Mechanically flexible interconnects (MFIs) for large scale heterogeneous system integration

Advanced packaging;Heterogeneous system;Flexible interconnects;Rematable assembly;CMOS/MEMS integration;Spray-coating;Interposer

Zhang, Chaoqi ; Bakir, Muhannad S. Electrical and Computer Engineering Wang, Hua Degertekin, F. Levent Brand, Oliver Joshi, Yogendra ; Bakir, Muhannad S.

University:Georgia Institute of Technology

Department:Electrical and Computer Engineering

关键词: Advanced packaging;    Heterogeneous system;    Flexible interconnects;    Rematable assembly;    CMOS/MEMS integration;    Spray-coating;    Interposer;   

Others  :  https://smartech.gatech.edu/bitstream/1853/53637/1/ZHANG-DISSERTATION-2015.pdf

美国|英语

来源: SMARTech Repository

【 摘 要 】

In this research, wafer-level flexible input/output interconnection technologies,Mechanically Flexible Interconnects (MFIs), have been developed. First, Au-NiW MFIswith 65 µm vertical elastic range of motion are designed and fabricated. The goldpassivation layer is experimentally verified to not only lower the electrical resistancebut also significantly extend the life-time of the MFIs. In addition, a photoresistspray-coating based fabrication process is developed to scale the in-line pitch of MFIsfrom 150 µm to 50 µm. By adding a contact-tip, Au-NiW MFI could realize a rematable assembly on a substrate with uniform pads and a robust assembly on asubstrate with 45 µm surface variation. Last but not least, multi-pitch multi-heightMFIs (MPMH MFIs) are formed using double-lithography and double-reflow processes,which can realize an MFI array containing MFIs with various heights and variouspitches. Using these advanced MFIs, large scale heterogeneous systems which can providehigh performance system-level interconnections are demonstrated. For example,the demonstrated 3D interposer stacking enabled by MPMH MFIs is promising torealize a low profile and cavity-free robust stacking system. Moreover, bridged multiinterposersystem is developed to address the reticle and yield limitations of realizinga large scale system using current 2.5D integration technologies. The high-bandwidthinterconnection available within interposer can be extended by using a silicon chipto bridge adjacent interposers. MFIs assisted thermal isolation is also developed toalleviate thermal coupling in a high-performance 3D stacking system.