TY - JOUR
T1 - Passive alignment and mounting of LiNbO3 waveguide chips on Si substrates by low-temperature solid-state bonding of Au
AU - Takigawa, Ryo
AU - Higurashi, Eiji
AU - Suga, Tadatomo
AU - Kawanishi, Tetsuya
N1 - Funding Information:
Manuscript received July 2, 2010; revised September 18, 2010; accepted October 15, 2010. Date of publication February 16, 2011; date of current version June 8, 2011. This work was supported in part by the Industrial Technology Research Grant Program in 2006 from New Energy and Industrial Technology Development Organization (NEDO) of Japan and in part by the Global COE Program (Global Center of Excellence for Mechanical System Innovation), Ministry of Education, Culture, Sports, Science and Technology (MEXT), Japan.
PY - 2011/5
Y1 - 2011/5
N2 - In this study, passive alignment and mounting of lithium niobate (LiNbO3) chips, with a large mismatch in the coefficient of thermal expansion with most semiconductors, are demonstrated for hybrid-integrated optical devices. LiNbO3 chips were aligned passively using the visual index alignment method and were subsequently bonded on the Si substrates by low-temperature solid-state bonding with Au microbumps, which allow for electrical connections and heat dissipation. Au-Au bonding was carried out at 100 °C in ambient air after surface activation by argon RF plasma. The vertical bonding accuracy was determined by assessing the height variations of the Au microbumps due to the plastic deformation in the bonding process. The bonding accuracies in the horizontal and vertical directions were estimated to be within ±1 μm. Average excess loss due to misalignment between titanium-diffused single-mode LiNbO3 waveguides and V-groove-guided single-mode fibers was about 0.5-dBm per interface (wavelength: 1.55 μm).
AB - In this study, passive alignment and mounting of lithium niobate (LiNbO3) chips, with a large mismatch in the coefficient of thermal expansion with most semiconductors, are demonstrated for hybrid-integrated optical devices. LiNbO3 chips were aligned passively using the visual index alignment method and were subsequently bonded on the Si substrates by low-temperature solid-state bonding with Au microbumps, which allow for electrical connections and heat dissipation. Au-Au bonding was carried out at 100 °C in ambient air after surface activation by argon RF plasma. The vertical bonding accuracy was determined by assessing the height variations of the Au microbumps due to the plastic deformation in the bonding process. The bonding accuracies in the horizontal and vertical directions were estimated to be within ±1 μm. Average excess loss due to misalignment between titanium-diffused single-mode LiNbO3 waveguides and V-groove-guided single-mode fibers was about 0.5-dBm per interface (wavelength: 1.55 μm).
UR - http://www.scopus.com/inward/record.url?scp=79958293242&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=79958293242&partnerID=8YFLogxK
U2 - 10.1109/JSTQE.2010.2093871
DO - 10.1109/JSTQE.2010.2093871
M3 - Article
AN - SCOPUS:79958293242
SN - 1077-260X
VL - 17
SP - 652
EP - 658
JO - IEEE Journal on Selected Topics in Quantum Electronics
JF - IEEE Journal on Selected Topics in Quantum Electronics
IS - 3
M1 - 5713807
ER -