White light emitting structure

Abstract

The invention discloses a white light emitting structure which comprises a blue light emitting diode, a reflecting structure, a yellow light conversion element and a yellow light filtering element. The reflection structure comprises a groove, and the blue light-emitting diode is overlapped with the groove. The yellow light conversion element is located above the blue light emitting diode and is configured to convert a part of blue light emitted by the blue light emitting diode into yellow light. The yellow filtering element is located on the yellow light conversion element. In a first direction perpendicular to the light-emitting surface of the blue light-emitting diode, the bottom surface, facing the blue light-emitting diode, of the yellow light conversion element is overlapped with one part of the blue light-emitting diode and is not overlapped with the other part of the blue light-emitting diode.

Description

Technical Field

[0001] The invention relates to a white light emitting structure. Background Art

[0002] White light emitting components have important application value in modern display technology due to their high brightness characteristics. They are particularly suitable as monochrome displays for outdoor indications, traffic information displays, and vehicle exterior indicator lights. Their advantage is that they can adapt to various ambient light conditions, especially in outdoor high-brightness environments, and can still provide clear and visible indication effects.

[0003] The methods to achieve white light mainly include mixing RGB micro light-emitting diodes (μLEDs) and using white μLEDs. The RGB mixing method generates white light by adjusting the ratio of red, green, and blue, but requires a large number of RGB μLEDs, which increases system complexity and cost, and may cause color deviation due to the difference in the lifespan of RGB μLEDs. White μLEDs can directly generate white light, but the current efficiency of white μLEDs is low, and further optimization of materials and manufacturing technology is needed to improve its efficiency. Summary of the invention

[0004] The present invention provides a white light emitting structure, which has high luminous efficiency and can effectively reduce external light interference, thereby improving the stability and quality of display effects.

[0005] At least one embodiment of the present invention provides a white light emitting structure, comprising a blue light emitting diode, a reflective structure, a yellow light conversion element, and a yellow filter element. The reflective structure comprises a groove, and the blue light emitting diode overlaps the groove. The yellow light conversion element is located above the blue light emitting diode, and is configured to convert a portion of the blue light emitted by the blue light emitting diode into yellow light. The yellow filter element is located above the yellow light conversion element. In a first direction perpendicular to the light emitting surface of the blue light emitting diode, the yellow light conversion element overlaps a portion of the blue light emitting diode toward the bottom surface of the blue light emitting diode, and does not overlap another portion of the blue light emitting diode.

[0006] At least one embodiment of the present invention provides a white light emitting structure, comprising a blue light emitting diode, a reflective structure, a yellow light conversion element, and a light shielding layer. The reflective structure comprises a groove, and the blue light emitting diode overlaps the groove. The yellow light conversion element is located above the blue light emitting diode, and is configured to convert the blue light emitted by the blue light emitting diode into white light. In a first direction perpendicular to the light emitting surface of the blue light emitting diode, the yellow light conversion element covers the entire blue light emitting diode. The light shielding layer is located above the yellow light conversion element, and comprises at least one first opening. The at least one first opening does not overlap the yellow light conversion element in the first direction.

[0007] Based on the above, the combination of blue LED and yellow light conversion element has the advantage of high light emitting efficiency, and the yellow filter element or light shielding layer helps to prevent the external light from irradiating the yellow light conversion element and causing color deviation. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] Figure 1A is a cross-sectional schematic diagram of a white light emitting structure according to an embodiment of the present invention;

[0009] Figure 1B yes Figure 1A A schematic top view of a white light emitting structure;

[0010] FIG. 2A to FIG. 2E yes Figure 1A as well as Figure 1B Schematic cross-sectional view of various stages of a method for manufacturing a white light emitting structure;

[0011] Figure 3A is a cross-sectional schematic diagram of a white light emitting structure according to an embodiment of the present invention;

[0012] Figure 3B yes Figure 3A A schematic top view of a white light emitting structure;

[0013] Figure 4A is a cross-sectional schematic diagram of a white light emitting structure according to an embodiment of the present invention;

[0014] Figure 4B yes Figure 4A A schematic top view of a white light emitting structure;

[0015] Figure 5A is a cross-sectional schematic diagram of a simulated structure of a white light emitting structure according to an embodiment of the present invention;

[0016] Figure 5B yes Figure 5A A schematic top view of a white light emitting structure;

[0017] Fig. 6A is a cross-sectional schematic diagram of a white light emitting structure according to an embodiment of the present invention;

[0018] Figure 6B yes Fig. 6A A schematic top view of a white light emitting structure;

[0019] 7A to 7E yes Fig. 6A as well as Figure 6B Schematic cross-sectional view of various stages of a method for manufacturing a white light emitting structure;

[0020] Figure 8is a cross-sectional schematic diagram of a white light emitting structure according to an embodiment of the present invention;

[0021] Fig. 9 It is a cross-sectional schematic diagram of a white light emitting structure according to an embodiment of the present invention.

