Fabrication and characteristics of lateral type GaN field-emission arrays using metalorganic chemical vapor deposition

Abstract

Growth of single crystalline GaN thin films on Si(111) substrates by high vacuum metalorganic chemical vapor deposition using a single molecular precursor Lateral type GaN field-emission diodes were fabricated by metalorganic chemical vapor deposition. In forming the pattern, two kinds of procedures were proposed: a selective etching method with electron cyclotron resonance-reactive ion etching ͑ECR-RIE͒ or a simple selective growth utilizing Si 3 N 4 film as the masking layer. The device fabricated using ECR-RIE exhibited electrical characteristics such as a turn-on voltage of 35 V for a 7 m gap and an emission current of ϳ580 nA/10 tips at an anode-to-cathode voltage of 100 V. The field emission characteristics of GaN tips were attributed to the tip structure, low electron affinity and short distance between the cathode and anode tips.

Molecular‐beam epitaxy fabrication and analysis of GaN nanorods on patterned silicon‐on‐insulator substrate

“…This is considered to be due to the edge effect, i.e., the electric field at the edge is stronger than that at other areas. In addition, these values are fairly high in comparison with the GaN-based field emitter results reported previously [6][7][8][9]16]. This structure can be more improved through the use of gate electrodes and fabricating smaller pattern size.…”

“…There are many research efforts to control the morphology and distribution of GaN-based field emitters such as patterning nanowires [6], fabricating lateral type emitters [7], decorating GaN grains on pyramid Si [8], and forming roughened film using H 2 plasma [9]. Emission currents estimated from results in these reports are about 10 -5 A/cm 2 , 10 -7 A/tip, 10 -8 A/tip, and 10 -11 A/cm 2 , respectively when applied electric field is 10 V/μm although it is difficult to make an accurate comparison between these field emission characteristics.…”

Ultralow Voltage GaN Vacuum Nanodiodes in Air

“…It is also informative to compare the performance of our GaN NVED devices to previously reported lateral n-type GaN vacuum electron diodes with similar geometry but with microscale rather than nanoscale dimensions. For a set of ten GaN vacuum diodes with a gap size of 7 μm, the reported collective turn-on voltage was 35 V and an average field-emission current of 58 nA per tip was achieved at 100 V at an operating pressure of 6 × 10 –7 Torr . Another study using vertical GaN pyramids as the emitter and an overhanging metal collector with a gap of 2.3 μm reported much higher turn-on voltages of ≥400 V and up to ∼150 nA/tip over a 10-tip array at a voltage of ∼570 V in vacuum .…”

Selective area growth of GaN nanorods on patterned W/SiO2/Si substrates by RF-MBE

“…Selective area growth (SAG) is one of the promising approaches for realizing the positioning and the arrangement of nanorods by utilizing the self-assembly pathway of crystal growth. The SAG of GaN has been mostly performed on substrates partly masked with insulator (SiO X or SiN X ) or W by using metalorganic vapor phase epitaxy (MOVPE) at extremely high growth temperatures of 1020-1100 1C [5][6][7][8][9][10]. The SAG of GaN using RF plasma-assisted molecular beam epitaxy (RF-MBE) is comparatively difficult, and only a few attempts have been made to achieve it.…”