High power uni-traveling-carrier photodiodes

Photoresponse characteristics of InP-InGaAs UTC-PDs and their potential as high power devices are discussed. A fabricated UTC-PD with an InGaAs absorption-layer thickness W/sub A/ of 220 nm and a collection-layer depletion thickness W/sub C/ of 300 nm yielded high pulse-photocurrent up to 184 mA with an associated FWHM of 4.8 ps for a junction area of 40 /spl mu/m/sup 2/. A comparison of the optical RF response between UTC-PDs and conventional pin PDs has shown higher output capability of the UTC-PD at low bias.