Manufacturing method for flip chip gold bumps

Abstract

The invention belongs to the field of semiconductor package and discloses a manufacturing method for flip chip gold bumps. The method includes the following steps: by utilization of screen printing method, scaling powder with high viscosity is printed on an electrode under bump metal (UBM) plating layer; by utilization of a ball placing device, a matched template is chosen, gold balls are placed on a weld plating layer and the situation that the gold balls are adhered to the chip electrode UBM plating layer is ensured; and by utilization of lasers, the gold balls are re-melted, appropriate irradiation time and power are chosen, and the gold bumps are obtained and meet the shape requirement and requirements of electricity and mechanical performance. By utilization of laser braze, the manufacturing method for the flip chip gold bumps has the unique advantages of being capable of heating locally and quickly, cooling quickly and the like. The laser input power and the laser irradiation time are controlled, the gold bumps with optimal bump shapes, the mechanical performance and the electricity performance are obtained.

Description

technical field [0001] The invention relates to the field of semiconductor packaging, in particular to a method for manufacturing flip-chip gold bumps. Background technique [0002] In recent years, the two industries of flat panel displays and portable electronic products have developed rapidly. Electronic products such as mobile phones, electronic dictionaries, and digital cameras have become indispensable products in the daily life of modern people due to their small size, multi-functions, and ease of use. Large flat-panel displays have the advantages of lightness, thinness, no radiation and high resolution, and are gradually replacing traditional TVs and monitors. Whether it is a small mobile phone display or a large LCD monitor, driver chips are required. The LCD driver is characterized by a small chip area but a large number of I / O terminals. Obviously, the traditional IC packaging technology cannot meet the requirements of portable electronic products for short, thi...

AI Technical Summary

Problems solved by technology

In addition, for relatively brittle materials such as GaAs materials, the adhesion of the pads is small, and it is difficult to obtain good stud bumps

Moreover, the method of making nail-head Au bumps cannot meet the needs of mass production of multiple terminals, and it is difficult to ensure the uniformity of the shape of the bumps and the consistency of electrical contact performance.

Images