[0022] Explanation of symbols

[0023] 10A, 10B, 10C, 10D, 10E, 10F: White light emitting structure

[0024] 100: Circuit board

[0025] 110: pad

[0026] 200: Blue LED

[0027] 202: Bright surface

[0028] 210: Electrode

[0029] 220:Semiconductor stacking

[0030] 310: Reflective Structure

[0031] 312: Groove

[0032] 312b: bottom

[0033] 312s: Sidewall

[0034] 312s1: first side wall

[0035] 312s2: Second side wall

[0036] 320A, 320B, 320C, 320D: Transparent structure

[0037] 321,331: Bottom surface

[0038] 322,332,342:Through hole

[0039] 330A, 330B, 330C, 330D: Yellow light conversion element

[0040] 340A, 340B, 340C: Yellow filter element

[0041] 350: Light-shielding layer

[0042] 352: First Opening

[0043] 360: Reflective layer

[0044] 362: Second opening

[0045] D1: First direction DETAILED DESCRIPTION

[0046] Figure 1A is a cross-sectional schematic diagram of a white light emitting structure 10A according to an embodiment of the present invention. Figure 1B yes Figure 1A A schematic top view of a white light emitting structure 10A, wherein Figure 1A correspond Figure 1B Line A-A' position. Please refer to Figure 1A and Figure 1B The white light emitting structure 10A includes a blue light emitting diode 200 , a reflective structure 310 , a yellow light conversion element 330A and a yellow filter element 340A. In this embodiment, the white light emitting structure 10A further includes a transparent structure 320A and a light shielding layer 350 .

[0047] The blue light emitting diode 200 is, for example, a micro light emitting diode and is disposed on the circuit substrate 100. In some embodiments, the blue light emitting diode 200 includes a semiconductor stack 220 and a plurality of electrodes 210 located on the semiconductor stack 220. In some embodiments, the semiconductor stack 220 includes an N-type semiconductor (not shown separately in the figure), a P-type semiconductor (not shown separately in the figure), and a light emitting layer (not shown separately in the figure) located between the N-type semiconductor and the P-type semiconductor, and the two electrodes 210 contact the N-type semiconductor and the P-type semiconductor, respectively. Although in the present embodiment, the two electrodes 210 are located on the same side of the semiconductor stack 220, the present invention is not limited thereto. In other embodiments, the two electrodes 210 are located on different sides of the semiconductor stack 220, respectively. In other words, the blue light emitting diode 200 may be a horizontal light emitting diode or a vertical light emitting diode.

[0048] The electrode 210 of the blue light emitting diode 200 is bonded to the pad 110 of the circuit substrate 100. In some embodiments, the electrode 210 is bonded to the pad 110 by conductive glue, solder or other suitable structures.

[0049] The reflective structure 310 is located on the circuit substrate 100 and surrounds the blue LED 200 . The reflective structure 310 includes a groove 312 , and the blue LED 200 overlaps the groove 312 .

[0050] In the present embodiment, the reflective structure 310 includes a white insulating material, for example, a photoresist material and reflective particles dispersed in the photoresist material. In the present embodiment, the reflective structure 310 contacts the blue light emitting diode 200. For example, the blue light emitting diode 200 is partially embedded in the reflective structure 200. The reflective structure 200 contacts and surrounds the electrode 210 of the blue light emitting diode 200, and the reflective structure 200 is located between the semiconductor stack 220 and the circuit substrate 100. In other embodiments, the reflective structure 310 includes a conductive material, and the reflective structure 310 is separated from the blue light emitting diode 200.

[0051] In the present embodiment, the groove 312 of the reflective structure 310 includes a sidewall 312s and a bottom surface 312b, and the blue LED 200 protrudes from the bottom surface 312b of the groove 312. In the present embodiment, the reflective structure 310 covers a portion of the sidewall of the semiconductor stack 220 of the blue LED 200, while another portion of the sidewall of the semiconductor stack 220 is not covered by the reflective structure 310, but the present invention is not limited thereto. In other embodiments, the reflective structure 310 covers the entire sidewall of the semiconductor stack 220.

[0052] In this embodiment, the top surface of the blue LED 200 facing away from the circuit substrate 100 is defined as the light emitting surface 202 , and the reflective structure 310 exposes the light emitting surface 202 of the blue LED 200 .

