Degradation-free modulation-doped field-effect transistors grown by organometallic chemical vapor deposition

Abstract
Using AlGaAs and GaAs grown by organometallic chemical vapor deposition (OMCVD), we have fabricated high‐transconductance modulation‐doped field‐effect transistors which do not exhibit the severe electrical degradation in the dark at 77 K that is ordinarily observed in such devices. Such degradation has been attributed to defects in the n+‐AlGaAs. Experiments on ohmic test devices using different OMCVD grown structures suggest that the improvement is due to a drastically reduced charge polarization in the n+‐AlGaAs layer.