201218273 六、發明說明： 【發明所屬之技術領域】 本發明係有關一種半導體雷射加工技術，特別是關於一種採用介電層 在矽晶圓雷射加工之方法。 【先前技術】 按，目前產品都朝向輕薄短小的方向發展，因此晶片係整合堆疊數層 結構，以縮小封裝的面積，此即為所謂的3D堆疊封裝之積體電路。其中， 最關鍵的技術是矽穿孔（Through Silicon Vias，TSV )製程，其係透過以垂 直導通來整合晶圓堆疊的方式，以達到晶片間的電氣互連，讓晶圓正面的 電子訊號透過穿孔（via)傳遞到晶圓背面，再與堆疊下面的晶片連繫，如 此可以省略傳統的銲墊（Bondpad)的位置，使晶片尺寸有效縮小。 針對石夕穿孔製程中’對石夕晶圓進行鑽孔係有兩種方式：電聚触刻以及 雷射鑽孔。電漿_的加玉齡合黃光製程，兩者的機台設備及生產環境 投資極為獻，且加卫時所使賴特殊氣體（SF6)也需要制的安全防範 裝置。後者雷射鑽孔的加工方式所使用之設備投資單純，機台維護容易， 但製程的光熱效益所產生⑽熔齡賴到·關表面，—部份會在入 口處產生魏輯疊，雜敎心，—雜雜㈣濺與找接觸冷卻 後會殘留树晶圓表面，分布像衛星群；如第—圖所示，在孔洞12附近之 此些殘留之火山口石夕熔渣14或衛星群雜潰16在後細晶圓1〇表面製作 圖案時，會影響後續製程及元件的可靠度，因此必須將它除去，目前都是 以研磨或濕儀刻方式去除，但效果不彰，且費工耗時。 另外，最新研究顯示’使用飛秒雷射（femt〇_nd 來進行石夕穿 201218273 孔加工可以避免上述現象發生， 獲仵好的加工品質丨然而，這類雷射的 加工速度駐業上量產的實際需求仍相差甚遠。 、有鑑於此，本發明遂提出一種採用介電層在石夕晶圓雷射加工之方法， 以改善存在於先前技術中之該等缺失。 【發明内容】 本發明之主要目的係在提供一種採用介電層在石夕晶圓雷射加工之方 法，其係_介電層之設計，在抑日圓雷射鑽孔加叫，可以有效改善孔 洞入口的火山Π以及孔洞周_衛星群雜渣分布_關題；並可使用 侧方式輕祕介電層去除，以制有效去除雜渣之功效者。 本發明之另-目的係在提供一種採用介電層在石夕晶圓雷射加工之方 法’其係糊賴《婦便宜之餘舰方絲進行加玉，轉決先前 技術於雷射時產生矽熔渣喷濺去除的問題。 為達到上述目的’本發明係在提供之石夕晶圓表面上形成一介電層，再 利用雷射加工射晶圓進行鑽孔，以形成至少一孔洞此時會在介電層上 形成有少量之火山口以及衛星群等之碎雜；最後，侧去除㈣圓上之 介電層，以同步去除介電層上之石夕溶邊。 底下藉由具體實施例配合所_圖式詳加說明，當更容易瞭解本發明 之目的、技術内容、特點及其所達成之功效。 【實施方式】 第二⑻圖至第工⑷圖係分別為本發明採用介電層在石夕晶圓雷射加工時 之各步驟構造剖視圖；魏，請先參閱第二⑻0所示，紐供—♦晶圓20， 再利用在石夕阳圓20上沈積形成一介電層（dieiectriciayer) 22，此介電層 201218273 係為二氧化石夕（Si〇2)或是說化石夕（Si3N4)等，介電層22若使用二氧化石夕， 則係利用化學氣相沉積技術或熱氧化技術形成於石夕晶圓20上；介電層22 右使用氮化矽，則係化學氣相沉積技術沈積於矽晶圓2〇上，其中化學氣相 沈積包含有低壓化學氣相沈積（LPCVD)以及電漿輔助化學氣相沈積 (PECVD)。其中介電層22係用來作為雷射鑽孔加工時之屏障層，以減少 火山口石夕熔潰之生成。 接續請參閱第二(b)圖所示，本發明利用雷射加工技術對矽晶圓2〇及其 • 上之介電層22進行鑽孔，去除部份石夕晶圓2〇及對應之部份介電層22以形 成至少一孔洞24以Q開關敍〇-雅络雷射（Q_switched Nd-YAG laser)波長 1064奈米，功率40瓦，脈衝長度35奈秒，脈衝頻率15千赫（kHz)來鑽 孔；此時雷射鑽孔過程所產生的矽熔渣喷濺冷卻後，將殘留在之前此介電 層22上’而在孔洞24周圍及附近會分別形成火山口石夕，熔渣26或衛星群秒 炫渣28。其中’在雷射鑽孔時，因為介電層22的能階（Bandgap)大於半 導體的矽晶圓20,所以習知移除介電層22所需的雷射能量相對大於矽晶圓 • 材料，本發明將此介電層22當作一屏障層，因此僅雷射光束中間較高能量 可以先移除介電層22，再對矽晶圓20之矽產生移除作用，而雷射高斯光束 邊緣一圈較低能量’將被介電層22遮蔽，故可有效減少火山口石夕溶潰26 的形成。 最後，蝕刻去除矽晶圓20上之介電層22，此步驟係使用用石夕/介電層 蝕刻選擇比大的化學蝕刻方式移除介電層22，介電層22上之碎溶潰26或 衛星群矽熔渣28亦同時被去除，完成後如第二(c)圖所示。當然，使用石夕/ 介電層蝕刻選擇比大的化學蝕刻方式可以很容易將這介電層22剝除，石夕·溶 201218273 邊也因此跟著去除’這樣可以有效的解決雷射鑽洞後，孔湖醜留的衛 星群的問題。 其中，上述實施例係以-個孔洞為例來說明，但本發明當不限定孔洞 之數目…個或-個以上或複數個孔洞，都適用於本發明之方法。 因此，本發明不但可以有效改善孔洞入口的火山口以及孔洞周圍的衛 星群德齡布殘㈣問題；再加上本發_使用設備投f相對便宜之雷 射鑽孔方式來進行雷射加工，並可解从前技術於雷射時產生雜潰喷減 去除的問題；可再使祕刻方式㈣將介f層去除，料到有效去除雜 渣之功效者’功效明顯勝於現有技術。 以上所述之實施例僅係為說明本發明之技術思想及特點其目的在使 熟習此項技藝之人士能夠瞭解本發明之内容並據讀施，當不能以之限定 本發明之專利範圍，即大凡依本發明所揭示之精神所作之均等變化或修 飾’仍應涵蓋在本發明之專利範圍内。 【圖式簡單說明】 第一圆為先前技術生成石夕熔潰之結構示意圖。 第二⑷圖至第二刚係分別為本發明採用介電層在碎晶圓雷射加工時之各 步驟構造剖視圖。 【主要元件符號說明】 矽晶圓 12孔洞 14火山口矽熔渣 衛星群矽熔渣 201218273 20破晶圓 22介電層 24孔洞 26火山口矽熔渣 28衛星群矽熔渣201218273 VI. Description of the Invention: [Technical Field] The present invention relates to a semiconductor laser processing technique, and more particularly to a method for laser processing using a dielectric layer on a germanium wafer. [Prior Art] According to the current products, the products are moving toward a light and short direction. Therefore, the chip is integrated with a plurality of layers to reduce the area of the package. This is the integrated circuit of the so-called 3D stacked package. Among them, the most critical technology is the Through Silicon Vias (TSV) process, which integrates the wafer stack by vertical conduction to achieve electrical interconnection between the wafers, allowing the electronic signals on the front side of the wafer to pass through the perforations. (via) is transferred to the back side of the wafer and then connected to the wafer under the stack, so that the position of the conventional bond pad can be omitted, and the size of the wafer can be effectively reduced. There are two ways to drill the Shixi wafer in the Shixi piercing process: electro-collecting and laser drilling. The plasma _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ The equipment used in the laser drilling method is simple to invest in, and the machine is easy to maintain, but the photothermal efficiency of the process is generated. (10) The smelting age depends on the surface, and some will produce Wei stack at the entrance. Heart, - Miscellaneous (4) Splashing and finding contact cooling will leave the surface of the tree wafer, distributed like a satellite group; as shown in the figure - the residual crater near the hole 12, the slag 14 or the satellite group When the pattern is formed on the surface of the fine wafer 1 杂, it will affect the reliability of subsequent processes and components. Therefore, it must be removed. It is currently removed by grinding or wet etching, but the effect is not good. Time spent. In addition, the latest research shows that 'the use of femtosecond lasers (femt〇_nd for Shi Xi wearing 201218273 hole processing can avoid the above phenomenon, and obtain good processing quality. However, the processing speed of such lasers is on the job. The actual demand for production is still far from the difference. In view of the above, the present invention proposes a method for laser processing using a dielectric layer in Shi Xi wafer to improve the defects existing in the prior art. The main purpose of the invention is to provide a method for laser processing using a dielectric layer in Shixi wafer, which is a dielectric layer design, which can effectively improve the volcanic crater at the entrance of the hole by suppressing the laser drilling of the Japanese yen. And the hole circumference _ satellite group slag distribution _ off-the-point; and the side mode light and secret dielectric layer removal can be used to effectively remove the effect of the slag. Another object of the present invention is to provide a dielectric layer The method of laser processing of Shixi wafers is based on the problem that the woman’s cheaper ship is added to the jade, and the previous technology is used to remove the slag splashing during the laser. hair Forming a dielectric layer on the surface of the provided ray wafer, and then drilling the laser using the laser to form at least one hole. At this time, a small number of craters and satellite groups are formed on the dielectric layer. Finally, the side removes the dielectric layer on the (four) circle to synchronously remove the Shiyue edge on the dielectric layer. The bottom part is explained in detail by the specific embodiment. The purpose of the invention, the technical content, the features and the effects achieved by the invention. [Embodiment] The second (8) to the fourth (4) drawings are respectively the steps of the steps of the invention using the dielectric layer in the laser processing of the Shixi wafer. Cross-sectional view; Wei, please refer to the second (8) 0, the new supply - ♦ wafer 20, and then deposited on the stone sunset circle 20 to form a dielectric layer (dieiectriciayer) 22, the dielectric layer 201218273 is a dioxide In the evening (Si〇2) or Fossil (Si3N4), if the dielectric layer 22 is made of silica dioxide, it is formed on the Shixi wafer 20 by chemical vapor deposition or thermal oxidation; Layer 22 is made of tantalum nitride on the right, which is a chemical vapor deposition technique. Deposited on the crucible wafer 2, wherein the chemical vapor deposition comprises low pressure chemical vapor deposition (LPCVD) and plasma assisted chemical vapor deposition (PECVD), wherein the dielectric layer 22 is used as a laser drilling process. The barrier layer at the time to reduce the formation of the crater meltdown. Continuing to refer to the second (b) diagram, the present invention utilizes laser processing techniques for the wafer 2 and its dielectric layer 22 Drilling, removing part of the Xi'er wafer 2〇 and corresponding part of the dielectric layer 22 to form at least one hole 24 to Q-switched Nd-YAG laser wavelength of 1064 nm, The power is 40 watts, the pulse length is 35 nanoseconds, and the pulse frequency is 15 kilohertz (kHz) for drilling; at this time, the slag generated by the laser drilling process is cooled and splashed, and remains on the previous dielectric layer 22. 