again' as the detection target may not be a low order but a high order. Further, as an example, in the above-described embodiment, a laser beam for processing which is a wavelength absorbed by the workpiece 1 by irradiation is formed, and a laser processing method for forming a laser processing groove is described. The laser beam for processing at a wavelength of 1 is similarly applied when forming a modified layer, and the modified layer can be formed from a surface at a certain depth position regardless of the surface 1& Further, in the above-described embodiment, the case of using the work piece 1 201043917 of the dicing tape 3 is described as the type in which the work piece 1 is directly held on the holding surface 21a of the holding mechanism 21 without using the dicing tape 3. The same applies. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a perspective view showing the appearance of a main part of a laser processing apparatus equipped with a height detecting device according to an embodiment of the present invention. Fig. 2 is a perspective view showing a work piece for processing of the laser processing apparatus. Fig. 3 is a view schematically showing the configuration of a height detecting device of the present embodiment. Fig. 4 is a schematic view showing the situation of the condensed position. Fig. 5 is a structural view showing an enlarged portion A of Fig. 3; Fig. 6 is a structural view showing an enlarged view of a portion B in Fig. 3. Figs. 7(a) and 7(b) are explanatory views showing the relationship between the coordinate position and the state in which the workpiece is held at the predetermined position of the holding mechanism. [Description of main component symbols] 1.. Workpiece la.·. Surface 2.. Annular frame 3.. Cutting tape 4a... First cutting pass 4b... Second cutting pass 5.. Device 20: laser processing device 21.. holding mechanism 2 la... holding surface 22: processing laser beam irradiation mechanism 24. cylindrical portion 25, 26... sliding block 27.30.. Ball screw 28β1...pulse motor 29.. machining feed mechanism 32.. indexing feed mechanism 3 3... machining feed amount detecting mechanism 20 201043917 33a, 34a... linear scale '34. .. indexing feed amount detecting mechanism, 35... housing 36.··support block 39.. concentrator 100.. height detecting device 101.. white light source 102.. chromatic aberration lens 〇1G5...collimating lens 106.. concentrating lens 107...ilishing side optical fiber 108..collimating lens - 109a....first optical path - 10%..·2nd optical path 110...fiber Coupler 111.. Common optical fiber la 11 la... nucleus 111b... hull 120.. Southern detection mechanism 121.. Optical fiber 122.. Diffractive optical element 123.. Collimating lens 130..1. Diffractive light detecting mechanism 131.. Diffractive light collecting lens 132.. Dispersion filter 133.. Wavelength detecting sensor 133a ...detection unit 134.. memory 135.. surface height position calculation unit Α, Β ... part Α 1 ... beam irradiation start position Β 1 ... beam irradiation end position 51.52.. twenty one