請參閱圖1A及圖1B，係顯示本申請案發光元件之一實施例。如圖1A所示，發光元件100包含：一基板結構102；一緩衝層104形成於基板結構102上；一第一半導體層106形成於緩衝層104上；一發光結構108形成於第一半導體層106上；以及一第二半導體層110形成於發光結構108上。第一半導體層106、發光結構108以及第二半導體層110可包含Ⅲ-Ⅴ族元素組成的化合物，例如氮化鋁鎵銦(In
xAl
yGa
1−x−yN，0≦x≦1, 0≦y≦1)系列。發光結構108可包含單異質結構(single heterostructure, SH )，雙異質結構(double heterostructure, DH)，雙側雙異質結構( double-side double heterostructure, DDH)，多層量子井結構(multi-quantum well, MQW)。發光結構108可發出一幅射，於本實施例中，幅射包含光。光可例如為可見光或不可見光。發光結構108具有一厚度方向(T
1)。較佳的，光具有一主發光波長，主發光波長可例如介於250 奈米(nm)至 500 nm之間。於本實施例中，發光元件100更包含一第一電極120以及一第二電極130，第一電極120位於第一半導體層106之上且與第一半導體層106電性連接，第二電極130位於第二半導體層110之上且與第二半導體層110電性連接。
Please refer to FIG. 1A and FIG. 1B , which show an embodiment of the light emitting device of the present application. As shown in Figure 1A, the light-emitting element 100 includes: a substrate structure 102; a buffer layer 104 formed on the substrate structure 102; a first semiconductor layer 106 formed on the buffer layer 104; a light-emitting structure 108 formed on the first semiconductor layer 106 ; and a second semiconductor layer 110 is formed on the light emitting structure 108 . The first semiconductor layer 106, the light emitting structure 108, and the second semiconductor layer 110 may contain compounds composed of III-V elements, such as aluminum gallium indium nitride (In x Al y Ga 1−x−y N, 0≦x≦1 , 0≦y≦1) series. The light emitting structure 108 may include single heterostructure (single heterostructure, SH), double heterostructure (double heterostructure, DH), double-side double heterostructure (double-side double heterostructure, DDH), multi-layer quantum well structure (multi-quantum well, MQW). The light emitting structure 108 can emit a radiation, and in this embodiment, the radiation includes light. The light may, for example, be visible light or invisible light. The light emitting structure 108 has a thickness direction (T 1 ). Preferably, the light has a dominant emission wavelength, and the dominant emission wavelength may be between 250 nanometers (nm) and 500 nm, for example. In this embodiment, the light emitting element 100 further includes a first electrode 120 and a second electrode 130, the first electrode 120 is located on the first semiconductor layer 106 and electrically connected with the first semiconductor layer 106, the second electrode 130 Located on the second semiconductor layer 110 and electrically connected to the second semiconductor layer 110 .
請參閱圖1B並配合參閱圖1A，圖1B係圖1A之基板結構102之一局部放大剖面圖。基板結構102可包含一基底部102b及複數凸出部102c。基底部102b具有一表面102a。於一實施例中，基底部102b的厚度不小於100微米(µm)，較佳的，不大於300 µm。複數凸出部102c以二維陣列方式排列於基底部102b之表面102a上，複數凸出部102c於基底部102b之表面102a上以二維陣列排列方式包含規則或不規則之排列。各凸出部102c包含一第一材料，基底部102b包含一第二材料，第一材料之折射率比第二材料之折射率小。具體地，在主發光波長下，凸出部102c的第一材料之折射率比基底部102b的第二材料之折射率小。較佳的，在主發光波長下，凸出部102c的第一材料之折射率與基底部102b的第二材料之折射率之間的差異大於0.1，較佳的，大於0.15，又更佳的，介於0.15至0.4之間(兩者皆含)。基底部102b之材料可例如為藍寶石(sapphire)，表面102a可為C平面，以適合磊晶成長。各凸出部102c之材料可例如為二氧化矽(SiO
2)。凸出部102c之三維形狀包含錐體，例如圓錐體、多角錐體或截頭式錐體。於本實施例中，凸出部102c之三維形狀為圓錐體，於發光元件之一剖面圖中，凸出部102c之剖面大致呈三角形。緩衝層104可順應地形成在複數凸出部102c與表面102a上。具體地，緩衝層104具有一相反於基底部102b的頂表面1041，頂表面1041包含一第一部位1042以及與第一部位1042連接的第二部位1043，第一部位1042覆蓋之表面102z，第二部位1043覆蓋複數凸出部102c。於發光元件之一剖面圖中，第一部位1042以及第二部位1043之間有一凹槽111。於一實施例中，緩衝層104包含氮化鋁(AlN)材料。緩衝層104的厚度大於5 nm，且較佳的，不超過50 nm，較佳的，緩衝層104的厚度介於 10 nm至30 nm之間(兩者皆含)。於一實施例中，若緩衝層104的厚度小於5 nm，會造成後續成長於其上的磊晶層，例如第一半導體層106的缺陷密度變高，使發光元件的磊晶品質下降。於一實施例中，若緩衝層104，例如AlN緩衝層的厚度超過50 nm，於同一晶圓製造出的複數發光元件之間，會有不均勻的主發光波長。如圖1B所示，其中之一或每一凸出部102c與表面102a間形成一夾角θ，夾角θ之數值不大於65度，較佳的，夾角θ可不大於55度，更佳的，夾角θ介於30度至65度之間(兩者皆含)。於一實施例中，其中之一或每一凸出部102c與表面102a間形成兩個不大於65度之夾角θ，兩夾角θ可皆不大於55度，較佳的，兩夾角θ介於30度至55度之間(兩者皆含)。於一實施例中，其中之一或每一凸出部102c與表面102a間形成之兩個夾角θ之數值相同或不同。各凸出部102c具有一高度H及一底部寬度W。於本實施例中，高度H不大於1.5 µm，較佳的，高度H介於0.5µm至1.5µm之間(兩者皆含)。底部寬度W不小於1µm，較佳的，底部寬度W介於1 µm至 3 µm之間(兩者皆含)。於一實施例中，高度H與底部寬度W的比值可不大於0.5且大於0，較佳的，高度H與底部寬度W的比值介於0.4至0.5之間(兩者皆含)。如圖所示，各凸出部102c可具有一週期P，於一實施例中，於發光元件之一剖面圖中，凸出部102c之剖面具有一頂點，頂點為凸出部102c沿著發光結構108之厚度方向(T
1)最靠近發光結構108之部位。週期P的定義方式為兩相鄰凸出部102c之頂點之間的距離。於本實施例中，於發光元件之一剖面圖中，凸出部102c之剖面大致呈三角形，週期P的定義方式為兩相鄰凸出部102c之頂點之間的距離，週期P介於1µm到3µm之間(兩者皆含)。於一實施例中，於一實施例中，高度H=1.2 ±10%μm；底部寬度W=2.6 ±10%μm；週期P=3.0±10%μm。於又一實施例中，高度H=0.9±10%μm；寬度W=1.6±10%μm；週期P=1.8±10%μm。於又一實施例中，H=1±10%μm；W=1.5±10%μm；P=1.8±10%μm。於又一實施例中，高度H=1.2±10%μm，寬度W=2.6±10%μm；週期P=3.0±10%μm。於一實施例中，使用X-射線繞射分析( X-ray diffraction，XRD)測量發光元件，於(102)面之半高寬(Full width at half maximum，FWHM)小於250 arcsec，較佳的，不小於100 arcsec。藉由複數凸出部102c形成於基板結構102的表面102a上，可有效地反射及散射發光結構108所發出的光線，以增進發光元件100的發光效率，此外，發光元件100藉由本實施例之基板結構102搭配緩衝層104使得後續磊晶形成於其上的半導體層即發光結構具有較佳之磊晶品質。
Please refer to FIG. 1B together with FIG. 1A . FIG. 1B is a partially enlarged cross-sectional view of the substrate structure 102 in FIG. 1A . The substrate structure 102 may include a base portion 102b and a plurality of protruding portions 102c. The base portion 102b has a surface 102a. In one embodiment, the thickness of the base portion 102b is not less than 100 micrometers (µm), preferably not greater than 300 µm. The plurality of protrusions 102c are arranged in a two-dimensional array on the surface 102a of the base portion 102b, and the plurality of protrusions 102c include regular or irregular arrangements in a two-dimensional array on the surface 102a of the base portion 102b. Each protruding portion 102c includes a first material, and the base portion 102b includes a second material, and the refractive index of the first material is smaller than that of the second material. Specifically, at the dominant emission wavelength, the refractive index of the first material of the protruding portion 102c is smaller than that of the second material of the base portion 102b. Preferably, at the dominant emission wavelength, the difference between the refractive index of the first material of the protruding portion 102c and the refractive index of the second material of the base portion 102b is greater than 0.1, preferably greater than 0.15, and more preferably , between 0.15 and 0.4 (both inclusive). The material of the base portion 102b can be, for example, sapphire, and the surface 102a can be a C-plane, which is suitable for epitaxial growth. The material of each protruding portion 102c can be silicon dioxide (SiO 2 ), for example. The three-dimensional shape of the protrusion 102c includes a cone, such as a cone, a polygonal pyramid, or a truncated cone. In this embodiment, the three-dimensional shape of the protruding portion 102c is a cone, and in a cross-sectional view of the light-emitting element, the cross-section of the protruding portion 102c is roughly triangular. The buffer layer 104 can be conformably formed on the plurality of protrusions 102c and the surface 102a. Specifically, the buffer layer 104 has a top surface 1041 opposite to the base portion 102b, the top surface 1041 includes a first portion 1042 and a second portion 1043 connected to the first portion 1042, the surface 102z covered by the first portion 1042, the second The two parts 1043 cover the plurality of protruding parts 102c. In a cross-sectional view of the light emitting element, there is a groove 