Research and Introduction of the Process Flow of Full-automatic Wafer Level Flip Chip Machine

Abstract

At present, there are many kinds of process technologies that can be used in the field of microelectronic packaging. Current mainstream technologies mainly include gate array package (BGA), flip chip technology (FC), chip scale package (CSP), system-in-package (SIP), and three-dimensional (3D) package. After years of development, flip chip technology has gradually developed into a mainstream technology in the field of electronic packaging. The biggest feature of the flip chip technology is that the interconnect line is short. Compared with other packaging methods, it has the characteristics of small area and high density, and the overall performance is better than other methods. In the context of flip chip technology, the development of its corresponding process equipment is particularly important for the improvement of the industry’s capacity. However, at present in the Chinese domestic market, there are very few institutions and companies that conduct research on domestic wafer-level flip-chip equipment, and they have not achieved mass production. The device we developed is a non-lead bonded wafer level flip-chip soldering machine for IC semiconductor material packages. It uses heating, pressing, and ultrasonic energy modules to form electrical connections between the chip electrodes and the substrate. Solid-state soldering and packaging processes for IC integrated circuits and other products. It is also compatible with flip-chip soldering of 4-inch wafer substrates or ceramic substrates, 6-inch, 8-inch, and 12-inch wafer substrates. It contains four major systems: mechanical systems, electronic control systems, image recognition systems, and software systems. The mechanical system consists of a wafer ring loading and unloading module, a wafer table module, a flip chip module, a die bonding head module, a dispensing module, an ultrasonic and heating and pressing module, a wafer substrate table module and a wafer substrate automatic loading and unloading module. Each module works in coordination with each other. After the chip goes through the flip chip and the die bonder module from the wafer table, it is connected with the substrate after the ball bonding by the glue and other fillers. And is supplemented by hot pressing or ultrasonic waves is supplemented to strengthen connection performance. After the equipment is debugged, the time of the cycle can be used to measure the time period of the whole flip-chip solid crystal up to 1.8s. The results were observed under microscope, the positioning accuracy of flip-chip welding can reach 10μm. The appearance of this device will not only realize the industrialization of the flip-chip interconnection technology of the IC semiconductor industry, but its successful development is of great significance to the domestic development and manufacturing of semiconductor packaging equipment.