There are some high-brightness LED chips on which the positions of the two electrodes of pn are close to each other, which improves the luminous efficiency and heat dissipation capability of the chip. There are some high-brightness LED chips on which the positions of the two electrodes of pn are close to each other, which improves the luminous efficiency and heat dissipation capability of the chip. Recently, the existing production is to remove the LED epitaxial wafer from the GaAs or GaN long crystal substrate and bond it to another metal substrate by using the newly improved laser lift-o and metal bonding technology. Or other materials with high reflectivity and high thermal conductivity help high-power LEDs improve light extraction efficiency and heat dissipation. Package design After years of development, vertical (φ3mm, φ5mm) and SMD lamps (surface mount LEDs) have evolved into a standard product model. However, with the development and needs of the chip, we have developed a package design that meets high power. In order to reduce manufacturing costs by using automated assembly technology, high-power SMD lamps have emerged. Moreover, driven by the rapid market of portable consumer products, the design of high-power LED package volume is smaller and thinner to provide a wider product design space. In order to maintain the brightness of the finished product after packaging, a new modified high-power SMD device with a cup-shaped reflecting surface helps to reflect all the light out of the package to increase the output. Covering the round shape of the LED, the material is changed to use Silone sealant instead of the epoxy resin (Epoxy), so that the package can maintain a certain durability. The main purpose of the package is to ensure the correct electrical and mechanical interconnection between the semiconductor chip and the underlying circuit, and to protect the chip from mechanical, thermal, humid and other external impacts. When selecting the packaging method, materials, and operating the machine, factors such as the shape of the LED epitaxial, electrical/mechanical characteristics, and the accuracy of the die attach must be considered. Due to the optical properties of LEDs, packaging must also be considered and ensured in optical properties. Whether it is a vertical LED or SMD package, a high-precision die bonder must be selected. The accuracy of the LED die placed in the package directly affects the luminous performance of the package. If the position of the crystal grains in the reflective cup is deviated, the light is not completely reflected, which affects the brightness of the finished product. However, if a solid crystal machine has an advanced pre-image identification system (PRSystem), it can be precisely welded to a predetermined position in the reflector cup despite the poor quality lead frame. Generally, low-power LED devices (such as the illumination of pointing devices and mobile phone keyboards) are mainly solid crystals with silver paste. However, since the silver paste itself cannot withstand high temperatures, while the brightness is increased, heat is generated, which affects the product. In order to obtain high-quality and high-power LEDs, a new die-hardening process has been developed. One of them is to use eutectic soldering technology to solder the die to a heat sink (soubmount) or heat sink. Then, the whole die is connected to the heat dissipating substrate and soldered to the package device, so that the heat dissipation capability of the device can be enhanced, and the hair is relatively increased. As for the substrate material, silicon (Silicon), copper (Copper) and ceramic (Ceramic) are commonly used heat-dissipating substrate materials. Infrared Optical,Zinc Selenide Lens,Optical Zinc Selenide Lens,Optical Imaging Lens Danyang Horse Optical Co., Ltd , https://www.dyhorseoptical.com
From the evolution of the chip, it is found that major LED manufacturers continue to improve on the upstream epitaxial technology, such as using different electrode designs to control the current density, using ITO thin film technology to make the current distribution through the LEDs evenly distributed, etc., so that the structure All produce as much as possible. Then use a variety of different methods to extract each photon emitted by the LED, such as the production of chips of different shapes; use the periphery of the chip to effectively control the light refraction to increase the LED yield, and develop a single chip surface size (> 2mm2) to increase the luminous area It also uses a rough surface to increase the penetration of light and so on.
Packaging process and solution