111 between the first part 1042 and the second part 1043 . In one embodiment, the buffer layer 104 includes aluminum nitride (AlN) material. The thickness of the buffer layer 104 is greater than 5 nm, and preferably not more than 50 nm. Preferably, the thickness of the buffer layer 104 is between 10 nm and 30 nm (both inclusive). In one embodiment, if the thickness of the buffer layer 104 is less than 5 nm, the defect density of the subsequent epitaxial layer grown thereon, such as the first semiconductor layer 106 , will increase, which will degrade the epitaxial quality of the light emitting device. In one embodiment, if the thickness of the buffer layer 104 , such as the AlN buffer layer, exceeds 50 nm, there will be non-uniform dominant emission wavelengths among the plurality of light-emitting devices fabricated on the same wafer. As shown in Figure 1B, one or each of the protrusions 102c forms an included angle θ with the surface 102a, and the value of the included angle θ is not greater than 65 degrees. Preferably, the included angle θ may not be greater than 55 degrees. More preferably, the included angle θ is between 30 degrees and 65 degrees (both inclusive). In one embodiment, two included angles θ not greater than 65 degrees are formed between one or each of the protrusions 102c and the surface 102a, and the two included angles θ may not be greater than 55 degrees. Preferably, the two included angles θ are between Between 30 degrees and 55 degrees (both inclusive). In one embodiment, the values of the two included angles θ formed between one or each of the protrusions 102c and the surface 102a are the same or different. Each protrusion 102c has a height H and a width W at the bottom. In this embodiment, the height H is not greater than 1.5 µm, preferably, the height H is between 0.5 µm and 1.5 µm (both inclusive). The bottom width W is not less than 1 µm, preferably, the bottom width W is between 1 µm and 3 µm (both inclusive). In one embodiment, the ratio of the height H to the bottom width W may be not greater than 0.5 and greater than 0. Preferably, the ratio of the height H to the bottom width W is between 0.4 and 0.5 (both inclusive). As shown in the figure, each protruding portion 102c may have a period P. In one embodiment, in a sectional view of a light-emitting element, the profile of the protruding portion 102c has a vertex, and the vertex is the vertex along which the protruding portion 102c emits light. The thickness direction (T 1 ) of the structure 108 is closest to the part of the light emitting structure 108 . The period P is defined as the distance between the vertices of two adjacent protrusions 102c. In this embodiment, in a cross-sectional view of the light-emitting element, the section of the protrusion 102c is roughly triangular in shape, the period P is defined as the distance between the vertices of two adjacent protrusions 102c, and the period P is between 1 μm to 3µm (both inclusive). In one embodiment, the height H=1.2±10% μm; the bottom width W=2.6±10% μm; the period P=3.0±10% μm. In yet another embodiment, the height H=0.9±10% μm; the width W=1.6±10% μm; the period P=1.8±10% μm. In yet another embodiment, H=1±10% μm; W=1.5±10% μm; P=1.8±10% μm. In yet another embodiment, the height H=1.2±10% μm, the width W=2.6±10% μm; the period P=3.0±10% μm. In one embodiment, X-ray diffraction (X-ray diffraction, XRD) is used to measure the light-emitting element, and the full width at half maximum (FWHM) of the (102) plane is less than 250 arcsec, preferably , not less than 100 arcsec. The plurality of protrusions 102c are formed on the surface 102a of the substrate structure 102, which can effectively reflect and scatter the light emitted by the light emitting structure 108, so as to improve the luminous efficiency of the light emitting element 100. In addition, the light emitting element 100 adopts the present embodiment The combination of the substrate structure 102 and the buffer layer 104 enables the semiconductor layer, ie, the light emitting structure, to be epitaxially formed thereon to have better epitaxial quality.
如圖1A所示，本申請案一實施例揭露之發光元件100之製造方法包含：提供一包含基底部102b及位於其上的複數凸出部102c的基板結構102，其包含提供一基底部102b，其中基底部102b具有一表面102a；以及實施一圖案化步驟，以形成複數凸出部102c。圖案化步驟包含於表面102a上藉由例如為物理氣相沉積(Physical vapor deposition，PVD）之方式形成一前驅層(圖未示)，接著再移除部分的前驅層，移除的方式包含任何合適的方式，例如乾蝕刻或濕蝕刻等方式移除部分的前驅層以形成複數分離的凸出部102c。於本實施例中，於發光元件之一剖面圖中，凸出部102c大致呈三角形。複數凸出部102c以二維陣列方式排列於基底部102b之表面102a上，複數凸出部102c於基底部102b之表面102a上以二維陣列排列方式包含規則或不規則之排列。本申請案一實施例揭露之發光元件100之製造方法更包含形成一緩衝層104於基底部102b之表面102a上且覆蓋複數凸出部102c，緩衝層104包含氮化鋁(AlN)材料。形成一緩衝層104的方法包含物理氣相沉積。於一實施例中，製造發光元件100之方法更包含藉由金屬有機化學氣相沉積((metal-organic chemical vapor deposition，MOCVD)以磊晶成長的方式形第一半導體層106、發光結構108以及第二半導體層110。執行磊晶成長的方式包含但不限於金屬有機化學氣相沉積(metal-organic chemical vapor deposition，MOCVD)、氫化物氣相磊晶法(hydride vapor phase epitaxial，HVPE) 、或是液相晶體外延生長(liquid-phase epitaxy ，LPE)。As shown in FIG. 1A , the manufacturing method of a light-emitting device 100 disclosed in an embodiment of the present application includes: providing a substrate structure 102 including a base portion 102b and a plurality of protrusions 102c thereon, which includes providing a base portion 102b , wherein the base portion 102b has a surface 102a; and a patterning step is performed to form a plurality of protruding portions 102c. The patterning step includes forming a precursor layer (not shown) on the surface 102a by, for example, physical vapor deposition (Physical vapor deposition, PVD), and then removing part of the precursor layer. The removal method includes any A suitable method, such as dry etching or wet etching, removes part of the precursor layer to form a plurality of separated protrusions 102c. In this embodiment, in a cross-sectional view of the light emitting element, the protruding portion 102c is roughly triangular in shape. The plurality of protrusions 102c are arranged in a two-dimensional array on the surface 102a of the base portion 102b, and the plurality of protrusions 102c include regular or irregular arrangements in a two-dimensional array on the surface 102a of the base portion 102b. The manufacturing method of the light-emitting device 100 disclosed in an embodiment of the present application further includes forming a buffer layer 104 on the surface 102a of the base portion 102b and covering the plurality of protrusions 102c. The buffer layer 104 includes aluminum nitride (AlN) material. Methods for forming a buffer layer 104 include physical vapor deposition. In one embodiment, the method for manufacturing the light-emitting device 100 further includes forming the first semiconductor layer 106, the light-emitting structure 108 and The second semiconductor layer 110. The method of performing epitaxial growth includes but not limited to metal-organic chemical vapor deposition (metal-organic chemical vapor deposition, MOCVD), hydride vapor phase epitaxial method (hydride vapor phase epitaxial, HVPE), or It is liquid-phase epitaxy (LPE).
