461123 五、發明說明α) 【發明之應用領域】 本發明係關於一種半導體發光元件構裝的方法及其結 構,特別是關於一種半導體發光元件覆晶構裝的‘方法及其 結構。 【發明背景】 近年來半導體發光元件的製造技術發展迅速,其中一 個重大的突破是以氮化鎵(G a N )為基礎的發光元件被成 功的製造,使得以發光元件發出在可見光頻譜中藍光區域 的光線成為可能。一種廣泛被採用的氮化錁發光元件的結 構,是在一藍寶石(sapphire)基板上形成氮化鎵之磊晶 層,在該磊晶層之P型及η型半導體上分別形成有一 p (正 )電極及一 η (負)電極,且該ρ電極與該η電極係朝向同 一面。「第1 A、1 Β圖」繪示該發光元件1的一種朁知的構 裝方法,將該η電極2及該ρ電極3朝上,而該藍寶石基板4 朝下與一承載體5,例如,一導線架,相.結合。然後再以 打線接合(w i r e b ο n d i n g )的方式,用金線9 (直徑約2 5 # m )電性連接該電極2、3與該承載體5之電氣連接端6、 7。最後再用高透明之樹脂(e ρ ο X y ) 8將完成打線接合的 該發光元件1包封(e n c a p s u 1 a t e )起來,以保護該發光元 件1與該承載體5之間的電性及機械連結免於受到外界環境 的破壞。 然而以打線接合的方式對發光元件進行封裝,在發光 元件1之表面上的接合墊(bonding pad) 10直徑至少約 1 0 0 // m。這是因為在打線接合的過程中,該金線9的球形461123 V. Description of the invention α) [Application field of the invention] The present invention relates to a method and a structure for mounting a semiconductor light-emitting element, and more particularly, to a method and a structure for mounting a semiconductor light-emitting element on a chip. [Background of the Invention] In recent years, the manufacturing technology of semiconductor light emitting elements has developed rapidly. One of the major breakthroughs has been the successful manufacture of light emitting elements based on gallium nitride (G a N), so that the light emitting elements emit blue light in the visible light spectrum. Area light becomes possible. A widely used hafnium nitride light-emitting device has a structure in which an epitaxial layer of gallium nitride is formed on a sapphire substrate, and a p (positive ) Electrode and an η (negative) electrode, and the ρ electrode and the η electrode are facing the same plane. "Figures 1A, 1B" shows a known method of mounting the light-emitting element 1. The n-electrode 2 and the p-electrode 3 face upward, and the sapphire substrate 4 faces downward and a carrier 5. For example, a lead frame, combined. Then, the electrodes 2 and 3 are electrically connected to the electrical connection ends 6 and 7 of the carrier 5 with a gold wire 9 (diameter of about 2 5 # m) in a wire bonding manner (w i r e b ο n d i n g). Finally, the light-emitting element 1 that has been wire-bonded is encapsulated (encapsu 1 ate) with a highly transparent resin (e ρ ο X y) 8 to protect the electrical properties between the light-emitting element 1 and the carrier 5 and The mechanical connection is protected from damage by the external environment. However, the light-emitting element is packaged by wire bonding, and the bonding pad 10 on the surface of the light-emitting element 1 has a diameter of at least about 1 0 0 // m. This is because during the wire bonding process, the spherical shape of the gold wire 9
五、發明說明(2) 端點π會被壓扁而 倍。因此以打線接 地,會因為該接合 到阻擋而無法通過 件’也會因多次的 另外’以打線 氣連接端6、7必須 發光元件1之電極2 圈迴路(loop)更 元件不斷朝小型化 點。 為原來金線9直徑的三至四 2仃發光元件的構裝,不可避免 墊1 0 ’ 而使得恭也;#。 0 gp # ^先兀件所產生的光線遭 。即使取後光線以其它出路 反射與吸收而強度大減。 x 式,該承栽體5上的該電 3 i : ί間,且以該金線g連接該 、^、该笔氣連接端6、7, 據相當大的空間。對於目前發光 發展的趨勢來說,也無疑的是一種缺 一種新的發光 一 口此本發明乃為解決上述問題,.而提出 几件構裝的方法與結構。 【發明之目的及概述】 本毛月的主要目的乃為解決打線接合之構裝方式所迭 t的空間浪費以及接合墊對光的阻擋的問冑,而提供一種 ^光70件覆晶構裝的方法與結構。 、,根據本發明所提供的發光元件構裝方法,特別有利於 —光元件的小型化,適用於尺寸以及電極間距極小的發光 %件之構裴。 、根據本發明的一種發光元件覆晶構裝的方法,係將一 ^電極及η電極朝向同一面的半導體發光元件,以直接晶片 ^占合⑼irect Chip Attach ; DCA )的方式,藉由一異向 導電膠(Anisotropic Conductive Adhesive ;ACA)或 461123 __ ————――――— — —: 五、發明說明(3) %— —""_"""—_ 焊料(solder )與一預先形成有適當導線圖案以及接合墊 (b 〇 n d i n g p a d )的承載基哮相結合。可省去打線接入構 裝中金線及接合墊所造成的空間浪費以及接合墊阻擋光線 的問題。前述之發光元件’係為在一透明基板,遙晶成長 而得之發光元件,例如,在藍寶石基板上磊晶成..長而得之 氮化鎵(GaN )系列之發光元件,藉此該發光元件所產生 的光線能穿透該透明基板而取出(EXTRACT I ON )。而前喊 之正、負電極上預先形成經適當設計的金屬凸塊或焊料凸 塊’可使在構裝的過程中該電極之間不易發生短路 (short )。前述之異向性導電膠可以是液態、高黏度液 態或是固體狀。而前述承載基板可為一印刷電路板、陶曼 基板或半導體基板,其材質.可為硬性(A丨n、A 12 〇 、b T、 FR4、FR5、Si 等)或軟性(polyimide 等)。 3 根據本發明的一種發光元件的結構,係將p電極以高 反射率的材質來構成’可更增加發光元件光線取出的效° 率。