1364854 九、發明說明： 【發明所屬之技術領域】 本發明係有關於一種半導體發光元件，尤指關於—種 自我接合磊晶形成半導體發光元件之磊晶層的方法。 【先前技術】 傳統半導體發光元件的製作為標準的矩型外觀，目^ 一般半導體材料與封裝材料的折射率相差甚多，使得全反 射角小，所以半導體發光元件所產生的光到達與空氣的界 ^ 面時’大於臨界角的光將產生全反射回到發光元件晶粒内 部。此外，矩形的四個截面立相平行，光子在交界面離開 半導體的機率變小，讓光子只能在内部全反射直到被吸收 殆盡，使光轉成熱的形式，造成發光效果不佳。 因此，改變光的反射是一個有效提升發光效率的方 法，因此現有的作法是在基板1〇的表面部分形成使發光 區域產生光散射或繞射的凹部11及ώ部12的結構（如第 1圖所示），進而使外部量子效率提高，形成高光取出率之 結構。 _ 但是，該些凹部11及凸部12的結構卻也造成後續磊 晶製程的困難，一般需要適當控制磊晶條件，才可得到平 坦且無孔洞的半導體層，來提高光取出率之目地，然而磊 晶之參數例如溫度、壓力、氣流、五三族比、雜質掺雜等 皆會影響磊晶橫向及側向成長之速率改變。請參閱第2圖 所示，磊晶時磊晶層20會在該些凹部11的底面13及凸 部12上方的平面14開始磊晶，當磊晶層20在凸部12上 的侧向成長速率高於凹部11的侧向成長速率時，常常容 易因為相互擠壓，導致蟲晶廣20完成後有孔洞21的產生 5 1364854BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor light-emitting device, and more particularly to a method for self-bonding epitaxially forming an epitaxial layer of a semiconductor light-emitting device. [Prior Art] Conventional semiconductor light-emitting elements are fabricated in a standard rectangular appearance. The refractive index of the semiconductor material and the packaging material are much different, so that the total reflection angle is small, so that the light generated by the semiconductor light-emitting element reaches the air. When the boundary is larger than the critical angle, the light will be totally reflected back into the interior of the light-emitting element die. In addition, the four sections of the rectangle are parallel, and the probability of photons leaving the semiconductor at the interface becomes small, so that the photons can only be totally reflected inside until they are absorbed, and the light is converted into a hot form, resulting in poor illumination. Therefore, changing the reflection of light is a method for effectively improving the luminous efficiency. Therefore, in the conventional method, the concave portion 11 and the crotch portion 12 which cause light scattering or diffraction of the light-emitting region are formed on the surface portion of the substrate 1 (for example, the first As shown in the figure, the external quantum efficiency is further improved to form a structure with a high light extraction rate. _ However, the structures of the recesses 11 and the protrusions 12 also cause difficulties in the subsequent epitaxial process. Generally, it is necessary to appropriately control the epitaxial conditions to obtain a flat and non-porous semiconductor layer to improve the light extraction rate. However, the parameters of epitaxy such as temperature, pressure, gas flow, ratio of five to three, impurity doping, etc. all affect the rate of lateral and lateral growth of the epitaxial growth. Referring to FIG. 2, the epitaxial layer 20 is epitaxially formed on the bottom surface 13 of the recesses 11 and the plane 14 above the protrusions 12 during epitaxy, and the epitaxial layer 20 grows laterally on the protrusions 12. When the rate is higher than the lateral growth rate of the concave portion 11, it is often easy to squeeze each other, resulting in the generation of the hole 21 after the completion of the insect crystal 20 5 1364854
