A field effect transistor comprising a source including a plurality of electrode projections with spaces in between. A drain includes a plurality of electrode projections each located in one of the spaces between the electrode projections of the source thereby forming a drain-source electrode connection area of alternating drain and source projections. A gate is spaced apart from the drain-source electrode area thereby forming a channel between the gate and the drain-source electrode connection area wherein the gate runs parallel to the channel. A plurality of nano-structures is located in the drain-source electrode area thereby to form an electrical connection between the electrode projections of the drain and source in the drain-source electrode connection area. The invention extends to a gas detector including a plurality of field effect transistors as described above located on a substrate.