如圖1A所示，於本實施例中，本申請案發光元件更包含一覆蓋層140位於緩衝層104以及第一半導體層106之間。覆蓋層140具有一厚度T，其大於緩衝層104的厚度。較佳的，覆蓋層140包含Ⅲ-Ⅴ族元素組成的化合物，其能階小於緩衝層104之材料的能階。於一實施例中，覆蓋層140包含氮化鎵(GaN)。具體地，覆蓋層140覆蓋緩衝層104，且部分的覆蓋層140位於凹槽111中。覆蓋層140包含一相反於緩衝層104的頂面1401，覆蓋層140的厚度T是指自緩衝層104的頂表面1041的第一部位1042至頂面1401之間的最短距離。較佳的，覆蓋層140的厚度T大於1µm，且較佳的，不超過3.5 µm，又更佳的，介於1至2 µm之間。於一實施例中，覆蓋層140未包含故意摻雜之摻雜物，具體地，覆蓋層140的摻雜物的濃度不大於5×10
17/cm
3，又更佳的，不大於1×10
17/cm
3。本實施例中由於複數凸出部102c形成於基板結構102的表面102a上，且凸出部102c的高度不大於1.5 µm，相較於既有技術之發光元件，本實施例之發光元件可具有較薄之覆蓋層140，但發光元件仍可具有實質上相同的光電性表現，因此可具有體積小的優勢。
As shown in FIG. 1A , in this embodiment, the light emitting device of the present application further includes a covering layer 140 located between the buffer layer 104 and the first semiconductor layer 106 . The covering layer 140 has a thickness T which is greater than that of the buffer layer 104 . Preferably, the capping layer 140 includes a compound composed of III-V elements, the energy level of which is lower than that of the material of the buffer layer 104 . In one embodiment, the capping layer 140 includes gallium nitride (GaN). Specifically, the covering layer 140 covers the buffer layer 104 , and part of the covering layer 140 is located in the groove 111 . The cover layer 140 includes a top surface 1401 opposite to the buffer layer 104 . The thickness T of the cover layer 140 refers to the shortest distance from the first portion 1042 of the top surface 1041 of the buffer layer 104 to the top surface 1401 . Preferably, the thickness T of the covering layer 140 is greater than 1 μm, and preferably not more than 3.5 μm, and more preferably, between 1 and 2 μm. In one embodiment, the capping layer 140 does not contain intentionally doped dopants, specifically, the concentration of the dopant in the capping layer 140 is not greater than 5×10 17 /cm 3 , and more preferably, not greater than 1× 10 17 /cm 3 . In this embodiment, since the plurality of protrusions 102c are formed on the surface 102a of the substrate structure 102, and the height of the protrusions 102c is not greater than 1.5 μm, compared with the light emitting device of the prior art, the light emitting device of this embodiment can have Although the cover layer 140 is thinner, the light-emitting element can still have substantially the same photoelectric performance, so it can have the advantage of small volume.
請參閱圖2A及圖2B，係顯示本申請案發光元件之一實施例。如圖2A所示，發光元件200包含：一基板結構202；一緩衝層204形成於基板結構202上；一第一半導體層206形成於緩衝層204上；一發光結構208形成於第一半導體層206上；以及一第二半導體層210形成於發光結構208上。第一半導體層206、發光結構208以及第二半導體層210包含Ⅲ-Ⅴ族元素組成的化合物，例如氮化鋁鎵銦((In
xAl
yGa
1−x−yN，0≦x≦1, 0≦y≦1))系列。發光結構108可包含單異質結構(single heterostructure, SH )，雙異質結構(double heterostructure, DH)，雙側雙異質結構( double-side double heterostructure, DDH)，多層量子井結構(multi-quantum well, MQW)。發光結構208可發出一幅射，於本實施例中，幅射包含光。光可例如為可見光或不可見光。發光結構208具有一厚度方向(T
1)。較佳的，光具有一主發光波長，主發光波長可例如介於250 奈米(nm)至 500 nm之間。於本實施例中，發光元件更包含一第一電極220以及一第二電極230，第一電極220位於第一半導體層206之上且與第一半導體層206電性連接，第二電極230位於第二半導體層210之上且與第二半導體層210電性連接。
Please refer to FIG. 2A and FIG. 2B , which show an embodiment of the light emitting device of the present application. As shown in Figure 2A, the light-emitting element 200 includes: a substrate structure 202; a buffer layer 204 formed on the substrate structure 202; a first semiconductor layer 206 formed on the buffer layer 204; a light-emitting structure 208 formed on the first semiconductor layer 206 ; and a second semiconductor layer 210 is formed on the light emitting structure 208 . The first semiconductor layer 206, the light emitting structure 208, and the second semiconductor layer 210 contain compounds composed of III-V group elements, such as aluminum gallium indium nitride ((In x Al y Ga 1−x−y N, 0≦x≦1 , 0≦y≦1)) series. The light emitting structure 108 may include single heterostructure (single heterostructure, SH), double heterostructure (double heterostructure, DH), double-side double heterostructure (double-side double heterostructure, DDH), multi-layer quantum well structure (multi-quantum well, MQW). The light emitting structure 208 can emit a radiation, and in this embodiment, the radiation includes light. The light may, for example, be visible light or invisible light. The light emitting structure 208 has a thickness direction (T 1 ). Preferably, the light has a dominant emission wavelength, and the dominant emission wavelength may be between 250 nanometers (nm) and 500 nm, for example. In this embodiment, the light emitting element further includes a first electrode 220 and a second electrode 230, the first electrode 220 is located on the first semiconductor layer 206 and electrically connected with the first semiconductor layer 206, the second electrode 230 is located On the second semiconductor layer 210 and electrically connected to the second semiconductor layer 210 .