導體發光元件產生的光 影響發光元件的發光效 (如第3圖所示）。該些孔洞21為半 在内部損失，内部量子效率降低， 率與使用壽命。 【發明内容】 於是為解決上述之缺失’本發明的目的在於提供一 ^自我接合蟲晶的方法，在蟲晶成長時可以避免蠢晶參 數誤差所導致孔洞產生，降低缺陷密度，提高i晶層的 品質’進而提升内部量子效率。 本發明的另—目的在於提供自我接合蠢晶的Μ 層，將該遙晶層應用於發光元#，可避免蟲晶參數誤差 所導致孔洞產生，達到高生產量率的目的，且可提高發 光元件的發光效率與使用壽命》 本發明的方法，係在半導體發光元件的一基板表面 形成複數個使光散射或繞射的凹部及凸部結構後的磊 晶方法，其包括：於該基板表面形成一鈍化層，該鈍化層 的材質包括二氧化矽（Si〇2)，並定義出形成該些凹部的蝕 刻區域；然後對該基板進行蝕刻，於前述蝕刻區域蝕刻出 複數個具有自然晶格的斜面與底面的凹部，及上方為平面 且具有該鈍化層的凸部；以及於前述凹部的底面開始磊晶 遙曰曰層，其中該蠢晶層會先填滿該些凹部，然後再覆蓋 該些凸部且開始自我接合向上磊晶完成該磊晶層結構。 其中該基板係為藍寶石（Sapphire)、碳化梦（sic)、妙 (Si)、砷化鎵(GaAs)和氮化鋁(A1N)基板其中之一。該蟲晶 層的材質為氮化鎵（GaN)、氮化銦鎵(in〇aN)、氮化銘嫁 (AlGaN)、氮化銦鋁鎵(InAlGaN)與磷氮化鎵(GaNP)所組的 族群其中之一。 1364854 其中該些凹部形狀為四邊形、圓形、三角形、星形及 多邊形所組的族群其中之一。該些凹部與凸部的構成邊係 Ο.ΟΙμιη至 ΙΟΟμιη，該些凹部的深度Ο.ΟΙμηι至 ΙΟΟμηι。 本發明進一步在該蝕刻製程可以延長蝕刻時間，於前 述蝕刻區域蝕刻出複數個具有自然晶格斜面與底面的凹 部，直到該些凸部的刳面為尖形，成為複數個尖形凸部， 且該鈍化層被除去；然後於前述凹部的底面開始磊晶該磊 晶層，其中該磊晶層會先填滿該些凹部，然後再覆蓋該些 尖形凸部且開始自我接合向上磊晶完成該磊晶層結構。 本發明的優點在於利用蝕刻基板的技術於基板上 形成具有自然晶格斜面圖案之凹部，再將半導體發光元 件的磊晶層選擇性成長於凹部的底面，形成一種自我接 合蠢晶。本發明在蟲晶成長時可以避免蟲晶參數誤差所 導致孔洞產生，降低缺陷密度，提高磊晶層的品質，進 而提升内部量子效率，可提高發光元件的發光效率與使 用壽命。且本發明因為製程簡單，可降低生產成本，適 合產業大量生產。 【實施方式】 茲有關本發明之詳細内容及技術說明，現以實施例 來作進一步說明，但應暸解的是，該等實施例僅為例示 說明之用，而不應被解釋為本發明實施之限制。 本發明利用蝕刻基板的技術，於半導體發光元件的 基板上形成具有自然晶格斜面圖案之凹部，使發光區域 產生光散射或繞射的凹部及凸部的結構，使外部量子效 率提高，形成高光取出率之結構。 本發明的係在半導體發光元件的一基板100表面形成 1364854 . 複數個使光散射或繞射的凹部110及凸部120結構後的磊 晶方法，請參閱第4圖所示，本發明的方法是在於該基 板100表面形成一鈍化層200，並於該鈍化層200定義出 形成該些凹部110的蝕刻區域。其中該基板1〇〇為藍寶 石（Sapphire)、碳化矽（SiC)、矽（Si)、砷化鎵（GaAs)和氮 化鋁（A1N)基板其中之一，該鈍化層200的材質包括二氧 化矽（Si〇2)。然後對該基板1〇〇進行蝕刻，於前述蝕刻區 域蝕刻出複數個具有自然晶格的斜面150與底面130的凹 部110，及上方為平面140且具有該鈍化層200的凸部 ® 120。其中該些凹部11〇形狀為四邊形、圓形、三角形、 星形及多邊形所組的族群其中之一。該些凹部11〇與凸 部120的構成邊係O.Olpm至ΙΟΟμπι，且該些凹部ii〇 的深度為0.01 μιη至1 ΟΟμιη。 近年來，濕式蝕刻藍寶石基板技術已經被廣為發展 研究’所以蝕刻藍寶石基板已經不再是一項困難工作， 本發明可利用蝕刻如藍寶石基板等基板成具有自然晶 格斜面圖案的凹部11〇。例如可使用濕式蝕刻溶液，硫 • 酸：磷酸=5:2，加熱至溫度約27〇°C，即可蝕刻藍寶石基 板’當該鈍化層200之方向平行藍寶石基板之平邊時， 可以钱刻出對稱的複合接面，此複合接面上的斜面15〇 與底面130的角度約43。；當該鈍化層200的方向垂直 藍寶石基板的平邊時，可以蝕刻出自然晶格斜面，此自 然晶格的斜面150與底面130的角度約32。，以及晶格 斜面的複合面，複合面的斜面15〇與底面130的角度約 60°。 請再參閱第5-1與5-2圖所示，然後再於前述凹部 1364854 110的底面130開始磊晶一磊晶層300(如第5-1圖所示）， 其中，該磊晶層的材質為氮化鎵（GaN)、氮化銦鎵 (InGaN)、IU匕 IS 錄（AlGaN)、IU匕 録（inAlGaN)與 磷氮化鎵（GaNP)所組的族群其中之一。該磊晶層300只 會選擇性成長於凹部110的底面130，並不會成長於钱 刻所形成的斜面150上，也不會成長於凸部120上方的 鈍化層200上方’所以該磊晶層300會先穩定成長填滿該 些凹部110(如第5-2圖所示），然後再覆蓋該些凸部120 且開始自我接合向上蟲晶完成該蠢晶層300結構(如第6 圖所示）。 本發明也可增加對該基板1 〇〇進行姓刻的時間，直 到該純化層200被除去。如第7圖所示，本發明進一步可 延長對基板100的姓刻時間，於前述触刻區域姓刻出複 數個具有自然晶格斜面150與底面130的凹部11〇，而該些 凸部120的剖面成為尖形，成為複數個尖形凸部121，直到 該鈍化層200被除去。然後再於前述凹部11〇的底面13〇開 始蟲晶一蟲晶層300(如第8-1圖所示），該蟲晶層3〇〇只會選 • 擇性成長於凹部11〇的底面130，並不會成長於蝕刻所形成 的斜面150上，也不會成長於該尖形凸部121的上方’所以 該蠢晶層300會先穩定成長填滿該些凹部η〇(如第8—2圖所 示）’然後再覆蓋該些尖形凸部121且開始自我接合向上磊 晶完成該磊晶層300結構(如第9圖所示）。 本發明的自我接合蟲晶技術，在蠢晶成長時可以避免 蟲晶參數誤差所導致孔洞產生，降低缺陷密度，提高磊晶 層的品質’進而提升内部量子效率’可提高發光元件的發 光效率與使用壽命。且本發明因為製程簡單，可降低生產 9 1364854 成本，適合產業大量生產。 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。 1364854 ，【圖式簡單說明】 第1圖，係傳統的基板表面形成凹部與凸部的结構示弋 第2圖，係傳統的基板表面磊晶過程的示意圖。 第3圖’係傳統的基板表面磊晶後的結構示意圖。 =4圖，係本發明的基板表面形成凹部及凸部的結構示 意圖。 第5 1 /、5 2圖，係第4圖的基板表面蟲晶過程的示意 鲁圖。 第6圖，係第4圖的基板表面磊晶後的結構示意圖。 第7圖，係本發明的基板表面形成尖形凸部的結構示意 圖。 第 /、82圖’係第7圖的基板表面蟲晶過程的意 圖。 第®係'第7圖的基板表面蟲晶後的結構示意圖。 【主要元件符號說明】 <習知> ❿ 1〇 :基板 11 :凹部 12 :凸部 13 :底面 14 :平面 20 :蟲晶層 21 :孔洞 <本發明> 100 ·基板 1364854 110 :凹部 120 :凸部 121 :尖形凸部 130 :底面 140 :平面 150 :斜面 200 :鈍化層 300 :磊晶層The light generated by the conductor light-emitting element affects the light-emitting effect of the light-emitting element (as shown in Fig. 3). The holes 21 are half internal loss, internal quantum efficiency is reduced, rate and service life. SUMMARY OF THE INVENTION Therefore, in order to solve the above-mentioned shortcomings, the object of the present invention is to provide a method for self-bonding insect crystals, which can avoid the generation of voids caused by the error of the parasitic crystal parameters, reduce the defect density, and improve the i-layer during the