Experimental and Numerical Thermal Analysis for Advanced Flip Chip Thermo-Compression Bonding via CMOS Microsensor Arrays and Finite Element Modelling

thermo-compression bonding;finite element analysis;flip chip;CMOS;RTD;microsensor;thermal contact resistance;thermal;thermal gradient;numerical analysis;Gold bumps

Athia, Depayneadvisor:Mayer, Michael ; affiliation1:Faculty of Engineering ; Mayer, Michael ;

University of Waterloo

关键词: CMOS;    Gold bumps;    RTD;    thermal contact resistance;    Master Thesis;    numerical analysis;    thermal;    thermal gradient;    thermo-compression bonding;    finite element analysis;    flip chip;    microsensor;   

Others  :  https://uwspace.uwaterloo.ca/bitstream/10012/12523/3/Athia_Depayne.pdf

瑞士|英语

来源: UWSPACE Waterloo Institutional Repository

【 摘 要 】

Thermo-compression bonding (TCB) relies on uniform thermal distribution duringmicroelectronic packaging processes to ensure reliable interconnects are formed. Duringany TCB processes, the thermal application must uniformly distribute heat in order to producerobust, thoroughly bonded packages without being damaged due to thermo-mechanicaleffects. To better control and develop TCB processes, further insight through thermalanalysis is required. Due to the form factors and complexity involved in TCB, it is difficultto accurately extract viable information such as temperature variation, lateral and verticalgradients, or interfacial bonding temperatures.To extract real time in-situ temperature and force signals, a microsensor array wasused to observe any thermo-mechanical features recorded during emulated TCB processes.Algorithms were developed to post-process the signals and produce quantifiabledata. Finite element models were developed to verify the experimental thermal responsesand subsequently post-analyze the numerical results. Models formed through hybridizedcontact resistance layers as well as surface contact models are also discussed.Several features were identified and quantified: maximum heating rates, locationof maximum lateral thermal gradients, internal joint thermal distributions, knee-regionslope analysis and joint to joint thermal variation. The experimental responses in combinationwith numerical analyses show evidence that thermal applications during TCB isrobust. Low thermal variation was found with respect to joint to joint temperatures. Chipdesign was found to heavily influence cooling on the periphery edges of the bump array.The sensor chip temperatures were to found to be about ≈ 6 °C lower than the extractedbump temperatures, signifying the use of microsensor arrays could be developed as accuratetools for thermal process control during TCB.