200950134 九、發明說明： 【發明所屬之技術領域】 本發明係有關一種LED晶粒的低溫金屬黏合層，特別 是針對於金屬钻著（Metal Bonding)晶粒，應用於接合發 光二極體磊晶層於基板上的金屬黏合層。 【先前技術】 發光二極體（Light Emitting Diode, LED)是一種冷 光發光元件，其發光原理是在ΠΙ-V族化合物半導體材料 ® 上施加電流，利用二極體内電子與電洞互相結合，而將能 量轉換為光的形式，能量釋出時便可以發光，且使用久也 不會像白熾燈泡般地發燙。發光二極體的優點在於體積 小、壽命長、驅動電壓低、反應速率快、耐震性特佳，能 夠配合各種設備的輕、薄及小型化的需求，早已成為曰常 生活中十分普及的產品。 發光二極體目前的發光性能表現及效率日益進步，可 以廣泛的應用在曰常生活中，其種類繁多，利用各種化合 11 物半導體材料及元件結構的變化，可設計出發紅、橙、黃、 綠、藍、紫等各顏色的光，以及紅外光、紫外光等不可見 光之發光二極體，各種發光二極體已廣泛應用在戶外看 板、煞車燈、交通號誌燈及顯示器等。 發光二極體中主要組成是發光二極體磊晶層，又稱 LED晶片（Chip)，為發光的半導體材料。發光二極體磊晶 層可由I呂鎵銦鱗（A1 Gal nP)等四元元素沉積而成，或填化 錄（GaP)、或蘇I呂石申（GaAlAs)，或是由石申化蘇（GaAs)、氮 200950134 化鎵（GaN)等半導體材料組成，其内部結構為一個PN結 構，具有單向導電性。 發光二極體的結構中，有一種金屬粘著（Metal Bonding)晶粒係透過一金屬黏合層來接合發光二極體磊 晶層和基板（Substrate)，該金屬黏合層同時做為反射 面，可用以反射光子’避免光子被基板吸收，可提升發光 二極體之外部量子效率。 現有的該金屬黏合層的組成係為金錫（AuSn)或金鎳 ® (AuNi)薄膜，其形成該基板的黏貼表面，其與形成於發光 二極體遙晶層的接合表面上，含銀（Ag)反射面的導電層黏 合。但，金錫（AuSn)或金鎳（AuNi)薄膜係為熔點高的材 料’使得目前的發光二極體磊晶層與基板的黏合製程需在 黏合溫度300至900°C，與黏合壓力500至5000磅的情況 下進行。高達300至900°C的黏合溫度將會使得金屬黏合 層中作為導電層的銀（Ag)或鋁（A1)被破壞，導致反射面的 結構遭到破壞。200950134 IX. Description of the Invention: [Technical Field] The present invention relates to a low-temperature metal bonding layer of an LED die, particularly for metal bonding die, for bonding LED epitaxial a metal bonding layer layered on the substrate. [Prior Art] A Light Emitting Diode (LED) is a luminescent light-emitting element whose principle of light is applied to a ΠΙ-V compound semiconductor material®, and the electrons and holes in the diode are combined with each other. In the form of converting energy into light, it can be illuminated when the energy is released, and it will not burn like an incandescent bulb for a long time. The advantages of the light-emitting diode are small volume, long life, low driving voltage, fast reaction rate, and excellent shock resistance. It can meet the needs of light, thin and miniaturized equipment, and has become a popular product in everyday life. . The current luminescent performance and efficiency of LEDs are increasingly advanced, and they can be widely used in ordinary life. They are available in a variety of ways, and can be designed to red, orange, yellow, etc. by using various semiconductor materials and component structures. Green, blue, purple and other colors of light, as well as infrared light, ultraviolet light and other invisible light-emitting diodes, a variety of light-emitting diodes have been widely used in outdoor billboards, brake lights, traffic lights and displays. The main component of the light-emitting diode is a light-emitting diode epitaxial layer, also known as an LED chip, which is a light-emitting semiconductor material. The epitaxial layer of the light-emitting diode can be deposited by quaternary elements such as I1 Gal nP, or filled with GaP or GaAlAs, or by Shi Shenhua (GaAs). Nitrogen 200950134 Gallium (GaN) and other semiconductor materials, its internal structure is a PN structure, with unidirectional conductivity. In the structure of the light-emitting diode, a metal bond (Metal Bonding) die is bonded to the light-emitting diode epitaxial layer and the substrate through a metal adhesive layer, and the metal adhesive layer serves as a reflective surface at the same time. It can be used to reflect photons' to avoid photons being absorbed by the substrate, which can improve the external quantum efficiency of the light-emitting diode. The existing metal bonding layer is composed of a gold-tin (AuSn) or gold-nickel (AuNi) film, which forms an adhesive surface of the substrate, and is formed on the bonding surface formed on the remote layer of the light-emitting diode, and contains silver. The conductive layer of the (Ag) reflective surface is bonded. However, the gold-tin (AuSn) or gold-nickel (AuNi) film is a material with a high melting point', so that the current bonding process of the epitaxial layer of the light-emitting diode and the substrate needs to be at a bonding temperature of 300 to 900 ° C, and a bonding pressure of 500. Carry out to 5000 pounds. A bonding temperature of up to 300 to 900 ° C causes destruction of silver (Ag) or aluminum (A1) as a conductive layer in the metal bonding layer, resulting in destruction of the structure of the reflecting surface.