growth of the crystallites. The quality 'and thus the internal quantum efficiency. Another object of the present invention is to provide a self-joining ruthenium layer, which is applied to the illuminating element #, which can avoid the occurrence of voids caused by errors in the crystallite parameters, achieve high throughput rate, and can improve the light-emitting element. Light-emitting efficiency and service life. The method of the present invention is an epitaxial method in which a plurality of concave and convex structures for scattering or diffracting light are formed on a surface of a substrate of a semiconductor light-emitting element, comprising: forming on the surface of the substrate a passivation layer, the passivation layer is made of cerium oxide (Si 〇 2), and defines an etched region forming the recesses; then etching the substrate, etching a plurality of natural crystal lattices in the etched region a concave portion of the inclined surface and the bottom surface, and a convex portion having a flat surface and having the passivation layer; and an epitaxial layer is formed on the bottom surface of the concave portion, wherein the stray layer first fills the concave portions, and then covers the concave portion The protrusions begin to self-join upwardly to complete the epitaxial layer structure. The substrate is one of a sapphire, a sic, a GaAs, and an aluminum nitride (A1N) substrate. The material of the insect layer is gallium nitride (GaN), indium gallium nitride (in〇aN), nitrided (AlGaN), indium aluminum gallium nitride (InAlGaN) and gallium nitride (GaNP). One of the ethnic groups. 1364854 wherein the recesses are one of a group of quadrilaterals, circles, triangles, stars, and polygons. The concave portions and the convex portions are formed by Ο.ΟΙμιη to ΙΟΟμιη, and the depths of the concave portions are Ο.ΟΙηηι to ΙΟΟμηι. Further, in the etching process, the etching time can be extended, and a plurality of concave portions having a natural lattice slope and a bottom surface are etched in the etching region until the convex surfaces of the convex portions are pointed and become a plurality of pointed convex portions. And the passivation layer is removed; then the epitaxial layer is epitaxially formed on the bottom surface of the recess, wherein the epitaxial layer fills the recesses first, then covers the pointed protrusions and begins self-joining upward epitaxy The epitaxial layer structure is completed. An advantage of the present invention is that a recess having a natural lattice bevel pattern is formed on the substrate by a technique of etching the substrate, and the epitaxial layer of the semiconductor light-emitting element is selectively grown on the bottom surface of the recess to form a self-bonding crystal. The invention can avoid the generation of voids caused by the error of the crystal crystal parameters, reduce the defect density, improve the quality of the epitaxial layer, and thereby improve the internal quantum efficiency, and can improve the luminous efficiency and the service life of the light-emitting element. Moreover, the invention can reduce the production cost because of the simple process, and is suitable for mass production in the industry. The embodiments and the technical description of the present invention are further described in the following examples, but it should be understood