201218413 六、發明說明： 【發明所屬之技術領域】 [0001] 本發明涉及-種二極體晶片製造方法，特別是指一種發 光二極體晶片製造方法。 [0002] C先前技術] 發光二極體憑藉其南光效、低能耗、無污染等優點，已 被應用於越來越多的場合之中，大有取代傳統光源的趨 勢。 0 [0003] 〇 習知的三族氮化物半導體發光二極體晶片通常是由一藍 寶石基板及生長在藍寶石基板上的三五族氮化合物發光 層所構成的。然而此種結構的晶片由於藍寶石導熱性較 差，導致整體散熱性能不佳，容易影響晶片的工作壽命 。因此，業界目前也有採用矽作為發光二極體晶片的基 板材料，以利用石夕基板相對較高的熱傳導率來提升晶片 的散熱性能。然而’由於碎本身的材料特性，將其作為 發光二極體晶片的基板材料將導致發光層的部分光線會 被其吸收，進而影響到晶片的出光效率。 [0004] 【發明内容】 因此，有必要提供一種出光效率較高的發光二極體晶片 製造方法。 [0005] 一種發光二極體晶片製造方法’包括步驟： [0006] 提供矽基板’該矽基板上生長有多個通過間隙彼此隔開 的磊晶層，各磊晶層之間的間隙底部具有阻隔層； [0007] 在間隙内填充絕緣材料； 099136845 表單編號A0101 第3頁/共28頁 0992064355-0 201218413 [0008] 在各磊晶層及絕緣材料頂面形成連續的金屬結構； [0009] 去除矽基板、阻隔層及絕緣材料； [0010] 在各磊晶層底面及金屬結構頂面形成對應的電極； [0011] 沿各間隙切割金屬結構而將各磊晶層分離。 [0012] 此發光二極體製造方法將原生長用矽基板去除，可防止 磊晶層所發出的光線被矽基板吸收的情況。並且，由於 還在發光二極體晶片的頂面形成有金屬鏡面反射結構， 因此磊晶層所發出的光線可被有效地進行反射，從而提 升發光二極體晶片的出.先效率:。. 【實施方式】 [0013] 請參閱圖1-16，示出了製造本發明發光二極體晶片的各 工藝流程。 [0014] 首先，如圖1提供一矽基板10。該矽基板10具有一平坦的 頂面，以方便進行各種工藝處理。 [0015] 然後，如圖2所示在矽基板1〇的頂面形成一光阻層20。該 光阻層20可以為G~iine正型光阻層、卜光阻層 、H-line正型光阻層或Duv正型光阻層。可以理解地， 該光阻層20還可以為與光罩設計及相關制程相適應的其 他類型的負型光阻層。 [0016] 再如圖3所示圖形化光阻層2〇，使之被分離為通過多個間 隙22隔開的多個獨立的島狀區域。對光阻層20進行圖形 化可採用曝光與顯影相結合的方式。具體而言，可以先 在光阻層20上方放置—開設有多個開槽的光罩（圖未示） 099136845 表單編號A0101 第4頁/共28頁 0992064355-0 201218413 [0017] Ο [0018]201218413 VI. Description of the Invention: [Technical Field] [0001] The present invention relates to a method for fabricating a diode chip, and more particularly to a method for fabricating a light-emitting diode wafer. [0002] Prior to the prior art, the light-emitting diode has been applied to more and more occasions due to its advantages of south light efficiency, low energy consumption, and no pollution, and has a tendency to replace the conventional light source. [0003] A conventional Group III nitride semiconductor light-emitting diode wafer is usually composed of a sapphire substrate and a three-five-group nitrogen compound light-emitting layer grown on a sapphire substrate. However, the wafer of this structure has poor thermal conductivity due to poor thermal conductivity of sapphire, which easily affects the working life of the wafer. Therefore, the industry currently uses ruthenium as a substrate material for a light-emitting diode wafer to utilize the relatively high thermal conductivity of the shishan substrate to improve the heat dissipation performance of the wafer. However, due to the material properties of the chip itself, using it as a substrate material for the light-emitting diode wafer will cause a part of the light of the light-emitting layer to be absorbed by it, thereby affecting the light-emitting efficiency of the wafer. SUMMARY OF THE INVENTION Therefore, it is necessary to provide a method of manufacturing a light-emitting diode wafer having high light extraction efficiency. [0005] A method for fabricating a light-emitting diode wafer includes the following steps: [0006] providing a germanium substrate, wherein the germanium substrate is grown with a plurality of epitaxial layers separated from each other by a gap, and the bottom of each gap between the epitaxial layers has a barrier layer; [0007] filling the gap with an insulating material; 099136845 Form No. A0101 Page 3 of 28 0992064355-0 201218413 [0008] Forming a continuous metal structure on each of the epitaxial layers and the top surface of the