Hot flip-chip process heat - force modeling and simulation of multi - parameter
|School||Central South University|
|Course||Mechanical Design and Theory|
|Keywords||Electronic Packaging Thermosonic flip Finite Element Analysis Coupled thermo Multi-parameter simulation|
Microelectronics industry rich understanding of the technology and process parameters to select the experience accumulated by the industry in the long - term industrial production , and the development of various forms of bonding equipment . The principle is still the lack of system clarifies many important phenomena related to the core mechanism , and more likely to stay in the qualitative description , far can not meet the high-density packaging interconnect technology requirements . A variety of physical , chemical , mechanical effect , the various parameters of the bumps on the tiny keys together quite difficult to real - time test simulation is an effective means to solve the above problems , using the finite element software . This paper the experimental results of the use of hot flip-chip bonding process , as the initial conditions of the simulation , the establishment of a finite element model of the hot flip-chip process , multi - parameter of the the tiny key thermosonic flip process together bump simulation. The main innovation points are as follows: an ultrasonic process , the material is softened or not only affect the magnitude of the stress , while not significantly affect its distribution ; different friction conditions on the interface of the stress distribution and the size of both effects: the larger the friction coefficient , the greater the concentration of stress generated in the interface ; 2, the transient temperature characteristics of the bonded area will affect the quality of the bonding , different bonding process parameters, so that the characteristics of the transient temperature of the interface is significantly different . Bonded to the pressure and the ultrasonic amplitude of the temperature rise and bonding closely related to the temperature slope is increased with the increase of the bonding pressure and ultrasonic amplitude . Of the ultrasonic amplitude of 0.7μm, bonded to a pressure of 30 g , ultrasonic load 9 msec , the interface temperature rise of 74.5 degrees ; 3, using the gold bumps on the interface obtained by the simulation plastic strain The nephogram and process of Fig. analysis combined with experimental results, the bonding strength on the interface generates location ; 4 under the combined effects of the ultrasonic amplitude, and the frictional force generated at the interface stress concentration, stress value is amplified , wherein the positive stress increased by 2 times , and the shear stress an increase of 0.7 times . Powerful stress so that the material is plastically deformed , plastic flow , and provide good conditions for the interface bonding strength is generated ; the above simulation result, the bonding mechanism for research , improve the quality of the bonding , and has an important reference value .