Heat-dissipating ceramics have been paid more and more attention due to the development of high-power LEDs. This is because ceramics have excellent properties such as insulation, heat resistance and stability, which not only can resist high pressure, no deformation, no oxidation and no yellowing, but also The absolute advantage of the coefficient of thermal expansion (CTE) associated with the LED chip .
The heat-dissipating ceramics can be classified into two processes: HTCC (High Temperature Co-fired Ceramics) and LTCC (Low Temperature Co-fired Ceramics). The LTCC ceramics are perforated and positioned on the soft-baked raw embryos, and then Co-fired under the process conditions of 850 ° C, although this technology is easy to shape, but the ceramics are low in density, resulting in low thermal conductivity, poor mechanical strength and insulation properties, the most important is the green embryo after sintering There will be problems with shrinkage, which will lead to breakthroughs in dimensional accuracy. Therefore, the more elaborate lines are mostly modified with HTCC ceramics. The ceramics are sintered at a high temperature of 1300~1600°C, which makes them have better mechanical properties than LTCC ceramics, and further drills the surface of the substrate without dimensional accuracy. .
However, due to the extremely superior mechanical strength characteristics of ceramics, it is difficult to process on the surface with conventional cutting tools, so it is usually processed with a diamond knife (Diamond Saw) or a laser (Laser). Cutting with a lower cost diamond knife will cut the mechanical force in this way, which will not only cause the tool loss to be replaced, but also cause unevenness or cracking of the cutting edge of the substrate, in addition to water. Cooling limits the application of many processes. The laser not only has the advantages of high precision, local processing, rapid cutting and easy control of cutting images, but also is not limited by the hardness, brittleness and melting point of the material. Therefore, the laser technology is introduced into the ceramic cutting hole.
Unlike conventional spontaneous emission sources, lasers are sources of light that are stimulated by radiation, and this theory was inferred by Einstein in 1917, and it was not produced by Theodore Malman in 1960. Light Amplification by Stimulated Emissions of Radiation (LASER), which is a radiation source that is enhanced by stimulation radiation.
The main structure of the laser can be divided into three parts, namely the excitation element, the active medium and the resonant cavity. The excitation element is energized by high-voltage electricity to generate the energy of the active medium, and the medium absorbs the specific wavelength energy from the ground state to the excited state. The stable excited state will be reduced back to the ground state, which will release photons to produce light of a specific wavelength, which will be reflected in the two-sided mirror in the cavity, when all the light meets 2L=nλ Under the condition, the phase of the incident and reflected waves can be made uniform, and each other can form a standing wave to excite more photons to generate standing waves and traveling waves, and finally the traveling wave of the gain passes through the semi-reflective lens to form laser light. After the laser penetrates the output of the half mirror, it will be heated and vaporized by focusing on the target through the lens, and the purpose of cutting and punching is performed. Therefore, laser drilling can be performed by increasing the laser power or selecting a laser with a wavelength that is more easily absorbed by the material, and performing the process within an effective focusing range, which can effectively increase the cutting depth and reduce the process time. The purpose of mass production.
As early as 1989, Da Yi Technology began to introduce laser trimming device (Laser Trimming), and continued to introduce laser scribing to cut ceramic plates. After years of experience, it began to be accumulated in 2005. Self-developed laser machine, in 2009, laser drilling machine was officially developed for the formation of heat-dissipating ceramic holes, and the process of heat-dissipating ceramics was successfully introduced. After years of hard work, Dayi Group has 150 laser machines with different functions, and with the ability of self-developed and manufactured, it can modify or adjust the machine for customers at any time, so that the production products have more applications. Achieve the goal of product customization.
Incremental Encoder,Linear Scale Encoder,Dual Concentric Rotary Encoder,Dc Servo Motor Encoder
Yuheng Optics Co., Ltd.(Changchun) , https://www.yhencoder.com