that the embodiments are merely illustrative and should not be construed as being The limit. According to the technique of etching a substrate, a recess having a natural lattice bevel pattern is formed on a substrate of the semiconductor light emitting element, and a concave portion and a convex portion of the light emitting region are scattered or diffracted, thereby improving external quantum efficiency and forming a highlight. The structure of the take-out rate. In the present invention, a surface of a substrate 100 of a semiconductor light-emitting device is formed by 1364854. The plurality of epitaxial methods for scattering or diffracting the concave portion 110 and the convex portion 120, as shown in FIG. 4, the method of the present invention A passivation layer 200 is formed on the surface of the substrate 100, and an etched region where the recesses 110 are formed is defined in the passivation layer 200. The substrate 1 is one of a sapphire, a tantalum carbide (SiC), a bismuth (Si), a gallium arsenide (GaAs), and an aluminum nitride (A1N) substrate, and the passivation layer 200 is made of a dioxide.矽 (Si〇2). Then, the substrate 1 is etched, and a plurality of recesses 110 having a natural crystal lattice inclined surface 150 and a bottom surface 130 are etched in the etching region, and a convex portion 120 having the planar surface 140 and having the passivation layer 200 is formed. The recesses 11 are shaped into one of a group of quadrilaterals, circles, triangles, stars, and polygons. The concave portions 11〇 and the convex portions 120 are formed by O.Olpm to ΙΟΟμπι, and the recesses ii 〇 have a depth of 0.01 μm to 1 μm. In recent years, wet etching of sapphire substrate technology has been widely studied. Therefore, etching a sapphire substrate is no longer a difficult task. The present invention can utilize a substrate such as a sapphire substrate to form a recess 11 having a natural lattice bevel pattern. . For example, a wet etching solution, sulfur acid: phosphoric acid = 5:2, heated to a temperature of about 27 ° C, can etch the sapphire substrate. When the direction of the passivation layer 200 is parallel to the flat side of the sapphire substrate, A symmetrical composite joint is engraved, and the angle between the slope 15 〇 and the bottom surface 130 of the composite joint is about 43. When the direction of the passivation layer 200 is perpendicular to the flat side of the sapphire substrate, the natural lattice bevel may be etched, and the angle between the slope 150 of the natural crystal lattice and the bottom surface 130 is about 32. And the composite face of the lattice bevel, the angle of the bevel 15〇 of the composite face and the angle of the bottom face 130 is about 60°. Referring to FIGS. 5-1 and 5-2 again, an epitaxial epitaxial layer 300 (shown in FIG. 5-1) is started on the bottom surface 130 of the recess 1364584, wherein the epitaxial layer The material is one of a group of gallium nitride (GaN), indium gallium nitride (InGaN), IU匕IS recording (AlGaN), IU recording (inAlGaN), and gallium phosphorus nitride (GaNP). The epitaxial layer 300 is only selectively grown on the bottom surface 130 of the recess 110, and does not grow on the slope 150 formed by the money, nor does it grow above the passivation layer 200 above the protrusion 120. The layer 300 will first grow stably to fill the recesses 