Gigabit transmitter array modules on silicon waferboard

Individually addressable, four-channel transmitter arrays operating at data rates of 1 Gb/s have been developed based on a hybrid optoelectronic integration approach called silicon waferboard. A key feature of silicon waferboard is the use of mechanical alignment features fabricated on the surface of a silicon chip that enable passive optical alignment of components such as lasers and optical fibers. The transmitter array, which operates at a wavelength of 1.3 μm, comprises a four-channel InGaAsP/InP laser array that is passively aligned to four single-mode fibers held in V-grooves. The transmitter array also includes a four-channel GaAs MESFET driver array chip that provides high-speed drive currents to the individual lasers. The laser array, driver array, and optical fibers are all spaced on 350-μm centers, which results in a four-channel transmitter array that fits within a width of only 2 mm. Transmitter array waferboards were housed in a specially developed package to permit high-frequency characterization. These transmitter array modules have demonstrated operation at data rates of 1 Gb/s per channel, with an interchannel crosstalk of -29 dB