另外,在p電極及η電極上分別形成金屬凸塊,且該金 屬凸塊係凸出於該發光元件的最高表面,如此有利於在以 異向性導電膠(ACA )電性連接該電極與該承載基板之接 合墊時,不易產生電極之間的短路(sh〇rt )。 而根據本發明的另一種發光元件的結構,係直接在p 電極與η電極上分別形成焊料凸塊,該焊料凸塊彼此在形 狀及尺寸上相近’且對稱於該發光元件的中心。如此有利 於在迴熔(reflow),使該電極與該承載基板之接合墊相 接合的製程中,不易產生電極的短路或是造成該發光元件V. Description of the invention (2) The end point π will be squashed and doubled. Therefore, the grounding with a wire will not pass through the part because it is connected to the barrier. It will also be connected to the terminals 6 and 7 with multiple wires. The electrodes of the light-emitting element 1 must be connected. 2 The loop is constantly being miniaturized. point. For the construction of the original gold wire 9 diameter of three to four 2 仃 light-emitting elements, it is inevitable to pad 1 0 ′ and make Kung Yee #. 0 gp # ^ The light generated by the first element is affected. Even if the light is reflected and absorbed in other ways after taking it, the intensity is greatly reduced. In the form of x, the electricity 3 i: ί on the support 5 is connected with the gold wire g and the gas connection ends 6 and 7 by the gold wire g, which has a relatively large space. For the current development trend of luminescence, there is no doubt that it lacks a new kind of luminescence. The present invention is to solve the above problems, and proposes several methods and structures for construction. [Objective and Summary of the Invention] The main purpose of this month is to solve the problem of the waste of space and the blocking of light by the bonding pads in the construction method of wire bonding. Method and structure. According to the method for constructing a light-emitting element provided by the present invention, it is particularly advantageous for miniaturization of the light element, and is suitable for the structure of light-emitting elements with extremely small size and electrode pitch. According to a method for flip-chip mounting of a light-emitting element according to the present invention, a semiconductor light-emitting element with a ^ electrode and an η electrode facing the same surface is formed by a direct chip ^ occupation (irect Chip Attach; DCA). To conductive adhesive (Anisotropic Conductive Adhesive; ACA) or 461123 __ ———————————— —: 5. Description of the invention (3)% — — " " _ " " " —_ solder ) Is combined with a load-bearing substrate pre-formed with a suitable wire pattern and a bonding pad. It can eliminate the waste of space caused by the gold wires and bonding pads in the wiring access structure and the problem that the bonding pads block light. The aforementioned light-emitting element is a light-emitting element obtained by growing a crystal on a transparent substrate, for example, epitaxially grown on a sapphire substrate. A long-range light-emitting element of gallium nitride (GaN) series, thereby The light generated by the light emitting element can pass through the transparent substrate and be taken out (EXTRACT I ON). In addition, an appropriately designed metal bump or solder bump 'is formed on the positive and negative electrodes in advance, so that short-circuits between the electrodes are unlikely to occur during the assembly process. The aforementioned anisotropic conductive adhesive can be liquid, highly viscous liquid or solid. The aforementioned carrier substrate may be a printed circuit board, a Taumann substrate, or a semiconductor substrate. The material of the carrier substrate may be rigid (A, n, A 12 0, b T, FR4, FR5, Si, etc.) or flexible (polyimide, etc.). 