Characteristics of pseudomorphic AlGaAs/InxGa1−xAs (0≤x≤0.25) doped-channel field-effect transistors

The pseudomorphic properties of doped-channel field-effect transistors have been thoroughly investigated based on AlGaAs/InxGa1−xAs (0≤x≤0.25) heterostructures with different In contents. Through various analytical schemes and device characterization, we observed that by introducing a 150 Å strained In0.15Ga0.85As channel we can enhance device performance; however, this strained channel is not stable after high-temperature heat treatment. By further increasing the In content up to x=0.25, the device performance started to degrade, which is associated with strain relaxation in this highly strained channel.