The entry barrier of the LED industry chain from upstream to downstream industries is gradually lowered. The upstream is the single wafer and its epitaxy, the midstream is the LED chip processing, and the downstream is the packaging test and application.

Among them, the upstream and midstream have high technology content and high capital investment density, making them the areas with the most intense international competition and the greatest operational risks.

In the LED industry chain, LED epitaxial wafers and chips account for about 70% of the industry's profits, LED packaging accounts for about 10-20%, and LED applications also account for about 10-20%.

　　 Single chip is the base for manufacturing LED, also called substrate, mostly using sapphire, silicon carbide, GaAs, GaP as materials.

The epitaxial wafer is to grow multiple layers of single crystal films with different thicknesses on a single crystal, such as AlGaAs, AlGaInP, GaInN, etc., to realize LEDs of different colors or wavelengths.

Common epitaxy methods include liquid phase epitaxy (LPE), vapor phase epitaxy (VPE), and metal organic chemical vapor deposition (MOCVD), among which VPE and LPE technologies are quite mature and can be used to grow general-brightness LEDs.

The MOCVD method must be used to grow high-brightness LEDs. At present, the major global MOVCD manufacturers are AIXTRON in Germany and VEECO in the United States.

The former occupies about 60%~70% of the international market share, and the latter occupies 30%~40%. Equipment produced by Japanese manufacturers is basically limited to sales in Japan.

　　Midstream is mainly chip design and processing. Midstream manufacturers carry out device structure and process design according to the performance requirements of LEDs, through epitaxial wafer diffusion, and then metal coating,

Then photolithography, heat treatment, metal electrodes are formed, and then the substrate is thinned and polished and then cut.

　　The downstream includes the packaging, testing and application of LED chips. LED packaging refers to connecting the outer lead to the electrode of the LED chip to form an LED device,

The package plays a role in protecting the LED chip and improving the efficiency of light extraction. LED packaging technology is developed from the packaging technology of semiconductor discrete devices.

At present, the packaging types of LED products mainly include Lamp type, plug-in type (ThroughHole), surface mount type (SMD), direct bonding type (DirectBonding) and so on.

Among them, SMD LEDs are smaller than other traditional LEDs, so SMD LEDs are mainly used for mobile phone screen backlights and mobile phone buttons, which are greatly affected by mobile phone demand.

 To install an LED display outdoors, what application and approval procedures should be followed?

In the new media era, LED displays are increasingly used in advertising media, especially outdoor advertising media. So what approval process does outdoor full-color LED display need to go through when installed outdoors? In order to put outdoor LED display advertising normally, Xinyasheng Optoelectronics will analyze the specific process of outdoor full-color LED display advertising in detail for you.

First of all, adjust measures to local conditions, according to your own advertising needs, do not blindly follow the trend. For example, if you put on the front screen of a small store, you only need a small LED single and double color screen or LED full-color screen, no formalities are required, and you can directly order the LED display and install and use it. If it is installed outdoors and used for outdoor media advertising, you need to go through relevant procedures before installing the LED display screen before it can be used normally.

LED display advertising is the same as outdoor advertising:

 >> First of all: To apply for outdoor advertising registration, the basic requirements for applying for outdoor advertising registration:

1. Obtain the business qualifications in accordance with the application items in accordance with the law, and have the ownership of the corresponding outdoor advertising media.

2. Comply with the requirements of the local people's government and the advertising management department's outdoor advertising setup plan.

>>Secondly: Provide the supporting documents required for the "Outdoor Advertising Registration Certificate":

1. A copy of the business license;

2. An advertising contract (original);

3. A copy of the advertising business license.

4. One copy of "Outdoor Advertising Registration Application Form".

5. A copy of the agreement for the use of the advertising release site (original).

According to laws and regulations, the approval of relevant government departments is required, and the approval documents issued by the relevant departments should be submitted.