We summarize the properties of 850nm wavelength AlGaAs/GaAs-based transceiver chips, monolithically integrating
vertical-cavity surface-emitting lasers (VCSELs) and metal-semiconductor-metal (MSM) or PIN-type
(p-doped-intrinsic-n-doped) photodiodes. Different chip designs enable half- and full-duplex bidirectional optical
interconnection at multiple Gbit/s data rate over a single butt-coupled glass or polymer-clad optical fiber with
core diameters ranging from 50 to 200 μm. The chips at both fiber ends are nominally identical and no external
optics is required, which leads to lower cost in addition to volume and weight reduction. The commercial availability
of such chips would directly enable applications in data communication and sensing networks in various
environments such as automotive, home, industrial, in-building, or medical.
We present the monolithic design, fabrication and properties of 850nm wavelength AlGaAs-GaAs-based transceiver
chips with a stacked layer structure of a VCSEL and a PIN photodetector. Bidirectional data transmission via
a single, two-side butt-coupled multimode fiber (MMF) is thus enabled. The approach aims at a miniaturization
of transceiver chips in order to ensure compatibility with standard MMFs with core diameters of 50 and 62.5μm
used predominantly in premises networks. These chips are supposed to be well suited for low-cost and compact
half- and full-duplex interconnection at Gbit/s data rates over distances of a few hundred meters.
We report the fabrication and properties of 850nm wavelength AlGaAs/GaAs-based transceiver chips, in which
vertical-cavity surface-emitting lasers (VCSELs) and photodiodes are monolithically integrated. Various types
of devices allow half- and full-duplex bidirectional optical interconnection at multiple Gbit/s data rates over a
single butt-coupled glass or polymer-clad silica optical fiber with core diameters of 100 or 200 μm. Whereas
metal-semiconductor-metal (MSM) photodiodes are employed for these large-area fibers, we also investigate
the integration of PIN-type photodiodes which appear more promising in combination with standard 62.5 or
50 μm core diameter graded-index multimode fibers. This interconnect solution based on two identical chips is
attractive owing to lower volume, weight, and cost. Applications will be found in home, in-building, industrial,
or automotive networks and potentially within computer clusters or central offices.