Research On Fabrication Process Of High Power LED

Solid-state lighting is provided with the virtues of saving energy, environment protection, long lifetime and compact size, etc. It is gradually applied in various aspects of colored and white lighting. However, compared with the luminous flux of the general lighting products such as incandescent light bulb and fluorescent tube, high power LED, as a kind of light source, some gaps still exist. Therefore, to make the LED widely used in the lighting market, the key is to raise its luminous efficiency and luminous flux to the level of existing illumination source.Firstly, this article begins with the basic principles of high power LED, including the luminous principles, the structure of the devices and the effect of each layer. Then it gives the performance indicators of high power LED. Furthermore, it tells the related technology of the fabrication of high power LED s chips.Secondly, the principles of the current spreading to solve the current crowding problem are given. Then it designs two new structures of 1W high power LED by L-edit, both of which are 1mm×1mm. Based on the layout, it produces the high power LED. The testing results showed that the second version is better than the first version, and the new process is better than the normal process. After making the SEM test of the chips, test results show that it completes the basic structure of high power LED. Meanwhile the experimental results in line with expectations and the surface micro-topography of the chips are perfect. Furthermore, the aging test shows that the lumen maintenance of the chips can achieve stability after a period of time.Finally, in order to improve the luminous intensity of high power LED, backside metallization and the structure of photonic crystal are made. The conclusion of the back metallization can effectively improve the high power LED chip s luminous intensity. Photonic crystals can also greatly improve luminous intensity of high power LED.