請參閱圖2B並配合參閱圖2A，圖2B係圖2A之基板結構202之一局部放大剖面圖。基板結構202可包含一基底部202b及複數凸出部202c。基底部202b具有一表面202a。於一實施例中，基底部202b的厚度不小於100微米(µm)，較佳的，不大於300 µm。複數凸出部102c以二維陣列方式排列於基底部202b之表面202a上，複數凸出部202c於基底部202b之表面202a上以二維陣列排列方式包含規則或不規則之排列。於本實施例中，各凸出部202c與基底部102b可一體形成。具體地，各凸出部202c之材料與基底部202b之材料相同。基底部2102a以及各凸出部202c之之材料可例如為藍寶石(sapphire)，表面202a可為C平面，以適合磊晶成長。凸出部202c之三維形狀包含錐體，例如圓錐體、多角錐體或截頭式錐體。於本實施例中，凸出部202c之三維形狀為圓錐體，於發光元件之一剖面圖中，各凸出部202c之剖面大致呈三角形。緩衝層204可順應地形成在複數凸出部202c與表面202a上。具體地，緩衝層204具有一相反於基底部202b的頂表面2041，頂表面2041包含一第一部位2042以及與第一部位2042連接的第二部位2043，第一部位2042覆蓋基底部202b之表面202a，第二部位2043覆蓋複數凸出部202c。於發光元件之一剖面圖中，第一部位2042以及第一部位2042之間有一凹槽211。於一實施例中，緩衝層204包含氮化鋁(AlN)材料。緩衝層204的厚度大於5 nm，且較佳的，不超過50 nm，較佳的，緩衝層204的厚度介於10 nm至30 nm之間(兩者皆含)。於一實施例中，若緩衝層204的厚度小於5 nm，會造成後續成長於其上的磊晶層，例如第一半導體層206的缺陷密度變高，使發光元件的磊晶品質下降。於一實施例中，若緩衝層204，例如AlN緩衝層的厚度超過50 nm，於同一晶圓製造出的複數發光元件之間，會有不均勻的主發光波長。如圖2B所示，其中之一或每一凸出部202c與表面202a間形成一夾角θ，夾角θ不大於65度，較佳的，夾角θ可不大於55度，更佳的，夾角θ介於30度至65度之間。於一實施例中，其中之一或每一凸出部202c與表面202a間形成兩個不大於65度之夾角θ，兩夾角θ可皆不大於55度，較佳的，兩夾角θ介於30度至55度之間(兩者皆含)。於一實施例中，其中之一或每一凸出部202c與表面202a間形成之兩個夾角θ之數值相同或不同。於本實施例中，各凸出部202c具有一高度H及一底部寬度W。於本實施例中，高度H不大於1.5 µm，較佳的，高度H介於0.5µm至1.5µm之間(兩者皆含)。底部寬度W不小於1µm，較佳的，底部寬度W介於1 µm至 3 µm之間(兩者皆含)。於一實施例中，高度H與底部寬度W的比值可不大於0.5且大於0。較佳的，高度H與底部寬度W的比值介於0.4至0.5之間(兩者皆含)。如圖所示，各凸出部可具有一週期P，於發光元件之一剖面圖中，凸出部202c之剖面具有一頂點，週期P的定義方式為兩相鄰凸出部102c之頂點之間的距離，頂點為凸出部202c沿著發光結構108之厚度方向(T
1)最靠近發光結構108之部位。於本實施例中，於發光元件之一剖面圖中，凸出部202c之剖面大致呈三角形，週期P的定義方式為兩相鄰凸出部102c之頂點之間的距離，週期P介於1µm到3µm之間(兩者皆含)。於一實施例中，高度H=1.2±10%μm；底部寬度W=2.6±10%μm；週期P=3.0±10%μm。於又一實施例中，高度H=0.9±10%μm；底部寬度W=1.6±10%μm；週期P=1.8±10%μm。於又一實施例中，高度H=1±10%μm；底部寬度W=1.5±10%μm；週期P=1.8±10%μm。於又一實施例中，高度H=1.2±10%μm，底部寬度W=2.6±10%μm；週期P=3.0±10%μm。於一實施例中，使用X-射線繞射分析( X-ray diffraction，XRD)測量發光元件，於(102)面之半高寬(Full width at half maximum，FWHM)小於250 arcsec，較佳的，不小於100 arcsec。藉由複數凸出部202c形成於基板結構202的表面202a上，可有效地反射及散射發光結構208所發出的光線，以增進發光元件200的發光效率，此外，發光元件200藉由本實施例之基板結構202搭配緩衝層204使得後續磊晶形成於其上的半導體層即發光結構具有較佳之磊晶品質。
Please refer to FIG. 2B together with FIG. 2A . FIG. 2B is a partially enlarged cross-sectional view of the substrate structure 202 in FIG. 2A . The substrate structure 202 may include a base portion 202b and a plurality of protruding portions 202c. The base portion 202b has a surface 202a. In one embodiment, the thickness of the base portion 202b is not less than 100 micrometers (µm), preferably not greater than 300 µm. The plurality of protrusions 102c are arranged in a two-dimensional array on the surface 202a of the base portion 202b, and the plurality of protrusions 202c include regular or irregular arrangements in a two-dimensional array on the surface 202a of the base portion 202b. In this embodiment, each protruding portion 202c and the base portion 102b can be integrally formed. Specifically, the material of each protruding portion 202c is the same as that of the base portion 202b. The material of the base portion 2102a and each protruding portion 202c can be, for example, sapphire, and the surface 202a can be a C-plane, which is suitable for epitaxial growth. The three-dimensional shape of the protrusion 202c includes a cone, such as a cone, a polygonal pyramid, or a truncated cone. In this embodiment, the three-dimensional shape of the protruding portion 202c is a cone, and in a cross-sectional view of the light emitting element, the cross-section of each protruding portion 202c is roughly triangular. The buffer layer 204 can be conformably formed on the plurality of protrusions 202c and the surface 202a. Specifically, the buffer layer 204 has a top surface 2041 opposite to the base portion 202b, the top surface 2041 includes a first portion 2042 and a second portion 2043 connected to the first portion 2042, the first portion 2042 covers the surface of the base portion 202b 202a, the second portion 2043 covers the plurality of protrusions 202c. In a cross-sectional view of the light emitting element, there is a groove 211 between the first portion 2042 and the first portion 2042 . In one embodiment, the buffer layer 204 includes aluminum nitride (AlN) material. The thickness of the buffer layer 204 is greater than 5 nm, and preferably not more than 50 nm. Preferably, the thickness of the buffer layer 204 is between 10 nm and 30 nm (both inclusive). In one embodiment, if the thickness of the buffer layer 204 is less than 5 nm, the defect density of the subsequent epitaxial layer grown thereon, such as the first semiconductor layer 206, will increase, which will degrade the epitaxial quality of the light emitting device. In one embodiment, if the thickness of the buffer layer 204, such as the AlN buffer layer, exceeds 50 nm, there will be non-uniform dominant emission wavelengths among the plurality of light emitting devices fabricated on the same wafer. As shown in Fig. 2B, an included angle θ is formed between one or each protrusion 202c and the surface 202a, and the included angle θ is not greater than 65 degrees, preferably, the included angle θ may not be greater than 55 degrees, more preferably, the included angle θ is between Between 30 degrees and 65 degrees. In one embodiment, one or each of the protrusions 202c and the surface 202a form two included angles θ not greater than 65 degrees, and the two included angles θ may not be greater than 55 degrees. Preferably, the two included angles θ are between Between 30 degrees and 55 degrees (both inclusive). In one embodiment, the values of the two included angles θ formed between one or each of the protrusions 202c and the surface 202a are the same or different. In this embodiment, each protrusion 202c has a height H and a width W at the bottom. In this embodiment, the height H is not greater than 1.5 µm, preferably, the height H is between 0.5 µm and 1.5 µm (both inclusive). The bottom width W is not less than 1 µm, preferably, the bottom width W is between 1 µm and 3 µm (both inclusive). In one embodiment, the ratio of the height H to the bottom width W may be not greater than 0.5 and greater than zero. Preferably, the ratio of the height H to the bottom width W is between 0.4 and 0.5 (both inclusive). As shown in the figure, each protrusion may have a period P. In a sectional view of a light-emitting element, the section of the protrusion 202c has a vertex, and the period P is defined as the distance between the vertices of two adjacent protrusions 102c. The apex is the closest part of the protruding portion 202c to the light emitting structure 108 along the thickness direction (T 1 ) of the light emitting structure 108 . In this embodiment, in a cross-sectional view of the light-emitting element, the section of the protrusion 202c is roughly triangular in shape, and the period P is defined as the distance between the vertices of two adjacent protrusions 102c, and the period P is between 1 μm to 3µm (both inclusive). In one embodiment, the height H=1.2±10% μm; the bottom width W=2.6±10% μm; the period P=3.0±10% μm. In yet another embodiment, the height H=0.9±10% μm; the bottom width W=1.6±10% μm; the period P=1.8±10% μm. In yet another embodiment, the height H=1±10% μm; the bottom width W=1.5±10% μm; the period P=1.8±10% μm. In yet another embodiment, the height H=1.2±10% μm, the bottom width W=2.6±10% μm; the period P=3.0±10% μm. In one embodiment, X-ray diffraction (X-ray diffraction, XRD) is used to measure the light-emitting element, and the full width at half maximum (FWHM) of the (102) plane is less than 250 arcsec, preferably , not less than 100 arcsec. The plurality of protrusions 202c are formed on the surface 202a of the substrate structure 202, which can effectively reflect and scatter the light emitted by the light emitting structure 208, so as to improve the luminous efficiency of the light emitting element 200. In addition, the light emitting element 200 adopts the present embodiment The combination of the substrate structure 202 and the buffer layer 204 enables the semiconductor layer, ie, the light emitting structure, to be epitaxially formed thereon to have better epitaxial quality.