[0053] The transparent structure 320A and the yellow light conversion element 330A are located on the blue LED 200. In some embodiments, the transparent structure 320A and the yellow light conversion element 330A are located on the light emitting surface 202 of the blue LED 200 and contact the light emitting surface 202 of the blue LED 200.

[0054] The transparent structure 320A and the yellow light conversion element 330A are located in the groove 312 of the reflective structure 310. In some embodiments, the yellow light conversion element 330A contacts the sidewall 312s and the bottom surface 312b of the groove 312, and the transparent structure 320A is separated from the sidewall 312s and the bottom surface 312b. In this embodiment, the yellow light conversion element 330A surrounds the blue LED 200 and the transparent structure 320A, and the yellow light conversion element 330A contacts the sidewall of the blue LED 200 and the sidewall of the transparent structure 320A.

[0055] In some embodiments, the yellow light conversion element 330A includes a yellow light conversion material, such as a quantum dot material, a phosphorescent material, a fluorescent material, a dye, a perovskite material, or other suitable materials. In some embodiments, the yellow light conversion element 330A also includes a polymer material, and the yellow light conversion material is dispersed in the polymer material. In some embodiments, the polymer material includes a photoresist material or other suitable materials.

[0056] In the present embodiment, in the first direction D1 perpendicular to the light emitting surface 202 of the blue LED 200, the bottom surface 331 of the yellow light conversion element 330A facing the blue LED 200 overlaps a portion of the blue LED 200, and does not overlap another portion of the blue LED 200. In the present embodiment, the bottom surface 321 of the transparent structure 320A overlaps the aforementioned another portion of the blue LED 200 in the first direction D1.

[0057] The yellow filter element 340A is located above the yellow light conversion element 330A and the reflective structure 310. In this embodiment, the yellow filter element 330A surrounds the transparent structure 320A, and the transparent structure 320A passes through the yellow light conversion element 330A and the yellow filter element 340A. For example, the transparent structure 320A is located in the through hole 332 of the yellow light conversion element 330A and the through hole 342 of the yellow filter element 340A, and the yellow filter element 340A exposes the transparent structure 320A.

[0058] The yellow light conversion element 330A is configured to convert a portion of the blue light emitted by the blue LED 200 into yellow light. For example, a portion of the blue light emitted by the blue LED 200 enters the yellow light conversion element 330A from the light emitting surface 202 and excites the yellow light conversion material in the yellow light conversion element 330A, and the yellow light conversion material absorbs the blue light and emits yellow light. The yellow light emitted by the yellow light conversion element 330A further passes through the yellow filter element 340A.

[0059] On the other hand, another part of the blue light emitted by the blue LED 200 enters the transparent structure 320A from the light emitting surface 202. The blue light passing through the transparent structure 320A and the yellow light passing through the yellow filter element 340A are mixed with each other to form white light.

[0060] In this embodiment, the yellow light conversion element 330A is excited by the blue light emitting diode 200 to generate yellow light, which has the advantage of high luminous efficiency. In addition, the yellow filter element 340A is arranged on the yellow light conversion element 330A to effectively prevent the external light (especially the blue light in the external light) from exciting the yellow light conversion element 330A, thereby avoiding the color deviation problem of the light emitted by the white light emitting structure 10A.

[0061] The light shielding layer 350 is located above the reflective structure 310 and has a first opening 352 overlapping the groove 312 in the first direction D1. In some embodiments, the light shielding layer 350 includes a black material and can be referred to as a black matrix. The yellow filter element 340A extends from the top surface of the yellow light conversion element 330A to between the light shielding layer 350 and the reflective structure 310.

[0062] FIG. 2A to FIG. 2E yes Figure 1A as well as Figure 1B The cross-sectional diagram of each stage of the manufacturing method of the white light emitting structure 10A is shown in FIG. Figure 2A , the blue light emitting diode 200 is bonded to the circuit substrate 100 .

[0063] Please refer to Figure 2B , forming a reflective structure 310 on the circuit substrate 100. For example, a material including a photoresist and reflective particles is first coated on the circuit substrate 100 and the blue LED 200, and then the material is exposed and developed to obtain the reflective structure 310 with the blue LED 200 exposed.

[0064] Please refer to Figure 2C , forming a transparent structure 320A on the light emitting surface 202 of the blue LED 200. For example, a photoresist material is first coated on the blue LED 200 and the reflective structure 310, and then the photoresist material is exposed and developed to obtain the transparent structure 320A. In this embodiment, the top surface of the transparent structure 320A exceeds the top surface of the reflective structure 310.

