Criteria for one-dimensional transport in split-gate field-effect transistors

The authors have fabricated AlGaAs-GaAs split-gate field-effect transistors with different lengths and widths in order to establish geometric design criteria for one-dimensional (1D) transport. The experiments show a more negative 1D threshold voltage for zero length split-gate devices (constrictions) than for finite length split-gate devices for the same given width. The experiments reveal the existence of a critical width between the gates below which a 1D regime cannot be supported in split-gate FETs longer than 0.5 mu m.<>