如圖2A所示，本申請案一實施例揭露之發光元件200之製造方法包含：提供一基板結構202，其包含基底部202b及複數凸出部202c，基底部202b具有一表面202a。複數凸出部202c以二維陣列方式排列於基底部202b之表面202a上，複數凸出部202c於基底部202b之表面202a上以二維陣列排列方式包含規則或不規則之排列。形成一緩衝層204於基底部202b之表面202a上且覆蓋些凸出部202c，緩衝層204包含氮化鋁(AlN)材料。於一實施例中，基板結構202之製造方法包含提供一基材(圖未示)，基材具有一上表面，實施一圖案化步驟，圖案化步驟包含自基材的上表面移除部分基材以形成複數彼此基底部202b以及複數位於基底部202b上且彼此分離的凸出部202c，基底部202b具有一表面202a。移除部分基材的方式可包含藉由任何合適的方式，例如乾蝕刻或濕蝕刻等，於本實施例中，於發光元件之一剖面圖中，凸出部202c大致呈三角形。形成一緩衝層204的方法包含物理氣相沉積。於一實施例中，製造發光元件200之方法更包含藉由金屬有機化學氣相沉積((metal-organic chemical vapor deposition，MOCVD)以磊晶成長的方式形第一半導體層206、發光結構208以及第二半導體層210。執行磊晶成長的方式包含但不限於金屬有機化學氣相沉積(metal-organic chemical vapor deposition，MOCVD)、氫化物氣相磊晶法(hydride vapor phase epitaxial，HVPE) 、或是液相晶體外延生長(liquid-phase epitaxy ，LPE)。As shown in FIG. 2A , the manufacturing method of a light-emitting device 200 disclosed in an embodiment of the present application includes: providing a substrate structure 202 including a base portion 202b and a plurality of protruding portions 202c, and the base portion 202b has a surface 202a. The plurality of protrusions 202c are arranged in a two-dimensional array on the surface 202a of the base portion 202b, and the plurality of protrusions 202c include regular or irregular arrangements in a two-dimensional array on the surface 202a of the base portion 202b. A buffer layer 204 is formed on the surface 202a of the base portion 202b and covers the protrusions 202c. The buffer layer 204 includes aluminum nitride (AlN) material. In one embodiment, the manufacturing method of the substrate structure 202 includes providing a substrate (not shown), the substrate has an upper surface, performing a patterning step, the patterning step includes removing part of the substrate from the upper surface of the substrate. material to form a plurality of base portions 202b and a plurality of protrusions 202c located on the base portion 202b and separated from each other. The base portion 202b has a surface 202a. The method of removing part of the substrate may include any suitable method, such as dry etching or wet etching. In this embodiment, in a cross-sectional view of the light emitting device, the protruding portion 202c is roughly triangular. Methods for forming a buffer layer 204 include physical vapor deposition. In one embodiment, the method for manufacturing the light-emitting device 200 further includes forming the first semiconductor layer 206, the light-emitting structure 208 and The second semiconductor layer 210. The method of epitaxial growth includes but not limited to metal-organic chemical vapor deposition (metal-organic chemical vapor deposition, MOCVD), hydride vapor phase epitaxial method (hydride vapor phase epitaxial, HVPE), or It is liquid-phase epitaxy (LPE).
如圖2A所示，於本實施例中，本申請案發光元件更包含一覆蓋層140位於緩衝層204以及第一半導體層206之間。覆蓋層240具有一厚度T，其大於緩衝層204的厚度。較佳的，覆蓋層240包含Ⅲ-Ⅴ族元素組成的化合物，其能階小於緩衝層204之材料的能階。於一實施例中，覆蓋層240包含氮化鎵(GaN)。具體地，覆蓋層240覆蓋緩衝層204，且部分的覆蓋層240位於凹槽211中。覆蓋層240包含一相反於緩衝層204的頂面2401，覆蓋層240的厚度T是指自第一部位2042至頂面2401之間的最短距離。較佳的，覆蓋層240的厚度T大於1µm，且較佳的，不超過3.5 µm，又更佳的，介於1至2 µm之間。於一實施例中，覆蓋層240未包含故意摻雜之摻雜物，具體地，覆蓋層240的摻雜物之濃度小於5×10
17/cm
3，又更佳的，小於1×10
17/cm
3。本實施例中由於複數凸出部202c形成於基板結構202的表面202a上，且凸出部202c的高度H不大於1.5 µm，相較於既有技術之發光元件，本實施例之發光元件可具有較薄之覆蓋層240，但發光元件仍可具有實質上相同的光電性表現，因此具有體積小的優勢。
As shown in FIG. 2A , in this embodiment, the light emitting device of the present application further includes a covering layer 140 located between the buffer layer 204 and the first semiconductor layer 206 . The covering layer 240 has a thickness T which is greater than that of the buffer layer 204 . Preferably, the capping layer 240 includes a compound composed of III-V elements, the energy level of which is smaller than that of the material of the buffer layer 204 . In one embodiment, the capping layer 240 includes gallium nitride (GaN). Specifically, the covering layer 240 covers the buffer layer 204 , and part of the covering layer 240 is located in the groove 211 . The covering layer 240 includes a top surface 2401 opposite to the buffer layer 204 , and the thickness T of the covering layer 240 refers to the shortest distance from the first portion 2042 to the top surface 2401 . Preferably, the thickness T of the covering layer 240 is greater than 1 μm, and preferably not more than 3.5 μm, and more preferably, between 1 and 2 μm. In one embodiment, the capping layer 240 does not contain intentionally doped dopants, specifically, the concentration of the dopant in the capping layer 240 is less than 5×10 17 /cm 3 , and more preferably, less than 1×10 17 /cm 3 . In this embodiment, since the plurality of protrusions 202c are formed on the surface 202a of the substrate structure 202, and the height H of the protrusions 202c is not greater than 1.5 µm, compared with the light emitting device of the prior art, the light emitting device of this embodiment can With a thinner cover layer 240, the light-emitting element can still have substantially the same photoelectric performance, so it has the advantage of small volume.