110 (as shown in Figures 5-2), then cover the protrusions 120 and begin self-joining upwards to complete the structure of the stray layer 300 (Fig. 6) Shown). The present invention can also increase the time for the substrate 1 to be surnamed until the purification layer 200 is removed. As shown in FIG. 7, the present invention further extends the time of the substrate 100, and a plurality of recesses 11 having a natural lattice slope 150 and a bottom surface 130 are formed in the aforementioned touch region, and the protrusions 120 are formed. The cross section becomes a pointed shape and becomes a plurality of pointed convex portions 121 until the passivation layer 200 is removed. Then, the worm crystal layer 300 (as shown in FIG. 8-1) is started on the bottom surface 13 of the recess 11 ,, and the worm layer 3 〇〇 is selectively grown on the bottom surface of the recess 11 〇 130, does not grow on the inclined surface 150 formed by etching, and does not grow above the pointed convex portion 121. Therefore, the stray crystal layer 300 first grows stably and fills the concave portions η (such as the eighth Figure 2 shows the structure of the epitaxial layer 300 (as shown in Figure 9). The self-bonding insect crystal technology of the invention can avoid the generation of voids caused by the error of the crystal crystal parameters during the growth of the stray crystal, reduce the defect density, improve the quality of the epitaxial layer 'and thereby improve the internal quantum efficiency', and can improve the luminous efficiency of the light-emitting element and Service life. Moreover, the invention has the advantages of simple process, can reduce the cost of production 9 1364854, and is suitable for mass production in the industry. The above is only the preferred embodiment of the invention, and is not intended to limit the scope of the 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. 1364854, [Simple description of the drawing] Fig. 1 is a schematic view showing the structure of forming a concave portion and a convex portion on a conventional substrate surface. Fig. 2 is a schematic view showing a conventional epitaxial process of a substrate surface. Fig. 3 is a schematic view showing the structure of a conventional substrate after epitaxial polishing. Fig. 4 is a view showing the structure in which the concave portion and the convex portion are formed on the surface of the substrate of the present invention. Fig. 5 1 /, 5 2 is a schematic diagram of the surface crystallographic process of the substrate in Fig. 4. Fig. 6 is a schematic view showing the structure after the substrate surface is epitaxial in Fig. 4. Fig. 7 is a view showing the structure of forming a pointed convex portion on the surface of the substrate of the present invention. Fig. 4 and Fig. 82 are diagrams showing the surface crystallographic process of the substrate in Fig. 7. Schematic diagram of the surface of the substrate on the surface of the substrate of Figure 7 of Figure 7. [Explanation of main component symbols] <General knowledge> ❿ 1〇: Substrate 11: concave portion 12: convex portion 13: bottom surface 14: plane 20: worm layer 21: hole <present invention> 100 · substrate 1364854 110: Concave portion 120: convex portion 121: pointed convex portion 130: bottom surface 140: plane 150: inclined surface 200: passivation layer 300: epitaxial layer