本揭露之各實施例詳細描述如下,並且繪製於圖式。本揭露之各實施例可配合對應之圖式一併理解,圖式亦視為本揭露之各實施例說明的一部分。需了解的是,為了清楚呈現本揭露之各實施例的特徵,圖式並未以構件之實際比例繪示。Various embodiments of the present disclosure are described in detail below and illustrated in the accompanying drawings. The various embodiments of the present disclosure can be understood together with the corresponding drawings, and the drawings are also regarded as a part of the description of the various embodiments of the present disclosure. It should be understood that, in order to clearly present the features of the various embodiments of the present disclosure, the drawings are not drawn in actual proportions of components.
第1圖顯示符合本揭露之半導體發光元件之第一實施例。半導體發光元件10包含基板100、布拉格反射結構101、半導體發光疊層102、第一電極103、以及第二電極104。半導體發光疊層102位於基板100之上表面並依序包含第一導電型半導體接觸層102a、第一導電型半導體限制層(confinement layer)102b、主動結構102c、第二導電型半導體限制層(confinement layer)102d、以及第二導電型半導體接觸層102e。第一導電型半導體限制層102b及第二導電型半導體限制層102d用以侷限載子(電子及電洞)於主動結構102c內以避免載子溢流出主動結構102c而降低發光效率,第一導電型半導體限制層102b及第二導電型半導體限制層102d各具有一能隙大於主動結構102c之能隙。第一導電型半導體接觸層102a具有一摻雜濃度大於第一導電型半導體限制層102b之摻雜濃度。第一電極103位於第一導電型半導體接觸層102a之上並與第一導電型半導體接觸層102a形成良好的電性接觸,例如歐姆接觸。第二導電型半導體接觸層102e具有一摻雜濃度大於第二導電型半導體限制層102d之摻雜濃度。第二電極104位於第二導電型半導體接觸層102e之上並與第二導電型半導體接觸層102e形成良好的電性接觸,例如歐姆接觸。主動結構102c例如包含多重量子井(Multiple Quantum Wells; MQW)結構,並於驅動時發出具有一峰波長(peak wavelength)為λ nm之可見光或不可見光。第一導電型例如為n型且第二導電型例如為p型。FIG. 1 shows a first embodiment of a semiconductor light emitting device according to the present disclosure. The semiconductor light emitting device 10 includes a substrate 100 , a Bragg reflective structure 101 , a semiconductor light emitting stack 102 , a first electrode 103 , and a second electrode 104 . The semiconductor light emitting stack 102 is located on the upper surface of the substrate 100 and sequentially includes a first conductivity type semiconductor contact layer 102a, a first conductivity type semiconductor confinement layer 102b, an active structure 102c, a second conductivity type semiconductor confinement layer (confinement layer) layer) 102d, and the second conductivity type semiconductor contact layer 102e. The first conductivity type semiconductor confinement layer 102b and the second conductivity type semiconductor confinement layer 102d are used to confine carriers (electrons and holes) in the active structure 102c to prevent carriers from overflowing the active structure 102c and reduce the luminous efficiency. The semiconductor confinement layer 102b of the first conductivity type and the semiconductor confinement layer 102d of the second conductivity type each have an energy gap larger than that of the active structure 102c. The first conductivity type semiconductor contact layer 102a has a doping concentration greater than that of the first conductivity type semiconductor confinement layer 102b. The first electrode 103 is located on the first conductive type semiconductor contact layer 102a and forms a good electrical contact with the first conductive type semiconductor contact layer 102a, such as an ohmic contact. The second conductivity type semiconductor contact layer 102e has a doping concentration greater than that of the second conductivity type semiconductor confinement layer 102d. The second electrode 104 is located on the second conductivity type semiconductor contact layer 102e and forms a good electrical contact with the second conductivity type semiconductor contact layer 102e, such as an ohmic contact. The active structure 102c includes, for example, a multiple quantum well (Multiple Quantum Wells; MQW) structure, and emits visible light or invisible light with a peak wavelength (peak wavelength) of λ nm when driven. The first conductivity type is, for example, n-type and the second conductivity type is, for example, p-type.
布拉格反射結構101位於基板100之下表面用以反射主動結構102c發出之光。布拉格反射結構101包含複數介電層對,其中,每一介電層對分別包含第一介電層101a及第二介電層101b,第一介電層101a具有第一幾何厚度(geometrical thickness)GT1、第一光學厚度(optical thickness)OT1、及第一折射率n1,第二介電層101b具有第二幾何厚度GT2、第二光學厚度OT2及第二折射率n2,第一光學厚度OT1及第二光學厚度OT2其中之一小於0.25kλ nm且第一光學厚度OT1及第二光學厚度OT2其中之另一個大於0.25kλ nm,k為正奇數,例如1、3、 5 或 7。於本實施例中,第一折射率n1大於第二折射率n2,例如,第一折射率n1介於1.7至3之間且第二折射率n2介於1.2至1.7之間;基板100例如包含藍寶石,第一介電層101a例如包含氧化鈦(TiO
x)、氧化鈮(NbO
x)或氧化鉭(TaO
x)等,第二介電層101b例如包含氧化矽(SiO
x)、氧化鋁(AlO
x)或氟化鎂(MgF
x)等。於另一實施例中,第一折射率n1小於第二折射率n2,例如第一折射率n1大於或等於1.2且小於1.7,第二折射率n2大於或等於1.7且小於或等於3;基板100例如包含藍寶石,第一介電層101a例如包含氧化矽(SiO
x)、氧化鋁(AlO
x)或氟化鎂(MgF
x)等,第二介電層101b例如包含氧化鈦(TiO
x)、氧化鈮(NbO
x)或氧化鉭(TaO
x)等。於一實施例中,所述之複數介電層對之對數大於3對,例如4~20對。基板100之折射率例如介於第一折射率n1與第二折射率n2之間。其中,於本揭露所述之光學厚度定義為所述之介電層之幾何厚度與其折射率的乘積,例如第一介電層101a之第一光學厚度OT1為其幾何厚度GT1與其第一折射率n1之乘積。本實施例之基板100位於布拉格反射結構101及半導體發光疊層102之間,因此,半導體發光疊層102向下發出之光線穿透基板100且被布拉格反射結構101反射回基板100而自半導體發光疊層102之表面及基板100之側面摘出,其中,布拉格反射結構101對主動結構102c所發出之光具有至少70%之反射率。
The Bragg reflection structure 101 is located on the lower surface of the substrate 100 to reflect the light emitted by the active structure 102c. The Bragg reflection structure 101 includes a plurality of dielectric layer pairs, wherein each pair of dielectric layers includes a first dielectric layer 101a and a second dielectric layer 101b, and the first dielectric layer 101a has a first geometrical thickness. GT1, a first optical thickness (optical thickness) OT1, and a first refractive index n1, the second dielectric layer 101b has a second geometric thickness GT2, a second optical thickness OT2, and a second refractive index n2, the first optical thickness OT1 and One of the second optical thickness OT2 is less than 0.25kλ nm and the other of the first optical thickness OT1 and the second optical thickness OT2 is greater than 0.25kλ nm, k is a positive odd number, such as 1, 3, 5 or 7. In this embodiment, the first refractive index n1 is greater than the second refractive index n2, for example, the first refractive index n1 is between 1.7 and 3 and the second refractive index n2 is between 1.2 and 1.7; the substrate 100 includes, for example For sapphire, the first dielectric layer 101a includes, for example, titanium oxide (TiO x ), niobium oxide (NbO x ), or tantalum oxide (TaO x ), and the second dielectric layer 101b, for example, includes silicon oxide (SiO x ), aluminum oxide ( AlO x ) or magnesium fluoride (MgF x ), etc. In another embodiment, the first refractive index n1 is smaller than the second refractive index n2, for example, the first refractive index n1 is greater than or equal to 1.2 and less than 1.7, and the second refractive index n2 is greater than or equal to 1.7 and less than or equal to 3; the substrate 100 For example, it includes sapphire, the first dielectric layer 101a includes, for example, silicon oxide (SiO x ), aluminum oxide (AlO x ), or magnesium fluoride (MgF x ), etc., and the second dielectric layer 101b includes, for example, titanium oxide (TiO x ), Niobium oxide (NbO x ) or tantalum oxide (TaO x ), etc. In one embodiment, the number of pairs of the plurality of dielectric layers is greater than 3 pairs, for example, 4-20 pairs. The refractive index of the substrate 100 is, for example, between the first refractive index n1 and the second refractive index n2. Wherein, the optical thickness described in this disclosure is defined as the product of the geometric thickness of the dielectric layer and its refractive index, for example, the first optical thickness OT1 of the first dielectric layer 101a is its geometric thickness GT1 and its first refractive index The product of n1. The substrate 100 of this embodiment is located between the Bragg reflective structure 101 and the semiconductor light emitting stack 102. Therefore, the light emitted downward by the semiconductor light emitting stack 102 penetrates the substrate 100 and is reflected back to the substrate 100 by the Bragg reflective structure 101 to emit light from the semiconductor. The surface of the stack 102 and the side surface of the substrate 100 are extracted, wherein the Bragg reflection structure 101 has a reflectivity of at least 70% for the light emitted by the active structure 102c.
