Testing and Packaging of Wavelength Converters

1. Zhaoyang Hu, Milan Mašanović, Matt Sysak, John Barton, Vikrant Lal, and Daniel J. Blumenthal University of California Santa Barbara, CA 93106 Tel: (805) 893-5614; Email: huby@ece.ucsb.edu Testing and Packagingof Wavelength Converters

2. Summary of Work • Test work • Test work at UCSB • Test work at MIT Lincoln Labs • Packaging work • Thermal analysis • Die boding and wire bonding test

3. AOWC Device Testing Work Test work at MIT Lincoln Lab Probe station preparation for test work at MIT Lincoln Lab Including device mount, platform for DC probe holders, etc. 2.5Gb/s NRZ BER measurement and RIN measurement Regeneration experiment with AOWC DARPA review 04/17 04/22 Date 04/25 05/01 05/05 05/06 05/07 05/08 Preliminary measurements of BER, RIN measurement, etc. At UCSB. SFDR, Optical noise figure and switching speed measurement Experimental setup buildup and AOWC measurement by all-parameter analyzer Discussion with MIT Lincoln Lab for equipment list, test work at MIT Lincoln Lab

4. Measurement Setup RIN measurement BER measurement SFDR measurement

5. 10Gb/s Receiver Clock Recovery Cascaded AOWC Test ---------Loop Configuration and Experiment Pre-dispersion AOM Loop output Data input data EDFA Driving current for SGDBR laser Post-dispersion OBPF AOM PC OBPF Constant power here AOWC OBPF ’data Low saturation EDFA EDFA Transmission Fiber spool data OBPF data OBPF OBPF EDFA PC SOA

6. Low Saturation EDFA Buildup Pump LD Erbium-doped fibers Gain-flatten filter WDM WDM Isolator Output Input signal Fusion splice Gain-flattening low saturation EDFA

7. Packaging Scheme • Using laser-welding machine, cooperated with Teledyne AuSn solder (melting point 280oC) AOWC Fiber cap Angled fiber AlN submount with Ti/Pt/Au film Ferrule clip Angled fiber Fiber Kovar ferrule Low-temperature InSnPb solder (melting point 95oC) InSnPb solder (melting point 118oC) Butterfly package InSnPb solder (melting point 118oC) Kovar submount TE Cooler 74.5o angled fiber if SOA 7o tilted 15.5o 7o 23o 74.5o

8. Thermal Analysis device 1. Simulation tools: ANSYS 2. Without TE-cooler, the temperature of the device is 100oC with 0.5W heat flux under a uniform ambient temperature of 25oC. 3. A constant temperature of 25oC is assumed at the bottom surface of copper for 10s while the operation of the device when TE-cooler is used. 4. A constant power of 0.5W and 1W is fed as a heat flux generated from the device. 5. The initial condition assumes a uniform ambient temperature of 25oC. 6. The dimensions: device is 4.5mm  0.5mm  0.1mm; copper is 10mm4.5mm  5mm; AlN submount is 10mm 4.5mm 0.5mm; AuSn solder preform is 4.5mm  0.5mm  0.1mm. AuSn solder ambient AlN submount Copper heatsink package TE-cooler 2-D simulation results 1W heat flux 0.5W heat flux

9. Thermal Analysis 3-D simulation results 0.5W heat flux 1W heat flux SMX=35.553oC SMX=30.277oC SMN=25oC SMN=25oC

10. Die Thin solder film Solder AlN submount Die Bonding and Wire Bonding Test • Hard eutectic solder of Au/Sn (80wt%/20wt%), shows less creep, have higher yield • strengths and fluxless attachment. • Possible any hotspots due to solder voids lead to localized heating between die and • submount. It could be solved through attach a thin solder film at the bottom of the die. Fluxless AuSn solder procesiing Dummy sample for testing die and wire bonding

11. Chip-on-carrier With Probe Card Chip-on-carrier Probe card

12. Future Work • Packaging • Cascaded AOWC test • Analogue characteristic measurement