Dehzangi et al. Nanoscale Research Letters 2012, 7:381 http://www.nanoscalereslett.com/content/7/1/381 Page 4 of 9 Figure 4 High magnifications TEM micrograph of etch depth profile to show the dimension of the nanowire. Results and discussion Results The electrical characterization of the transistor was characterized by semiconductor parameter analyzer (Lakeshore, Desert Cryogenics Agilent HP 4156 C, Agi- lent Technologies, Santa Clara, CA, USA). Figure 5 shows the transfer characteristic for DG and SGJLT. The pinch off effect can be seen due to positive lateral gate applying on the channel. The subthreshold swing (SS) and on/off ratio for double gate junctionless transistor (DGJLT) were 106 and 100 mV/decade, respectively, and for SGJLT were 105 and 167 mV/decade respectively. By increasing the positive gate voltage, the current dropped. This indicates that the device required positive gate volt- age to be turned off. The pinch off effect for both devices is recognizable which off state occurred in +1.5 and +2.5 V in DG and SG structures, respectively. The result for output characteristic shows that the drain current (ID) does not significantly increase with the negative increase of gate voltage (not shown), unlike the conventional p-type channel metal-oxide-semiconductor field-effect transistor (MOSFETs). Also, high and posi- tive threshold voltage (+1.2 V for SG and +0.8 V for DG) suggests that the device is in an on state. It indicates that the transistor was in the on state with zero gate voltage. The ID-VDS characteristics for SG and DG structures are shown in Figure 6 for positive gate voltage. Low current is due to the low doping concentration profile (1015 cm−3) for the channel, which is lower than reported current value of the high doping concentration profile (5 × 1019 cm−3) JLTs. The MOSFETs or JLTs with high doping concentration mostly suffered with the high scat- tering effect or threshold voltage variation. Low channel doping can improve field-effect mobility for improved transconductance and drive current and decrease the Figure 5 Transfer characterization graph for DG and SG JLT. scattering effect and thresholdvoltage variations [38]. It can also provide low current in an off state; however, low off current is achievable by increasing the gate work func- tion values. The electrical characteristics of the devices Figure 6 Output characteristic (a) and drain conductance (b) for DG and SGJLT.