Title :
Ultra-fast and broadband photodetectors on low-temperature grown molecular-beam epitaxial GaAs
Author_Institution :
Inst. of Thin Film & Ion Technol., Res. Centre Julich, Germany
Abstract :
The material and device properties of low-temperature grown (LT) MBE GaAs photodetectors (PDs) are analysed regarding the optimization of their performance as a terahertz heterodyne photomixer. It is demonstrated that 550 GHz bandwidth can be achieved on LT GaAs PDs with interdigitated finger electrodes. The time-resolved pulse response shows 0.4 and 0.6 ps rise and fall times, respectively. Resulting bandwidth is in agreement with calculated using carrier lifetime of 0.2 ps, evaluated from reflectivity measurements, and capacitance of 0.014 fF//spl mu/m/sup 2/, obtained from microwave measurements. The device is RC limited and further improvement of the bandwidth needs to optimize the device area and the finger electrode geometry.
Keywords :
"Photodetectors","Bandwidth","Gallium arsenide","Fingers","Electrodes","Capacitance measurement","Microwave measurements","Performance analysis","Charge carrier lifetime","Reflectivity"
Conference_Titel :
High Performance Electron Devices for Microwave and Optoelectronic Applications, 1997. EDMO. 1997 Workshop on
Print_ISBN :
0-7803-4135-X
DOI :
10.1109/EDMO.1997.668586