[0065] Please refer to Figure 2D , forming the yellow light conversion element 330A on the light emitting surface 202 of the blue light emitting diode 200. For example, a material including a photoresist and a yellow light conversion material is first coated on the transparent structure 320A, the blue light emitting diode 200 and the reflective structure 310, and then the aforementioned material is subjected to an exposure and development process to obtain the yellow light conversion element 330A. In other embodiments, the yellow light conversion element 330A may also be formed by other methods, such as printing or other suitable manufacturing processes.

[0066] In this embodiment, the transparent structure 320A is first made, and then the yellow light conversion element 330A is filled into the remaining portion of the groove 312 of the reflective structure 310. In this way, even if the manufacturing process resolution of the yellow light conversion element 330A is low, the through hole 332 of the yellow light conversion element 330A can still be aligned with the transparent structure 320A.

[0067] In this embodiment, the top surface of the transparent structure 320A exceeds the top surface of the yellow light conversion element 330A.

[0068] Please refer to Figure 2E , forming a yellow filter element 340A on the yellow light conversion element 330A and the reflective structure 310. For example, the material of the yellow filter element 340A includes photoresist, and the method of forming the yellow filter element 340A includes exposure and development processes. In other embodiments, the yellow filter element 340A may also be formed by other methods, such as printing or other suitable processes.

[0069] In this embodiment, since the transparent structure 320A is made first and then the yellow filter element 340A is formed, the through hole 342 of the yellow filter element 340A can be more accurately aligned with the transparent structure 320A.

[0070] In addition, in this embodiment, since the transparent structure 320A is located at the center of the blue LED 200 in the top view, the generated blue light and yellow light can be more evenly mixed into white light.

[0071] Finally, back to Figure 1A , forming a light shielding layer 350 on the yellow filter element 340A. For example, a material including a photoresist and a light absorbing material is first coated on the transparent structure 320A and the yellow filter element 340A, and then the aforementioned material is subjected to an exposure and development process to obtain the light shielding layer 350. In other embodiments, the light shielding layer 350 may also be formed by other methods, such as printing, physical vapor deposition, chemical vapor deposition, atomic layer deposition or other suitable manufacturing processes.

[0072] Figure 3A is a cross-sectional schematic diagram of a white light emitting structure 10B according to an embodiment of the present invention. Figure 3B yes Figure 3A A schematic top view of a white light emitting structure 10B, wherein Figure 3A correspond Figure 3B The position of line A-A'. It must be noted here that Figure 3A and Figure 3B The implementation examples are used Figure 1A and Figure 1B The component numbers and partial contents of the embodiments are the same, wherein the same or similar numbers are used to represent the same or similar components, and the description of the same technical contents is omitted. The description of the omitted parts can be referred to the aforementioned embodiments, and will not be repeated here.

[0073] Please refer to Figure 3A as well as Figure 3BIn this embodiment, the transparent structure 320B, the yellow light conversion element 330B and the yellow filter element 340B are filled into the groove 312 of the reflective structure 310 .

[0074] The transparent structure 320B and the yellow light conversion element 330B are located on the blue LED 200. In some embodiments, the transparent structure 320B and the yellow light conversion element 330B are located on the light emitting surface 202 of the blue LED 200 and contact the light emitting surface 202 of the blue LED 200.

[0075] In some embodiments, the transparent structure 320B contacts the sidewalls 312s and the bottom surface 312b of the groove 312. The transparent structure 320B is located on at least two sides of the blue LED 200 and is filled between the blue LED 200 and the reflective structure 310. In some embodiments, the transparent structure 320B contacts the sidewalls of the blue LED 200. In some embodiments, the transparent structure 320B surrounds the blue LED 200. In some embodiments, the transparent structure 320B extends between the light shielding layer 350 and the reflective structure 310.

[0076] The yellow filter element 340B is located above the yellow light conversion element 330B. In this embodiment, the transparent structure 320B is located on at least two sides of the yellow light conversion element 330B and at least two sides of the yellow filter element 340B. In other embodiments, the transparent structure 320B surrounds the yellow light conversion element 330B and the yellow filter element 340B. In some embodiments, the transparent structure 320B has a through hole 322, and the yellow light conversion element 330B and the yellow filter element 340B are located in the through hole 322. For example, the through hole 322 is first formed by an exposure process and a development process, and then the yellow light conversion element 330B and the yellow filter element 340B are filled in the through hole 322. In some embodiments, the through hole 322 is, for example, a rectangle, a circle, an ellipse or other geometric shapes. Forming the yellow light conversion element 330B and the yellow filter element 340B by such a method can reduce the difficulty of the manufacturing process and improve the production yield.

