Underfill with low viscosity and low linear expansion coefficient

Abstract

The invention discloses underfill with low viscosity and low linear expansion coefficient for flip-chip packaging, which is prepared with the following raw materials by weight percent: 0-28.6 percent of bisphenol-type epoxy resin, 0-28.6 percent of organosilicon modified epoxy resin, 0.57-15.4 percent of toughening agent, 16.3-84.2 percent of alicyclic epoxy resin, 0.57-15.4 percent of latent curing agent, 0.55-5.56 percent of accelerator, 0.55-5.56 percent of surfactant, 0.57-27 percent of coupling agent, 7.4-66.7 percent of inorganic filler and 0-7.9 percent of pigment. With the ratio of the components, the invention overcomes the defects of the existing underfill, and has the advantages of: (1) high stability in the storage period; (2) low viscosity and good fluidity, wherein the viscosity is 1000-2000 centipoises; (3) low linear expansion coefficient (20-40ppm per DEG C); (4) high curing speed, wherein the underfill can be cured for 130 degrees within 5 minutes; (5) high shear strength (15MPa) and the like.

Description

technical field [0001] The invention relates to an underfill for chip packaging, in particular to a small gap mainly used for high integration of semiconductor equipment, flip-chip semiconductor devices, which can be packaged in a short time, and meet the needs of packaging reliability and high fluidity. Enhanced low viscosity, low coefficient of linear expansion underfill. Background technique [0002] With the high integration and high density of IC chips and the miniaturization of IC components, the application of flip-chip mounting is becoming more and more extensive. In this mounting method, the IC chip and the printed wiring board are connected not by soldering wires, but by small and thin solder bumps. However, due to the difference in thermal expansion coefficients of chips, printed wiring boards, and solder, thermal stress is likely to occur during a thermal shock test. In particular, the local thermal stress of the solder bumps far away from the center of the chi...

AI Technical Summary

Problems solved by technology

[0009] In order to solve the technical problem that the comprehensive performance of low viscosity and low linear expansion coefficient of the existing filling glue is not ideal, the present invention provides a low viscosity, low linear expansion coefficient, high bonding ability, and high reliability for flip-chip mounting. Underfill