第2圖顯示如前述實施例所揭示之布拉格反射結構101之第一例示。如第2圖所示,布拉格反射結構101係包含12對之介電層對,並依堆疊順序包含層數為第1、2、3、4…23及24層,其中,層數為第1、3、5、7… 23層係為第一介電層101a,層數為第2、4、6、8…24 層係為第二介電層101b,相鄰之第一介電層101a及第二介電層101b係組成一介電層對,其中,第一介電層101a之第一折射率n1大於第二介電層101b之第二折射率n2;於一介電層對中,第一介電層101a較第二介電層101b更靠近基板100。於本實施例,第一介電層101a之第一光學厚度OT1係小於0.25kλ nm,例如為0.2kλ nm;以k=1為例,(第一光學厚度OT1/λ)為0.2,如第2圖所示。於本實施例,第二介電層101b之第二光學厚度OT2係大於0.25kλ nm,例如為0.3kλ nm;以k=1為例,(第二光學厚度OT2/λ)為0.3,如第2圖所示。於一實施例,第一光學厚度大於0.15kλ且小於0.25kλ nm且第二光學厚度大於0.25kλ且小於0.35kλ nm。符合上述光學厚度之大小關係的介電層對為連續重複3對以上。於一實施例,布拉格反射結構101之每一介電層對之第一光學厚度OP1及第二光學厚度OP2之總和為(0.5±0.05) kλ nm。於一實施例,於布拉格反射結構101中,第1層係最靠近基板100且第24層係最遠離基板100。於一實施例,第1層與基板100直接接觸。於另一實施例中,第1層與基板100之間選擇性地設有一窗戶層(window layer)(圖未示),窗戶層對於主動結構所發出的光線為透明,以增加半導體發光元件10的光摘出。窗戶層之厚度大於第一介電層101a的厚度及第二介電層101b的厚度,例如約介於300 nm與1000 nm,其材料不同於布拉格反射結構101之第1層之材料以及不同於基板100之材料。FIG. 2 shows a first example of the Bragg reflection structure 101 disclosed in the previous embodiments. As shown in FIG. 2, the Bragg reflective structure 101 includes 12 pairs of dielectric layers, and includes layers 1, 2, 3, 4...23 and 24 in stacking order, wherein the number of layers is 1 , 3, 5, 7... 23 layers are the first dielectric layer 101a, the number of layers is the 2nd, 4, 6, 8... 24 layers are the second dielectric layer 101b, and the adjacent first dielectric layer 101a And the second dielectric layer 101b constitutes a dielectric layer pair, wherein, the first refractive index n1 of the first dielectric layer 101a is greater than the second refractive index n2 of the second dielectric layer 101b; in a dielectric layer pair , the first dielectric layer 101a is closer to the substrate 100 than the second dielectric layer 101b. In this embodiment, the first optical thickness OT1 of the first dielectric layer 101a is less than 0.25kλ nm, such as 0.2kλ nm; taking k=1 as an example, (the first optical thickness OT1/λ) is 0.2, as shown in the first 2 as shown in Fig. In this embodiment, the second optical thickness OT2 of the second dielectric layer 101b is greater than 0.25kλ nm, such as 0.3kλ nm; taking k=1 as an example, (second optical thickness OT2/λ) is 0.3, as shown in the first 2 as shown in Fig. In one embodiment, the first optical thickness is greater than 0.15kλ and less than 0.25kλ nm and the second optical thickness is greater than 0.25kλ and less than 0.35kλ nm. The number of dielectric layer pairs conforming to the size relationship of the above-mentioned optical thickness is more than 3 pairs continuously. In one embodiment, the sum of the first optical thickness OP1 and the second optical thickness OP2 of each dielectric layer pair of the Bragg reflection structure 101 is (0.5±0.05) kλ nm. In one embodiment, in the Bragg reflection structure 101 , the first layer is the closest to the substrate 100 and the 24th layer is the farthest from the substrate 100 . In one embodiment, the first layer is in direct contact with the substrate 100 . In another embodiment, a window layer (not shown) is selectively provided between the first layer and the substrate 100, and the window layer is transparent to the light emitted by the active structure, so as to increase the The light is extracted. The thickness of the window layer is greater than the thickness of the first dielectric layer 101a and the thickness of the second dielectric layer 101b, such as about between 300 nm and 1000 nm, and its material is different from the material of the first layer of the Bragg reflection structure 101 and different from The material of the substrate 100 .
第3圖為一光學路徑示意圖,顯示具有峰波長為λ nm之光分別經過如第一例示之布拉格反射結構之一介電層對以及一比較例之布拉格反射結構之一介電層對之光學路徑圖。具體而言,請同時參閱第1~3圖,半導體發光元件10之主動結構102c可發出具有峰波長為λ nm之光,一部份之光係朝向基板100並經過布拉格反射結構101反射而自半導體發光疊層102之表面及基板100之側面摘出。為了方便說明,第3圖僅例示布拉格反射結構101之一介電層對作為說明並以所述之比較例對照說明本實施例之功效,其中,本實施例與所述之比較例之布拉格反射結構之差異僅在於光學厚度不同,並詳述如下。如第3圖所示,於一介電層對中,所述之比較例之第一光學厚度OT1’與第二光學厚度OT2’均為0.25λ nm (以k=1為例);相對地,本實施例之第一光學厚度OT1係小於0.25λ nm(以k=1為例)且第二光學厚度OT2係大於0.25λ nm (以k=1為例) ,其中,所述之比較例之第一光學厚度OT1’與第二光學厚度OT2’的總和係等於本實施例之第一光學厚度OT1與第二光學厚度OT2的總和。主動結構102c發出之光經過所述之比較例及本實施例之介電層對所反射之光學路徑分別如路徑L1及L2所示。光進入第一介電層(OT1、OT1’)後,在第一介電層與第二介電層(OT2、OT2’)之介面發生折射並進入第二介電層;接著,在第二介電層與其下方的第一介電層(圖未示)之介面產生反射,也就是在第二介電層與其下方另一介電層對的第一介電層之介面產生反射。如第3圖所示,光路徑L2之水平位移S2大於光路徑L1之水平位移S1,顯示本揭實施例之布拉格反射結構101,相較於所述之比較例,具有較佳之光場發散效果,因此,運用本揭露之第一實施例之布拉格反射結構101可使半導體發光元件10具有較廣的發光角度。Fig. 3 is a schematic diagram of an optical path, showing that light having a peak wavelength of λ nm respectively passes through a pair of dielectric layers of the Bragg reflection structure of the first example and a pair of dielectric layers of the Bragg reflection structure of a comparative example. road map. Specifically, please refer to FIGS. 1 to 3 at the same time. The active structure 102c of the semiconductor light emitting element 10 can emit light with a peak wavelength of λ nm, and a part of the light is directed toward the substrate 100 and reflected by the Bragg reflection structure 101. The surface of the semiconductor light emitting stack 102 and the side surface of the substrate 100 are extracted. For the convenience of description, Fig. 3 only illustrates a pair of dielectric layers of the Bragg reflection structure 101 as an illustration and uses the comparative example to illustrate the effect of the present embodiment, wherein the Bragg reflection of the present embodiment and the comparative example The structure differs only in the optical thickness and is detailed below. As shown in Figure 3, in a pair of dielectric layers, the first optical thickness OT1' and the second optical thickness OT2' of the comparative example are both 0.25λ nm (taking k=1 as an example); relatively , the first optical thickness OT1 of this embodiment is less than 0.25λ nm (taking k=1 as an example) and the second optical thickness OT2 is greater than 0.25λ nm (taking k=1 as an example), wherein the comparative example The sum of the first optical thickness OT1' and the second optical thickness OT2' is equal to the sum of the first optical thickness OT1 and the second optical thickness OT2 of this embodiment. The optical paths of the light emitted by the active structure 102c and reflected by the dielectric layer pair in the comparative example and the present embodiment are shown as paths L1 and L2 respectively. After the light enters the first dielectric layer (OT1, OT1'), it is refracted at the interface between the first dielectric layer and the second dielectric layer (OT2, OT2') and enters the second dielectric layer; The interface between the dielectric layer and the underlying first dielectric layer (not shown in the figure) produces reflection, that is, the interface between the second dielectric layer and the first dielectric layer of another dielectric layer pair below produces reflection. As shown in Figure 3, the horizontal displacement S2 of the optical path L2 is greater than the horizontal displacement S1 of the optical path L1, which shows that the Bragg reflection structure 101 of the embodiment of the present disclosure has a better light field divergence effect than the comparative example mentioned above. Therefore, using the Bragg reflection structure 101 of the first embodiment of the present disclosure can make the semiconductor light emitting device 10 have a wider light emitting angle.
