201136692 六、發明說明： 【發明所屬之技術領域】 [0001] 本發明係一種將雷射光分為兩道切割光束，以提高晶圓 切割加工效率之分光系統，此二光束之強度與間距皆可 調整以滿足各種切割需求。 [先前技術] [0002] 目前LED業界在晶粒製造上主要有下列幾項趨勢：1.晶粒 尺寸縮小，2.切割道尺寸縮小，3.薄晶圓化，4.異質材 料接合，5.高硬度基板之使用等發展方向。這些發展趨 勢都對傳統以機械切割的方式（例如Dicing Saw， Diamond Scribe，Diamond Saw等切割技術）不管在產 出速度或良率上都造成極大挑戰；反觀利用雷射切割的 技術，則不管是採用直接切斷或劃線裂片的製程皆可有 效的改善機械切割所遭遇的問題。 [0003] 以切割晶圓為例，傳統雷射切割的技術皆是利用一雷射 光源產生一道雷射光，並以一光學聚焦元件將雷射光聚 成一光點，然後將此光點沿著晶圓上的切割道將其逐一 劃過。 [0004] 但在晶粒尺寸越來越小的情況下，晶圓上切割道的數目 及其總路徑長度相對增加許多，因此必須不斷提高雷射 光點的移動速度來縮短切割時間。 [0005] 中華民國專利1304758雖對此問題提出解決方案，但其所 提及的繞射光學元件，全像光學元件或鍍膜分光鏡雖可 分出數道光束，但是只有每一個光學元件均製作地完全 合乎規格的條件下，否則每道光束的強度必定會有所差 099113645 表單編號 A0101 第 4 頁/共 14 頁 0992024049-0 201136692 Ο [0006] ❾ [0007] 異，於是會造成每道光束的切割痕深淺不一，因此此項 發明只是在理論上可行，在現實面零件製造必定會有一 個公差範圍，雖然製造過程中每個合格零件的規格都會 在公差範圍内，但是不能保證每一個公差的值都是相同 的，這些差異就會造成雷射強度不同，強度不同割出的 深度就有差異，該發明並有沒有對每一子光束設計調整 強度的機構，切割的深度不同裂片的時候就會發生裂片 不均，或是有的片不易斷裂，因此實用性似乎不高，此 外該發明所設計的光束間距離調整機構只可將光點間之 距離拉大，但若需切割較兩光點原始距離為小的晶粒， 此調整機構無法達成。 【發明内容】 有鑒於前述習知的切割方式及中華民國專利1304758之缺 點，本發明之主要的目的係提供一種兩道子光束切割距 離可以自由調整、功率可以單獨調校至完全相同之雷射 分光系統，將一道雷射光分為兩道，同時進行切割的工 作，可減少LED晶圓切割時間。 為達成前述主要目的，本發明之雷射分光系統主要包含 有：一雷射源，由其產生一母光束；在雷射源後置一半 波片，旋轉此波片可調整由母光束分出之S與P子光束的 強度；一極化分光元件（PBS)，係設置於半波片後之母光 束的路徑上，可將母光束分為S與P兩道子光束；一反射 鏡，係設置於S子光束之行進路徑上，可藉由調整此反射 鏡的兩個象限角度來改變S子光束的聚焦位置，這樣可以 調整S與P光束的距離，也就是切割的距離；於S與P子光 099113645 表單編號A0101 第5頁/共14頁 0992024049-0 201136692 文s jp路徑上各設置一片偏光片，此偏光片可各別再 做S與P兩道子光束精細的強度調整；其後於s與p兩道子 光束之订進路經上再裝置一聚焦元件，此聚焦元件可 將兩子光束聚焦成可進行切割之兩個光點，^聚焦在同 待切割晶圓表面，如此便可於晶圓上同時進行兩道切 割的加工’因光束的強度可經偏光片調成―致因而不 會有切割深度不同的困擾。 【實施方式】 [0008] 099113645 請參閱第一圖，本發明實施例所示之雷射晶圓切割分光 系統係包含有：一雷射光源丨，產生母光束20;母光束20 經過一濾波器2過濾不需要之光源；母光束2〇再經過一半 波片3，旋轉此半波片3可調整母光束2〇的偏振方向此 調整可以調整後面經極化分光元件（PBS)5分出的子光束s 21與P 22的強度’ 一光束擴大器（Beam Expander)4可 以減小光束聚焦後之光點；一極化分光元件（pBS)5，將 母光束20分為兩道子光束S 22 ; —反射鏡組6， 裝置在子光束S 21的路徑上，係用來調整子光束s 21投 射在加工件表面之位置；兩片偏光片7，分別置於子光束 3 21與p 22的行進路徑上以對各子光束強度做更精細的 調節’如此才可使兩子光束的切割痕有相同的深度；— 聚焦組8,係置於精細調節過後的子光束3 21與P 22的 仃進路徑上，可將之子光束s 21與p 22聚焦在同一待切 ^之晶圓9表面並形成足以進行切割之兩光點。 明參閱第二圖，晶圓9表面需加工許多道綜橫交錯的切割 道12 ’雷射子光束S 21與ρ 22經妥善的對準晶圓9上平 行的兩條切割道12後’雷射子光束s 21與Ρ 22便可同時 表單蝙號· Α0101 第6頁/共14頁 η 201136692 切割兩條切割道12。 °月參考第二a、三b圖，所使用的聚焦鏡8可為一複合鏡 (Doublet 〇r Tripiet)8a ;亦或顯微鏡式聚焦鏡 (Qbjective lens)8b ;亦或其他任何光學元件，其有 足夠之孔彳至光摘（Aperture Stop)使得分光後之子光束 S 21與P 22能全部進入，並能在同一聚焦平面形成兩個 聚焦、光點’聚焦鏡8之目的在將雷射光束聚焦成一為小光 點’以提高其功率密度以利切割。201136692 VI. Description of the Invention: [Technical Field] [0001] The present invention is a spectroscopic system that splits laser light into two cutting beams to improve the efficiency of wafer cutting processing, and the intensity and spacing of the two beams can be Adjust to meet a variety of cutting needs. [Prior Art] [0002] At present, the LED industry mainly has the following trends in die manufacturing: 1. Grain size reduction, 2. Cutting channel size reduction, 3. Thin waferization, 4. Heterogeneous material bonding, 5 The development direction of the use of high hardness substrates. These trends are very challenging for traditional mechanical cutting methods (such as Dicing Saw, Diamond Scribe, Diamond Saw, etc.), regardless of the speed of output or yield; in contrast, the technology of using laser cutting, whether it is The process of