Title :
Low-temperature bonding of laser diode chips using atmospheric-pressure plasma activation of flat topped Au stud bumps with smooth surfaces
Author :
Yamamoto, Manabu ; Sato, Takao ; Higurashi, Eiji ; Suga, Takashi ; Sawada, Renshi
Author_Institution :
Sch. of Eng., Univ. of Tokyo, Tokyo, Japan
Abstract :
Surface activation by atmospheric-pressure plasma has been used for low-temperature bonding of laser diode (LD) chips. Coined Au stud bumps with smooth surfaces (Ra: 1.3 nm) and Au thin film electrodes (Ra: 2.1 nm) of LD chips were activated by Ar+O2 or Ar+H2 atmospheric-pressure plasma for 30 s and bonded in ambient air at low-temperature (25-150°C). Bonding strength was high enough to exceed the strength requirement of MIL-STD-883F, method 2019 (×2). The measured results of light-current-voltage (L-I-V) characteristics of the LD chips indicated no degradation after bonding.
Keywords :
bonding processes; gold; semiconductor lasers; Au; MIL-STD-883F; atmospheric-pressure plasma activation; bonding strength; laser diode chips; light-current-voltage characteristics; low-temperature bonding; smooth surfaces; stud bumps; surface activation; temperature 25 C to 150 C; thin film electrodes; time 30 s;
Conference_Titel :
CPMT Symposium Japan, 2012 2nd IEEE
Conference_Location :
Kyoto
Print_ISBN :
978-1-4673-2654-4
DOI :
10.1109/ICSJ.2012.6523387
