title: Junction field-effect-transistor-based germanium photodetector on silicon-on-insulator.
abstract: We propose and demonstrate a novel Ge photodetector on silicon-on-insulator based on a junction field effect transistor structure, where the field-effect transistor gate is replaced by a Ge island with no contact on it. Light incident on the Ge switches on the device by altering the conductance of the Si channel through secondary photoconductivity. The device's sensitivity is also enhanced by a vast reduction in parasitic capacitance. In cw measurements, proof-of-concept detectors exhibit up to a 33% change in Si channel conductance by absorbing only 200 nW of power at 1.55 microm. In addition, pulsed response tests have shown that rise times as low as 40 ps can be achieved.
authors.affiliation: Department of Electrical Engineering, University of California Los Angeles, 2330 Hospital Way, Los Angeles, California 90095, USA. subal@ee.ucla.edu
authors.forename: Subal
authors.initials: S
authors.lastname: Sahni
authors.forename: Xi
authors.initials: X
authors.lastname: Luo
authors.forename: Jian
authors.initials: J
authors.lastname: Liu
authors.forename: Ya-hong
authors.initials: YH
authors.lastname: Xie
authors.forename: Eli
authors.initials: E
authors.lastname: Yablonovitch