directly cutting or scribing the lobes can effectively improve the problems encountered in mechanical cutting. [0003] Taking a diced wafer as an example, the conventional laser cutting technique uses a laser light source to generate a laser light, and an optical focusing component is used to concentrate the laser light into a light spot, and then the light spot is along the crystal. The cutting path on the circle passes them one by one. [0004] However, in the case where the grain size is getting smaller and smaller, the number of scribe lines on the wafer and the total path length thereof are relatively increased, so it is necessary to continuously increase the moving speed of the laser spot to shorten the cutting time. [0005] Although the Republic of China Patent 1304758 proposes a solution to this problem, the diffractive optical element, the holographic optical element or the coated beam splitter may be divided into several beams, but only each optical element is fabricated. The ground is completely in accordance with the specifications, otherwise the intensity of each beam will definitely be different. 099113645 Form No. A0101 Page 4 of 14 0992024049-0 201136692 Ο [0006] ❾ [0007] Different, so each beam will be caused The cutting marks are different in depth, so the invention is only theoretically feasible. There must be a tolerance range in the manufacture of the actual surface parts. Although the specifications of each qualified part in the manufacturing process are within the tolerance range, there is no guarantee for each one. The values of the tolerances are the same. These differences will result in different laser intensities, and the depths of the different cuts will be different. The invention also has a mechanism for adjusting the strength of each sub-beam, and the cutting depth is different. When the lobes are uneven, or some of the pieces are not easily broken, the practicality does not seem to be high, and the invention is designed. The distance between the beam adjustment mechanism only the distance between the points of light widened, but cutting For two spot than the original distance of small grain, this adjustment mechanism can not be reached. SUMMARY OF THE INVENTION In view of the above-described conventional cutting method and the disadvantages of the Republic of China patent 1304758, the main object of the present invention is to provide a two-beam sub-beam cutting distance that can be freely adjusted, and the power can be individually adjusted to the exact same laser beam splitting. The system divides a laser beam into two passes and performs cutting at the same time to reduce the LED wafer cutting time. In order to achieve the foregoing main object, the laser beam splitting system of the present invention mainly comprises: a laser source, which generates a mother beam; a half wave plate is disposed behind the laser source, and the wave plate is rotated to adjust the separation by the mother beam. The intensity of the S and P sub-beams; a polarization splitting element (PBS) is placed on the path of the mother beam behind the half-wave