Figure 3
Characteristics of device B, the Al–N-implanted TFET with a channel length of 70 nm. All of the measurements were conducted at 1.5 K unless otherwise noted. (a) Linear-scale dIS/dVD map. (b) IS–VD at VG = 0.253 V (marked by a triangle in (a)). The inset depicts the variation in the current during microwave irradiation with VD (near the sharp peak at −0.03 V, marked by the triangle in the main graph) and microwave power at a constant frequency of 32.7 GHz. (c) Is at (VD, VG) = (0.055 V, 0.253 V) as a function of magnetic field B⊥ (applied perpendicular to the substrate) and microwave frequency with a constant power P of 0 dBm (at the output of the microwave power source), showing ESR. The ESR response was measured for every other (VD, VG) set in (a), with 5 mV intervals for each voltage. The similar ESR is evident in the enclosed area marked by the dotted line in (a). Inset shows microwave power dependence of the ESR linewidth. (d) Temperature dependence of the ESR peak observed at (VD, VG) = (0.06 V, 0.25 V) with B⊥ = 1.255 T and P = 3 dBm. Note that the as-measured curves are shown without any artificial base current offset; thus, the higher the temperature, the higher the base current. (e) Schematic band diagram for double-dot-like transport with a deep impurity and an acceptor-like shallow impurity.