第4圖顯示如第一實施例所揭示之布拉格反射結構之第二例示。如第4圖所示,布拉格反射結構101係包含12對之介電層對,並依堆疊順序包含層數為第1、2、3、4…23及24層,其中,層數為第1、3、5、7…23層係為第一介電層101a,層數為第2、4、6、8…24 層係為第二介電層101b,相鄰之第一介電層101a及第二介電層101b係組成介電層對,其中,第一介電層101a之第一折射率n1大於第二介電層101b之第二折射率n2;於一介電層對中,第一介電層101a較第二介電層101b更靠近基板100。於本實施例,第一介電層101a之第一光學厚度OT1係大於0.25kλ nm,例如為0.3kλ nm;以k=1為例,(第一光學厚度OT1/λ)為0.3,如第4圖所示。於本實施例,第二介電層101b之第二光學厚度OT2係小於0.25kλ nm,例如為0.2kλ nm;以k=1為例,(第二光學厚度OT2/λ)為0.2,如第4圖所示。於一實施例,第一光學厚度大於0.25kλ且小於0.35kλ nm且第二光學厚度大於0.15kλ且小於0.25kλ nm。符合上述光學厚度之大小關係的介電層對為連續重複3對以上。於一實施例,布拉格反射結構101之每一介電層對之第一光學厚度OP1及第二光學厚度OP2之總和為(0.5±0.05) kλ nm。於一實施例,於布拉格反射結構101中,第1層係最靠近基板100且第24層係最遠離基板100。於一實施例,第1層與基板100直接接觸。Fig. 4 shows a second example of the Bragg reflection structure disclosed in the first embodiment. As shown in FIG. 4, the Bragg reflective structure 101 includes 12 pairs of dielectric layers, and includes layers 1, 2, 3, 4...23 and 24 in stacking order, wherein the number of layers is 1 , 3, 5, 7...23 layers are the first dielectric layer 101a, the number of layers is the 2nd, 4, 6, 8...24 layers are the second dielectric layer 101b, and the adjacent first dielectric layer 101a and the second dielectric layer 101b form a pair of dielectric layers, wherein the first refractive index n1 of the first dielectric layer 101a is greater than the second refractive index n2 of the second dielectric layer 101b; in a pair of dielectric layers, The first dielectric layer 101a is closer to the substrate 100 than the second dielectric layer 101b. In this embodiment, the first optical thickness OT1 of the first dielectric layer 101a is greater than 0.25kλ nm, such as 0.3kλ nm; taking k=1 as an example, (the first optical thickness OT1/λ) is 0.3, as shown in the first 4 as shown in Fig. In this embodiment, the second optical thickness OT2 of the second dielectric layer 101b is less than 0.25kλ nm, such as 0.2kλ nm; taking k=1 as an example, (second optical thickness OT2/λ) is 0.2, as shown in the first 4 as shown in Fig. In one embodiment, the first optical thickness is greater than 0.25kλ and less than 0.35kλ nm and the second optical thickness is greater than 0.15kλ and less than 0.25kλ nm. The number of dielectric layer pairs conforming to the size relationship of the above-mentioned optical thickness is more than 3 pairs continuously. In one embodiment, the sum of the first optical thickness OP1 and the second optical thickness OP2 of each dielectric layer pair of the Bragg reflection structure 101 is (0.5±0.05) kλ nm. In one embodiment, in the Bragg reflection structure 101 , the first layer is the closest to the substrate 100 and the 24th layer is the farthest from the substrate 100 . In one embodiment, the first layer is in direct contact with the substrate 100 .
第5圖為一光學路徑示意圖,顯示具有峰波長為λ nm之光分別經過如第二例示之布拉格反射結構之一介電層對以及上述之比較例之布拉格反射結構之一介電層對之光學路徑圖。具體而言,請同時參閱第1、4-5圖,半導體發光元件10之主動結構102c可發出朝向基板100之光,並經過布拉格反射結構101反射而自半導體發光疊層102之表面及基板100之側面摘出。為了方便說明,第5圖僅例示布拉格反射結構101之一介電層對作為說明並以所述之比較例對照說明本實施例之功效,其中,本實施例與所述之比較例之布拉格反射結構之差異僅在於光學厚度不同,並詳述如下。如第5圖所示,於一介電層對中,所述之比較例之第一光學厚度OT1’與第二光學厚度OT2’均為0.25λ nm (以k=1為例);相對地,本實施例之第一光學厚度OT1係大於0.25λ nm且第二光學厚度OT2係小於0.25λ nm (以k=1為例) ,其中,所述之比較例之第一光學厚度OT1’與第二光學厚度OT2’的總和係等於本實施例之第一光學厚度OT1與第二光學厚度OT2的總和。主動結構102c發出之光經過所述之比較例及本實施例之介電層對所反射之光學路徑分別如路徑L1及L3所示。光進入第一介電層(OT1、OT1’)後,在第一介電層與第二介電層(OT2、OT2’)之介面發生折射並進入第二介電層;接著,在第二介電層與其下方的第一介電層(圖未示)之介面產生反射,也就是在第二介電層與其下方另一介電層對的第一介電層之介面產生反射。如第5圖所示,路徑L3之水平位移S3小於路徑L1之水平位移S1,顯示本實施例之布拉格反射結構101,相較於所述之比較例,具有較佳之光場收斂效果,因此,運用本例示之布拉格反射結構101可使半導體發光元件10具有較集中的發光角度。Fig. 5 is a schematic diagram of an optical path, showing that light having a peak wavelength of λ nm respectively passes through a pair of dielectric layers of the Bragg reflection structure of the second example and a pair of dielectric layers of the Bragg reflection structure of the above-mentioned comparative example Optical path diagram. Specifically, please refer to Figures 1 and 4-5 at the same time. The active structure 102c of the semiconductor light emitting element 10 can emit light toward the substrate 100, and reflect it from the surface of the semiconductor light emitting stack 102 and the substrate 100 after being reflected by the Bragg reflection structure 101. Take it out from the side. For the convenience of description, Fig. 5 only illustrates a pair of dielectric layers of the Bragg reflection structure 101 as an illustration and uses the comparative example to illustrate the effect of the present embodiment, wherein the Bragg reflection of the present embodiment and the comparative example The structure differs only in the optical thickness and is detailed below. As shown in Figure 5, in a pair of dielectric layers, the first optical thickness OT1' and the second optical thickness OT2' of the comparative example are both 0.25λ nm (taking k=1 as an example); relatively , the first optical thickness OT1 of this embodiment is greater than 0.25λ nm and the second optical thickness OT2 is less than 0.25λ nm (taking k=1 as an example), wherein the first optical thickness OT1' and The sum of the second optical thickness OT2' is equal to the sum of the first optical thickness OT1 and the second optical thickness OT2 of this embodiment. The optical paths of the light emitted by the active structure 102c and reflected by the dielectric layer pair in the comparative example and the present embodiment are shown as paths L1 and L3 respectively. After the light enters the first dielectric layer (OT1, OT1'), it is refracted at the interface between the first dielectric layer and the second dielectric layer (OT2, OT2') and enters the second dielectric layer; The interface between the dielectric layer and the underlying first dielectric layer (not shown in the figure) produces reflection, that is, the interface between the second dielectric layer and the first dielectric layer of another dielectric layer pair below produces reflection. As shown in Figure 5, the horizontal displacement S3 of the path L3 is smaller than the horizontal displacement S1 of the path L1, which shows that the Bragg reflection structure 101 of this embodiment has a better light field convergence effect than the comparative example mentioned above. Therefore, Using the Bragg reflection structure 101 of this example can make the semiconductor light emitting element 10 have a more concentrated light emitting angle.