plate to divide the mother beam into two sub-beams of S and P; a mirror Set on the travel path of the S sub-beam, the focus position of the S sub-beam can be changed by adjusting the two quadrant angles of the mirror, so that the distance between the S and P beams, that is, the distance of the cut, can be adjusted; P子光099113645 Form No. A0101 Page 5 of 14 0992024049-0 201136692 Text s jp path each set a polarizer, this polarizer can do the S and P two sub-beams fine intensity adjustment; A focusing component is further disposed on the s and p sub-beams, and the focusing component can focus the two sub-beams into two spots that can be cut, and focus on the surface of the wafer to be cut. Simultaneously perform two cuts on the wafer Cutting processing 'Because the intensity of the beam can be adjusted by the polarizer, there is no trouble with different cutting depths. [0008] [0008] 099113645 Please refer to the first figure, the laser wafer cutting and splitting system shown in the embodiment of the present invention includes: a laser source 丨, generating a mother beam 20; the mother beam 20 passes through a filter 2 filtering the unwanted light source; the mother beam 2〇 passes through half of the wave plate 3, and the half wave plate 3 is rotated to adjust the polarization direction of the mother beam 2〇. This adjustment can be adjusted by the latter polarized beam splitting element (PBS) 5 The intensity of the sub-beams s 21 and P 22 'a Beam Expander 4 can reduce the spot after the beam is focused; a polarization beam splitting element (pBS) 5 splits the parent beam 20 into two sub-beams S 22 - a mirror group 6, the device is arranged on the path of the sub-beam S 21 for adjusting the position of the sub-beam s 21 projected on the surface of the workpiece; two polarizers 7 are placed in the sub-beams 3 21 and p 22 respectively A finer adjustment of the intensity of each sub-beam is made on the path of travel 'so that the cut marks of the two sub-beams have the same depth; — the focus group 8 is placed in the finely adjusted sub-beams 3 21 and P 22 On the path of the intrusion, the sub-beams s 21 and p 22 can be focused on A surface of the wafer to be cut 9 ^ of cutting and forming two light spots sufficient to perform. Referring to the second figure, the surface of the wafer 9 needs to be processed by a plurality of cross-cutting dicing streets 12' The laser beam S 21 and ρ 22 are properly aligned with the two parallel dicing streets 12 on the wafer 9 after the thunder The beam s 21 and Ρ 22 can be simultaneously formed in the form of a bat number Α 0101 Page 6 / 14 pages η 201136692 Cutting two cutting lanes 12 . Referring to the second a and third b diagrams, the focusing mirror 8 used may be a composite mirror (Doublet Tripr Tripiet) 8a; or a Qbjective lens 8b; or any other optical component. There is enough aperture stop to make the sub-beams S 21 and P 22 can be fully entered, and can form two focusing and spotting points on the same focal plane. The focusing mirror 8 is used for the laser beam. Focus on a small spot to increase its power density for cutting.
