Planar metal–insulator–semiconductor type field emitter fabricated on an epitaxial Al/Al2O3/Si (111) structure

Abstract

A planar metal–insulator–semiconductor (MIS)-type field emitter using epitaxial γ-Al2O3 (111)/Si (111) structure was successively fabricated and field-emission phenomena were observed. Planar MIS-type field emitters using epitaxially grown Al2O3 were fabricated by molecular beam epitaxy (MBE) method and characteristics of these emitters were evaluated. It was confirmed that the Al2O3 possessed good crystalline quality and surface morphology. The breakdown field of the epitaxial Al2O3 layer was able to increase in situ annealing at the substrate temperature of 750 °C. From experimental measurements of diode current, conduction band offset (ΔEc) value between the epitaxial γ-Al2O3 and Si (111) substrate was calculated to be 2.5 eV. Fowler–Nordheim (F–N) tunneling was observed from the 8-nm-thick epitaxial Al2O3 film. Emission characteristics were obtained from the 10-nm-thick epitaxial Al2O3 insulator with a 20-nm-thick Al gate electrode. The maximum transfer ratio of emission current was confirmed to be 1%.

Electrical Characteristics of Epitaxial γ-Al2O3/Si for Quantum Tunneling Device

“…This insulator thickness region may be applicable to a quantum tunneling device, such as an RTD or metal-oxide-semiconductor (MOS)-type field emitter (FE). 9,10) The current densityvoltage (J-V) and current density-electric field (J-E) characteristics indicated, breakdown fields of 6 to 12 MV/ cm and a low leakage current, as shown in Fig. 3.…”

Characteristics of Cost-Effective Ultrathin HfTiO[sub x] Film as Sensitive Membrane in ISFET Fabricated by Anodization

“…13 The operation of the ISFET is very similar to that of the conventional metal oxide semiconductor field-effect transistor ͑MOSFET͒ with the remote gate ͑reference electrode Ag/AgCl͒ exposing a chemically sensitive insulator to an electrolyte, which causes the linear voltage shifts of the I D -V GS characteristics of the ISFET due to the ionic charge interaction at the insulator surface, which modulates the threshold voltage V th . [14][15][16][17][18][19][20][21] The I D -V GS characteristics of the ISFET are illustrated in Fig. 6a and b, in which the HfTiO x -gate ISFET H sensor has the linear sensitivity of ϳ58 mV/pH during the triode region in the concentration range between pH 2 and 10, which exhibits the quasi-Nernstian response.…”

Growth of epitaxial γ-Al2O3(1 1 1) films with smooth surfaces on chemically oxidized Si(1 1 1) substrates using an Al–N2O mixed source molecular beam epitaxy

“…Device applications, such as metal-oxide-semiconductor field effect transistors (MOSFET), resonance tunneling diodes and planer-type field emitters, etc., have been reported [7][8][9]. In the device fabrication, an Al-N 2 O mixed source molecular beam epitaxy (MBE) was used following an Al 2 O 3 pre-layer formation, which is called as 2-step growth method [10].…”