insulating material; [0009] Removing the germanium substrate, the barrier layer, and the insulating material; [0010] forming corresponding electrodes on the bottom surface of each of the epitaxial layers and the top surface of the metal structure; [0011] cutting the metal structures along the gaps to separate the epitaxial layers. [0012] This method of manufacturing a light-emitting diode removes the original growth germanium substrate, and prevents light emitted from the epitaxial layer from being absorbed by the germanium substrate. Moreover, since a metal specular reflection structure is also formed on the top surface of the light-emitting diode wafer, the light emitted from the epitaxial layer can be effectively reflected, thereby improving the efficiency of the light-emitting diode wafer. [Embodiment] [0013] Referring to Figures 1-16, various process flows for fabricating a light-emitting diode wafer of the present invention are shown. [0014] First, a germanium substrate 10 is provided as shown in FIG. The ruthenium substrate 10 has a flat top surface to facilitate various processing. [0015] Then, as shown in FIG. 2, a photoresist layer 20 is formed on the top surface of the germanium substrate 1A. The photoresist layer 20 may be a G~iine positive photoresist layer, a photoresist layer, an H-line positive photoresist layer or a Duv positive photoresist layer. It will be appreciated that the photoresist layer 20 can also be other types of negative photoresist layers that are compatible with the reticle design and associated processes. [0016] The photoresist layer 2 is patterned as shown in FIG. 3 to be separated into a plurality of independent island regions separated by a plurality of gaps 22. Patterning the photoresist layer 20 may be a combination of exposure and development. Specifically, it may be placed above the photoresist layer 20 - a plurality of slotted photomasks are provided (not shown). 099136845 Form No. A0101 Page 4 / Total 28 Pages 0992064355-0 201218413 [0017] Ο [0018]
[0019] 099136845 ，然後通過紫外線曝光使暴露在光罩開槽内的部分光阻 層20發生光化學反應，再通過顯觀的作用將發生光化 學反應的該部分光阻層20溶解，從而切基板1()上殘留 下未經過曝光的島狀光阻層2〇。 之後，將料圖形化光阻層2G_基板1Q置於富氧或純 氮的環境中進行加熱，使暴露在各島狀光阻層2〇之間的 間隙22底面的矽基板1〇表面被氧化或氤化為氧化矽或氮 化矽。該加熱溫度優選在12(M50攝氏度，以使反應更加 充分。若使用部分特殊耐高溫的光阻材料，可進—步將 溫度提升至200~250攝氏度。如圖4所示，該氧化矽或氮 化矽在本實施例中為一阻隔層丨2 ,可起到阻止相應的半 導體結構生長的作用。 隨後，以去光阻液洗去矽基板10上的所有的光阻層2〇 , 從而如圖5所不僅在矽基板1〇表面留下間隔設置的阻隔層12。 然後如圖6所示，在矽基板10表面形成一磊晶層3〇，該磊 晶層30包括依次生長的一 N型半導體層32、一發光層34及 一 P型半導體層36。該磊晶層3〇的材料可選擇自氮化鎵、 氮化銦鎵等三五族氮化物或其他族系的半導體材料，具 體取決於實際的光學需求。此外，在N型半導體層32生長 之前還可以在矽基板1〇表面先生長一缓衝層（圖未示）， 用於改善磊晶層30的生長品質。由於阻隔層12的作用， 磊晶層30將不會生長在阻隔層丨2表面而被隔離形成多個 獨立的島狀區域。各阻隔層12上方由於未被磊晶層30所 填充而形成相應的溝槽300。另外，為避免呈島狀分佈的 第5頁/共28頁 表單編號A0I01 0992064355-0 201218413 各磊晶層30在阻隔層12表面上方橫向生長到一定的程度 時發生彼此連接的現象，本實施例中將溝槽300的寬度控 制為大於兩倍的遙晶層30的南度。 [0020] 再如圖7所示在各磊晶層3 0之間的溝槽3 0 0内填充絕緣材 料40，使磊晶層30的頂面與絕緣材料40的頂面齊平。該 絕緣材料40可由與光阻層20或阻隔層12相同或相近的材 料所製成。優選地，可採用與光阻層20相同的材料製造 絕緣材料40，因為光阻材料的孔洞填充性較佳，容易製 作與蟲晶層30頂面齊平的表面。 [0021] 然後，如圖8所示在磊晶層30及絕緣材料40的頂面通過電 子束（E-gun)或電漿輔助化學氣相沉積（Plasma Enhanced Chemical Vapor Deposition, PECVD) 等方 法形成一連續的反射膜50。該反射膜50可採用鋁、金或 銀等金屬材料製成。該反射膜50的作用在於將發光層34 的光線反射出發光二極體晶片外，以提升整體的出光效 率。 [0022] 之後，如圖9所示通過電子束或電漿輔助化學氣相沉積等 方法在反射膜50表面繼續形成一金屬蒸鍍層60，其起到 一過渡層的作用，用於在反射膜50上接合其他的結構層 。該蒸鍍層60的材質也可選自鋁、金、鉻及銀等金屬材 料。 [0023] 隨後如圖10所示在蒸鍍層60頂面電鍍一層金屬基板70。 