The Research of Macro-Quality about LED Substrate during Precision Machining Process

The macro-quality of LED substrate includes integrity, the degree of warp, dimension accuracy and so on. We get the factors which affect macro-quality of LED substrate by experiment. The factors include the methods of substrate slicing, pasting, grinding and polishing. It is proposed to use wire cutting and the method of pasting by vacuum in order to improve the flatness of substrate. To prevent the collapse of edge during polishing we use special planet cage with protection edge. The velocity of chemical reaction has been coordinated with the rate of mechanical removal by adopting special chemical mechanical polishing liquid. As a result we can control the macro-quality of substrates efficiently and realize the shape integrity of surface, the degree of warp is less than 5 micron and the thickness error is less than 3 micron.