第6圖顯示符合本揭露之半導體發光元件之第二實施例。半導體發光元件20包含基板100、布拉格反射結構101、半導體發光疊層102、第一電極103、以及第二電極104。半導體發光疊層102位於基板之上表面並依序包含第一導電型半導體接觸層102a、第一導電型半導體限制層102b、主動結構102c、第二導電型半導體限制層102d、以及第二導電型半導體接觸層102e。第一導電型半導體限制層102b及第二導電型半導體限制層102d用以侷限載子(電子及電洞)於主動結構102c內以避免載子溢流出主動層103b而降低發光效率,第一導電型半導體限制層102b及第二導電型半導體限制層102d各具有一能隙大於主動結構102c之能隙。布拉格反射結構101位於第二導電型半導體接觸層102e上,其中,布拉格反射結構101包含一開口以露出部份之第二導電型半導體接觸層102e。第一導電型半導體接觸層102a具有一摻雜濃度大於第一導電型半導體限制層102b之摻雜濃度,並且第一電極103位於第一導電型半導體接觸層102a之上並與第一導電型半導體接觸層102a形成良好的電性接觸,例如歐姆接觸。第二導電型半導體接觸層102e具有一摻雜濃度大於第二導電型半導體限制層102d之摻雜濃度,並且第二電極104位於第二導電型半導體接觸層102e之上並透過所述之開口與第二導電型半導體接觸層102e形成良好的電性接觸,例如歐姆接觸。主動結構102c例如包含多重量子井(Multiple Quantum Wells; MQW)結構,並於驅動時發出具有一峰波長為λ nm之可見光或不可見光。第一導電型例如為n型且第二導電型例如為p型。FIG. 6 shows a second embodiment of a semiconductor light emitting device according to the present disclosure. The semiconductor light emitting device 20 includes a substrate 100 , a Bragg reflective structure 101 , a semiconductor light emitting stack 102 , a first electrode 103 , and a second electrode 104 . The semiconductor light emitting stack 102 is located on the upper surface of the substrate and sequentially includes a first conductivity type semiconductor contact layer 102a, a first conductivity type semiconductor confinement layer 102b, an active structure 102c, a second conductivity type semiconductor confinement layer 102d, and a second conductivity type semiconductor confinement layer 102d, and a second conductivity type semiconductor confinement layer 102b The semiconductor contact layer 102e. The first conductivity type semiconductor confinement layer 102b and the second conductivity type semiconductor confinement layer 102d are used to confine carriers (electrons and holes) in the active structure 102c to prevent carriers from overflowing the active layer 103b and reduce luminous efficiency. The semiconductor confinement layer 102b of the first conductivity type and the semiconductor confinement layer 102d of the second conductivity type each have an energy gap larger than that of the active structure 102c. The Bragg reflective structure 101 is located on the second conductive type semiconductor contact layer 102e, wherein the Bragg reflective structure 101 includes an opening to expose part of the second conductive type semiconductor contact layer 102e. The first conductivity type semiconductor contact layer 102a has a doping concentration higher than that of the first conductivity type semiconductor confinement layer 102b, and the first electrode 103 is located on the first conductivity type semiconductor contact layer 102a and connected to the first conductivity type semiconductor contact layer 102a. The contact layer 102a forms a good electrical contact, such as an ohmic contact. The second conductivity type semiconductor contact layer 102e has a doping concentration greater than that of the second conductivity type semiconductor confinement layer 102d, and the second electrode 104 is located on the second conductivity type semiconductor contact layer 102e and passes through the opening and The second conductivity type semiconductor contact layer 102e forms a good electrical contact, such as an ohmic contact. The active structure 102c includes, for example, a multiple quantum well (Multiple Quantum Wells; MQW) structure, and emits visible light or invisible light with a peak wavelength of λ nm when driven. The first conductivity type is, for example, n-type and the second conductivity type is, for example, p-type.
於另一實施例中,布拉格反射結構101除了覆蓋第二導電型半導體接觸層102e,更覆蓋半導體發光疊層102的表面、第一導電型半導體接觸層102a的表面、第一電極103以及第二電極104的部分表面。布拉格反射結構101包含一開口露出部份之第一電極103另一部分表面,以及另一開口露出第二電極104另一部分表面。半導體發光元件20更包含第一、第二電極墊(圖未示),分別透過所述之兩個開口與第一電極103和第二電極104形成電性接觸。第一電極墊及第二電極墊的面積分別大於第一電極103及第二電極104。第一、第二電極墊包含金屬材料例如Sn、Au等金屬元素或其合金所構成的單一層或多層堆疊結構例如Sn/Au、Sn/AuSn、SnAg/AuSn、SnAg/Sn/AuSn等,以用於在封裝製程時與載板形成電連接。In another embodiment, in addition to covering the second conductivity type semiconductor contact layer 102e, the Bragg reflection structure 101 also covers the surface of the semiconductor light emitting stack 102, the surface of the first conductivity type semiconductor contact layer 102a, the first electrode 103 and the second part of the surface of the electrode 104. The Bragg reflection structure 101 includes an opening exposing part of the other part of the surface of the first electrode 103 , and another opening exposing the other part of the surface of the second electrode 104 . The semiconductor light-emitting device 20 further includes first and second electrode pads (not shown in the figure), respectively forming electrical contact with the first electrode 103 and the second electrode 104 through the two openings. Areas of the first electrode pad and the second electrode pad are larger than the first electrode 103 and the second electrode 104 respectively. The first and second electrode pads include metal materials such as Sn, Au and other metal elements or a single-layer or multi-layer stack structure such as Sn/Au, Sn/AuSn, SnAg/AuSn, SnAg/Sn/AuSn, etc., to It is used to form an electrical connection with the carrier board during the packaging process.
布拉格反射結構101包含複數介電層對,其中,每一介電層對分別包含第一介電層101a及第二介電層101b,第一介電層101a具有第一幾何厚度(geometrical thickness) GT1、第一光學厚度(optical thickness) OT1、及第一折射率n1,第二介電層101b具有第二幾何厚度 GT2、第二光學厚度OT2及第二折射率n2,第一光學厚度OT1及第二光學厚度OT2其中之一小於0.25kλ nm且第一光學厚度及第二光學厚度之另一個大於0.25kλ nm,k為正奇數,例如1、3、5或7。於本實施例中,第一折射率n1大於第二折射率n2,例如,第一折射率n1大於等於1.7且小於等於3之間,第二折射率n2大於等於1.2且小於1.7;第一介電層101a例如包含氧化鈦(TiO
x)、氧化鈮(NbO
x)或氧化鉭(TaO
x)等,第二介電層101b例如包含氧化矽(SiO
x) 、氧化鋁(AlO
x)或氟化鎂(MgF
x)等。於另一實施例中,第一折射率n1小於第二折射率n2,例如第一折射率n1大於或等於1.2且小於1.7,第二折射率n2大於或等於1.7且小於或等於3;第一介電層101a例如包含氧化矽(SiO
x)、氧化鋁(AlO
x)或氟化鎂(MgF
x)等,第二介電層101b例如包含氧化鈦(TiO
x)、氧化鈮(NbO
x)或氧化鉭(TaO
x)等。於各實施例中,符合該實施例光學厚度之大小關係的介電層對為連續重複3對以上,例如4~20對。本實施例之半導體發光疊層102位於布拉格反射結構101及基板100之間,因此,主動結構102c發出之光線被布拉格反射結構101反射回半導體發光疊層102,並穿透基板100而自半導體發光疊層102之側面、基板100之下表面100u、及基板100之側面摘出。布拉格反射結構101對主動結構102c所發出之光具有70%之反射率。
The Bragg reflection structure 101 includes a plurality of dielectric layer pairs, wherein each pair of dielectric layers includes a first dielectric layer 101a and a second dielectric layer 101b, and the first dielectric layer 101a has a first geometrical thickness. GT1, a first optical thickness (optical thickness) OT1, and a first refractive index n1, the second dielectric layer 101b has a second geometric thickness GT2, a second optical thickness OT2, and a second refractive index n2, the first optical thickness OT1 and One of the second optical thickness OT2 is less than 0.25kλ nm and the other of the first optical thickness and the second optical thickness is greater than 0.25kλ nm, k is a positive odd number, such as 1, 3, 5 or 7. In this embodiment, the first refractive index n1 is greater than the second refractive index n2, for example, the first refractive index n1 is greater than or equal to 1.7 and less than or equal to 3, and the second refractive index n2 is greater than or equal to 1.2 and less than 1.7; The electrical layer 101a includes, for example, titanium oxide (TiO x ), niobium oxide (NbO x ) or tantalum oxide (TaO x ), etc., and the second dielectric layer 101b includes, for example, silicon oxide (SiO x ), aluminum oxide (AlO x ) or fluorine Magnesium oxide (MgF x ) and the like. In another embodiment, the first refractive index n1 is smaller than the second refractive index n2, for example, the first refractive index n1 is greater than or equal to 1.2 and less than 1.7, and the second refractive index n2 is greater than or equal to 1.7 and less than or equal to 3; the first The dielectric layer 101a includes, for example, silicon oxide (SiO x ), aluminum oxide (AlO x ) or magnesium fluoride (MgF x ), etc., and the second dielectric layer 101b includes, for example, titanium oxide (TiO x ), niobium oxide (NbO x ) Or tantalum oxide (TaO x ), etc. In each embodiment, the number of dielectric layer pairs conforming to the size relationship of the optical thickness of the embodiment is more than 3 pairs, for example, 4-20 pairs. The semiconductor light emitting stack 102 of this embodiment is located between the Bragg reflective structure 101 and the substrate 100, therefore, the light emitted by the active structure 102c is reflected by the Bragg reflective structure 101 back to the semiconductor light emitting stack 102, and penetrates the substrate 100 to emit light from the semiconductor The side surfaces of the stack 102, the lower surface 100u of the substrate 100, and the side surfaces of the substrate 100 are extracted. The Bragg reflection structure 101 has a reflectivity of 70% for the light emitted by the active structure 102c.
