Ultra low background InGaAs epi-layer on InP for PIN applications by production MBE

By optimizing the MBE growth condition for the InGaAs layer on InP substrate, ultra-low InGaAs background concentration has been achieved. Hall measurements at room temperature show background concentration level of less than 3e14 cm^-3, with mobility as high as 12,300 cm²/V·s. While, C-V measurements show background concentration has decreased to 1e14 cm^-3 level with PlN photodetector epi structure. Commercial InGaAs PIN devices at 2 V reverse bias operation with an average 3 dB bandwidth of 4.6 GHz have been successfully fabricated from these MBE materials. For a 75 μm diameter device, room temperature dark current of 0.5 nA, and 1550 nm photo responsivity of 0.95 A/W were measured.