該金屬基板70的主要作用有三：第一是用於對磊晶層30 進行散熱，以確保其能夠穩定地工作；第二是作為電流 099136845 表單編號A0101 第6頁/共28頁 0992064355-0 201218413 [0024] Ο [0025] [0026] ❸ [0027] [0028] 傳導元件將電流輸入發光層34内；第三是作為支撐元件 承載磊晶層30。該金屬基板70可採用鋁、銅、金、銀等 材料製成’其厚度遠大於蒸鍍層60及反射膜5〇的厚度。 然後’如圖11所示在上述金屬結構（包括金屬基板7〇、反 射膜50及蒸鍍層6〇)、磊晶層30及矽基板1〇的周圍形成 一保護層80。該保護層80未覆蓋矽基板10的底面以使石夕 基板暴露在外，方便後續的腐蝕過程。保護層8〇可採用 對腐蝕劑有耐性的材料所製成，比如蠟或其他常用的耐 腐蚀材料。 之後如圖12所示通適腐蝕劑蔣矽基板1〇完全去除掉，暴 露出位於矽基板1〇上方的磊晶層30底面及阻隔層12由 於保護層80的作用’金屬結構被保護起來而未受腐餘劑 的影響。 接著如圖13所示通過腐蝕或其他方式去除阻隔層丨2及絕 緣材料40，使各磊晶層30間的溝槽300頂部的反射媒5〇 暴露出來。 隨即如圖14再將包圍金屬結構及磊晶層30的保護層8〇去 除，使金屬結構及磊晶層30暴露出來。 然後如圖15所示，再在各磊晶層30的底面形成Ν型電極38 ，並在金屬基板70底面對應各蠢晶層30的位置處形成多 個Ρ型電極39，其中這些ρ型電極39與Ν型電極38— 一對 應0 [0029] 099136845 最後’沿各蟲晶層30的溝槽300對金屬結構進行切割 而分割為如圖16所示的多個獨立的發光二極體晶片。 表單編號Α0101 第7頁/共28頁 從 0992064355-0 201218413 [0030] 由於在蟲晶層30的頂面形成有金屬反射膜5〇並同時去除 了原吸光的矽基板10，因此發光層34發出的光線可被反 射膜50反射出發光二極體晶片外，避免由於矽基板1〇吸 光而導致發光二極體晶片出光效率下降的情形。並且， 由於採用金屬基板70連接p型電極39及磊晶層3〇，發光二 極體晶片由於發光而產生的熱量可被金屬基板7〇快速地 散發到外部，從而確保其正常工作。此外，通過在矽基 板10表面形成多個阻隔層12而使磊晶層30以島狀區域的 形式在矽基板10表面生長，可有效減少由於生長過程中 的應力累積以及與矽基板1〇熱膨脹係數的差異而導致磊 晶層30出現破裂的情形，使磊晶層3〇的生長品質得到保 障。 [0031] 綜上所述，本發明符合發明專利要件，爰依法提出專利 申請。惟，以上所述者僅為本發明之較佳實施例，舉凡 熟悉本案技藝之人士，在爰依本發明精神所作之等效修 飾或變化’皆應涵蓋於以下之申請專利範:圍内。 【圖式簡單說明】 [0032] 圖1示出了製造本發明的發光二極體晶片的第一個步驟。 [0033] 圖2示出了製造本發明的發光二極體晶片的第二個步驟。 [0034] 圖3示出了製造本發明的發光二極體晶片的第三個步驟。 [0035] 圖4示出了製造本發明的發光二極體晶片的第四個步驟。 [0036] 圖5示出了製造本發明的發光二極體晶片的第五個步驟。 [0037] 圖6示出了製造本發明的發光二極體晶片的第六個步驟。 099136845 表單編號A0101 第8頁/共28頁 0992064355-0 201218413 [0038] 圖7示出了製造本發明的發光二極體晶片的第七個步驟。 [0039] 圖8示出了製造本發明的發光二極體晶片的第八個步驟。 [0040] 圖9示出了製造本發明的發光二極體晶片的第九個步驟。 [0041] 圖10示出了製造本發明的發光二極體晶片的第十個步驟 [0042] 圖11示出了製造本發明的發光二極體晶片的第十一個步 驟。[0019] 099136845, then a part of the photoresist layer 20 exposed to the reticle of the reticle is photochemically reacted by ultraviolet exposure, and then the portion of the photoresist layer 20 where the photochemical reaction occurs is dissolved by the apparent action, thereby cutting An unexposed island-shaped photoresist layer 2 残留 remains on the substrate 1 (). Thereafter, the patterned photoresist layer 2G_substrate 1Q is placed in an oxygen-rich or pure nitrogen atmosphere to be heated, so that the surface of the germanium substrate 1 exposed on the bottom surface of the gap 22 between the island-shaped photoresist layers 2 is Oxidized or deuterated to yttria or tantalum nitride. The heating temperature is preferably 12 (M50 degrees Celsius) to make the reaction more sufficient. If some special high temperature resistant photoresist material is used, the temperature can be further increased to 200 to 250 degrees Celsius. As shown in Fig. 4, the cerium oxide or The tantalum nitride is a barrier layer 丨2 in this embodiment, which can prevent the growth of the corresponding semiconductor structure. Subsequently, all the photoresist layers 2 on the ruthenium substrate 10 are washed away by the photoresist. As shown in FIG. 5, not only the barrier layer 12 is disposed on the surface of the ruthenium substrate 1 . Then, as shown in FIG. 6 , an epitaxial layer 3 形成 is formed on the surface of the ruthenium substrate 10 , and the epitaxial layer 30 includes a sequentially grown one. The N-type semiconductor layer 32, an illuminating layer 34 and a P-type semiconductor layer 36. The material of the epitaxial layer 3 可选择 can be selected from a