TRAVELING-WAVE PHOTODETECTORS WITH 172-GHZ BANDWIDTH AND 76-GHZ BANDWIDTH-EFFICIENCY PRODUCT

Results of the first fabrication and measurement of travelling-wave ph otodetectors are reported. The devices have bandwidths as high as 172 GHz, the highest reported for a p-i-n photodetector, and bandwidth-eff iciency products as large as 76 GHz, the largest reported for any phot odetector without gain. Comparisons with vertically illuminated and wa veguide photodetectors fabricated on the same wafer establish the supe rior performance of travelling-wave photodetectors. Microwave loss on the travelling-wave photodetector structure is identified as a bandwid th limitation.