Reliability issues of both AlGaAs/ln(0.2)Ga(O.8)As DCFETs and HEMTs were investigated and compared. By placing donors in the conducting channel, this doped-channel approach reduces the field intensity near the heterointerface resulting in a suppression of impact ionization process in the channel. Therefore, a more reliable device characteristics of DCFETs could be expected. The experimental results, through the biasing stress and temperature dependent evaluations, demonstrated a strong correlation between the impact ionization rate and device reliabilities.