請參閱圖3A及圖3B，係顯示本申請案發光元件之一實施例。如圖3A所示，發光元件300包含：一基板結構302；一緩衝層304形成於基板結構302上；一第一半導體層306形成於緩衝層304上；一發光結構308形成於第一半導體層306上；以及一第二半導體層310形成於發光結構308上。第一半導體層306、發光結構308以及第二半導體層310之可包含Ⅲ-Ⅴ族元素組成的化合物，例如氮化鋁鎵銦(In
xAl
yGa
1 − x − yN，0≦x≦1, 0≦y≦1)系列。發光結構108可包含單異質結構(single heterostructure, SH )，雙異質結構(double heterostructure, DH)，雙側雙異質結構( double-side double heterostructure, DDH)，多層量子井結構(multi-quantum well, MQW)。發光結構308可發出一幅射，於本實施例中，幅射包含光。發光結構308具有一厚度方向(T
1)。光可例如為可見光或不可見光。較佳的，光具有一主發光波長，主發光波長可例如介於250 奈米(nm)至 500 nm之間。於本實施例中，發光元件更包含一第一電極320以及一第二電極330，第一電極320位於第一半導體層306之上且與第一半導體層306電性連接，第二電極330位於第二半導體層310之上且與第二半導體層310電性連接。
Please refer to FIG. 3A and FIG. 3B , which show an embodiment of the light emitting device of the present application. As shown in Figure 3A, the light-emitting element 300 includes: a substrate structure 302; a buffer layer 304 formed on the substrate structure 302; a first semiconductor layer 306 formed on the buffer layer 304; a light-emitting structure 308 formed on the first semiconductor layer 306 ; and a second semiconductor layer 310 is formed on the light emitting structure 308 . The first semiconductor layer 306, the light emitting structure 308, and the second semiconductor layer 310 may contain compounds composed of III-V elements, such as aluminum gallium indium nitride (In x Al y Ga 1 − x − y N, 0≦x≦ 1, 0≦y≦1) series. The light emitting structure 108 may include single heterostructure (single heterostructure, SH), double heterostructure (double heterostructure, DH), double-side double heterostructure (double-side double heterostructure, DDH), multi-layer quantum well structure (multi-quantum well, MQW). The light emitting structure 308 can emit a radiation, and in this embodiment, the radiation includes light. The light emitting structure 308 has a thickness direction (T 1 ). The light may, for example, be visible light or invisible light. Preferably, the light has a dominant emission wavelength, and the dominant emission wavelength may be between 250 nanometers (nm) and 500 nm, for example. In this embodiment, the light emitting element further includes a first electrode 320 and a second electrode 330, the first electrode 320 is located on the first semiconductor layer 306 and electrically connected with the first semiconductor layer 306, the second electrode 330 is located On the second semiconductor layer 310 and electrically connected to the second semiconductor layer 310 .
請參閱圖3B並配合參閱圖3A，圖3B係圖3A之基板結構302之一局部放大剖面圖。基底部302b具有一表面302a。於一實施例中，基底部302b的厚度不小於100微米(µm)，較佳的，不大於300 µm。複數凸出部302c以二維陣列圖案排列於基底3202a之表面302a上，複數凸出部302c於基底部302b之表面302a上以二維陣列排列方式包含規則或不規則之排列。各凸出部302c可包含一第一部分302d以及一位於第一部分302d上的第二部分302e，第一部分302d一體成形於基底部302b上，第二部分302e形成於第一部分302d上。具體地，第一部分302d的包含第一材料，其與基底部302b的材料相同。於本實施例中，第二部分302e包含第二材料，第二材料與第一部分302d的第一材料不同，第二部分302e的第二材料之折射率係較第一部分302d的第一材料之折射率小。具體地，在主發光波長下，第二部分302e的第二材料之折射率比第一部分302d的第一材料之折射率小。較佳的，在主發光波長下，第二部分302e的第二材料之折射率與第一部分302d的第一材料折射率之間的差異大於0.1，較佳的，大於0.15，又更佳的，介於0.15至0.4之間(兩者皆含)。凸出部302c之三維形狀包含錐體，例如圓錐體、多角錐體或截頭式錐體。於本實施例中，凸出部302c之三維形狀為圓錐體，於發光元件之一剖面圖中，包含第一部分302d與第二部分302e的凸出部302c之剖面係大致呈三角形之形狀。第二部分302e的材料可例如為二氧化矽(Si0
2)。第一部分302d以及基底部302b之材質可包含藍寶石，表面302a可為C平面，以適合磊晶成長。緩衝層304可順應地在複數凸出部302c與表面302a上。於一實施例中，緩衝層304可為氮化鋁(AlN)材料。緩衝層304的厚度大於5 nm，且較佳的，不超過50 nm，較佳的，緩衝層304的厚度介於 10 nm至30 nm之間(兩者皆含)。於一實施例中，若緩衝層304的厚度小於5 nm，會造成後續成長於其上的磊晶層，例如第一半導體層306的缺陷密度變高，使發光元件的磊晶品質下降，進而降低內部量子效率。於一實施例中，若緩衝層304，例如AlN緩衝層的厚度超過50 nm，於同一晶圓製造出的複數發光元件之間，會有不均勻的主發光波長。如圖3B所示，其中之一或每一凸出部302c與表面302a間形成一夾角θ，夾角θ之數值不大於65度，較佳的，夾角θ可不大於55度，更佳的，夾角θ介於30度至65度之間(兩者皆含)。於一實施例中，其中之一或每一凸出部302c與表面302a間形成兩個不大於65度之夾角θ，兩夾角θ可皆不大於55度，較佳的，兩夾角介於30度至55度之間(兩者皆含)。於一實施例中，其中之一或每一凸出部302c與表面302a間形成之兩個夾角θ之數值相同或不同。各凸出部302c具有一高度H及一底部寬度W，高度H與底部寬度W的比值可小於0.5且大於0。其中一或每一凸出部302c之第一部分302d的高度(H
1)約占凸出部302c之高度H的1~30%(兩者皆含)，較佳的，其中一或每一凸出部302c之第一部分302d的高度(H
1)約占凸出部302c之高度H的10%~20%(兩者皆含)。如圖所示，各凸出部302c可具有一週期P，於一實施例中，於發光元件之一剖面圖中，凸出部102c之剖面具有一頂點，頂點為凸出部302c沿著發光結構308之厚度方向(T
1)最靠近發光結構308之部位。週期P的定義方式為兩相鄰凸出部302c之頂點之間的距離。於本實施例中，於發光元件之一剖面圖中，凸出部302c之剖面大致呈三角形，週期P的定義方式為兩相鄰凸出部302c之頂點之間的距離，週期P介於1µm到3µm之間(兩者皆含)。於一實施例中，高度H=1.2±10%μm；底部寬度W=2.6±10%μm；週期P=3.0±10%μm。於又一實施例中，高度H=0.9±10%μm；底部寬度W=1.6±10%μm；週期P=1.8±10%μm。於又一實施例中，高度H=1.2±10%μm，底部寬度W=2.6±10%μm；週期P=3.0±10%μm。於又一實施例中，高度H=1±10%μm；底部寬度W=1.5±10%μm；週期P=1.8±10%μm。於一實施例中，使用X-射線繞射分析( X-ray diffraction，XRD)測量發光元件，於(102)面之半高寬(Full width at half maximum，FWHM)小於250 arcsec，較佳的，不小於100 arcsec。
Please refer to FIG. 3B together with FIG. 3A . FIG. 3B is a partially enlarged cross-sectional view of the substrate structure 302 in FIG. 3A . The base portion 302b has a surface 302a. In one embodiment, the thickness of the base portion 302b is not less than 100 microns (µm), preferably not greater than 300 µm. The plurality of protrusions 302c are arranged in a two-dimensional array on the surface 302a of the base 3202a, and the plurality of protrusions 302c are arranged in a two-dimensional array on the surface 302a of the base 302b, including regular or irregular arrangements. Each protrusion 302c may include a first portion 302d and a second portion 302e located on the first portion 302d, the first portion 302d is integrally formed on the base portion 302b, and the second portion 302e is formed on the first portion 302d. Specifically, the first portion 302d includes a first material that is the same as that of the base portion 302b. In this embodiment, the second part 302e includes a second material, the second material is different from the first material of the first part 302d, and the refractive index of the second material of the second part 302e is higher than that of the first material of the first part 302d The rate is small. Specifically, at the dominant emission wavelength, the refractive index of the second material of the second portion 302e is smaller than the refractive index of the first material of the first portion 302d. Preferably, at the dominant emission wavelength, the difference between the refractive index of the second material of the second portion 302e and the refractive index of the first material of the first portion 302d is greater than 0.1, preferably greater than 0.15, and more preferably, Between 0.15 and 0.4 (both inclusive). The three-dimensional shape of the protrusion 302c includes a cone, such as a cone, a polygonal pyramid, or a truncated cone. In this embodiment, the three-dimensional shape of the protruding portion 302c is a cone. In a cross-sectional view of the light-emitting device, the cross-section of the protruding portion 302c including the first portion 302d and the second portion 302e is roughly triangular in shape. The material of the second portion 302e can be silicon dioxide (Si0 2 ), for example. The material of the first portion 302d and the base portion 302b may include sapphire, and the surface 302a may be a C-plane, which is suitable for epitaxial growth. The buffer layer 304 can be conformably on the plurality of protrusions 