[0077] In the present embodiment, in the first direction D1 perpendicular to the light emitting surface 202 of the blue LED 200, the bottom surface 331 of the yellow light conversion element 330B facing the blue LED 200 overlaps a portion of the blue LED 200, and does not overlap another portion of the blue LED 200. In the present embodiment, the bottom surface 321 of the transparent structure 320B facing the blue LED overlaps the aforementioned another portion of the blue LED 200 in the first direction D1.

[0078] The yellow light conversion element 330B is configured to convert a portion of the blue light emitted by the blue LED 200 into yellow light. For example, a portion of the blue light emitted by the blue LED 200 enters the yellow light conversion element 330B from the light emitting surface 202 and excites the yellow light conversion material in the yellow light conversion element 330B, and the yellow light conversion material absorbs the blue light and emits yellow light. The yellow light emitted by the yellow light conversion element 330B further passes through the yellow filter element 340B.

[0079] On the other hand, another part of the blue light emitted by the blue LED 200 enters the transparent structure 320B from the light emitting surface 202. The blue light passing through the transparent structure 320B and the yellow light passing through the yellow filter element 340B are mixed with each other to form white light.

[0080] In this embodiment, the yellow light conversion element 330B is excited by the blue light emitting diode 200 to generate yellow light, which has the advantage of high luminous efficiency. In addition, the yellow filter element 340B is arranged on the yellow light conversion element 330B to effectively prevent the external light (especially the blue light in the external light) from exciting the yellow light conversion element 330B, thereby avoiding the color deviation problem of the light emitted by the white light emitting structure 10B.

[0081] Figure 4A is a cross-sectional schematic diagram of a white light emitting structure 10C according to an embodiment of the present invention. Figure 4B yes Figure 4A A schematic top view of a white light emitting structure 10C, wherein Figure 4A correspond Figure 4B The position of line A-A'. It must be noted here that Figure 4A and Figure 4B The implementation examples are used Figure 3A and Figure 3B The component numbers and partial contents of the embodiments are the same, wherein the same or similar numbers are used to represent the same or similar components, and the description of the same technical contents is omitted. The description of the omitted parts can be referred to the aforementioned embodiments, and will not be repeated here.

[0082] Please refer to Figure 4A and Figure 4B , the blue LED 200 overlaps the groove 312 of the reflective structure 310. In this embodiment, the blue LED 200 protrudes from the bottom surface of the groove 312, and part of the sidewall of the blue LED 200 does not contact the reflective structure 310, but the present invention is not limited thereto. Figure 8 As shown in the white light emitting structure 10E, the entire side wall of the blue light emitting diode 200 is covered by the reflective structure 310 .

[0083] Back to Figure 4A and Figure 4B, the transparent structure 320C, the yellow light conversion element 330C and the yellow filter element 340C are filled into the groove 312 of the reflective structure 310 .

[0084] The transparent structure 320C and the yellow light conversion element 330C are located on the blue LED 200. In some embodiments, the transparent structure 320C and the yellow light conversion element 330C are located on the light emitting surface 202 of the blue LED 200 and contact the light emitting surface 202 of the blue LED 200.

[0085] In the present embodiment, the transparent structure 320C and the yellow light conversion element 330C contact the first side wall 312s1 of the groove 312 and the second side wall 312s2 opposite to the first side wall 312s1. The transparent structure 320C and the yellow light conversion element 330C are respectively located on both sides of the blue light emitting diode and are filled between the blue light emitting diode 200 and the reflective structure 310. In some embodiments, a portion of the transparent structure 320C is laterally located between the blue light emitting diode 200 and the first side wall 312s1, and a portion of the yellow light conversion element 330C is laterally located between the blue light emitting diode 200 and the second side wall 312s2. In the present embodiment, by disposing the transparent structure 320C and the yellow light conversion element 330C on opposite sides of the groove 312, the ratio of the blue light emitting area to the yellow light emitting area can be more easily controlled.

[0086] The yellow filter element 340C is located on the yellow light conversion element 330C. In this embodiment, the yellow filter element 340C and the transparent structure 320C extend from the bottom of the first opening 352 to between the light shielding layer 350 and the reflective structure 310 .

[0087] In the present embodiment, in the first direction D1 perpendicular to the light emitting surface 202 of the blue LED 200, the bottom surface 331 of the yellow light conversion element 330C facing the blue LED 200 overlaps a portion of the blue LED 200, and does not overlap another portion of the blue LED 200. In the present embodiment, the bottom surface 321 of the transparent structure 320C facing the blue LED 200 overlaps the aforementioned another portion of the blue LED 200 in the first direction D1.

[0088] The yellow light conversion element 330C is configured to convert a portion of the blue light emitted by the blue LED 200 into yellow light. For example, a portion of the blue light emitted by the blue LED 200 enters the yellow light conversion element 330C from the light emitting surface 202 and excites the yellow light conversion material in the yellow light conversion element 330C, and the yellow light conversion material absorbs the blue light and emits yellow light. The yellow light emitted by the yellow light conversion element 330C further passes through the yellow filter element 340C.

