TY - GEN
T1 - Low-temperature bonding of LSI chips to polymer substrate using Au cone bump for flexible electronics
AU - Shuto, Takanori
AU - Watanabe, Naoya
AU - Ikeda, Akihiro
AU - Asano, Tanemasa
PY - 2011
Y1 - 2011
N2 - PEN (polyethylene naphthalate) is a promising polymer candidate of the substrate material for flexible electronics. But its glass transition temperature is as low as 150°C. We show that interconnection bonding of LSI chip to metallization on PEN film can be realized by using cone-shaped compliant bump. 20 um-pitch area array of cone-shaped Au bump was fabricated on a Si wafer by using a photolithography and electroplating. Counter electrode on the PEN film was composed of Au (top)/Ni/Al (bottom) layered structure, where Ni and Au layers were deposited by using electroless plating on patterned Al. We have investigated two designs of the counter electrode; one is simple metal pad and the other is an electrode in which cross-shaped slit was formed. The bonding between the cone-shaped bump and the simple pad electrode was found to be realized at 150°C. More than 10,000 connections with about 100 mΩ/bump were formed. When the cross-shaped slit was employed, room temperature bonding was achieved.
AB - PEN (polyethylene naphthalate) is a promising polymer candidate of the substrate material for flexible electronics. But its glass transition temperature is as low as 150°C. We show that interconnection bonding of LSI chip to metallization on PEN film can be realized by using cone-shaped compliant bump. 20 um-pitch area array of cone-shaped Au bump was fabricated on a Si wafer by using a photolithography and electroplating. Counter electrode on the PEN film was composed of Au (top)/Ni/Al (bottom) layered structure, where Ni and Au layers were deposited by using electroless plating on patterned Al. We have investigated two designs of the counter electrode; one is simple metal pad and the other is an electrode in which cross-shaped slit was formed. The bonding between the cone-shaped bump and the simple pad electrode was found to be realized at 150°C. More than 10,000 connections with about 100 mΩ/bump were formed. When the cross-shaped slit was employed, room temperature bonding was achieved.
UR - http://www.scopus.com/inward/record.url?scp=79960414244&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=79960414244&partnerID=8YFLogxK
U2 - 10.1109/ECTC.2011.5898752
DO - 10.1109/ECTC.2011.5898752
M3 - Conference contribution
AN - SCOPUS:79960414244
SN - 9781612844978
T3 - Proceedings - Electronic Components and Technology Conference
SP - 1770
EP - 1774
BT - 2011 IEEE 61st Electronic Components and Technology Conference, ECTC 2011
T2 - 2011 61st Electronic Components and Technology Conference, ECTC 2011
Y2 - 31 May 2011 through 3 June 2011
ER -