gallium nitride, an indium gallium nitride or the like, a tri-five nitride or other semiconductor material. Depending on the actual optical requirements, in addition, before the growth of the N-type semiconductor layer 32, a buffer layer (not shown) may be formed on the surface of the germanium substrate 1 to improve the growth quality of the epitaxial layer 30. Due to the action of the barrier layer 12, the epitaxial layer 30 will not grow. A plurality of independent island-like regions are formed on the surface of the barrier layer 丨 2. The upper portion of each of the barrier layers 12 is not filled by the epitaxial layer 30 to form a corresponding trench 300. In addition, in order to avoid an island-like distribution 5 pages/total 28 pages Form No. A0I01 0992064355-0 201218413 When the epitaxial layers 30 are laterally grown to a certain extent above the surface of the barrier layer 12, a phenomenon of connecting to each other occurs, and in this embodiment, the width of the trench 300 is controlled to be larger than Two times the south of the crystal layer 30. [0020] Further, as shown in FIG. 7, the insulating material 40 is filled in the trench 300 between the epitaxial layers 30, so that the top surface of the epitaxial layer 30 is The top surface of the insulating material 40 is flush. The insulating material 40 may be made of the same or similar material as the photoresist layer 20 or the barrier layer 12. Preferably, the insulating material 40 may be made of the same material as the photoresist layer 20, Since the hole filling property of the photoresist material is better, it is easy to form a surface flush with the top surface of the crystal layer 30. [0021] Then, as shown in FIG. 8, the electron beam is passed through the top surface of the epitaxial layer 30 and the insulating material 40. (E-gun) or plasma-assisted chemical vapor deposition (Plasma Enhanced Chemical V Apor Deposition, PECVD) or the like forms a continuous reflective film 50. The reflective film 50 may be made of a metal material such as aluminum, gold or silver. The reflective film 50 functions to reflect the light of the light-emitting layer 34 out of the light-emitting diode. Outside the wafer, to improve the overall light extraction efficiency. [0022] Thereafter, as shown in FIG. 9, a metal evaporation layer 60 is continuously formed on the surface of the reflective film 50 by electron beam or plasma-assisted chemical vapor deposition or the like, which serves as a The role of the transition layer is to bond other structural layers on the reflective film 50. The material of the vapor deposition layer 60 may also be selected from metal materials such as aluminum, gold, chromium, and silver. [0023] Subsequently, a metal substrate 70 is plated on the top surface of the vapor deposition layer 60 as shown in FIG. The metal substrate 70 has three main functions: the first is for dissipating the epitaxial layer 30 to ensure its stable operation; the second is for current 099136845 Form No. A0101 Page 6 / Total 28 Page 0992064355-0 201218413 [0024] [0028] The conductive element inputs current into the light-emitting layer 34; the third is to carry the epitaxial layer 30 as a support element. The metal substrate 70 may be made of a material