DIRECT CORRELATION BETWEEN IMPACT IONIZATION AND THE KINK EFFECT IN INALAS INGAAS HEMTS/

We present new, unmistakable experimental evidence directly linking th e kink effect with impact ionization in the channel of InAlAs/InGaAs H EMT's on InP. Through the use of a sidegate structure, we confirm that the impact ionization coefficient obeys the classic exponential depen dence on the inverse electric field at the drain end of the gate, and that the onset of the kink strongly coincides with the onset of impact ionization in the devices we consider. These measurements illuminate the functional relationship between the kink and impact ionization, an d therefore will allow assessment of the numerous impact-ionization re lated kink mechanisms that have recently been suggested in the literat ure.