[0089] On the other hand, another part of the blue light emitted by the blue LED 200 enters the transparent structure 320C from the light emitting surface 202. The blue light passing through the transparent structure 320C and the yellow light passing through the yellow filter element 340C are mixed with each other to form white light.

[0090] In this embodiment, the yellow light conversion element 330C is excited by the blue light emitting diode 200 to generate yellow light, which has the advantage of high luminous efficiency. In addition, the yellow filter element 340C is arranged on the yellow light conversion element 330C to effectively prevent the external light (especially the blue light in the external light) from exciting the yellow light conversion element 330C, thereby avoiding the color deviation problem of the light emitted by the white light emitting structure 10C.

[0091] In some embodiments, the CIE coordinates of the white light emitted by the white light emitting structure 10C are changed by adjusting the area ratio of the transparent structure 320C and the yellow filter element 340C. Figure 5A and Figure 5B The blue LED 200 has a length L and a width W. The ratio of the area of ​​the blue LED 200 overlapping the transparent structure 320C and the area of ​​the blue LED 200 overlapping the yellow filter element 340C is adjusted to change the CIE coordinates of the white light emitted by the white light emitting structure 10C. In the length L of the blue LED 200, the length L1 overlaps the transparent structure 320C, and the blue light will pass through this area; and the length L2 overlaps the yellow light conversion element 330C and the yellow filter element 340C, and the yellow light will pass through this area.

[0092] Taking the length L as 40 microns and the width W as 20 microns as an example, the CIE coordinates of blue light, yellow light, and white light obtained by mixing blue light and yellow light are obtained by adjusting the length L1 and the length L2 as shown in Table 1. In the embodiment of Table 1, the yellow filter element 340C filters out most of the light with a wavelength below 510 nm.

[0093] Table 1

[0094]

[0095]

[0096] It can be seen from Table 1 that when the area ratio of the blue LED 200 overlapping the transparent structure 320C is 16.1% to 26.1%, good white light emitting efficiency can be obtained. In addition, in some embodiments, using a larger blue LED 200 can reduce the impact of design tolerance on color and brightness.

[0097] Fig. 6Ais a cross-sectional schematic diagram of a white light emitting structure 10D according to an embodiment of the present invention. Figure 6B yes Fig. 6A A schematic top view of a white light emitting structure 10D, wherein Fig. 6A correspond Figure 6B The position of line A-A'. It must be noted here that Fig. 6A and Figure 6B The implementation examples are used Figure 1A and Figure 1B The component numbers and partial contents of the embodiments are the same, wherein the same or similar numbers are used to represent the same or similar components, and the description of the same technical contents is omitted. The description of the omitted parts can be referred to the aforementioned embodiments, and will not be repeated here.

[0098] Please refer to Fig. 6A and Figure 6B The white light emitting structure 10D includes a blue light emitting diode 200 , a reflective structure 310 , a yellow light conversion element 330D and a light shielding layer 350 . In this embodiment, the white light emitting structure 10D further includes a transparent structure 320D and a reflective layer 360 .

[0099] The blue LED 200 overlaps the groove 312 of the reflective structure 310. In this embodiment, the blue LED 200 protrudes from the bottom surface of the groove 312, and part of the sidewall of the blue LED 200 does not contact the reflective structure 310, but the present invention is not limited thereto. Fig. 9 As shown in the white light emitting structure 10F, the entire side wall of the blue light emitting diode 200 is covered by the reflective structure 310 .

[0100] Back to Fig. 6A and Figure 6B , the yellow light conversion element 330D is located in the groove 312 of the reflective structure 310 and is located above the blue light emitting diode 200. In the present embodiment, in the first direction D1 perpendicular to the light emitting surface 202 of the blue light emitting diode 200, the yellow light conversion element 330D covers the entire light emitting surface 202 of the blue light emitting diode 200. In the present embodiment, the yellow light conversion element 330D is configured to convert the blue light emitted by the blue light emitting diode 200 into white light. For example, the blue light emitted by the blue light emitting diode 200 partially excites the yellow light conversion element 330D in the yellow light conversion element 330D and generates yellow light, and the yellow light is mixed with the blue light of the blue light emitting diode 200 passing through the yellow light conversion element 330D to form white light.

[0101] The light shielding layer 350 is located on the yellow light conversion element 330D and includes at least one first opening 352 . The first opening 352 does not overlap the yellow light conversion element 330D in the first direction D1 , so that the white light can pass through the light shielding layer 350 through the first opening 352 .

