[0030] In order to make the purpose, technical solutions and effects of this application clearer and clearer, the following further describes this application in detail with reference to the drawings and embodiments.
[0031] The present invention provides a silicon-based micro display screen and a preparation method thereof, which are mainly used to solve the problems of the physical limitation of the existing OLED evaporation patterning technology and the difficulty of high pixel density patterning.
[0032] Such as figure 1 As shown, the silicon-based micro display screen includes: a driving backplane 10, a pixel definition layer 20 formed on the driving backplane 10, a light-emitting layer 21 formed in the pixel definition layer 20, and a encapsulation device. The encapsulation layer 60 of the light-emitting layer 21 and the metal reflective layer 50 formed between the light-emitting layer 21 and the encapsulation layer 60.
[0033] The driving backplane 10 includes a silicon substrate 12 and an anode layer 22 formed on one side of the silicon substrate 12. The light-emitting layer 21 is formed in the pixel defining layer 20 by electrofluid printing and is located on the anode. Above layer 22.
[0034] Specifically, the silicon substrate 12 is provided with a plurality of regularly arranged vias 11, the anode layer 22 includes a plurality of anode units arranged in a pixel pattern, and each anode unit is connected to the corresponding via 11 one by one. Correspondingly, the anode unit is an indium tin oxide film (ITO). In this embodiment, the width of the anode unit is 5 microns, but it should not be limited to this.
[0035] The pixel definition layer 20 is formed by a yellow light process and an etching process, and the anode layer 22 is exposed to the pixel definition layer 20. Preferably, the pixel definition layer 20 is made of SiO 2 The photolithography mask is a material, and a film is formed on the silicon substrate 12 and the anode layer 22.
[0036] The light emitting layer 21 includes an organic light emitting layer, a hole injection layer and a hole transport layer located between the anode layer 22 and the organic light emitting layer, and an electron injection layer and an electron transport layer located between the cathode layer and the organic light emitting layer. Further, the hole transport layer is located between the organic light emitting layer and the hole injection layer; the electron transport layer is located between the organic light emitting layer and the electron injection layer.
[0037] The light-emitting layer 21 includes sub-pixels spaced apart from each other. The sub-pixels include a first sub-pixel 211, a second sub-pixel 212, and a third sub-pixel 213, and the distance between two adjacent sub-pixels is 8 microns. Specifically, the first sub-pixel 211 is an OLED that can emit red light R, the second sub-pixel 212 is an OLED that can emit green light G, and the third sub-pixel 213 is an OLED that can emit blue light B. Thus, RGB three-color display can be realized.
[0038] The metal reflective layer 50 is formed on the upper surface of the light-emitting layer 21 and the pixel definition layer 20, and the metal reflective layer 50 is also formed between two adjacent sub-pixels, so as to avoid the interference between the two adjacent sub-pixels. Optical crosstalk. In the present invention, the metal reflective layer 50 is an Al reflective layer and can be used as the cathode layer of the light-emitting layer 21.
[0039] The packaging layer 60 includes a thin film packaging layer 61, and the thin film packaging layer 61 completely covers the metal reflective layer 50. The packaging layer 60 also includes a glass cover plate 63 encapsulated on the top of the thin film packaging layer 61 and completely covering the thin film packaging layer 61. Specifically, the glass cover plate 63 is fixedly connected to the thin film encapsulation layer 61 through UV glue 62.
[0040] The thin film encapsulation layer 61 may be an organic thin film, an inorganic thin film, or an inorganic thin film stacked on an organic thin film.
[0041] Such as Figure 1 to Figure 6 As shown, the manufacturing method of silicon-based microdisplay mainly includes the following steps:
[0042] S1: A silicon substrate 12 is provided, and an anode layer 22 is vapor-deposited on the silicon substrate 12 to form the driving backplane 10; at this time, each anode unit of the anode layer 22 is connected to the corresponding via 11 one by one Corresponding, specifically as figure 2 Shown.
[0043] S2: Plating a film on the silicon substrate 12 and the anode layer 22 to form a pixel definition layer 20; at this time, the pixel definition layer 20 completely covers the silicon substrate 12 and the anode layer 22, specifically as follows image 3 Shown.
[0044] S3: Use yellow light process and etching process to etch the pixel defining layer 20; after the etching, the anode layer 22 is exposed to the pixel defining layer 20, specifically as Figure 4 Shown.
[0045] S4: Using electrofluidic printing technology, a light-emitting layer 21 is formed in the pixel defining layer 20; at this time, the light-emitting layer 21 is formed on the anode layer 22, and the first sub-pixel 211 and the second sub-pixel 212 And the third sub-pixel 213 are respectively formed on the corresponding anode unit, specifically as Figure 5 Shown.
[0046] S5: forming a metal reflective layer 50 on the light emitting layer 21 and the pixel defining layer 20; at this time, the metal reflective layer 50 is not only formed on the light emitting layer 21 and the pixel defining layer 20, but also formed between two adjacent sub-pixels For example, formed between the first sub-pixel 211 and the second sub-pixel 212, and between the second sub-pixel 212 and the third sub-pixel 213, specifically as Image 6 Shown.
[0047] S6: Encapsulate the metal reflective layer 50 to obtain a silicon-based micro display screen; figure 1 Shown.
[0048] The step S6 specifically includes:
[0049] S61: Using thin film packaging technology to form a thin film packaging layer 61 on the metal reflective layer 50;
[0050] S62: Use a glass cover plate 63 to encapsulate the thin-film packaging layer 61, and use UV glue 62 to fix the thin-film packaging layer 61 above the thin-film packaging layer 61.
[0051] In summary, the present invention ① uses the high-resolution drive backplane 10 to realize the preparation of high-resolution display screens of 1000 ppi and above; ② realizes high-ppi micro-display graphics through yellow light process and etching process , Breaking through the physical limit of high-pixel-density high-precision metal masks, can achieve 2000 and higher pixel density display, and in the use of raw materials, it saves about 90% compared with evaporation technology; ③printing by electrofluid Technology printing small-size RGB three-color OLED can realize the RGB three-color display of silicon-based micro-display; ④The metal reflective layer 50 is formed between the light-emitting layer 21 and the encapsulation layer 60, which can prevent two adjacent sub-pixels Light crosstalk occurs between.
[0052] The above are only specific embodiments of the present invention, but the protection scope of the present invention is not limited to this. Anyone familiar with the technology can understand the changes or substitutions that are conceivable within the technical scope disclosed in the present invention. All should be covered within the scope of the present invention. Therefore, the protection scope of the present invention should be subject to the protection scope of the claims.