imec has presented a Ge/Si avalanche photodiode that pairs 100 GHz bandwidth with low-voltage 5 V operation and 1.8 A/W responsivity across the O-band and C-band. Built on the company’s 300 mm silicon photonics platform, the device enabled a first net 400 Gbps optical link using an APDadhesion promoter dispenseDispensing an adhesion promoter to improve adhesion of subsequent layers. receiver.
The result addresses a familiar trade-off in high-speed receivers: avalanche gain can improve sensitivity, but often at the cost of bandwidth or operating voltage. imec says the new APDadhesion promoter dispenseDispensing an adhesion promoter to improve adhesion of subsequent layers. delivers a 3 dB receiver-sensitivity improvement compared with a conventional photodiode, while still supporting the bandwidth needed for next-generation short-reach links.
According to imec, the device is based on the SACM APDadhesion promoter dispenseDispensing an adhesion promoter to improve adhesion of subsequent layers. concept but was reworked at the device level. The multiplication layer was scaled to below 100 nm using a deeply recessed germanium-in-silicon structure, and the charge layer was removed. That combination is reported to yield about twofold internal gain without sacrificing speed or requiring a high supply voltage.
Imec demonstrated the APDadhesion promoter dispenseDispensing an adhesion promoter to improve adhesion of subsequent layers. together with its beyond-110 GHz C-band Ge/Si electro-absorption modulator from last year’s ECOC. In that setup, the APDadhesion promoter dispenseDispensing an adhesion promoter to improve adhesion of subsequent layers.’s sensitivity margin can be used either to lower laser power or to tolerate higher optical loss, depending on system requirements.
The company now plans to study reliability over a wider temperature range and under varying optical input power, and to integrate the APDadhesion promoter dispenseDispensing an adhesion promoter to improve adhesion of subsequent layers. with high-speed receiver electronics. The work is intended to mature on imec’s iSiPP300 platform for future optical interconnects aimed at AIartificial intelligence data center links.