[0102] In the present embodiment, the reflective layer 360 is located between the light shielding layer 350 and the yellow light conversion element 330D and between the light shielding layer 350 and the reflective structure 310. The reflective layer 360 overlaps the light emitting surface 202 of the blue light emitting diode 200 and the yellow light conversion element 330D in the first direction D1. The reflective layer 360 has at least one second opening 362 overlapping the first opening 352. A portion of the groove 352 does not overlap the yellow light conversion element 330D, the reflective layer 360 and the light shielding layer 350, and overlaps the first opening 352 and the second opening 362.

[0103] In some embodiments, the transparent structure 320D is located in the groove 312 and fills the portion of the groove 312 that is not filled by the yellow light conversion element 330D. The transparent structure 320D overlaps the first opening 352 and the second opening 362 and is laterally located between the yellow light conversion element 330D and the reflective structure 310. The transparent structure 320D contacts the sidewall of the yellow light conversion element 330D, the sidewall 312s of the groove 312, and the sidewall of the second opening 362. In other embodiments, the transparent structure 320D extends beyond the reflective layer 360 and contacts the sidewall of the first opening 352. In some embodiments, a portion of the transparent structure 320D is laterally located between the blue light emitting diode 200 and the reflective structure 310.

[0104] In this embodiment, the blue light emitted by the blue LED 200 and / or the yellow light generated by the yellow light conversion element 330D after being excited are reflected by the reflective layer 360, and the light is transmitted to the portion of the groove 312 that is not filled by the yellow light conversion element 330D (i.e., the transparent structure 320D). The blue light and the yellow light are mixed into white light in the yellow light conversion element 330D, and leave the white light emitting structure 10D through the transparent structure 320D, the second opening 362, and the first opening 352.

[0105] In this embodiment, the use of the blue light emitting diode 200 and the yellow light conversion element 330D to generate white light has the advantage of high luminous efficiency. In addition, the light shielding layer 350 is provided on the yellow light conversion element 330D to effectively prevent the external light (especially the blue light in the external light) from exciting the yellow light conversion element 330D, thereby avoiding the color deviation problem of the light emitted by the white light emitting structure 10D. In addition, in this embodiment, there is no need to additionally provide a yellow filter element above the yellow light conversion element 330D.

[0106] 7A to 7E yes Fig. 6A as well as Figure 6B Schematic cross-sectional view of various stages of the manufacturing method of the white light emitting structure 10D. Please refer to Fig. 7A , the blue light emitting diode 200 is bonded to the circuit substrate 100 .

[0107] Please refer to Figure 7B , forming the reflective structure 310 on the circuit substrate 100. For example, a material including a photoresist and reflective particles is first coated on the circuit substrate 100 and the blue light emitting diode 200, and then the material is exposed and developed to obtain the reflective structure 310.

[0108] Please refer to Figure 7C , forming a transparent structure 320D in the groove 312 of the reflective structure 310. For example, a photoresist material is first coated on the blue light emitting diode 200 and the reflective structure 310, and then the photoresist material is exposed and developed to obtain the transparent structure 320D. In this embodiment, the top surface of the transparent structure 320D exceeds the top surface of the reflective structure 310. In this embodiment, the transparent structure 320D exposes the blue light emitting diode 200.

[0109] Please refer to Fig.7D , forming a yellow light conversion element 330D on the blue light emitting diode 200. For example, a material including a photoresist and a yellow light conversion material is first coated on the transparent structure 320D, the blue light emitting diode 200 and the reflective structure 310, and then the aforementioned material is subjected to an exposure and development process to obtain the yellow light conversion element 330D. In other embodiments, the yellow light conversion element 330D may also be formed by other methods, such as printing or other suitable manufacturing processes.

[0110] In this embodiment, the transparent structure 320D is first made, and then the yellow light conversion element 330D is filled into the remaining portion of the groove 312 of the reflective structure 310. In this way, even if the manufacturing process resolution of the yellow light conversion element 330D is low, the yellow light conversion element 330D can still be easily aligned with the transparent structure 320D.

[0111] Please refer to Fig. 7E, forming a reflective layer 360 on the yellow light conversion element 330D and the reflective structure 310. For example, the reflective layer 360 and the reflective structure 310 include the same material, and the method of forming the reflective layer 360 includes an exposure and a development process. In other embodiments, the reflective layer 360 may also be formed by other methods, such as printing, physical vapor deposition, chemical vapor deposition, atomic layer deposition or other suitable processes. In some embodiments, the reflective layer 360 and the reflective structure 310 include different materials, for example, the reflective layer 360 includes a metal layer, and the reflective structure 310 includes a patterned photoresist.