於一實施例中,半導體發光元件20可選擇性地包含一底層(圖未示)介於布拉格反射結構101與半導體發光疊層102之間。也就是說,先於半導體發光疊層102上形成所述之底層,接著再形成布拉格反射結構101於所述之底層上。所述之底層包含介電材料,其厚度大於第一介電層101a及第二介電層101b的厚度。所述之底層可提供保護半導體發光元件20或保護半導體發光疊層102的功能,例如阻擋外界水氣進入半導體發光元件20。In one embodiment, the semiconductor light emitting device 20 may optionally include a bottom layer (not shown) between the Bragg reflective structure 101 and the semiconductor light emitting stack 102 . That is to say, the bottom layer is formed on the semiconductor light emitting stack 102 first, and then the Bragg reflection structure 101 is formed on the bottom layer. The bottom layer includes a dielectric material whose thickness is greater than that of the first dielectric layer 101a and the second dielectric layer 101b. The bottom layer can provide the function of protecting the semiconductor light emitting device 20 or the semiconductor light emitting stack 102 , such as preventing outside moisture from entering the semiconductor light emitting device 20 .
於另一實施例中,半導體發光元件20可選擇性地包含一上層(圖未示)使得布拉格反射結構101介於所述之上層及半導體發光疊層102之間。也就是說,先於半導體發光疊層102上形成布拉格反射結構101,接著再形成所述之上層。所述之上層包含介電材料,其厚度大於第一介電層101a及第二介電層101b的厚度。所述之上層可增加整體布拉格反射結構101的強度,例如當布拉格反射結構101受到外力時,所述之上層避免布拉格反射結構101因外力而破裂損傷。In another embodiment, the semiconductor light emitting device 20 may optionally include an upper layer (not shown in the figure) so that the Bragg reflection structure 101 is interposed between the upper layer and the semiconductor light emitting stack 102 . That is to say, the Bragg reflective structure 101 is formed on the semiconductor light emitting stack 102 first, and then the upper layer is formed. The upper layer includes a dielectric material with a thickness greater than that of the first dielectric layer 101a and the second dielectric layer 101b. The upper layer can increase the strength of the Bragg reflective structure 101 as a whole, for example, when the Bragg reflective structure 101 is subjected to an external force, the upper layer can prevent the Bragg reflective structure 101 from breaking due to external force.
於另一實施例中,於形成布拉格反射結構101之前,可藉由原子層沉積法(Atomic Layer Deposition)直接於第二導電型半導體接觸層102e之表面上形成一緻密層(圖未示)以保護半導體發光疊層102。緻密層的材料包含氧化矽、氧化鋁、氧化鉿、氧化鉭、氧化鋯、氧化釔、氧化鑭、氧化鉭、氮化矽、氮化鋁或氮氧化矽。於本實施例中,緻密層與半導體疊層12相接之介面包含金屬元素及氧,其中金屬元素包含鋁、鉿、鉭、鋯、釔、鑭或鉭。緻密層包含一厚度介於50 Å~2000 Å之間,較佳介於100 Å~1500 Å之間。於一實施例中,緻密層可共形覆蓋形成於半導體發光疊層102上,藉由其膜質特性可提供半導體發光疊層102一較佳的保護作用,例如避免水氣進入半導體發光疊層102,且可提高布拉格反射結構101與半導體發光疊層102之間的附著力。In another embodiment, before forming the Bragg reflection structure 101, a dense layer (not shown) may be directly formed on the surface of the second conductivity type semiconductor contact layer 102e by atomic layer deposition (Atomic Layer Deposition) to Protect the semiconductor light emitting stack 102 . The material of the dense layer includes silicon oxide, aluminum oxide, hafnium oxide, tantalum oxide, zirconium oxide, yttrium oxide, lanthanum oxide, tantalum oxide, silicon nitride, aluminum nitride or silicon oxynitride. In this embodiment, the interface between the dense layer and the semiconductor stack 12 contains metal elements and oxygen, wherein the metal elements include aluminum, hafnium, tantalum, zirconium, yttrium, lanthanum or tantalum. The dense layer includes a thickness between 50 Å~2000 Å, preferably between 100 Å~1500 Å. In one embodiment, the dense layer can be conformally covered and formed on the semiconductor light emitting stack 102, and its film quality can provide a better protection for the semiconductor light emitting stack 102, such as preventing moisture from entering the semiconductor light emitting stack 102. , and can improve the adhesion between the Bragg reflection structure 101 and the semiconductor light emitting stack 102 .
於一實施例中,半導體發光元件20包含布拉格反射結構101,其中第一介電層101a之折射率大於第二介電層101b之折射率n2,第一介電層101a之第一光學厚度OT1係小於0.25kλ nm,第二介電層101b之第二光學厚度OT2係大於0.25kλ nm。如同第一實施例的半導體發光元件10,可使半導體發光元件20具有較廣的發光角度。於另一實施例中,半導體發光元件20包含布拉格反射結構101,其中第一介電層101a之折射率大於第二介電層101b之折射率n2,第一介電層101a之第一光學厚度OT1係大於0.25kλ nm,第二介電層101b之第二光學厚度OT2係小於0.25kλ nm。如同第一實施例的半導體發光元件10,可使半導體發光元件20具有較集中的發光角度。In one embodiment, the semiconductor light emitting element 20 includes a Bragg reflection structure 101, wherein the refractive index of the first dielectric layer 101a is greater than the refractive index n2 of the second dielectric layer 101b, and the first optical thickness OT1 of the first dielectric layer 101a is less than 0.25kλ nm, and the second optical thickness OT2 of the second dielectric layer 101b is greater than 0.25kλ nm. Like the semiconductor light emitting element 10 of the first embodiment, the semiconductor light emitting element 20 can have a wider light emitting angle. In another embodiment, the semiconductor light emitting element 20 includes a Bragg reflection structure 101, wherein the refractive index of the first dielectric layer 101a is greater than the refractive index n2 of the second dielectric layer 101b, and the first optical thickness of the first dielectric layer 101a OT1 is greater than 0.25kλ nm, and the second optical thickness OT2 of the second dielectric layer 101b is less than 0.25kλ nm. Like the semiconductor light emitting element 10 of the first embodiment, the semiconductor light emitting element 20 can have a relatively concentrated light emitting angle.
第7圖顯示符合本揭露之半導體發光元件之第三實施例。半導體發光元件30與半導體發光元件20相似,其布拉格反射結構101與半導體發光元件20的布拉格反射結構101相同,差異在於半導體發光元件30不包含基板100。本實施例之主動結構102c發出之光線被布拉格反射結構101反射回半導體發光疊層102,而自半導體發光疊層102之側面以及半導體發光疊層102之上表面102u摘出。FIG. 7 shows a third embodiment of a semiconductor light emitting device according to the present disclosure. The semiconductor light emitting element 30 is similar to the semiconductor light emitting element 20 , and its Bragg reflection structure 101 is the same as the Bragg reflection structure 101 of the semiconductor light emitting element 20 , the difference is that the semiconductor light emitting element 30 does not include the substrate 100 . The light emitted by the active structure 102c of this embodiment is reflected back to the semiconductor light emitting stack 102 by the Bragg reflection structure 101, and extracted from the side surface of the semiconductor light emitting stack 102 and the upper surface 102u of the semiconductor light emitting stack 102.
於一實施例中,半導體發光元件30包含布拉格反射結構101,其中第一介電層101a之折射率大於第二介電層101b之折射率n2,第一介電層101a之第一光學厚度OT1係小於0.25kλ nm,第二介電層101b之第二光學厚度OT2係大於0.25kλ nm。如同第一實施例的半導體發光元件10,可使半導體發光元件30具有較廣的發光角度。於另一實施例中,半導體發光元件30包含布拉格反射結構101,其中第一介電層101a之折射率大於第二介電層101b之折射率n2,第一介電層101a之第一光學厚度OT1係大於0.25kλ nm,第二介電層101b之第二光學厚度OT2係小於0.25kλ nm。如同第一實施例的半導體發光元件10,可使半導體發光元件30具有較集中的發光角度。In one embodiment, the semiconductor light emitting element 30 includes a Bragg reflection structure 101, wherein the refractive index of the first dielectric layer 101a is greater than the refractive index n2 of the second dielectric layer 101b, and the first optical thickness OT1 of the first dielectric layer 101a is less than 0.25kλ nm, and the second optical thickness OT2 of the second dielectric layer 101b is greater than 0.25kλ nm. Like the semiconductor light emitting element 10 of the first embodiment, the semiconductor light emitting element 30 can have a wider light emitting angle. In another embodiment, the semiconductor light emitting element 30 includes a Bragg reflective structure 101, wherein the refractive index of the first dielectric layer 101a is greater than the refractive index n2 of the second dielectric layer 101b, and the first optical thickness of the first dielectric layer 101a OT1 is greater than 0.25kλ nm, and the second optical thickness OT2 of the second dielectric layer 101b is less than 0.25kλ nm. Like the semiconductor light emitting element 10 of the first embodiment, the semiconductor light emitting element 30 can have a more concentrated light emitting angle.