A 【發明内容】 於是，本發明之主要目的在於解決金屬粘著晶粒之發 光二極體磊晶層與基板的黏合溫度過高的問題，透過改變 該金屬黏合層的材料組成’解決黏合溫度過高，金屬薄膜 被破壞的問題，提昇發光二極體之製造良率。 本發明解決技術問題所採用的技術方案是，提供一種 LED晶粒的低溫金屬黏合層應用於接合一發光二極體蠢晶 層於一基板上，該LED晶粒的低溫金屬黏合層包括：一第 200950134 -金屬層，其設置於該發光二極體義晶層的接合表面，該 第-金屬層於該發光二極體Μ層的最外表面有—金（Au) 層；以及-第二金屬層，其設置於該基板的接合表面，該 第二金屬層於該基板的最外表面有一姻（In)層，以藉由該 姻（In)層的低熔點特性，形成相對低溫的金屬黏合層。 本發明的優點在於透過設置於該基板的接合表面之 第二金屬層的銦（In)層的低溶點特性，使該金屬 黏合層使 該發光二極體I晶層與該基板的黏合製程的黏合溫度在 100C至300 C之間就可以操作，相較於習知的3〇〇。(：至9〇〇 C的低溫，在不影響電性連接效果的情形下，本發明可以 增加製程的容易度，提昇發光二極體之金屬粘著晶粒的良 率。 【實施方式】 茲有關本發明的詳細内容及技術說明，現以實施例來 作進一步說明，但應瞭解的是，該等實施例僅為例示說明 ❹之用，而不應被解釋為本發明實施之限制。 請參閱圖1 ’其為一發光二極體磊晶層10，該發光二 極體蟲晶層10至少包括一電子供應層（electron supply layer) 11、一電洞供應層（hole supply layer) 13 以及 一活化層（active layer) 12。發光二極體磊晶層l〇是透 過有機金屬氣相沉積磊晶方法（M0VCD)、液相磊晶方法 (LPE)或分子束磊晶方法（MBE)等其中之一方法製成。其中 該活化層可以是由包令—氮化銘姻錄（All nGaN )之週期結 構形成的多層量子井（Multiple quantum well，MQW)結構 7 200950134 做為發光區，而該畲 认 χτ ,— 卞供應層（electron supply layer) 11 為N型氮化嫁或氮彳卜细松&A SUMMARY OF THE INVENTION Accordingly, the main object of the present invention is to solve the problem that the bonding temperature of the epitaxial layer of the light-emitting diode of the metal adhered crystal grain and the substrate is too high, and to solve the adhesive temperature by changing the material composition of the metal adhesive layer. If the metal film is too high, the problem of the destruction of the metal film is improved, and the manufacturing yield of the light-emitting diode is improved. The technical solution adopted by the present invention is to provide a low-temperature metal bonding layer of an LED die for bonding a light-emitting diode stray layer on a substrate, and the low-temperature metal bonding layer of the LED die includes: No. 200950134 - a metal layer disposed on a bonding surface of the light emitting diode layer, the first metal layer having a gold (Au) layer on an outermost surface of the light emitting diode layer; and - a second a metal layer disposed on a bonding surface of the substrate, the second metal layer having an In (In) layer on an outermost surface of the substrate to form a relatively low temperature metal by a low melting point characteristic of the (In) layer Adhesive layer. The invention has the advantages that the low adhesion point characteristic of the indium (In) layer of the second metal layer disposed on the bonding surface of the substrate causes the metal bonding layer to bond the LED layer of the light emitting diode to the substrate. The bonding temperature can be operated between 100C and 300C, compared to the conventional 3〇〇. (: The low temperature of 9 〇〇C, the present invention can increase the ease of the process and improve the yield of the metal bonded crystal grains of the light-emitting diode without affecting the electrical connection effect. [Embodiment] The detailed description of the present invention and the technical description of the present invention are further illustrated by the embodiments, but it should be understood that these embodiments are only for the purpose of illustration and