In this work,we investigate the influence of defect concentration of the diamond substrates on the performance of hydrogen-terminated diamond field-effect transistors by Raman spectra,pulsed I–V characteristics analy...In this work,we investigate the influence of defect concentration of the diamond substrates on the performance of hydrogen-terminated diamond field-effect transistors by Raman spectra,pulsed I–V characteristics analysis,and radio frequency performances measurements.It is found that a sample with higher defect concentration shows larger drain-lag effect and lower large-signal output power density.Defects in the diamond act as traps in the carrier transport and have a considerable influence on the large-signal output power density of diamond field-effect transistors.This work should be helpful for further performance improvement of the microwave power diamond devices.展开更多
2D material of graphene has inspired huge interest in fabricating of solid state gas sensors.In this work,epitaxial graphene,quasi-free-standing graphene,and CVD epitaxial graphene samples on SiC substrates are used t...2D material of graphene has inspired huge interest in fabricating of solid state gas sensors.In this work,epitaxial graphene,quasi-free-standing graphene,and CVD epitaxial graphene samples on SiC substrates are used to fabricate gas sensors.Defects are introduced into graphene using SF6 plasma treatment to improve the performance of the gas sensors.The epitaxial graphene shows high sensitivity to NO2 with response of 105.1%to 4 ppm NO2 and detection limit of 1 ppb.The higher sensitivity of epitaxial graphene compared to quasi-free-standing graphene,and CVD epitaxial graphene was found to be related to the different doping types of the samples.展开更多
基金This work was supported by the National Natural Science Foundation of China(Grant No.51702296)Excellent Youth Foundation of Hebei Scientific Committee(Grant No.F2019516002).
文摘In this work,we investigate the influence of defect concentration of the diamond substrates on the performance of hydrogen-terminated diamond field-effect transistors by Raman spectra,pulsed I–V characteristics analysis,and radio frequency performances measurements.It is found that a sample with higher defect concentration shows larger drain-lag effect and lower large-signal output power density.Defects in the diamond act as traps in the carrier transport and have a considerable influence on the large-signal output power density of diamond field-effect transistors.This work should be helpful for further performance improvement of the microwave power diamond devices.
基金supported by the National Natural Science Foundation of China (61674131 and 61306006)
文摘2D material of graphene has inspired huge interest in fabricating of solid state gas sensors.In this work,epitaxial graphene,quasi-free-standing graphene,and CVD epitaxial graphene samples on SiC substrates are used to fabricate gas sensors.Defects are introduced into graphene using SF6 plasma treatment to improve the performance of the gas sensors.The epitaxial graphene shows high sensitivity to NO2 with response of 105.1%to 4 ppm NO2 and detection limit of 1 ppb.The higher sensitivity of epitaxial graphene compared to quasi-free-standing graphene,and CVD epitaxial graphene was found to be related to the different doping types of the samples.