於上述各實施例中,布拉格反射結構101更可包含複數組介電層對(圖未示),具體而言,布拉格反射結構101除了包含由第一介電層101a與第二介電層101b所組成之介電層對之外,更包含由第三介電層與第四介電層所組成之其他介電層對,其中,所述之第三介電層與第一介電層101a具有不同的光學厚度,及/或所述之第四介電層與第二介電層101b具有不同光學厚度。於一實施例中,所述之第三介電層與第一介電層101a包含不同材料,及/或所述之第四介電層與第二介電層101b包含不同材料。於另一實施例中,所述之第三介電層與第一介電層具有不同幾何厚度,及/或所述之第四介電層與第二介電層101b具有不同幾何厚度。所述之第三介電層具有第三幾何厚度GT3、第三光學厚度OT3及第三折射率n3,所述之第四介電層具有第四幾何厚度GT4、第四光學厚度OT4及第四折射率n4。第三光學厚度OT3及第四光學厚度OT4其中之一小於0.25kλ nm且第三光學厚度OT3及第四光學厚度OT4之另一個大於0.25kλ nm,k為正奇數。In the above-mentioned embodiments, the Bragg reflection structure 101 may further include multiple sets of dielectric layer pairs (not shown in the figure). Specifically, the Bragg reflection structure 101 includes the first dielectric layer 101a and the second dielectric layer 101b In addition to the formed dielectric layer pair, it further includes other dielectric layer pairs composed of the third dielectric layer and the fourth dielectric layer, wherein the third dielectric layer and the first dielectric layer 101a have different optical thicknesses, and/or the fourth dielectric layer and the second dielectric layer 101b have different optical thicknesses. In one embodiment, the third dielectric layer and the first dielectric layer 101a comprise different materials, and/or the fourth dielectric layer and the second dielectric layer 101b comprise different materials. In another embodiment, the third dielectric layer and the first dielectric layer have different geometric thicknesses, and/or the fourth dielectric layer and the second dielectric layer 101b have different geometric thicknesses. The third dielectric layer has a third geometric thickness GT3, a third optical thickness OT3 and a third refractive index n3, and the fourth dielectric layer has a fourth geometric thickness GT4, a fourth optical thickness OT4 and a fourth Refractive index n4. One of the third optical thickness OT3 and the fourth optical thickness OT4 is less than 0.25kλ nm and the other of the third optical thickness OT3 and the fourth optical thickness OT4 is greater than 0.25kλ nm, k is a positive odd number.
於一實施例中,第一介電層101a之第一折射率n1大於第二介電層101b之第二折射率n2,所述之第三介電層之第三折射率n3大於所述之第四介電層之第四折射率n4。於一介電層對中,第一介電層101a較第二介電層101b更靠近基板100。於一介電層對中,所述之第三介電層較所述之第四介電層更靠近基板100。其中,第一介電層101a之第一光學厚度OT1與所述之第三介電層之第三光學厚度OT3皆小於0.25kλ nm,第二介電層101b之第二光學厚度OT2與所述之第四介電層之第四光學厚度OT4皆大於0.25kλ nm。符合上述光學厚度之大小關係的介電層對為連續堆疊3對以上。In one embodiment, the first refractive index n1 of the first dielectric layer 101a is greater than the second refractive index n2 of the second dielectric layer 101b, and the third refractive index n3 of the third dielectric layer is greater than the aforementioned The fourth refractive index n4 of the fourth dielectric layer. In a pair of dielectric layers, the first dielectric layer 101a is closer to the substrate 100 than the second dielectric layer 101b. In a pair of dielectric layers, the third dielectric layer is closer to the substrate 100 than the fourth dielectric layer. Wherein, the first optical thickness OT1 of the first dielectric layer 101a and the third optical thickness OT3 of the third dielectric layer are both less than 0.25kλ nm, and the second optical thickness OT2 of the second dielectric layer 101b is the same as the third optical thickness OT3 of the third dielectric layer. The fourth optical thickness OT4 of the fourth dielectric layer is greater than 0.25kλ nm. Dielectric layer pairs conforming to the size relationship of the above-mentioned optical thickness are more than 3 pairs that are stacked continuously.
於另一實施例中,第一介電層101a之第一折射率n1大於第二介電層101b之第二折射率n2,所述之第三介電層之第三折射率n3大於所述之第四介電層之第四折射率n4。於一介電層對中,第一介電層101a較第二介電層101b更靠近基板100。於一介電層對中,所述之第三介電層較所述之第四介電層更靠近基板100。其中,第一介電層101a之第一光學厚度OT1與所述之第三介電層之第三光學厚度OT3皆大於0.25kλ nm,第二介電層101b之第二光學厚度OT2與所述之第四介電層之第四光學厚度OT4皆小於0.25kλ nm。符合上述光學厚度之大小關係的介電層對為連續堆疊3對以上。In another embodiment, the first refractive index n1 of the first dielectric layer 101a is greater than the second refractive index n2 of the second dielectric layer 101b, and the third refractive index n3 of the third dielectric layer is greater than the The fourth refractive index n4 of the fourth dielectric layer. In a pair of dielectric layers, the first dielectric layer 101a is closer to the substrate 100 than the second dielectric layer 101b. In a pair of dielectric layers, the third dielectric layer is closer to the substrate 100 than the fourth dielectric layer. Wherein, the first optical thickness OT1 of the first dielectric layer 101a and the third optical thickness OT3 of the third dielectric layer are both larger than 0.25kλ nm, and the second optical thickness OT2 of the second dielectric layer 101b is the same as the third optical thickness OT3 of the third dielectric layer The fourth optical thickness OT4 of the fourth dielectric layer is less than 0.25kλ nm. Dielectric layer pairs conforming to the size relationship of the above-mentioned optical thickness are more than 3 pairs that are stacked continuously.
於上述之各實施例中,基板100可為一磊晶基板用以透過例如有機金屬化學氣相沉積法(MOCVD)磊晶成長半導體發光疊層102。於一實施例,半導體發光疊層102與基板100之間具有複數個彼此分開之凸起,用以改變光的行進路徑以增加光摘出效率。於一實施例中,所述之凸起係直接圖案化基板100之表面至一深度所形成,因此具有與基板100相同之組成材料。於另一實施例中,先於基板100的上表面形成一透光材料層後,再將透光材料層圖案化以形成所述之凸起,其中,所述之凸起與基板100具有不同之組成材料。或者,基板100可為一接合承載基板,基板100與半導體發光疊層102之間更包含一接合層 (bonding layer) (圖未示),原磊晶成長在磊晶基板上的半導體發光疊層102,可利用晶圓接合(wafer bonding)技術將半導體發光疊層102透過接合層接合至基板100。其中接合層相對於半導體發光疊層102所發之光為透明,其材料可為絕緣材料,例如聚亞醯胺(PI)、苯并環丁烯(BCB)、過氟環丁烷(PFCB)、氧化鎂(MgO)、Su8、環氧樹脂(Epoxy)、丙烯酸樹脂(Acrylic Resin)、環烯烴聚合物(COC)、聚甲基丙烯酸甲酯(PMMA)、聚對苯二甲酸乙二酯(PET)、聚碳酸酯(PC)、聚醚醯亞胺(Polyetherimide)、氟碳聚合物(Fluorocarbon Polymer)、玻璃(Glass)、氧化鋁(AlOx)、氧化矽(SiOx)、氧化鈦(TiOx)、氮化矽(SiNx)或旋塗玻璃(SOG)。In the above-mentioned embodiments, the substrate 100 can be an epitaxial substrate for epitaxially growing the semiconductor light emitting stack 102 by, for example, metal organic chemical vapor deposition (MOCVD). In one embodiment, there are a plurality of protrusions separated from each other between the semiconductor light emitting stack 102 and the substrate 100 to change the path of light to increase light extraction efficiency. In one embodiment, the protrusions are formed by directly patterning the surface of the substrate 100 to a depth, and thus have the same composition material as the substrate 100 . In another embodiment, after forming a light-transmitting material layer on the upper surface of the substrate 100, the light-transmitting material layer is patterned to form the protrusions, wherein the protrusions and the substrate 100 have different The constituent materials. Alternatively, the substrate 100 can be a bonding carrier substrate, and a bonding layer (bonding layer) (not shown) is further included between the substrate 100 and the semiconductor light emitting stack 102. The semiconductor light emitting stack grown on the epitaxial substrate 102 , the semiconductor light emitting stack 102 can be bonded to the substrate 100 through the bonding layer by using a wafer bonding technology. Wherein the bonding layer is transparent to the light emitted by the semiconductor light-emitting stack 102, and its material can be an insulating material, such as polyimide (PI), benzocyclobutene (BCB), perfluorocyclobutane (PFCB) , magnesium oxide (MgO), Su8, epoxy resin (Epoxy), acrylic resin (Acrylic Resin), cycloolefin polymer (COC), polymethyl methacrylate (PMMA), polyethylene terephthalate ( PET), polycarbonate (PC), polyetherimide (Polyetherimide), fluorocarbon polymer (Fluorocarbon Polymer), glass (Glass), aluminum oxide (AlOx), silicon oxide (SiOx), titanium oxide (TiOx) , silicon nitride (SiNx) or spin-on-glass (SOG).