such as aluminum, copper, gold or silver, and its thickness is much larger than the thickness of the vapor-deposited layer 60 and the reflective film 5A. Then, as shown in Fig. 11, a protective layer 80 is formed around the metal structure (including the metal substrate 7, the reflective film 50, and the vapor-deposited layer 6), the epitaxial layer 30, and the tantalum substrate 1A. The protective layer 80 does not cover the bottom surface of the ruthenium substrate 10 to expose the shishan substrate to facilitate subsequent etching processes. The protective layer 8 can be made of a material resistant to an etchant such as wax or other commonly used corrosion resistant materials. Then, as shown in FIG. 12, the common etchant Jiang 矽 substrate 1 〇 is completely removed, exposing the bottom surface of the epitaxial layer 30 above the 矽 substrate 1 及 and the barrier layer 12 due to the role of the protective layer 80 'the metal structure is protected Affected by the residual agent. Next, the barrier layer 丨 2 and the insulating material 40 are removed by etching or other means as shown in Fig. 13, and the reflective medium 5 顶部 at the top of the trench 300 between the epitaxial layers 30 is exposed. Then, the protective layer 8 surrounding the metal structure and the epitaxial layer 30 is removed as shown in Fig. 14, and the metal structure and the epitaxial layer 30 are exposed. Then, as shown in FIG. 15, a Ν-type electrode 38 is further formed on the bottom surface of each of the epitaxial layers 30, and a plurality of Ρ-type electrodes 39 are formed at positions corresponding to the respective sinite layers 30 on the bottom surface of the metal substrate 70, wherein the ρ-type electrodes are formed. 39 and Ν-type electrode 38 - a corresponding 0 [0029] 099136845 Finally, the metal structure is cut along the trench 300 of each of the crystal layer 30 to be divided into a plurality of independent light-emitting diode wafers as shown in FIG. Form No. 1010101 Page 7 of 28 From 0992064355-0 201218413 [0030] Since the metal reflective film 5 is formed on the top surface of the crystal layer 30 and the original light-absorbing ruthenium substrate 10 is simultaneously removed, the luminescent layer 34 is emitted. The light can be reflected by the reflective film 50 out of the light-emitting diode wafer, thereby avoiding a situation in which the light-emitting diode wafer light-emitting efficiency is lowered due to the light absorption by the germanium substrate 1. Further, since the p-type electrode 39 and the epitaxial layer 3 are connected by the metal substrate 70, the heat generated by the light-emitting diode wafer due to the light emission can be quickly dissipated to the outside by the metal substrate 7, thereby ensuring normal operation. In addition, by forming a plurality of barrier layers 12 on the surface of the germanium substrate 10, the epitaxial layer 30 is grown on the surface of the germanium substrate 10 in the form of island regions, which can effectively reduce stress accumulation during growth and thermal expansion with the germanium substrate 1 The difference in the coefficient causes the epitaxial layer 30 to be broken, so that the growth quality of the epitaxial layer 3 is ensured. [0031] In