請參閱第四圖為本發明之實施例所使用的反射鏡組6 ’係 包含一反射鏡61與兩顧可調整兩個象限角度的鈕62a及 62b，子光束s 21射向反射鏡61會產生折射’折射後之 行進方向可藉由旋鈕62a及62b來改變’其中一個旋鈕可 使光的行進方向在X轴上變化，另一個可使光的行進方向 在Y軸上變化，藉此便可將子光束S 21的聚焦光點調至所 需要之位置。Referring to the fourth figure, the mirror group 6' used in the embodiment of the present invention includes a mirror 61 and two buttons 62a and 62b which can adjust the two quadrant angles. The sub-beam s 21 is incident on the mirror 61. The direction of travel after the refraction 'refraction can be changed by the knobs 62a and 62b'. One of the knobs can change the direction of travel of the light on the X-axis, and the other can change the direction of travel of the light on the Y-axis. The focused spot of sub-beam S 21 can be adjusted to the desired position.
本發明所提供之分光系統係利用單一雷射母光束產生出 兩道切割用之子光束，此二道切割光束施加於一待加工 之晶圓表面的切割道上，可同時進行二切割道之加工， 因而提高晶圓切割之作業效率，此二光束之強度可調整 至相同，而且此二光束間距離可自由調整’不受兩道子 光束原始距離的約束，如此更可因應不同晶粒之需求。 综上所述’本發明較已知晶圓切割技術有明顯的架構簡 化與功能提升的進步性，尤其可單獨精準調校各子光束 功率，完全不受零件加工公差的影響，是最符合實際作 業需求的機構。 099113645 【圖式簡單說明】 表單編號A0101 第7頁/共14頁 0992024049-0 201136692 [0009] 第一圖：係本發明實施例之示意圖。 第二圖：係一晶圓之局部放大圖。 第三a~Sb圖：係本發明不同聚焦鏡之示意圖。 第四圖··係本發明所使用之反射鏡組示意圖。 【主要元件符號說明】 099113645 [0010] 1 雷射光源 2 濾、波器 3 半波片 4 光束擴大器 5 極化分光元件（PBS) 6 反射鏡組 7 偏光片 8 聚焦組 8a 複合鏡 8b 顯微鏡式聚焦鏡 9 晶圓 12 切割道 20 母光束 21 S子光束 22 P子光束 61 反射鏡 62a 調整旋鈕 62b 調整旋鈕 表單編號A0101 第8頁/共14頁 0992024049-0The spectroscopic system provided by the invention generates two sub-beams for cutting by using a single laser beam, and the two cutting beams are applied to a cutting surface of a surface of a wafer to be processed, and the processing of the two cutting lines can be simultaneously performed. Therefore, the efficiency of the wafer cutting operation is improved, the intensity of the two beams can be adjusted to be the same, and the distance between the two beams can be freely adjusted 'not constrained by the original distance of the two sub-beams, so that the requirements of different crystal grains can be met. In summary, the invention has obvious structural simplification and improved function improvement compared with the known wafer cutting technology. In particular, the sub-beam power can be precisely adjusted separately, completely independent of the machining tolerance of the part, and is most practical. The organization that needs the job. 099113645 [Simple description of the drawing] Form No. A0101 Page 7 of 14 0992024049-0 201136692 [0009] The first figure is a schematic diagram of an embodiment of the present invention. The second picture is a partial enlarged view of a wafer. The third a~Sb diagram is a schematic diagram of different focusing mirrors of the present invention. Figure 4 is a schematic view of a mirror set used in the present invention. [Main component symbol description] 099113645 [0010] 1 Laser source 2 Filter, waver 3 Half-wave plate 4 Beam expander 5 Polarization beam splitter (PBS) 6 Mirror group 7 Polarizer 8 Focus group 8a Composite mirror 8b Microscope Focusing mirror 9 Wafer 12 Cutting path 20 Mother beam 21 S sub-beam 22 P sub-beam 61 Mirror 62a Adjustment knob 62b Adjustment knob form No. A0101 Page 8 of 14 0992024049-0