Design and testing of a kinematic package supporting a 32/spl times/32 array of GaAs MQW modulators flip-chip bonded to a CMOS chip

• Published in: Journal of lightwave technology 2001-10, Vol.19 (10), p.1543-1559
• Main Authors: Ayliffe, M.H., Rolston, D.R., Chuah, A.E.L., Bernier, E., Michael, F.S.J., Kabal, D., Kirk, A.G., Plant, D.V.
• Format: Article
• Language: English
• Subjects: Bonding; Copper; Gallium arsenide; Kinematics; Packaging; Quantum well devices; Testing; Thermal loading; Thermal resistance; Thermoelectricity
• ISSN: 0733-8724; 1558-2213
• DOI: 10.1109/50.956142

Innovative approaches to the design and packaging of a high-performance module supporting a 32/spl times/32 array of GaAs multiple quantum-well (MQW) modulators flip-chip bonded to a 9/spl times/9 mm/sup 2/ complementary metal-oxide-semiconductor (CMOS) chip are described. The module integrates a minilens array, a copper heat spreader, a thermoelectric cooler (TEC) and an aluminum heatsink. The minilens array is aligned and packaged with the chip using a novel six degrees of freedom (DOFs) alignment technique. The kinematic design allows for the manual insertion of the module into a free-space optical system with no need for further adjustments. The chip is mounted directly on a flexible printed circuit board (PCB) using a chip-on-board approach, providing over 200 bond pad connections to the chip. Impedance-controlled lines were operated at 1.0 Gb/s with a crosstalk of 4.0% between nearest neighbor lines. The junction-to-TEC thermal resistance is 0.4/spl deg/C/W, allowing for the use of a single-stage TEC to regulate the chip at an operating temperature of 40/spl deg/C under a maximum thermal load of 13.1 W.