NTT reports fastest transistor-based logic ICs
NTT fabricated two ICs using a 0.1-micron gate-length InAlAs/InGaAs/InP HEMT process, which provided a current gain cut-off frequency ft of 175 GHz and a maximum oscillation frequency fmax of 350 GHz.
A 100 Gbit/s selector IC contained two data buffers, a clock buffer and a 2:1 selector core circuit, which was designed to directly drive the external 50-ohm load without the need for output buffers. In order to confirm the error-free operation of the 100 Gbit/s selector IC, it was necessary to build a second IC capable of demultiplexing the 100 Gbit/s signal to 50 Gbit/s. This allowed the output waveform to be recorded using a 50 GHz bandwidth digitizing sampling oscilloscope.
Error-free operation with a bit error rate of less than 10-10 was confirmed for both the 100 Gbit/s multiplexing function of the selector IC and the 100 Gbit/s demultiplexing function of the second IC. Power dissipation was 3.2 W and 4.7 W, respectively.
The results will be presented at IEDM in paper #4.7, "100-Gbit/s Logic IC Using 0.1-µm-gate-length InAlAs/InGaAs/InP HEMTs," by K Murata et al. of NTT Corp.