[0112] In this embodiment, since the transparent structure 320D is made first, and then the yellow light conversion element 330D and the reflective layer 360 are formed, the second opening 362 of the reflective layer 360 can be more accurately aligned with the transparent structure 320D.

[0113] Finally, please return to Fig. 6A , forming a light shielding layer 350 on the reflective layer 360. For example, a material including a photoresist and a light absorbing material is first coated on the reflective layer 360, and then the aforementioned material is subjected to an exposure and development process to obtain the light shielding layer 350. In other embodiments, the light shielding layer 350 may also be formed by other methods, such as printing, physical vapor deposition, chemical vapor deposition, atomic layer deposition or other suitable manufacturing processes.

[0114] In summary, the present invention utilizes the advantage of high luminous efficiency of the combination of blue LED and yellow light conversion element, and the yellow filter element or light shielding layer helps to prevent the problem of color deviation caused by external light irradiating the yellow light conversion element.

Claims

1. A white light emitting structure, comprising: Blue LED; A reflective structure including a groove, and the blue light emitting diode overlaps the groove; A yellow light conversion element is located above the blue light emitting diode and is configured to convert a portion of the blue light emitted by the blue light emitting diode into yellow light; as well as A yellow filter element is located above the yellow light conversion element, wherein in a first direction perpendicular to the light emitting surface of the blue LED, a bottom surface of the yellow light conversion element facing the blue LED overlaps a portion of the blue LED and does not overlap another portion of the blue LED.

2. The white light emitting structure according to claim 1, further comprising: A transparent structure overlaps the other portion of the blue LED in the first direction toward the bottom surface of the blue LED, wherein the yellow light conversion element and the transparent structure contact the blue LED.

3. The white light emitting structure according to claim 1, further comprising: The transparent structure is located on the light emitting surface of the blue light emitting diode, and the yellow light conversion element and the yellow light filtering element surround the transparent structure, and the transparent structure passes through the yellow light conversion element and the yellow light filtering element.

4. The white light emitting structure according to claim 1, further comprising: The transparent structure is located on at least two sides of the blue LED, at least two sides of the yellow light conversion element and at least two sides of the yellow filter element, and is filled between the blue LED and the reflective structure.

5. The white light emitting structure according to claim 1, further comprising: A transparent structure, wherein the transparent structure contacts a first side wall of the groove, and the yellow light conversion element contacts a second side wall of the groove opposite to the first side wall.

6. The white light emitting structure according to claim 5, further comprising: a light shielding layer located above the reflective structure and having an opening overlapping the groove in the first direction, wherein the yellow filter element and the transparent structure extend from the bottom of the opening to between the light shielding layer and the reflective structure, wherein at least a portion of the blue light emitting diode is embedded in the reflective structure, and the reflective structure contacts and surrounds an electrode of the blue light emitting diode, wherein a portion of the transparent structure is laterally located between the blue LED and the first side wall, and a portion of the yellow light conversion element is laterally located between the blue LED and the second side wall, In the first direction, the bottom surface of the transparent structure facing the blue LED overlaps the other portion of the blue LED.

7. A white light emitting structure, comprising: Blue LED; A reflective structure including a groove, and the blue light emitting diode overlaps the groove; a yellow light conversion element, located on the blue LED and configured to convert the blue light emitted by the blue LED into white light, wherein in a first direction perpendicular to the light emitting surface of the blue LED, the yellow light conversion element covers the entire blue LED; as well as The light shielding layer is located on the yellow light conversion element and includes at least one first opening, wherein the at least one first opening does not overlap the yellow light conversion element in the first direction.

8. The white light emitting structure according to claim 7, further comprising: The reflective layer is located between the light shielding layer and the yellow light conversion element and overlaps the light emitting surface of the blue light emitting diode in the first direction, wherein a portion of the groove does not overlap the yellow light conversion element, the reflective layer and the light shielding layer.

9. The white light emitting structure according to claim 7, further comprising: The transparent structure is located in the groove and overlaps the at least one first opening of the light shielding layer, wherein the transparent structure is laterally located between the yellow light conversion element and the reflective structure.

10. The white light emitting structure according to claim 9, further comprising: A reflective layer is located between the light shielding layer and the yellow light conversion element and between the light shielding layer and the reflective structure, wherein the reflective layer has at least one second opening, and the at least one second opening overlaps the at least one first opening. wherein the transparent structure contacts the side wall of the yellow light conversion element, the side wall of the groove and the side wall of the at least one second opening; and wherein at least a portion of the blue light emitting diode is embedded in the reflective structure, A portion of the transparent structure is laterally located between the blue light emitting diode and the reflective structure.

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