Organic light-emitting device and manufacturing method thereof

[0044] The present invention will be described in detail below with reference to the specific embodiments shown in the accompanying drawings. However, these embodiments do not limit the present invention, and structural, method, or functional changes made by those skilled in the art according to these embodiments are all included in the protection scope of the present invention.

[0045] Please refer to figure 2 and image 3 , figure 2 It is a schematic structural diagram of a plurality of organic light-emitting devices on the transparent substrate of the present invention; image 3 It is a schematic cross-sectional structure diagram of the organic light-emitting device of the present invention. The organic light emitting device of the present invention includes: a transparent substrate 11 , a light emitting unit 13 , a thin film transistor 12 , a pixel definition layer 14 , a spacer 15 , a package cover 16 and a metal reflection layer 17 . The transparent substrate 11 includes a first surface 111 and a second surface 113 opposite to the first surface 111 , wherein the light emitting unit 13 , the thin film transistor 12 , the pixel definition layer 14 , the spacer 15 , and the package cover 16 are all disposed on the first surface 111 . On the first surface 111 of the transparent substrate 11 , the metal reflective layer 17 is disposed on the second surface 113 of the transparent substrate 11 . By forming the metal reflective layer 17 on the second surface 113 of the transparent substrate 11 , not only the performance of the OLED device can be improved. In addition, it can better achieve the effect of accelerating the heat dissipation of the entire OLED display module, so as to avoid the reduction of the luminous efficiency and the shortening of the service life of the device due to partial heat accumulation.

[0046] In detail, the transparent substrate 11 of the present invention is a glass substrate, and a light-emitting unit 13 is formed on the first surface 111 of the transparent substrate 11 , and the light-emitting unit 13 at least includes red sub-pixels, blue sub-pixels and green sub-pixels. The thin film transistor 12 is disposed on the transparent substrate 11 and is interposed between the first surface 111 and the light emitting unit 13 . In addition, in order to prevent color mixing of different colors between different sub-pixels, a pixel definition layer 14 is provided between two adjacent light-emitting units 13 . The first surface 111 of the transparent substrate 11 is sealed and encapsulated by an encapsulation cover plate 16 , and a spacer 15 for supporting the encapsulation cover plate 16 is further provided between the encapsulation cover plate 16 and the pixel definition layer 14 . In the embodiment of the present invention, the thin film transistor 12 , the light emitting unit 13 , the pixel definition layer 14 and the spacer 15 located on the first surface 111 of the transparent substrate 11 are sealed on the package cover 16 and the transparent substrate 11 through the package cover 16 between. Of course, the organic light-emitting device of the present invention also includes an anode layer, an emission layer, an organic layer cathode layer, etc. These structures are well known to those skilled in the art and will not be described in detail here.

[0047] In particular, a metal reflective layer 17 is formed on the second surface 113 of the transparent substrate 11, and the metal reflective layer 17 is used to reflect the light emitted from the light-emitting unit 13 located on the side of the first surface 111, that is, the light emitted by the organic light-emitting device. Light. During the preparation process, the metal reflective layer 17 may be formed on the second surface 113 of the transparent substrate 11 by means of evaporation, sputtering or electroplating. Preferably, because sometimes the OLED display module has long-term display requirements in certain areas, it is inevitable to generate heat accumulation, which will lead to the reduction of the device efficiency and life of this part, and through the transparent substrate. The metal reflective layer 17 of the present invention is formed on the second surface 113 of the 11, which will dissipate heat from the concentrated place to other areas, so as to avoid the occurrence of the above phenomenon. In addition, in order to achieve good heat dissipation at the same time, the thickness of the metal reflective layer 17 of the present invention is at least 300 nm. By disposing the metal reflective layer 17 on the second surface 113 of the transparent substrate 11, not only the light emitted by the organic light-emitting device can be reflected back, but also the heat can be dissipated from the concentrated place to other areas, so as to dissipate heat for the display module .

[0048] Preferably, the material of the metal reflection layer 17 of the present invention is silver, aluminum or molybdenum or an alloy of any combination thereof, and may also be other heat dissipation materials with better heat dissipation effect. Further, the reflectivity of the metal reflection layer 17 is 80 to 98%. On the one hand, the metal reflective layer 17 can reflect the light reflected at each interface and transmitted to the second surface 113 of the transparent substrate 11 through the light-transmitting material, thereby improving the brightness of the entire organic light-emitting device; on the other hand, The requirement of the light-emitting brightness of the organic light-emitting device is reduced, and the power consumption is also reduced, thereby achieving the effect of energy saving.

