Modulation-doped MBE GaAs/n-AlxGa1-xAs MESFETs

Modulation-doped GaAs/n-Al
0.3
Ga
0.7
As MESFETs have been fabricated. At 77 K, DC transconductance of 160 mS mm
^-1
was observed, which is the highest transconductance value ever reported in this type of structure. The intrinsic transconductance was calculated to be 350 mSmm
^-1
, and the corresponding average electron drift velocity is 1.8 × 10
⁷
cm s
^-1
, which demonstrates the real advantage of this type of device in high-speed applications.