第一導電型半導體接觸層102a、第一導電型半導體侷限層102b、主動結構102c、第二導電型半導體限制層102d、以及第二導電型半導體接觸層102e均包含相同系列之III-V族化合物半導體材料,例如AlInGaAs系列、AlGaInP系列或AlInGaN系列。其中,AlInGaAs系列可表示為(Al
x1In
(1-x1))
1-x2Ga
x2As,AlInGaP系列可表示為(Al
y1In
(1-y1))
1-y2Ga
y2P,AlInGaN 系列可表示為(Al
z1In
(1-z1))
1-z2Ga
z2N,其中,0≦x1、y1、z1、 x2、y2、z2≦1,其餘未列之系列材料,可依此類推。半導體發光元件發出之光線決定於主動結構102c之材料組成,例如主動結構102c之材料包含AlGaInP系列時,可發出峰波長λ為700至1700 nm 的紅外光、610 nm至700 nm的紅光、或是峰波長λ為530 nm至570 nm的黃光。當主動結構102c之材料包含InGaN系列時,可發出峰波長λ為400 nm至490 nm的藍光、深藍光,或是峰波長λ為490 nm至550 nm的綠光。當主動結構102c材料包含AlGaN系列時,可發出峰波長λ為250 nm至400 nm的紫外光。
The first conductivity type semiconductor contact layer 102a, the first conductivity type semiconductor confinement layer 102b, the active structure 102c, the second conductivity type semiconductor confinement layer 102d, and the second conductivity type semiconductor confinement layer 102e all comprise the same series of III-V compounds Semiconductor materials, such as AlInGaAs series, AlGaInP series or AlInGaN series. Among them, the AlInGaAs series can be expressed as (Al x1 In (1-x1) ) 1-x2 Ga x2 As, the AlInGaP series can be expressed as (Al y1 In (1-y1) ) 1-y2 Ga y2 P, and the AlInGaN series can be expressed as It is (Al z1 In (1-z1) ) 1-z2 Ga z2 N, where 0≦x1, y1, z1, x2, y2, z2≦1, other series materials not listed, can be deduced in the same way. The light emitted by the semiconductor light-emitting element depends on the material composition of the active structure 102c. For example, when the material of the active structure 102c includes AlGaInP series, it can emit infrared light with a peak wavelength λ of 700 to 1700 nm, red light from 610 nm to 700 nm, or It is yellow light with a peak wavelength λ of 530 nm to 570 nm. When the material of the active structure 102c includes InGaN series, it can emit blue light, dark blue light with a peak wavelength λ of 400 nm to 490 nm, or green light with a peak wavelength λ of 490 nm to 550 nm. When the material of the active structure 102c includes AlGaN series, it can emit ultraviolet light with a peak wavelength λ of 250 nm to 400 nm.
第一電極103及第二電極104係用以電性連接至外部電源或外部元件,可包含透明導電材料及/或金屬材料。透明導電材料包含金屬氧化物、類鑽碳薄膜(DLC)、石墨烯或上述材料之組合。金屬材料包含但不限於銅(Cu)、鋁(Al)、銦(In)、錫(Sn)、金(Au)、鉑(Pt)、鋅(Zn)、銀(Ag)、鈦(Ti)、鎳(Ni)、鉛(Pb)、鈀(Pd)、鍺(Ge)、鉻(Cr)、鈷(Co)、鎘(Cd)、錳(Mn)、銻(Sb) 、鉍(Bi)、鎵(Ga)、鎢(W)、鈹(Be)或上述材料之合金等。The first electrode 103 and the second electrode 104 are used to electrically connect to an external power source or external components, and may include transparent conductive materials and/or metal materials. The transparent conductive material includes metal oxide, diamond-like carbon (DLC), graphene or a combination of the above materials. Metal materials include but not limited to copper (Cu), aluminum (Al), indium (In), tin (Sn), gold (Au), platinum (Pt), zinc (Zn), silver (Ag), titanium (Ti) , nickel (Ni), lead (Pb), palladium (Pd), germanium (Ge), chromium (Cr), cobalt (Co), cadmium (Cd), manganese (Mn), antimony (Sb), bismuth (Bi) , gallium (Ga), tungsten (W), beryllium (Be) or alloys of the above materials, etc.
第8A圖為一側視圖,顯示符合本揭露之發光元件封裝結構7之一實施例。第8B圖為第8A圖中沿A-A’線段之截面圖。FIG. 8A is a side view showing an embodiment of a light emitting device packaging structure 7 according to the present disclosure. Figure 8B is a cross-sectional view along line A-A' among Figure 8A.
發光元件封裝結構7包括半導體發光元件10、封裝體16、開口160、第一導線端子50a及一第二導線端子50b、金屬連接線14、以及透光樹脂23。第一導線端子50a及第二導線端子50b分開地被封裝體16封裝於其中,開口160露出第一導線端子50a之一端及第二導線端子50b之一端,半導體發光元件10位於開口160內以及第二導線端子50b上,利用金屬連接線14(bonding wire)分別和第一導線端子50a及第二導線端子50b電性連接。透光樹脂23填充於開口160,透光樹脂23可包含有波長轉換材料(圖未示),例如螢光粉及/或散射材料(圖未示)等。此外,第一導線端子50a之另一端和第二導線端子50b之另一端自封裝體16之外側突出,以與外部電源或外部電子元件進行電性連接。如第8A圖所示,第一導線端子50a和第二導線端子50b從封裝體16的一側表面彎折延伸至其相鄰之另一側表面。The light-emitting device packaging structure 7 includes a semiconductor light-emitting device 10 , a package body 16 , an opening 160 , a first wire terminal 50 a and a second wire terminal 50 b , metal connecting wires 14 , and a light-transmitting resin 23 . The first wire terminal 50a and the second wire terminal 50b are separately packaged in the package body 16, the opening 160 exposes one end of the first wire terminal 50a and one end of the second wire terminal 50b, and the semiconductor light emitting element 10 is located in the opening 160 and the second wire terminal 50b. The two wire terminals 50b are electrically connected to the first wire terminal 50a and the second wire terminal 50b respectively by metal connecting wires 14 (bonding wire). The light-transmitting resin 23 is filled in the opening 160 , and the light-transmitting resin 23 may include wavelength conversion materials (not shown), such as phosphor powder and/or scattering materials (not shown). In addition, the other end of the first wire terminal 50a and the other end of the second wire terminal 50b protrude from the package body 16 for electrical connection with an external power source or external electronic components. As shown in FIG. 8A, the first wire terminal 50a and the second wire terminal 50b are bent and extended from one side surface of the package body 16 to the other adjacent side surface thereof.
發光元件封裝結構7的開口160具有縱長形狀,其內安裝有半導體發光元件10。於一實施例中,半導體發光元件10由上視觀之為一縱長型。開口160的長邊方向(X軸方向)與半導體發光元件10的長邊方向一致,開口160的側壁160a可為一傾斜面,以反射及導引半導體發光元件10所發出的光R朝向開口處的出光方向摘出,增加整體發光元件封裝結構7的發光效率。縱長形狀的半導體發光元件10搭配縱長形狀的封裝結構7,適用於側投式背光顯示器的背光模組。於一實施例中,半導體發光元件10在Y軸方向上與側壁160a之最頂端的間距D2小於半導體發光元件10在X軸方向上與側壁160a之最頂端的間距D1。隨著側投式背光顯示器的輕薄化,發光元件封裝結構7在Y軸方向上的寬度越來越小,同樣地,半導體發光元件10在Y軸方向上與側壁160a之最頂端的距離D2也越來越小。當半導體發光元件10在Y軸方向上與側壁160a之最頂端的距離D2越小時,側壁160a之傾斜角度越接近垂直而使得半導體發光元件10所發出的側向光在側壁160a來回反射次數增加而提高被側壁160a吸收的比例,使得發光元件封裝結構7之亮度下降。依據本揭露一實施例之半導體發光元件10,其包含前述第二例示布拉格反射結構101,具有較集中的發光角度,亦即從半導體發光元件10正面出光比例較高,側面出光比例較少。因此,將半導體發光元件10設置於發光元件封裝結構7中,由於從半導體發光元件10側面出光比例較少,可進一步減少半導體發光元件10的側向光被側壁160a所吸收的可能性,進而提升發光元件封裝結構7的亮度。本揭露所述之半導體發光元件10的長寬比可隨發光元件封裝結構的設計改變而有所調整,本揭露所述之發光元件皆適用於在Y軸方向上的寬度較X軸方向上的小的長方形封裝結構。於一實施例中,例如半導體發光元件長寬比可為2比1或以上,皆適用於發光元件封裝結構7。The opening 160 of the light emitting element packaging structure 7 has a vertically long shape, and the semiconductor light emitting element 10 is mounted therein. In one embodiment, the semiconductor light emitting device 10 is vertically long when viewed from above. The long side direction (X-axis direction) of the opening 160 is consistent with the long side direction of the semiconductor light emitting element 10, and the side wall 160a of the opening 160 can be an inclined surface to reflect and guide the light R emitted by the semiconductor light emitting element 10 toward the opening. The light-emitting direction is extracted to increase the luminous efficiency of the overall light-emitting element packaging structure 7 . The elongated semiconductor light-emitting element 10 is matched with the elongated packaging structure 7, and is suitable for a backlight module of a side-projection backlight display. In one embodiment, the distance D2 between the semiconductor light-emitting device 10 and the topmost sidewall 160a in the Y-axis direction is smaller than the distance D1 between the semiconductor light-emitting device 10 and the topmost sidewall 160a in the X-axis direction. With the thinning of side-projection backlight displays, the width of the light-emitting element packaging structure 7 in the Y-axis direction is getting smaller and smaller. Similarly, the distance D2 between the semiconductor light-emitting element 10 and the topmost side wall 160a in the Y-axis direction is also Getting smaller and smaller. When the distance D2 between the semiconductor light-emitting element 10 and the top of the sidewall 160a in the Y-axis direction is smaller, the inclination angle of the sidewall 160a is closer to vertical, so that the number of times of back-and-forth reflection of the lateral light emitted by the semiconductor light-emitting element 10 on the sidewall 160a increases. Increasing the ratio of absorption by the sidewall 160 a reduces the brightness of the light emitting element packaging structure 7 . The semiconductor light emitting device 10 according to an embodiment of the present disclosure includes the aforementioned second exemplary Bragg reflection structure 101 , which has a relatively concentrated light emitting angle, that is, a higher ratio of light emitted from the front side of the semiconductor light emitting device 10 , and a smaller ratio of emitted light from the side. Therefore, when the semiconductor light emitting element 10 is arranged in the light emitting element packaging structure 7, since the proportion of light emitted from the side of the semiconductor light emitting element 10 is small, the possibility of the side light of the semiconductor light emitting element 10 being absorbed by the side wall 160a can be further reduced, thereby improving Brightness of the light emitting element packaging structure 7 . The aspect ratio of the semiconductor light-emitting element 10 described in this disclosure can be adjusted according to the design of the packaging structure of the light-emitting element. Small rectangular package structure. In one embodiment, for example, the aspect ratio of the semiconductor light-emitting element can be 2:1 or more, which is applicable to the packaging structure 7 of the light-emitting element.
