Title :
Development of anhydride-based NCFs for Cu/Sn-Ag eutectic bonding and process optimization for fine pitch TSV chip stacking
Author :
Ji-won Shin ; Yong-Won Choi ; Young Soon Kim ; Un Byung Kang ; Young Kun Jee ; Ji Hwan Hwang ; Kyung-Wook Paik
Author_Institution :
Dept. of Mater. Sci. & Eng., Korea Adv. Inst. of Sci. & Technol. (KAIST), Daejeon, South Korea
fDate :
May 29 2012-June 1 2012
Abstract :
Methyl tetrahydrophthalic anhydride (MeTHPA), and Methyl hexahydrophthalic anhydride (MeHHPA) were added as curing agent for bisphenol A/phenoxy resin-based non-conductive film (NCF). Only NCF with MeTHPA showed thermal stability and void-less interface at 250°C, and addition of 0.5 wt% of latent curing accelerator showed minimum NCF cure at pre-bonding stage (120°C) and full NCF cure after main-bonding stage (250°C). The formulated NCF were applied to TSV chip on substrate bonding with Cu/Sn-Ag double bump to Cu pad joint structure. Film thickness and bonding pressure were optimized at 15 μm and 2.4 MPa to form state-of-art joint structure with optimal fillet shape. The joint structures were observed to be stable even after three reliability tests: high temperature storage test (HTST) of 200 hours, pressure cooker test (PCT) of 24 hours, and thermal cycle (T/C) of 200 cycles. Anhydride-based NCF showed stable joints due to flux-ability of anhydride; however, conventional dicyan diamide (DICY) based NCF showed broken joints after T/C due to lack of flux-ability.
Keywords :
circuit optimisation; copper alloys; eutectic alloys; fine-pitch technology; integrated circuit bonding; integrated circuit packaging; integrated circuit reliability; integrated circuit testing; resins; silver alloys; three-dimensional integrated circuits; tin alloys; Cu-Sn-Ag; HTST; MeHHPA; MeTHPA; PCT; anhydride-based NCF; bisphenol A; bonding pressure; curing agent; dicyan diamide; eutectic bonding; film thickness; fine pitch TSV chip stacking; high temperature storage test; joint structure; latent curing accelerator; methyl hexahydrophthalic anhydride; methyl tetrahydrophthalic anhydride; optimal fillet shape; pad joint structure; phenoxy resin-based nonconductive film; pressure 2.4 MPa; pressure cooker test; process optimization; reliability tests; size 15 mum; substrate bonding; temperature 120 degC; temperature 250 degC; thermal cycle; thermal stability; time 200 hour; time 24 hour; void-less interface; Bonding; Curing; Films; Joints; Reliability; Resins; Through-silicon vias;
Conference_Titel :
Electronic Components and Technology Conference (ECTC), 2012 IEEE 62nd
Conference_Location :
San Diego, CA
Print_ISBN :
978-1-4673-1966-9
Electronic_ISBN :
0569-5503
DOI :
10.1109/ECTC.2012.6248802