Temperature dependence and persistent conductivity of GaAs MESFETs with superlattice buffers

The DC characteristics of GaAs MESFETs with superlattice buffers were studied at room and liquid-nitrogen temperatures. It was found that the superlattice buffers provide effective screening for the active layers at room temperature and in the dark. At 77 K, however, persistent conductivity induced by ambient light or high gate bias was observed. The origin of the conductivity is presumably due to the activation of deep centers associated with the superlattice.<
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