Abstract
In this work, we demonstrate suspended two- and four-terminal field emission devices for high-temperature operation. The planar structures were fabricated with tungsten on a 200-nm silicon nitride membrane. The insulator in the vicinity of the terminals was removed to minimize undesirable Frenkel–Poole emission and increase the resistance of leakage current pathways. The effects of temperatures up to 450 °C on Fowler–Nordheim emission characteristics and parasitic leakage resistance were studied. Turn-on voltages with magnitudes under 15 V that further decreased as a function of increasing temperature for the two-terminal device were reported. Gating at temperatures of 150 °C and 300 °C was shown for the four-terminal device, and corresponding transconductance and cutoff frequency values were computed.
Highlights
V ACUUM field emission devices have been investigated for decades [1], [2] for various applications, including as sources in electron beam lithography [3], flat panel displays [4], microwave power amplifiers [5], and space propulsion systems [6]
The combination of the large electric field required for field emission with a high-temperature environment in an insulator can be detrimental to device operation as it leads to undesirable Frenkel–Poole current leakage [19], [20]
The membrane and the substrate were placed on top of a vacuum-safe heater (HeatWave Labs) with a thermocouple attached to the surface of the ceramic substrate inside of a stainless-steel vacuum system
Summary
V ACUUM field emission devices have been investigated for decades [1], [2] for various applications, including as sources in electron beam lithography [3], flat panel displays [4], microwave power amplifiers [5], and space propulsion systems [6]. On the other hand, do not rely on chemical doping for their device operation They are relatively insensitive to temperature changes until the onset of thermionic emission. The combination of the large electric field required for field emission with a high-temperature environment in an insulator can be detrimental to device operation as it leads to undesirable Frenkel–Poole current leakage [19], [20]. This is the field-assisted thermal ionization effect by which an insulator becomes electrically conductive before reaching dielectric breakdown [21], [22]. A refractory metal, as our electrode material due to its low work function (approximately 4.5 eV [24]) as well as its high-temperature tolerance
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