3 According to the structure of a light-emitting element of the present invention, the p-electrode is made of a material with a high reflectance ', which can increase the efficiency of taking out light from the light-emitting element. In addition, metal bumps are formed on the p electrode and the η electrode, respectively, and the metal bumps protrude from the highest surface of the light-emitting element, which is beneficial to electrically connecting the electrode with an anisotropic conductive adhesive (ACA). When the bonding pad of the carrier substrate is used, a short circuit (short) between electrodes is less likely to occur. According to another structure of the light-emitting element of the present invention, solder bumps are directly formed on the p electrode and the η electrode, respectively, and the solder bumps are close in shape and size to each other 'and are symmetrical to the center of the light-emitting element. This is advantageous in the process of reflowing the electrode and the bonding pad of the carrier substrate, so that it is not easy to cause a short circuit of the electrode or cause the light emitting element.
46Π23 〜丨〜__________________________________—_ * 一 _- ,一*. ——.....................一— 五、發明說明(4) 〜...- 的旋轉、翻翹的現象。 為使對本發明的目的、構造特徵及其功能有進—步 了解,茲配合圖示詳細說明如下: 乂、 【實施例詳細說明】 「第2A〜2C圖」繪示根據本發明’使用異向性導電膠 (A C A ) 3 0將一發光元件2 〇與一承載基板4 〇相電性接人二 覆晶構裝方法。 °的 首先,如「第2A圖」所示,提供一發光元件2〇,該發 光元件2 0係為在一透明基板2 1上遙晶成長而得之半導體發 光元件’例如’在一藍寶石(s a p p h i r e )基板上磊晶成長 之氮化鍊(G a N )系列發光元件。該發光元.件的尺寸可小 至數百// m以下。在該磊晶層2 2上形成有一 p電極2 3及一 n 电極2 4 ’該ρ電極2 3及該η電極24係朝向該發光元件之同一 面。較佳上’該電極2 3、2 4上並分別形成有金屬凸塊2 5, 該金屬&塊25的高度係凸出於該發光元件2〇之最高表面, 例如’面出2〜1 〇 〇以m ’其質材,例如可為ν i / a u或 C r / C r C u / C u。且該磊晶層2 2及該p電極2 3之裸露部份可形 成一絕緣層2 6加以被覆,如此可使在構裝的過程中電極 2 3、2 4之間不易發生短路。 然後’如「第2 B圖」所示’提供一承載基板4 0,該承 載基板40預先形成有適當的導線(conductor) 41及接合 墊(bonding pad ) 42。並在該承載基板4〇上塗佈一異向 性導電膠層3 0。該異向性導電膠層3 〇可以印刷或是點膠的 方式塗佈於該承載基板40上的適當位置。46Π23 ~ 丨 ~ __________________________________—_ * One _-, one *. ——........... One— Five. Description of the invention (4) ~ .. .- The phenomenon of rotation and warping. In order to further understand the purpose, structural features, and functions of the present invention, detailed descriptions are given in conjunction with the drawings as follows: 乂, [Detailed description of the embodiment] "Figure 2A ~ 2C" shows the use of the different directions according to the present invention An electrically conductive adhesive (ACA) 30 electrically connects a light-emitting element 20 and a carrier substrate 40 to a flip-chip assembly method. ° First, as shown in FIG. 2A, a light-emitting element 20 is provided. The light-emitting element 20 is a semiconductor light-emitting element 'e.g.,' sapphire) a nitrided chain (G a N) series light-emitting element grown on an epitaxial substrate. The size of the light emitting element can be as small as several hundreds / m. A p-electrode 23 and an n-electrode 2 4 are formed on the epitaxial layer 22, and the p-electrode 23 and the n-electrode 24 face the same surface of the light-emitting element. Preferably, metal bumps 25 are formed on the electrodes 2 3, 2 4 respectively, and the height of the metal & block 25 protrudes from the highest surface of the light-emitting element 20, for example, 'face out 2 ~ 1' 〇〇 As m 'material, for example, ν i / au or C r / C r C u / Cu. In addition, the exposed portions of the epitaxial layer 22 and the p-electrode 23 may be covered with an insulating layer 26, so that short-circuiting between the electrodes 2 3 and 2 4 is difficult to occur during the assembly process. Then, as shown in "Fig. 2B", a carrier substrate 40 is provided, and the carrier substrate 40 is previously formed with appropriate conductors 41 and bonding pads 42. An anisotropic conductive adhesive layer 30 is coated on the carrier substrate 40. The anisotropic conductive adhesive layer 30 can be applied by printing or dispensing on an appropriate position on the carrier substrate 40.
