Technology for monolithic integration of GaInAs MSM photodetectors and AlGaAs/GaAs/AlGaAs-HEMT electronics

A process suitable for the monolithic integration of 1.3 μm MSM photodiodes and HEMT electronics is presented A new MBE growth concept has been implemented to improve the performance of GaInAs photodetectors grown on GaAs. Photodetectors fabricated on linear and step graded buffer layers as well as those grown on InP substrates have been compared. The measured responsivities at the wavelength of 1.3 μm were 0.34 A/W and 0.33 A/W for detectors on linear graded buffers and on InP, respectively. A -3 dB bandwidth of more than 8 GHz was obtained from high frequency measurements, The spectral response of the photodetectors show nearly the same responsivity for a wavelength of 1.3 μm as for 1.55 μm. Taking into account the high yield and reliability of our HEMT process the presented integration concept together with the new detector structure is suitable for large scale production of high performance long wavelength photoreceivers