302c and the surface 302a. In one embodiment, the buffer layer 304 can be aluminum nitride (AlN) material. The thickness of the buffer layer 304 is greater than 5 nm, and preferably not more than 50 nm. Preferably, the thickness of the buffer layer 304 is between 10 nm and 30 nm (both inclusive). In one embodiment, if the thickness of the buffer layer 304 is less than 5 nm, the defect density of the subsequent epitaxial layer grown thereon, such as the first semiconductor layer 306, will increase, which will degrade the epitaxial quality of the light-emitting element, and further reduce the internal quantum efficiency. In one embodiment, if the thickness of the buffer layer 304 , such as the AlN buffer layer, exceeds 50 nm, there will be non-uniform dominant emission wavelengths among the plurality of light-emitting devices fabricated on the same wafer. As shown in Figure 3B, an angle θ is formed between one or each protrusion 302c and the surface 302a, and the value of the angle θ is not greater than 65 degrees. Preferably, the angle θ may not be greater than 55 degrees. More preferably, the angle θ θ is between 30 degrees and 65 degrees (both inclusive). In one embodiment, one or each of the protrusions 302c and the surface 302a form two included angles θ not greater than 65 degrees, and the two included angles θ may not be greater than 55 degrees. Preferably, the two included angles are between 30 degrees to 55 degrees (both inclusive). In one embodiment, the values of the two included angles θ formed between one or each of the protrusions 302c and the surface 302a are the same or different. Each protrusion 302c has a height H and a bottom width W, and the ratio of the height H to the bottom width W may be less than 0.5 and greater than zero. The height (H 1 ) of the first part 302d of one or each protrusion 302c accounts for about 1-30% (both inclusive) of the height H of the protrusion 302c. Preferably, one or each protrusion The height (H 1 ) of the first portion 302d of the protruding portion 302c accounts for about 10%-20% (both inclusive) of the height H of the protruding portion 302c. As shown in the figure, each protruding portion 302c may have a period P. In one embodiment, in a cross-sectional view of a light-emitting element, the profile of the protruding portion 102c has a vertex, and the vertex is the vertex along which the protruding portion 302c emits light. The thickness direction (T 1 ) of the structure 308 is closest to the part of the light emitting structure 308 . The period P is defined as the distance between the vertices of two adjacent protrusions 302c. In this embodiment, in a cross-sectional view of the light-emitting element, the section of the protrusion 302c is roughly triangular in shape, and the period P is defined as the distance between the vertices of two adjacent protrusions 302c, and the period P is between 1 μm to 3µm (both inclusive). In one embodiment, the height H=1.2±10% μm; the bottom width W=2.6±10% μm; the period P=3.0±10% μm. In yet another embodiment, the height H=0.9±10% μm; the bottom width W=1.6±10% μm; the period P=1.8±10% μm. In yet another embodiment, the height H=1.2±10% μm, the bottom width W=2.6±10% μm; the period P=3.0±10% μm. In yet another embodiment, the height H=1±10% μm; the bottom width W=1.5±10% μm; the period P=1.8±10% μm. In one embodiment, X-ray diffraction (X-ray diffraction, XRD) is used to measure the light-emitting element, and the full width at half maximum (FWHM) of the (102) plane is less than 250 arcsec, preferably , not less than 100 arcsec.
如圖3A所示，本申請案一實施例揭露之發光元件300之製造方法包含：提供一包含基底部302b及複數凸出部302c的基板結構302，其包含提供一基材(圖未示)，其中基材具有一上表面(圖未示)；以及實施一圖案化步驟，以形成基底部302b以及複數位於基底部302b上且彼此分離的凸出部302c。圖案化步驟包含於基材的上表面上藉由例如為物理氣相沉積(Physical vapor deposition，PVD）之方式形成一前驅層(圖未示)，接著再移除部分的前驅層以及自基材的上表面移除部分的基材，移除的方式包含任何合適的方式，例如乾蝕刻或濕蝕刻等方式移除部分的前驅層以及移除部分的基材，以形成複數分離的凸出部302c及形成基底部302b，基底部302包含表面302a。於本實施例中，於發光元件之一剖面圖中，凸出部302c大致呈三角形。複數凸出部302c以二維陣列方式排列於基底部302b之表面302a上，複數凸出部302c於基底部302b之表面302a上以二維陣列排列方式包含規則或不規則之排列。本申請案一實施例揭露之發光元件300之製造方法更包含形成一緩衝層304於基底部302b之表面302a上且覆蓋複數凸出部302c，緩衝層304包含氮化鋁(AlN)材料。形成緩衝層304的方法包含物理氣相沉積。於一實施例中，製造發光元件300之方法更包含藉由金屬有機化學氣相沉積((metal-organic chemical vapor deposition，MOCVD)以磊晶成長的方式形第一半導體層306、發光結構308以及第二半導體層310。執行磊晶成長的方式包含但不限於金屬有機化學氣相沉積(metal-organic chemical vapor deposition，MOCVD)、氫化物氣相磊晶法(hydride vapor phase epitaxial，HVPE) 、或是液相晶體外延生長(liquid-phase epitaxy ，LPE)。As shown in FIG. 3A , the manufacturing method of the light-emitting device 300 disclosed in an embodiment of the present application includes: providing a substrate structure 302 including a base portion 302b and a plurality of protruding portions 302c, which includes providing a substrate (not shown in the figure) , wherein the substrate has an upper surface (not shown); and a patterning step is performed to form a base portion 302b and a plurality of protrusions 302c located on the base portion 302b and separated from each other. The patterning step includes forming a precursor layer (not shown) on the upper surface of the substrate by means of, for example, physical vapor deposition (Physical vapor deposition, PVD), and then removing part of the precursor layer and from the substrate. Part of the substrate is removed from the upper surface of the upper surface, and the removal method includes any suitable method, such as dry etching or wet etching, to remove part of the precursor layer and remove part of the substrate, so as to form a plurality of separated protrusions 302c and form a base portion 302b that includes a surface 302a. In this embodiment, in a cross-sectional view of the light emitting element, the protruding portion 302c is roughly triangular in shape. The plurality of protrusions 302c are arranged in a two-dimensional array on the surface 302a of the base portion 302b, and the plurality of protrusions 302c are arranged in a two-dimensional array on the surface 302a of the base portion 302b, including regular or irregular arrangements. The manufacturing method of the light-emitting device 300 disclosed in an embodiment of the present application further includes forming a buffer layer 304 on the surface 302a of the base portion 302b and covering the plurality of protrusions 302c. The buffer layer 304 includes aluminum nitride (AlN) material. The method of forming the buffer layer 304 includes physical vapor deposition. In one embodiment, the method for manufacturing the light-emitting device 300 further includes forming the first semiconductor layer 306, the light-emitting structure 308 and the The second semiconductor layer 310. The method of performing epitaxial growth includes but not limited to metal-organic chemical vapor deposition (metal-organic chemical vapor deposition, MOCVD), hydride vapor phase epitaxial method (hydride vapor phase epitaxial, HVPE), or It is liquid-phase epitaxy (LPE).
