CN100499953C - A packaging method of organic electroluminescent display - Google Patents

Abstract

The invention discloses a packaging method of an organic electroluminescent display which can significantly improve the service life of the device: firstly, an ITO conductive layer, a hole transport layer, a light-emitting layer, an electronic The transmission layer and the cathode layer, the cathode layer is set to lead out the conductor diaphragm connected to the negative pole of the DC voltage, and then a layer of thin film packaging is formed on the surface of the cathode layer by vacuum evaporation, particle sputtering or magnetron sputtering layer, the thin film encapsulation layer simultaneously seals the side edges of the hole transport layer, the light emitting layer, the electron transport layer and the cathode layer.

Description

A kind of packaging method of organic electroluminescence display

technical field

The invention relates to a packaging method for an organic electroluminescence display.

Background technique

With the improvement of people's visual requirements and the rapid development of display technology, it has become a situation where a hundred flowers are blooming, from cathode ray tube display (CRT), liquid crystal display (LCD), plasma display (PDP) to organic electroluminescent display (OLED) And Electroluminescent Display (FED), to name a few. With the rapid development of science and technology, a revolution is also taking place in the field of display technology, and various new flat panel display technologies (FPD) have emerged as the times require. Cathode ray tube display (CRT) has the shortcomings of large size, high power consumption and radiation, and gradually loses its dominance in the display field; flat panel display technology is known as a rising technology and is the mainstream of display technology development in the 21st century , and thus has been widely valued by people, it must not only have perfect display quality, but also need more improvements in volume, energy saving and other aspects. LCD, PDP and OLED are the three mainstreams of flat panel display. OLED display devices, including PLED (polymer organic electroluminescent display), have greater advantages compared with other display devices, specifically manifested in low operating voltage and low production cost. , low energy consumption, thinner, higher brightness and clarity. Flexible display is one of the development directions of OLED/PLED display devices, but the lifespan of OLED flat panel display devices is affected due to the existing problems in packaging technology.

The lifespan of an OLED device depends on the selected organic material on the one hand, and on the other hand the packaging method of the device; because the organic material is very unstable, if the OLED device is not well packaged, the organic material will be mixed with the water vapor in the vacuum chamber. , Oxygen and other gases react, and it is easy to fail, resulting in a reduction in the lifetime of the entire OLED device. Therefore, in order to suppress the degradation and failure of the OLED in the long-term working process and achieve a sufficient service life in stable operation, there is a high requirement for the barrier property of the packaging material.

Contents of the invention

In order to solve the problem of low service life of OLED/PLED display devices, the present invention provides a packaging method for organic electroluminescent displays that can significantly improve device service life.

To achieve the above object, the present invention is achieved by taking the following technical solutions:

A method for encapsulating an organic electroluminescent display, characterized in that an ITO conductive layer, a hole transport layer, a light-emitting layer, an electron transport layer and a cathode layer are successively arranged on the upper surface of a glass substrate from bottom to top, and the cathode layer The layer is set to lead out the conductor diaphragm connected to the negative pole of the DC voltage, and then a layer of thin film encapsulation layer is formed on the surface of the cathode layer by vacuum evaporation, particle sputtering or magnetron sputtering, and the thin film encapsulation layer simultaneously absorbs holes The transport layer, emissive layer, electron transport layer and cathode layer are side-sealed.

In the above scheme, the thin film encapsulation layer is formed by vacuum evaporation, particle sputtering or magnetron sputtering processes using relatively stable materials such as selenium, tellurium, and antimony in the air; the vacuum degree during vacuum evaporation is 1× 10 ^-3 Pa or less, and the vacuum deposition thickness is 80 nm or more. The cathode layer is made of metal aluminum or calcium/aluminum, magnesium/silver low work function material.

The present invention prepares a dense, non-oxidizable thin-film encapsulation layer on the outside of the OLED/PLED cathode by vacuum evaporation, particle sputtering, magnetron sputtering and other film-forming methods under high vacuum conditions, so as to realize the encapsulation of the display device. Reduce the erosion of water, oxygen, etc. on the inside of the device, form an effective protection for the cathode and organic materials, suppress the degradation and failure of the OLED during long-term operation, and achieve stable operation to achieve sufficient life.

Description of drawings

Fig. 1 is a structure diagram of an organic electroluminescent display after being encapsulated by the method of the present invention.

Detailed ways

The present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments.

As shown in Figure 1, a packaging method for an organic electroluminescent display, firstly, an ITO (indium oxide and tin oxide composite film material) conductive layer 5 and a hole transport layer 4 are sequentially arranged on the upper surface of a glass substrate 6 from bottom to top. , luminescent layer (fluorescent material) 3, electron transport layer 2, and cathode layer 1 made of metal aluminum or calcium/aluminum, magnesium/silver and other low work function materials, and then set on the cathode layer 1 to be used for interfacing with the DC voltage negative electrode connected lead-out conductor diaphragm, and then adopt vacuum evaporation, particle sputtering or magnetron sputtering process to form a layer of thin film encapsulation layer 7 on the surface of cathode layer 1. 3. The sides of the electron transport layer 2 and the cathode layer 1 are sealed. The thin-film encapsulation layer 7 can be formed by vacuum evaporation, particle sputtering or magnetron sputtering using materials that are relatively stable in air, such as selenium, tellurium, and antimony. These film materials have good barrier properties to moisture, oxygen, etc.

A specific embodiment of the present invention is to respectively arrange an ITO conductive layer 5, a hole transport layer 4, a light-emitting layer 3, an electron transport layer 2, and an aluminum alloy material on the upper surface of a glass substrate 6 sequentially from bottom to top using a conventional preparation process. Cathode layer 1, and then on the metal cathode 1 in the vacuum chamber, directly use selenium material to form a thin film encapsulation layer 7 by vacuum evaporation process in situ, and the vacuum degree during vacuum evaporation is below 1 × 10 ^-3 Pa; vacuum evaporation The thickness of the rear thin film encapsulation layer 7 is 80 nm. After the packaging is completed, the ITO conductive layer 5 and the cathode layer 1 are respectively connected to the positive and negative electrodes of the DC voltage.

The present invention starts from improving the barrier property of OLED encapsulation and prolonging the service life of OLED devices. After completing the setting of each functional layer, the film encapsulation layer is directly vapor-deposited in situ on the metal cathode in the vacuum chamber, which not only simplifies the production process, but also more effectively prolongs the life of the OLED device. the lifetime of OLED devices.

Claims (3)

1. the method for packing of a display of organic electroluminescence, it is characterized in that, earlier set gradually ITO conductive layer, hole transmission layer, luminescent layer, electron transfer layer and cathode layer from bottom to top at the glass substrate upper surface, described cathode layer is provided for the conductor introduction diaphragm that is connected with the direct voltage negative pole, on the cathode layer surface thin film encapsulated layer is set then, this thin-film encapsulation layer forms by vacuum evaporation, particle sputter or magnetron sputtering technique with the material of one of selenium, tellurium, antimony; Described thin-film encapsulation layer is simultaneously with hole transmission layer, luminescent layer, electron transfer layer and cathode layer side seals.

2. the method for packing of display of organic electroluminescence as claimed in claim 1 is characterized in that, described thin-film encapsulation layer forms by vacuum evaporation process with selenium, and the vacuum degree during vacuum evaporation is 1 X 10 ^-3Below the Pa.

3. the method for packing of display of organic electroluminescence as claimed in claim 2 is characterized in that, the vacuum evaporation thickness of described thin-film encapsulation layer is at least 80nm.

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