[0049] like Figure 4 As shown, in the present invention, a preparation method of an organic light-emitting device is also proposed, and the preparation method includes:

[0050] S11, forming a plurality of organic light-emitting elements 100 on the first surface 111 of the transparent substrate 11;

[0051] S13, forming a metal reflection layer 17 on the second surface 113 of the transparent substrate 11 opposite to the first surface 111;

[0052] S15 , splitting the transparent substrate 11 into a plurality of separated organic light-emitting elements 100 .

[0053] Further, as Figure 5 As shown, before splitting the transparent substrate 11 into a plurality of separated organic light-emitting elements 100 in step S15, it further includes:

[0054] S21, coating photoresist on the metal reflection layer 17;

[0055] S23, exposing and developing the interval regions of each organic light-emitting element 100;

[0056] S25, etching the exposed metal reflective layer 17 in the interval region;

[0057] Specifically, in order to meet the mass production requirements in the industrialized production process, during the preparation process of the organic light-emitting device in the present invention, firstly, a plurality of organic light-emitting elements 100 are arranged on the transparent substrate 11 at intervals, and after the preparation is completed, the plurality of organic light-emitting elements 100 are placed The light-emitting element 100 splits are a plurality of spaced apart organic light-emitting elements 100 . In this embodiment, a metal reflective layer 17 is also formed on the back of the transparent substrate 11. Since the metal reflective layer 17 has a certain thickness, it is necessary to coat the metal reflective layer 17 with photoresist before splitting. The interval area of ​​100 is exposed and developed, and further, the exposed metal reflective layer 17 in the interval area is etched, so as to facilitate the splitting of the transparent substrate 11 in the later stage, and avoid the increase in the splitting process due to the metal reflective layer 17. difficulty.

[0058] In particular, as Image 6 As shown, the specific preparation steps for forming a plurality of organic light-emitting elements 100 on the first surface 111 of the transparent substrate 11 in the present invention S11 are as follows:

[0059] S111, forming the thin film transistor 12 on the first surface 111 of the transparent substrate 11;

[0060] S112, forming the light-emitting unit 13 on the thin film transistor 12;

[0061] S113, forming a pixel definition layer 14 between two adjacent light-emitting units 13;

[0062] S114, forming spacers 15 on the pixel definition layer 14;

[0063] S115 , the thin film transistor 12 , the light emitting unit 13 , the pixel definition layer 14 and the spacer 15 are sealed between the package cover 16 and the transparent substrate 11 by using the package cover 16 .

[0064] In the present invention, for the fabrication of a single organic light-emitting element 100, a light-emitting unit 13 is formed on the first surface 111 of the transparent substrate 11, and the light-emitting unit 13 at least includes red sub-pixels, blue sub-pixels and green sub-pixels. The thin film transistor 12 is provided between the first surface 111 and the light emitting unit 13 . In addition, in order to prevent color mixing of different colors between different sub-pixels, a pixel definition layer 14 is provided between two adjacent light-emitting units 13 . The first surface 111 of the transparent substrate 11 is sealed and packaged by a package cover plate 16 , and the package cover plate 16 seals the devices located on the first surface 111 of the transparent substrate 11 between the transparent substrate 11 and the package cover plate 16 . In particular, a spacer 15 for supporting the package cover plate 16 is further provided between the package cover plate 16 and the pixel definition layer 14 . Preferably, a metal reflection layer 17 is formed on the back surface of the transparent substrate 11 , and the metal reflection layer 17 emits the light emitted by the light emitting unit 13 located on the first surface 111 back. In the present invention, in order to achieve better heat dissipation effect, the thickness of the metal reflective layer 17 is at least 300 nm. In particular, the reflectivity of the metal reflective layer 17 is 80% to 98%, which is set so that the organic light emitting device of the present invention can improve the brightness of the entire display module. Preferably, in the present invention, the material of the metal reflective layer 17 is silver, aluminum or molybdenum or an alloy of any combination thereof.

[0065] The present invention provides an organic light-emitting device and a preparation method thereof. A metal reflective layer is arranged on the back of the transparent substrate to improve the light extraction efficiency of the OLED device and enhance the brightness of the OLED display module. The heat dissipation enhances the heat dissipation effect of the OLED display module and avoids the reduction of the luminous efficiency and life of the device due to heat accumulation.

[0066] The present invention has been described in detail above with reference to the embodiments of the accompanying drawings, and those skilled in the art can make various modifications to the present invention according to the above description. Therefore, some details in the embodiments should not be construed to limit the present invention, and the present invention will take the scope defined by the appended claims as the protection scope of the present invention.