Abstract
An Al/CdSe/GaSe/C thin film transistor device was prepared by the physical vapor deposition technique at a vacuum pressure of 10−5mbar. The x-ray diffraction measurements demonstrated the polycrystalline nature of the surface of the device. The dc current-voltage characteristics recorded for the Al/CdSe/C and Al/CdSe/GaSe/C channels displayed a resonant tunneling diode features during the forward and reverse voltage biasing, respectively. In addition, the switching current ratio of the Al/CdSe/C increased from 18.6 to 9.62×103 as a result of the GaSe deposition on the CdSe surface. Moreover, the alternating electrical signal analyses in the frequency range of 1.0MHz to 1.8GHz, showed some remarkable properties of negative resistance and negative capacitance spectra of the Al/CdSe/GaSe/C thin film transistors. Two distinct resonance-antiresonance phenomena in the resistance spectra and one in the capacitance spectra were observed at 0.53, 1.04 and 1.40GHz for the Al/CdSe/C channel, respectively. The respective resonating peak positions of the resistance spectra shift to 0.38 and 0.95GHz when GaSe is interfaced with CdSe. These features of the thin film transistors are promising for use in high quality microwave filtering circuits and also for use as ultrafast switches.
•Al/CdSe/GaSe/C thin film transistor device was prepared and characterized.•The Al/CdSe/C and Al/CdSe/GaSe/C channels displayed a resonant tunneling diode features.•The switching current ratio of the Al/CdSe/GaSe/C is 9.62×103.•The device exhibited resonance-antiresonance phenomena at 0.53, 1.04 and 1.40GHz.