第9頁 46丨丨2 3 五、發明說明(5) ^^〜…一—— — 然後,如「第2C圓」所示 25對準該承載基板之該接合势42,’二凡件之金屬Λ塊 元件20與該承載基板4〇相麼 $ =的壓力將該發光 熱使其硬一e)。由於該異導娜加 子(conductive particies ) 31 严 $ 30 内之導電粒 對應的該接合墊42達成電性連处。電極23、24與相 膠3〇並可保護該電極23、24“金屬凸=電 的破壞,且可降低該發光元件2〇盥兮不又外"%境 系數不匹配所造成的不良效應。〇载基板40因熱膨脹 「第3Α〜3C圖」冑示根據本發明,使用 兀件50與-承載基板60相電性接合的覆^^ %先 首先,如「第3Α圖」所示,提供一發裝^法。 光元件50係為在一透明基板51上石曰成^先&件5〇,該發 ,元件’例如’在-藍寶石基板上蟲晶成長之氮;^發 、(GaN )系列發光元件I該發光元件的尺寸可 以下。在該磊晶層52上形成有一p電極53及_n带 P電極53及該η電極54係朝向該發光元件之同一 =°。狭/該 例如,以電鍍的方式在該ρ電極53及該η電極Η 八=後’ 焊料凸塊55,該焊料凸塊55的高度,例如,約古:=形成 二件5。最高表面約2〜1〇“m。為了避免焊料擴 53、54,較佳i,於該焊料凸塊55形成前,先在該^極 53、54上可預先形成底層金屬層(Under 包亟Page 9 46 丨 丨 2 3 V. Description of the invention (5) ^^ ~ ... One—— Then, as shown in "2C circle" 25, align the bonding potential 42 of the carrier substrate, The pressure of the metal Λ block element 20 and the carrier substrate 40 is equal to the pressure of the luminous heat to make it harder. Since the conductive particies 31 and $ 30 correspond to the conductive particles, the bonding pad 42 is electrically connected. The electrodes 23, 24 and the photoresist 30 can protect the electrodes 23, 24. "Metal bump = electrical damage, and can reduce the adverse effect caused by the mismatch of the light-emitting element 20" and "% environmental factor mismatch." 〇 Carrier substrate 40 "Figures 3A to 3C" due to thermal expansion shows that according to the present invention, the cover 50 electrically connected to the carrier substrate 60 using the element 50 is firstly shown as "Figure 3A" Provide a hair pack ^ method. The light element 50 is a transparent element 51 on a transparent substrate 51. The element "for example" is nitrogen grown on a sapphire substrate by worm crystal growth; a light emitting element (GaN) series light emitting element I The size of the light emitting element can be reduced. A p-electrode 53 and an _n-belt P-electrode 53 and the n-electrode 54 are formed on the epitaxial layer 52 toward the same angle of the light-emitting element. For example, the p-electrode 53 and the n-electrode 电镀 = = after the solder bump 55, and the height of the solder bump 55, for example, about 2: 5 is formed. The highest surface is about 2 ~ 10 ″ m. In order to avoid solder expansion 53,54, preferably i, before the formation of the solder bump 55, a bottom metal layer can be formed on the electrodes 53 and 54 in advance (Under package urgently
Metallurgy ; UBM ) 56。另外,較佳上,盡可 凸塊55的形狀與尺寸做成相似’並對稱於該發光元;:料的Metallurgy; UBM) 56. In addition, preferably, the shape and size of the bump 55 can be made similar 'and symmetrical to the light emitting element;
