Novel Diamond Nanowire Field Emission Triodes and Their Application as Buffer Amplifiers and Vacuum Switches

This paper reports a novel diamond nanowire (DNW) field emission triode (FET) and its application research as buffer amplifiers and vacuum switches. A DNW cathode and gate-anode integrated structure was fabricated by microfabrication, followed by the assembly together forming the field emission (FE) triode whose FE performance and applications as buffer amplifiers and vacuum switches were tested in a vacuum measurement system. The emission current of DNW-FET was modulated by the gate voltage, achieving a current density as high as 31.27 mA/cm2, DNW-FET exhibits moderate amplification factor (2.98), high transconductance (464.2 <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\mu \mathrm{S})$</tex>, low anode resistance (865.8 <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\Omega)$</tex>. AC amplification test shows that DNW-FET has an AC gain of 3.86 dB, indicating its potential as buffer amplifiers. Vacuum switching test demonstrates fast switching response <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$(3\ \mu \mathrm{s})$</tex>, high voltage change rate (16.09 <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\mathrm{V}/\mu \mathrm{s})$</tex>, high stability in conducting state (0.69%) and low power loss (20.65 <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\mu \mathrm{W})$</tex>, suggesting its viability for vacuum switches.