We present a pluggable radiation-tolerant 4-level Pulse-Amplitude-Modulation (PAM4) optical transmitter module called GBT20 (Giga-Bit Transmitter at 20 Gbps) for particle-physics experiments. GBT20 has an OSFP or firefly connector to input 16 bit data each at 1.28 Gbps. The GBT20 drives a VCSEL die with an LC lens or a VCSEL TOSA and interfaces an optical fiber with a standard LC connector. The minimum module, including the host connector, occupies 41 mm × 13 mm × 6 mm. At 20.48 Gbps, the minimum Transmitter Dispersion Eye Closure Quaternary (TDECQ) is around 0.7 dB. The power consumption is around 164 mW in the low-power mode. The SEE cross-section is below 7.5 × 10−14 cm2. No significant performance degrades after a TID of 5.4 kGy.

The Quad transimpedance and limiting amplifier (QTIA) is a 4-channel array optical receiver ASIC, developed using a 65 nm CMOS process. It is configurable between the bit rate of 2.56 Gbps and 10 Gbps per channel. QTIA offers careful matching to both GaAs and InGaAs photodiodes. At this R&D stage, each channel has a different biasing scheme to the photodiode for optimal coupling. A charge pump is implemented in one channel to provide a higher reverse bias voltage, which is especially important to mitigate radiation effects on the photodiodes. The circuit functions of QTIA successfully passed the lab tests with GaAs photodiodes.

We present the design and the test results of a quad-channel optical transceiver module (QTRx) possibly for future particle physics experiments. The transmitters of QTRx, each at 10 Gbps, are based on a Quad-channel VCSEL Diode array Driver (QLDD) and 1 × 4 VCSEL array. The receivers of QTRx, with data rates of 2.56 Gbps or 10 Gbps per channel, are based on a Quad-channel Trans-Impedance and limiting Amplifier (QTIA) and 1 × 4 photodiode array of GaAs or InGaAs. QTRx is 20 mm × 10 mm × 5 mm and couples to an MT fiber connector. Test results indicate that QTRx achieves the design goals with a power consumption of 124 mW per transmitter channel at 10 Gbps and 120 mW at 2.56 Gbps per receiver channel with an on-chip charge pump. The sensitivities of QTIA are −17 dBm at 2.56 Gbps and −8 dBm at 10 Gbps, respectively. Further improvements with a gold-finger interface and a more compact optical lens are being designed.

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The key issues of local-area-network (LAN) and metropolitan area network (MAN) applications are to improve cost, manufacturabilily and reliability of optoelectronic devices in high speed transmission. The authors have demonstrated low cost, high manufacturability and thermal stability mini-transmitLer for 10Gh/s Ethemet applications in this paper. A novel two lens semi-passive alignment structure of 10Gb/s 1310nm SC receptacle or pigtail type optical miniflat transmitter are designed and demonstrated to exhibit about 35% coupling el'ficiency with *5pm accuracy flip chip bonder general process of silicon optical bench (SiOB) and packaging flow. Moreover, a high resistivity silicon optical bench (IkWcm) and pressure-free bonding technique using the electroplated gold-!:in solder are also adopted to guarantee the transmitted performance in high speed operation. The eye diagram of 10Gb/s mini-flat transmitter developed in this study shown the excellent quality obtained passing IOGb/s Ethernet mask test with 30% margin. And the extinction ratio of transmitter is also proved to above 6dB at room temperature. The optical eye diagram of 1 OGbls transmitter developed in this study showing excellent eye quality passing 10Gb/s Ethernet mask test between O°C to 80'C. Finally, the reliability of transmitter is also performed in this paper.