第9圖顯示一顯示器裝置示意圖。顯示器裝置包含框架40、側投式背光模組200以及液晶面板(liquid crystal panel)90。側投式背光模組200包含反射膜片80、導光板70、載板22、複數個發光元件封裝結構7及光學擴散片46。複數個發光元件封裝結構7以及電路結構(圖未示)設置於載板22上,電路結構用以控制發光元件封裝結構7。發光元件封裝結構7相對於導光板70之一側邊,當發光元件封裝結構7發光且其光線R從導光板70之所述之側邊進入導光板70,導光板70會改變光線R的方向而使光朝向光學擴散片46,以提供均勻的光源至位於光學擴散片46上方的液晶面板90。於本實施例中,包含有前述半導體發光元件10的發光元件封裝結構7應用於背光模組200,且半導體發光元件10包含前述第二例示之布拉格反射結構101,具有較集中的發光角度。由第9圖可知,當發光元件封裝結構7所發出的光R,在Z軸方向上的強度越強及/或在Z軸方向上的發光角度越集中時,可提升側投式背光模組200之亮度。FIG. 9 shows a schematic diagram of a display device. The display device includes a frame 40 , a side-projection backlight module 200 and a liquid crystal panel 90 . The side-projection backlight module 200 includes a reflective film 80 , a light guide plate 70 , a carrier plate 22 , a plurality of light-emitting element packaging structures 7 and an optical diffusion sheet 46 . A plurality of light-emitting element packaging structures 7 and a circuit structure (not shown) are disposed on the carrier board 22 , and the circuit structure is used to control the light-emitting element packaging structure 7 . The light-emitting element package structure 7 is opposite to one side of the light guide plate 70. When the light-emitting element package structure 7 emits light and its light R enters the light guide plate 70 from the side of the light guide plate 70, the light guide plate 70 will change the direction of the light R. The light is directed toward the optical diffuser 46 to provide a uniform light source to the liquid crystal panel 90 located above the optical diffuser 46 . In this embodiment, the light-emitting element packaging structure 7 including the aforementioned semiconductor light-emitting element 10 is applied to the backlight module 200, and the semiconductor light-emitting element 10 includes the Bragg reflection structure 101 of the aforementioned second example, which has a relatively concentrated light-emitting angle. It can be seen from FIG. 9 that when the light R emitted by the light-emitting element packaging structure 7 is stronger in the Z-axis direction and/or the light-emitting angle in the Z-axis direction is more concentrated, the side-projection backlight module can be improved. 200 brightness.
本申請案所揭示之側投式背光模組200並不限於使用前述包含有半導體發光元件10的發光元件封裝結構7。於其他實施例中,側投式背光模組200可使用包含有前述半導體發光元件20或30的發光元件封裝結構,半導體發光元件20或30可以覆晶形式封裝於發光元件封裝結構內,且半導體發光元件20或30同樣包含前述第二例示布拉格反射結構101。如此一來,可以得到相同的效果。The side-projection type backlight module 200 disclosed in this application is not limited to using the aforementioned light-emitting element packaging structure 7 including the semiconductor light-emitting element 10 . In other embodiments, the side-projection backlight module 200 may use a light-emitting element packaging structure including the aforementioned semiconductor light-emitting element 20 or 30, and the semiconductor light-emitting element 20 or 30 may be packaged in the light-emitting element packaging structure in a flip-chip form, and the semiconductor light-emitting element The light emitting element 20 or 30 also includes the aforementioned second exemplary Bragg reflection structure 101 . In this way, the same effect can be obtained.
第10圖顯示一顯示器裝置截面示意圖。顯示器裝置包含一直下式背光模組300以及一液晶面板90’。直下式背光模組300包含一反射膜片60、光學膜片46’(例如包含擴散片、稜鏡片等)、複數個發光元件封裝結構8設置於反射膜片60上。於本實施例中,發光元件封裝結構8包含前述半導體發光元件10,且半導體發光元件10包含前述第一示例布拉格反射結構101,具有較發散的發光角度。發光元件封裝結構8發出光線R’,且光線R’從光學膜片46’之入光面射入,光學膜片46’使光線R’均勻分散,為其上方的液晶面板90’提供均勻的背光源。由第10圖可知,當發光元件封裝結構8所發出的光R’具有較廣的發光角度時,可使得光學膜片46’的光擴散得更有效率,得到更均勻的背光源。於其他實施例中,本揭露所揭示之直下式背光模組300可使用包含有前述半導體發光元件20或30的發光元件封裝結構,半導體發光元件20或30可用覆晶形式封裝於發光元件封裝結構內,且半導體發光元件20或30包含前述第一示例布拉格反射結構101。此外,上述的發光元件封裝結構可直接用半導體發光元件10、20或30置換,不需要另外封裝,如此一來,亦可以得到相同的效果。FIG. 10 shows a schematic cross-sectional view of a display device. The display device includes a direct-type backlight module 300 and a liquid crystal panel 90'. The direct-type backlight module 300 includes a reflective film 60 , an optical film 46 ′ (for example, including a diffusion film, an optical film, etc.), and a plurality of light-emitting element packaging structures 8 are disposed on the reflective film 60 . In this embodiment, the light-emitting element packaging structure 8 includes the aforementioned semiconductor light-emitting element 10 , and the semiconductor light-emitting element 10 includes the aforementioned first exemplary Bragg reflection structure 101 , which has a more divergent light-emitting angle. The light-emitting element packaging structure 8 emits light R', and the light R' enters from the light-incident surface of the optical film 46', and the optical film 46' disperses the light R' evenly to provide a uniform light for the liquid crystal panel 90' above it. Backlight. It can be seen from FIG. 10 that when the light R' emitted by the light-emitting element packaging structure 8 has a wider light-emitting angle, the light of the optical film 46' can be diffused more efficiently, and a more uniform backlight can be obtained. In other embodiments, the direct type backlight module 300 disclosed in this disclosure can use the light emitting element packaging structure including the aforementioned semiconductor light emitting element 20 or 30, and the semiconductor light emitting element 20 or 30 can be packaged in the light emitting element packaging structure in the form of flip chip , and the semiconductor light emitting element 20 or 30 includes the aforementioned first exemplary Bragg reflection structure 101 . In addition, the above-mentioned packaging structure of the light-emitting element can be directly replaced by the semiconductor light-emitting element 10, 20 or 30 without additional packaging. In this way, the same effect can also be obtained.
上述實施例僅為例示性說明本申請案之原理及其功效,而非用於限制本申請案。任何本申請案所屬技術領域中具有通常知識者在不違背本申請案之技術原理及精神的情況下,對上述實施例進行之各式修改及變化,仍屬於本申請案之範圍。The above-mentioned embodiments are only illustrative to illustrate the principles and functions of the present application, and are not intended to limit the present application. Various modifications and changes made to the above-mentioned embodiments by anyone with ordinary knowledge in the technical field of the application without violating the technical principle and spirit of the application still belong to the scope of the application.