The future of chip dicing

Cutting the chip with a diamond cutter will make the back side of the chip bear tensile stress (Tension Stress). Therefore, when the thickness becomes thinner, it will cause more serious back side chipping or cracking, and the Flip Chip packaging method is more prominent The quality problem of chip back collapse. Although reducing the cutting speed or adopting a step cutting method can improve the quality problem of chip back collapse, both of them need to pay the price of reducing production capacity. Japan DISCO company developed the so-called DBG (Dicing Before Grinding) process to solve this problem, but in addition to Dicing (cutting) and Grinding (back grinding), this DBG process also includes complicated Tape (tape) and De-tape (Remove the tape) procedure, so this idea has not been widely accepted by the industry. If the tool does not apply force to the chip during cutting, it will undoubtedly avoid the occurrence of chip back collapse. Therefore, non-contact cutting methods, such as laser or etching (Etch), are particularly noticed and expected by the industry. However, the above two alternative (Alternative) processes also have their own problems that need to be overcome, so there is currently no mass-produced related chip dicing machine. In addition to the problem of chip back collapse, in fact, the emergence of Low-k materials is the real reason for the current laser cutting machine to attract everyone's attention. Many Low-k materials are not suitable for cutting with diamond cutters due to their Porous or Polymer characteristics. However, if traditional lasers are used, they will also produce poor cutting quality due to high heat. The most ideal situation is to hope that all the energy of the laser can be used to remove Low-k materials without residual heat. In other words, the laser only needs to be responsible for removing Low-k materials, and the chip itself is still made of traditional diamonds. Cutting with a tool, unless the thickness of the chip is too thin to withstand the impact of the diamond tool or the laser light can easily cut it through, this kind of hybrid (composite) method should be a more reasonable approach. Although the Low-k laser cutting machine is favored by many people, it is only the more promising one among many candidate equipment at best. Before it officially becomes the main flow production equipment, it still has many problems to overcome, such as: when cutting In fact, we can judge from the fact that there is no low-k laser cutting machine that has been successfully verified by the semiconductor industry in Taiwan. , We can clearly understand that this battle is not over yet, and if domestic industry, academia, and research have a good idea, it is not completely without the chance to win the top spot in this new competition. (The above laser pipe cutting machine has been edited and organized on the Internet. Please indicate the source for reprinting!)