'In the vicinity of and around the hole 24, a crater, a slag 26 or a satellite group, a second slag 28, is formed. Wherein, in the case of laser drilling, since the energy level of the dielectric layer 22 is larger than that of the semiconductor wafer 20, the laser energy required to remove the dielectric layer 22 is relatively larger than that of the germanium wafer. In the present invention, the dielectric layer 22 is regarded as a barrier layer. Therefore, only the middle energy of the laser beam can remove the dielectric layer 22 first, and then remove the germanium wafer 20, and the laser Gauss is removed. The lower energy of the edge of the beam will be shielded by the dielectric layer 22, so that the formation of the crater 26 can be effectively reduced. Finally, the dielectric layer 22 on the germanium wafer 20 is etched away. This step removes the dielectric layer 22 by using a lithography/dielectric layer etching option to remove the dielectric layer 22, and the dielectric layer 22 is broken. 26 or the satellite group slag 28 is also removed at the same time, as shown in the second (c). Of course, the use of the Shi Xi / dielectric layer etching option can easily remove the dielectric layer 22 than the large chemical etching method, and the Shi Xi·Solution 201218273 side is also removed. This can effectively solve the laser drilling hole. The problem of the satellite group left by the hole in the lake. The above embodiment is described by taking a hole as an example, but the present invention is applicable to the method of the present invention without limiting the number of holes, or more than one or a plurality of holes. Therefore, the present invention can not only effectively improve the crater of the entrance of the hole and the problem of the satellite group age (4) around the hole; in addition, the present invention uses the relatively inexpensive laser drilling method for laser processing. It can solve the problem that the former technology produces the phenomenon of the removal of the spray during the laser; the secret engraving mode (4) can be removed, and the effect of effectively removing the residual slag is obviously superior to the prior art. The embodiments described above are merely illustrative of the technical spirit and characteristics of the present invention, and the objects of the present invention can be understood by those skilled in the art and are not to be construed as limiting the scope of the invention. Equivalent changes or modifications made by the spirit of the present invention should still be covered by the scope of the present invention. [Simple description of the diagram] The first circle is a schematic diagram of the structure of the previous technology. The second (4) to second rigid lines are respectively sectional views of the steps of the dielectric layer in the laser processing of the wafer during the laser processing of the present invention. [Main component symbol description] 矽 wafer 12 holes 14 crater slag slag satellite group slag 201218273 20 broken wafer 22 dielectric layer 24 holes 26 crater slag slag 28 satellite group slag