第10頁 Μ 6 1 1 2 3 一1 — —— —·.. _____ 五、發明說明(6) 中心,且該焊料凸塊55之間至少相隔該焊料凸塊55尺寸一 半的距離。如此,可減少在迴熔(ren〇w )的過程中發光 元件轉動、翻翹以及短路的可能。在該磊晶層52及該p電 極53之裸露部份亦可形成一絕緣層57加以被覆。 • a f 5 ί /弗38圖」所示’提供一承載基板60,該承 載基板6Q預先形成有適當的導線61及接合墊⑽。將光 元件之該焊料凸塊55對準該承載基板之該接合後X ^ 合。再進行—迴炫(ren㈣)製程,使該電極53、== 3亥焊枓f塊55而,相對應的該接合墊62達成電性連結。 接者,如「第3C圖」所示,在該發光元件5〇 *該承載 基板60之間填人底膠7Q,用以保護該電極53、“及 凸塊55不受外界環境的破壞,且降低該發光元件5 =氣 載基板6 0因熱膨脹系數不匹配所造成的不良效應。一 μ 7 奋"為了更增加覆晶構裝後發光元件的光取出=率, 二知例中發光兀件之ρ電極,可選用高反光之材質來 率丄::ΓΛ」繪示一發光元件8°的"電極81係為高反射 所組成’該發光元件δ0所產生之朝下的光9。可被 反先之ρ電極81直接反射出去,因而增加了光的取出 該高反光之ρ電極81亦可如「第5圖」所示, 2 =姆特性(0hmic characteHsties) "2而與,亥發光元件8 〇之磊晶層8 · 件有較好的發光效率。以使该發光兀 以上所述者,僅為本發明其中的較佳實施例而已,並 461123 五、發明說明(7) 非用來限定本發明的實施範圍;即凡依本發明申請專利範 圍所作的均等變化與修飾,皆為本發明專利範圍所涵蓋。 __s議 第12頁Page 10 Μ 6 1 1 2 3 One 1 — —— — · .. _____ V. Description of the Invention (6) Center, and the solder bumps 55 are separated by at least half the size of the solder bump 55. In this way, it is possible to reduce the possibility that the light-emitting element rotates, warps, and short-circuits during remelting (renow). An insulating layer 57 may also be formed on the exposed portions of the epitaxial layer 52 and the p-electrode 53 to cover it. • “a f 5” and “Ev. 38” are provided to provide a carrier substrate 60. The carrier substrate 6Q is previously formed with appropriate wires 61 and bonding pads 适当. Align the solder bump 55 of the optical element with the bonding of the carrier substrate after the bonding. Then perform a ren㈣ process, so that the electrodes 53 and == 3 are welded to the f block 55 and the corresponding bonding pads 62 are electrically connected. Then, as shown in FIG. 3C, a primer 7Q is filled between the light-emitting element 50 * and the carrier substrate 60 to protect the electrodes 53, "and the bump 55 from the external environment. And reduce the light-emitting element 5 = air-borne substrate 60 0 due to the thermal expansion coefficient mismatch caused by the unfavorable effect. One μ 7 Fen " In order to increase the light-emitting element light-emitting rate after the flip-chip structure, the light emission in the two known examples The ρ electrode of the element can be selected with a highly reflective material. ::: ΓΛ "shows a light-emitting element 8 °." The electrode 81 is composed of high reflection. "The light-emitting element δ0 produces downward light 9 . It can be directly reflected by the anti-first ρ electrode 81, so that the extraction of light is increased. The high-reflective ρ electrode 81 can also be shown in "Figure 5", 2 = ohmic characteristics (0hmic characteHsties) " 2 and, The epitaxial layer 8 of the light emitting element 8 has good luminous efficiency. So that the above-mentioned light emission is only the preferred embodiment of the present invention, and 461123 V. Description of the invention (7) It is not used to limit the scope of the present invention; All equal changes and modifications are covered by the patent scope of the present invention. __s Discussion Page 12