On the temporal behavior of dc and rf characteristics of InAs nanowire MISFET

In this paper InAs nanowire transistors were investigated. The vapor-solid growth mode using Au nanoparticles as a seed was used for the growth of the nanowires on InAs substrates. In order to fabricate top-gate transistors the nanowires were transferred to a Si/SiO₂ host substrate. The host substrate was pre-patterned with contacts by optical lithography and Ti/Au deposition. These contacts were used for field-assisted controlled deposition of the InAs nanowires followed by the patterning of the coplanar source and drain contacts. The deposition of the gate isolation dielectric is a crucial step within the fabrication process due to thermal budget limitations of about 250 °C. The authors have investigated the room temperature deposition of 30 nm SiN_x using electron-resonance source for chemical vapor deposition with N₂ and SiH₄ precursors which provides the highest transconductance. Drift and hysteresis were observed in the DC output characteristics. Two types of hysteresis, counter-clockwise (CCW) and clockwise (CW), were found, for both the output and transfer characteristics, if the sweep rates were fast and slow, respectively.