如圖3A所示，於本實施例中，本申請案發光元件更包含一覆蓋層340位於緩衝層304以及第一半導體層306之間。覆蓋層340具有一厚度T，其大於緩衝層304的厚度。較佳的，覆蓋層340包含Ⅲ-Ⅴ族元素組成的化合物，其能階小於緩衝層204之材料的能階。於一實施例中，覆蓋層340包含氮化鎵(GaN)。具體地，覆蓋層340覆蓋緩衝層304，且部分的覆蓋層340位於凹槽311中。覆蓋層340包含一相反於緩衝層304的頂面3401，覆蓋層340的厚度T是指第一部位3042至頂面3401之間的最短距離。較佳的，覆蓋層340的厚度T大於1µm，且較佳的，不超過3.5 µm，又更佳的，介於1至2 µm之間。於一實施例中，覆蓋層340未包含故意摻雜之摻雜物，具體地，覆蓋層340的摻雜物之濃度小於5×10
17/cm
3，又更佳的，小於1×10
17/cm
3。本實施例中由於複數凸出部302c形成於基板結構202的表面302a上，且凸出部302c的高度H不大於1.5 µm，相較於既有技術之發光元件，本實施例之發光元件可具有較薄之覆蓋層340，但發光元件仍可具有實質上相同的光電性表現，因此具有體積小的優勢。可具有體積小的優勢。
As shown in FIG. 3A , in this embodiment, the light-emitting device of the present application further includes a covering layer 340 located between the buffer layer 304 and the first semiconductor layer 306 . The covering layer 340 has a thickness T which is greater than that of the buffer layer 304 . Preferably, the capping layer 340 includes a compound composed of III-V elements, the energy level of which is lower than that of the material of the buffer layer 204 . In one embodiment, the capping layer 340 includes gallium nitride (GaN). Specifically, the covering layer 340 covers the buffer layer 304 , and part of the covering layer 340 is located in the groove 311 . The covering layer 340 includes a top surface 3401 opposite to the buffer layer 304 , and the thickness T of the covering layer 340 refers to the shortest distance between the first portion 3042 and the top surface 3401 . Preferably, the thickness T of the cover layer 340 is greater than 1 μm, and preferably not more than 3.5 μm, and more preferably, between 1 and 2 μm. In one embodiment, the capping layer 340 does not contain intentionally doped dopants, specifically, the concentration of the dopant in the capping layer 340 is less than 5×10 17 /cm 3 , and more preferably, less than 1×10 17 /cm 3 . In this embodiment, since the plurality of protrusions 302c are formed on the surface 302a of the substrate structure 202, and the height H of the protrusions 302c is not greater than 1.5 μm, compared with the light emitting device of the prior art, the light emitting device of this embodiment can With a thinner cover layer 340, the light-emitting element can still have substantially the same photoelectric performance, so it has the advantage of small size. May have the advantage of small size.
請參閱圖4A及圖4B，係顯示本申請案發光元件之基板結構102之不同態樣實施例之俯視圖。如圖4A所示，基板結構102之基底部102b之表面102a上，有複數個於俯視下外輪廓呈現圓形之凸出部102c，而複數凸出部102c可呈六方最密排列。如圖4B所示，基板結構102之基底部102b之表面102a上，可形成有於俯視下外輪廓大致呈現三角形之複數凸出部102c，而每一三角形的邊可具有弧度，而複數凸出部102c可呈六方最密排列。Please refer to FIG. 4A and FIG. 4B , which are top views showing different embodiments of the substrate structure 102 of the light-emitting device of the present application. As shown in FIG. 4A , on the surface 102a of the base portion 102b of the substrate structure 102, there are a plurality of protruding portions 102c whose outer contours are circular in plan view, and the plurality of protruding portions 102c can be arranged in a hexagonal closest arrangement. As shown in FIG. 4B , on the surface 102a of the base portion 102b of the substrate structure 102, a plurality of protruding portions 102c may be formed with a triangular outer contour in plan view, and the sides of each triangle may have radians, and the plurality of protruding portions may The parts 102c may be arranged in a hexagonal closest arrangement.
請參閱圖5A及圖5B，係顯示本申請案發光元件之基板結構102之凸出部102c的剖面形狀。如圖5A所示，由剖面觀之，凸出部102c可大致呈梯形。具體地，凸出部102c具有一上平面P1以及一與上平面P1相反的下平面P2，相較於上平面P1，下平面P2較接近基底部102b之表面102a。較佳的，上平面P1與下平面P2的比例不大於0.3，且大於0。於一實施例中，搭配圖4B及圖5A觀之，凸出部102c為一截頭式三角錐體，由俯視觀之，下平面P2之三角形外輪廓包圍上平面P1之三角形輪廓，下平面P2之三角形各邊與上平面P1之三角形之各邊之間分別構成一斜面。於本實施例中，週期P的定義方式為兩相鄰凸出部102c之上平面P1中心之間的距離。Please refer to FIG. 5A and FIG. 5B , which show the cross-sectional shape of the protruding portion 102c of the substrate structure 102 of the light-emitting device of the present application. As shown in FIG. 5A , viewed from the cross section, the protruding portion 102c may be roughly trapezoidal. Specifically, the protruding portion 102c has an upper plane P1 and a lower plane P2 opposite to the upper plane P1. Compared with the upper plane P1, the lower plane P2 is closer to the surface 102a of the base portion 102b. Preferably, the ratio of the upper plane P1 to the lower plane P2 is not greater than 0.3 and greater than zero. In one embodiment, with reference to FIG. 4B and FIG. 5A , the protruding portion 102c is a truncated triangular pyramid. From a top view, the triangular outer contour of the lower plane P2 surrounds the triangular contour of the upper plane P1, and the lower plane A slope is formed between each side of the triangle of P2 and each side of the triangle of the upper plane P1. In this embodiment, the period P is defined as the distance between the centers of the plane P1 on two adjacent protrusions 102c.
如圖5B所示，由剖面觀之，凸出部102c包含一向外突起的弧部1021，弧部兩端點連接構成一虛擬之弦部1022。凸出部102c包含一頂部201與弧部1021連接。在本實施例中，弧部1021與弦部1022間的最大距離B可大於0 μm，較佳的，不大於0.5 μm。凸出部102c的頂部201寬度D1為凸出部102c之頂部圓周上任意兩點間的最大距離。於一實施例中，頂部201的寬度D1可為0。於一實施例中，頂部201寬度D1需大於0。夾角θ係介於表面102a與弦部1022間的夾角。於本實施例中，高度H不大於1.5 μm，且大於0 μm。As shown in FIG. 5B , viewed from the cross section, the protruding portion 102c includes an outwardly protruding arc portion 1021 , and two ends of the arc portion are connected to form a virtual chord portion 1022 . The protruding portion 102c includes a top portion 201 connected to the arc portion 1021 . In this embodiment, the maximum distance B between the arc portion 1021 and the chord portion 1022 may be greater than 0 μm, preferably not greater than 0.5 μm. The width D1 of the top 201 of the protrusion 102c is the maximum distance between any two points on the circumference of the top of the protrusion 102c. In one embodiment, the width D1 of the top 201 may be zero. In one embodiment, the width D1 of the top 201 needs to be greater than zero. The included angle θ is the included angle between the surface 102 a and the chord portion 1022 . In this embodiment, the height H is not greater than 1.5 μm and greater than 0 μm.
惟以上所述者，僅為本申請案之較佳實施例而已，並非用來限定本申請案實施之範圍，舉凡依本申請案申請專利範圍所述之形狀、構造、特徵及精神所為之均等變化與修飾，均應包括於本申請案之申請專利範圍內。However, the above-mentioned ones are only the preferred embodiments of this application, and are not used to limit the scope of implementation of this application. For example, all are equal to the shape, structure, characteristics and spirit described in the patent scope of this application. Changes and modifications should be included in the patent application scope of this application.