summary, the present invention complies with the requirements of the invention patent, and submits a patent application according to law. The above description is only the preferred embodiment of the present invention, and equivalent modifications or variations made by those skilled in the art of the present invention should be included in the following patent application. BRIEF DESCRIPTION OF THE DRAWINGS [0032] FIG. 1 shows a first step of fabricating a light-emitting diode wafer of the present invention. [0033] FIG. 2 shows a second step of fabricating a light emitting diode wafer of the present invention. [0034] FIG. 3 illustrates a third step in fabricating a light emitting diode wafer of the present invention. 4 shows a fourth step of fabricating a light emitting diode wafer of the present invention. [0036] FIG. 5 illustrates a fifth step in the fabrication of a light emitting diode wafer of the present invention. [0037] FIG. 6 shows a sixth step of fabricating a light emitting diode wafer of the present invention. 099136845 Form No. A0101 Page 8 of 28 0992064355-0 201218413 [0038] FIG. 7 shows a seventh step of fabricating the LED of the present invention. [0039] FIG. 8 illustrates an eighth step of fabricating a light emitting diode wafer of the present invention. [0040] FIG. 9 illustrates a ninth step of fabricating a light emitting diode wafer of the present invention. 10 shows a tenth step of fabricating a light-emitting diode wafer of the present invention. [0042] FIG. 11 shows an eleventh step of fabricating the light-emitting diode wafer of the present invention.
[0043] 圖12示出了製造本發明的發光二極體晶片的第十二個步 驟。 [0044] 圖13示出了製造本發明的發光二極體晶片的第十三個步 驟。 [0045] 圖14示出了製造本發明的發光二極體晶片的第十四個步 驟。 [0046] 圖15示出了製造本發明的發光二極體晶片的第十五個步 驟。 [0047] 圖16示出了製造本發明的發光二極體晶片的第十六個步 驟。 【主要元件符號說明】 [0048] 矽基板：10 [0049] 阻隔層：12 [0050] 光阻層：20 [0051] 間隙：22 099136845 表單編號A0101 第9頁/共28頁 0992064355-0 201218413 [0052] 蟲晶層.3 0 [0053] 溝槽：300 [0054] N型半導體層： 32 [0055] 發光層：34 [0056] P型半導體層： 36 [0057] N型電極：38 [0058] P型電極：39 [0059] 絕緣材料：40 [0060] 反射膜：50 [0061] 蒸鍍層：60 [0062] 金屬基板：70 [0063] 保護層：80 099136845 表單編號A0101 第10頁/共28頁 0992064355-0[0043] Figure 12 shows a twelfth step of fabricating a light emitting diode wafer of the present invention. [0044] Figure 13 shows a thirteenth step of fabricating a light emitting diode wafer of the present invention. [0045] Figure 14 shows a fourteenth step of fabricating a light emitting diode wafer of the present invention. [0046] Figure 15 shows a fifteenth step of fabricating a light emitting diode wafer of the present invention. [0047] Figure 16 shows a sixteenth step of fabricating a light emitting diode wafer of the present invention. [Main component symbol description] [0048] 矽 substrate: 10 [0049] Barrier layer: 12 [0050] Photoresist layer: 20 [0051] Gap: 22 099136845 Form No. A0101 Page 9 / Total 28 Page 0992064355-0 201218413 [ 0052] worm layer. 3 0 [0053] Trench: 300 [0054] N-type semiconductor layer: 32 [0055] luminescent layer: 34 [0056] P-type semiconductor layer: 36 [0057] N-type electrode: 38 [0058 P-type electrode: 39 [0059] Insulation material: 40 [0060] Reflective film: 50 [0061] Evaporation layer: 60 [0062] Metal substrate: 70 [0063] Protective layer: 80 099136845 Form No. A0101 Page 10 / Total 28 pages 0992064355-0