Gallium nitride nanowire field effect transistor for high temperature applications

Abstract

F.SF01.09.04 Gallium Nitride Nanowire Field Effect Transistor for High Temperature Applications Abstract Body: Wide bandgap (WBG) semiconductor-based electronics are becomingthe center of interest due to their ability to operate at high temperatures and highvoltages. Gallium Nitride (GaN), as one of the WBG semiconductors, is a strongcandidate that can meet expectations in high-temperature electronic applications suchas military systems, automotive and aerospace control units, gas and oil explorationdrilling systems. The superior physical properties of GaN nanowires such as high directbandgap, high breakdown voltage, and high thermal conductivity, as well as highsurface area to volume ratio, make it even more signiÒcant material for harshenvironments. In this work, we investigate the electrical transport properties of a backgated single GaN nanowire Òeld-e×ect transistor (GaNNW-FET) at elevatedtemperatures. In order to analyze transport properties (IDS-VDS and IDS-VGS),electrical measurements were performed at temperatures ranging from roomtemperature to as high as 350°C. The device performs very well until 250°C, whereas itshows some reduction in current values beyond 300°C. In fact, the drain currentincreases by 2.1, 13.6 and 19.7 times at the temperatures of 100°C and 200°C, 250°C,respectively, with respect to room temperature current at the same bias voltage of 1 V.The enhancement of current is likely due to the reduction of contact resistancebetween the nanowire and electrodes as well as an increase in thermally excited carrierconcentration. On the other hand, degradation of current is likely due to the increase inlattice scattering, lowering the carrier mobility, of the GaN nanowire. Moreover, theinÓuence of high temperature on important transport properties such astransconductance, carrier concentration and carrier mobility will be presented indetails. The device o×ers the following unique advantages: (i) stable operation at hightemperatures (at 350°C), (ii) exhibiting an on/o× current ratio of 5.5 x 102 and a hightransconductance value of 3.09 µS at 350°C indicating a good gating e×ect even at hightemperatures, and iii) o×ering solutions not only for high-power but also for low-powercircuit and photonic applications at high temperature ambients (> 300oC). In summary,GaNNW-FET proves to be an excellent device capable of operating at hightemperatures enabling the development of high-performance nanoelectronic/photonicdevices especially for harsh conditions.