description Referring to FIG. 1 , which is an LED epitaxial layer 10 , the LED layer 10 includes at least an electron supply layer 11 , a hole supply layer 13 , and An active layer 12. The light-emitting diode epitaxial layer is transported by an organometallic vapor deposition epitaxy method (M0VCD), liquid phase epitaxy (LPE) or molecular beam epitaxy (MBE), etc. One of the methods is formed, wherein the active layer may be a multi-layer quantum well (MQW) structure 7 200950134 formed by the periodic structure of the package--Nan nGaN as the light-emitting region, and The 畲 χ χ, — Supply layer (electron supply layer) 11 is N-type nitride or nitrogen married fine loose left foot Bu &
鋼鎵材料製成，該電洞供應層13為P 型氮化鎵或氮化銦鎵材料製成。 ❹ 又該電/同供應層13表面形成-第-金屬層21 ’該第 金屬層21依序包含一氧化銦錫（ΙΤ0)層2U、一銀（Ag) 層212、一鈦㈤層213、一始（pt)層214與一金（Au)層 215於該發光二極體磊晶層1〇的電洞供應層13表面。此 外該氧化銦錫（ΙΤ0)層211與該電洞供應層13之間可以設 置一金鈹（AuBe)合金墊216,以增加該氧化銦錫（IT〇)層 211與該電洞供應層13的電性傳導率。 又睛參閱圖2’基板30的表面上形成有一第二金屬声 22。該基板30係一種局熱導係數基板，該基板％之材質 可以選自石夕（Si)、铭（A1)、銅（Cu)、銀（Ag)、碳化石夕 (SiC)、鑽石（diamond)、石墨（graphite)、钥 (Molybdenum)、及氮化鋁（Aluminum nitride)之中的任— ❹種。該第二金屬層22於該基板30表面依序包含一欽（Ti) 層221、一金（Au)層222與一銦（In)層223,其中該銦（ιη) 層223的厚度為〜4/zm。 清參閱圖3 ’該發光一極體蠢晶層10表面上的第一金 屬層21’為與基板30上的第二金屬層22黏合，第一金屬 層21與第二金屬層22黏合而形成一金屬黏合層2〇，亦即 其為讓該第二金屬層22中的銦（In)層223與該第一金屬 層21中的金（Au)層215黏合。因而其可藉由該第二金屬 200950134 層22上的銦（In)層223的低熔點特性，該金屬黏合層20 可使該發光二極體磊晶層10與該基板30的黏合製程在黏 合溫度介於100°C至300°C之間與黏合壓力500至5000磅 的情況下進行。 在黏合溫度相較於習知的300°C至900°C的低溫，使 該金屬黏合層20在黏合溫度介於100°C至300°C之間就可 以完成製程，在不影響電性連接效果的情形下，就可增加 組裝的容易度，提昇發光二極體之金屬粘著晶粒的良率。 最後，當該發光二極體磊晶層10藉由該金屬黏合層 20黏合於該基板30後，於該發光二極體磊晶層10上方， 即該電子供應層11上形成一歐姆接觸層40，如是完成發 光二極體的金屬粘著晶粒製作。 惟上述僅為本發明之較佳實施例而已，並非用來限定 本發明實施之範圍。即凡依本發明申請專利範圍所做的均 等變化與修飾，皆為本發明專利範圍所涵蓋。 200950134 1 【圖式簡單說明】 圖1為本發明實施低溫金屬黏合層的發光二極體磊晶層 結構示意圖。 圖2為本發明實施低溫金屬黏合層的基板結構示意圖。 圖3為本發明實施低溫金屬黏合層的發光二極體結構示 意圖。 【主要元件符號說明】 10 .發光二極體蠢晶層 11 :電子供應層 12 :活化層 ' 13 :電洞供應層 20 :金屬黏合層 21 :第一金屬層 211 :氧化銦錫層 212 :銀層 ❹ 213 :鈦層 214 :鉑層 215 :金層 216 :金鈹合金墊 22 :第二金屬層 221 :鈦層 222 :金層 223 :銦層 30 :基板 200950134 40 :歐姆接觸層Made of a steel gallium material, the hole supply layer 13 is made of a P-type gallium nitride or an indium gallium nitride material. Further, the surface of the electric/same supply layer 13 is formed - a first metal layer 21'. The metal layer 21 sequentially comprises an indium tin oxide (ITO) layer 2U, a silver (Ag) layer 212, and a titanium (five) layer 213. A first (pt) layer 214 and a gold (Au) layer 215 are on the surface of the hole supply layer 13 of the light emitting diode epitaxial layer 1 . In addition, a gold beryllium (AuBe) alloy pad 216 may be disposed between the indium tin oxide (ITO) layer 211 and the hole supply layer 13 to increase the indium tin oxide (IT〇) layer 211 and the hole supply layer 13 Electrical conductivity. Further, a second metal sound 22 is formed on the surface of the substrate 30 as shown in Fig. 2'. The substrate 30 is a substrate having a thermal conductivity coefficient, and the material of the substrate may be selected from the group consisting of Shi Xi (Si), Ming (A1), copper (Cu), silver (Ag), carbon carbide (SiC), and diamond (diamond). ), graphite, molybdenum, and aluminum nitride. The second metal layer 22 sequentially includes a TiO (Ti) layer 221, a gold (Au) layer 222 and an indium (In) layer 223 on the surface of the substrate 30, wherein the thickness of the indium layer 223 is 〜 4/zm. Referring to FIG. 3, the first metal layer 21' on the surface of the light-emitting diode layer 10 is bonded to the second metal layer 22 on the substrate 30, and the first metal layer 21 and the second metal layer 22 are bonded to each other. A metal bonding layer 2, that is, an indium (In) layer 223 in the second metal layer 22 is bonded to the gold (Au) layer 215 in the first metal layer 21. Therefore, the low adhesion property of the indium (In) layer 223 on the layer 22 of the second metal 200950134 can be adhered to the bonding process of the epitaxial layer 10 of the LED and the substrate 30. The temperature is between 100 ° C and 300 ° C and the bonding pressure is 500 to 5000 lbs. When the bonding temperature is lower than the conventional low temperature of 300 ° C to 900 ° C, the metal bonding layer 20 can be completed at a bonding temperature of between 100 ° C and 300 ° C without affecting the electrical connection. In the case of an effect, the ease of assembly can be increased, and the yield of the metal-adhered crystal grains of the light-emitting diode can be improved. Finally, after the LED epitaxial layer 10 is adhered to the substrate 30 by the metal bonding layer 20, an ohmic contact layer is formed on the electron-emitting layer 11 above the LED epitaxial layer 10. 40. If the metal bonded die of the light emitting diode is completed. The above are only the preferred embodiments of the present invention and are not intended to limit the scope of the present invention. That is, the equivalent changes and modifications made by the scope of the patent application of the present invention are covered by the scope of the invention. 200950134 1 BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic view showing the structure of an epitaxial layer of a light-emitting diode of a low-temperature metal adhesion layer according to the present invention. 2 is a schematic view showing the structure of a substrate for implementing a low temperature metal adhesion layer according to the present invention. Fig. 3 is a schematic view showing the structure of a light-emitting diode of a low temperature metal adhesion layer according to the present invention. [Main component symbol description] 10. Light-emitting diode stray layer 11: Electron supply layer 12: Activation layer '13: Hole supply layer 20: Metal adhesion layer 21: First metal layer 211: Indium tin oxide layer 212: Silver layer 213: Titanium layer 214: Platinum layer 215: Gold layer 216: Gold-bismuth alloy pad 22: Second metal layer 221: Titanium layer 222: Gold layer 223: Indium layer 30: Substrate 200950134 40: Ohmic contact layer
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