Nano-diamond Field Emission Research Articles

Effects of temperature and vacuum on field emission characteristics of nano-diamond

For exploring the electron emission’s mechanism of nano-diamond under different temperature and vacuum degree, determine its limit working parameters, the nano-diamond coating’s field emission cathode was experimentally studied. The results show that the temperature rise has an impact on the field emission of titanium-based nano-diamonds. When the temperature exceeds 120 °C, the titanium matrix will emit a large number of electrons to form a larger emission current and drown the field emission current. The degree of vacuum will decrease as the temperature increases. This achievement provides a certain foundation for the design and manufacture of nano-diamond field emission displays.

Hydrogen Treatment Technology of Ti-based Nano-Diamond Field Emission Cathode

Abstract The field emission cathode coating of nano-diamond on titanium substrate was prepared by electrophoretic deposition, the hydrogen plasma process was carried out after heat treatment, and then the microstructure, field emission properties and the luminescence performance of the samples were characterized. The results show that the adsorption of H + and the etching of H + collectively affect the morphology of diamond coating. Deficient hydrogen treatment can't reach the requirement and excessive hydrogen treatment can lead to serious etching for the diamond coating, resulting in worse field emission properties of the coating and luminescence effect. The appropriate hydrogen treatment is helpful to improve the field emission properties and luminescence effect. Finally, the field emission mechanism of nano-diamond coating on titanium substrate was discussed, and the reasons of luminescence effect difference were explained.

Performance of field emission cathodes prepared from diamond nanoparticles

Nano-diamond field emission cathodes were fabricated using a two-step technique. A mixture of nano-diamond and nano-Ti powders was coated onto a Ti substrate using a spin-coating process, followed by the application of an annealing treatment to form a TiC phase. The effects of the annealing temperature and the number of coating layers on the electron field emission properties of the as-fabricated field emission cathodes were investigated. The samples fabricated under different conditions were analyzed by Raman spectroscopy, X-ray diffraction, and scanning electron microscopy. The differences in terms of the electron field emission properties were explained by a TiC network model. A higher temperature is necessary to form a continuous TiC network when a thicker coating is used on the field emission cathode. In contrast, for the thinner coating, a relatively low temperature is sufficient to form such a TiC network. Only a continuous TiC network coating can facilitate the passage of electrons through the coating and lead to emission.

Influence of Vacuum on Nano-Diamond Cathode Field Emission Characteristics

The test of nano-diamond cathode field emission characteristics was conducted by changing the vacuum, the influence of vacuum change on nano-diamond field emission characteristics was also explored. It was found that under the condition of low vacuum, nano-diamond field emission turn-on field is relatively high, as the vacuum increases, turn-on field decreases gradually, and current density increases. When system vacuum reaches to above 10-4Pa level, turn-on field becomes stable, the stable value is 4.5 V/μm; and current density also becomes stable, the stable value is 117 μA/cm2; the luminescence effect of anode which is 200μm distant from the cathode in the vacuum chamber also becomes stable. Results show that 10-4Pa is system vacuum limit parameter of stable working of field emission display, the experiment provides a basis to the design and manufacture of nano-diamond field emission display.

Study on the Field Emission of Titanium-Based Nanodiamond Diode Structure by Electrophoretic Deposition

A cathode process of nanodiamond field emission display based on diode structure by electrophoretic deposition has been explored. In this process, a certain proportion of nanodiamond electrophoresis liquid has been developed, the nanodiamond field emission cathode has been deposited on the polished metal titanium substrate by electrophoresis. The surface appearance and microstructures of the coating has been observed by scanning electron microscopy and Raman spectroscopy and the field emission properties of the prepared cathode coating has been tested. The experimental results show, the diamond-coated surface which has been deposited on titanium substrate is thin and uniform. Compared with the cathode prepared by the spin coating process, it has more field emission current density and better field emission current uniformity and stability. With a simple, low cost and large-area production and other advantages, it can be widely used in flat panel displays.

Study on Nano-Diamond Cathode Field Emission and Characteristics of Luminescence by Electrophoresis

Cathode samples of titanium-based nanodiamond field emission were prepared by electrophoresis dispersed solutions in different formulas. Observe the surface and structure of the coating by using metaloscope, microscopy, scanning electron microscopy (SEM) and X-ray diffraction (XRD); Test the field emission characteristic after annealing; Analyze the relation between the samples’ light photos and the uniformity of coating; Discuss the mechanism of the improved field emission characteristic after annealing. Under the same conditions the surface uniformity of diamond coating prepared by isobutyl alcohol is best,it is the minimum threshold electric field emission, 5.5 V/μm, the current density can reach to 85μA/cm2 at the field of 15V/μm. Field emission characteristic and luminescence could be best after annealing.

Effect of ballast-resistor and field-screening on electron-emission from nanodiamond emitters fabricated on micropatterned silicon pillar arrays

This paper describes the influence of ballast-resistor and field-screening on the electron field-emission behavior of nanodiamond emitter arrays fabricated on micropatterned silicon pillars. Arrays of 50 × 50 silicon pillars capped with nanodiamond with different ballast resistances and pillar separations have been fabricated on different silicon substrates as cathode for field emission testing. The goal of this study is to evaluate the fabrication method and electron emission characteristics in this configuration for field emission applications. The electron field emission results have been compared to observe the effect of the ballast resistive behavior and array spacing of micropatterned silicon pillars on the nanodiamond field emission behaviors.

Single-mask multiple lateral nanodiamond field emission devices fabrication technique

We report an efficient microfabrication process technique developed to realize multiple lateral diamond field emitter structures on the same wafer using a single mask. Nanodiamond films with grain size of 5–10nm deposited by CH4∕H2∕N2 microwave plasma enhanced chemical vapor deposition were selectively micropatterned using reactive ion etching at an etch rate of 0.5μm∕min. Several nanodiamond lateral field emission diodes and triodes of different emitter geometries and electrode configurations have been batch fabricated on a silicon-on-insulator wafer. Interelectrode spacing down to 2μm was achieved in arrays of devices on a SiO2 dielectric layer. This fabrication process technique, with its single-mask utility, high manufacturability, combined with its reproducibility, is an efficient and cost-effective approach to realize various configurations of field emission structures in wafer process technology. These nanodiamond vacuum nanoelectronic lateral devices hold high-speed and high-frequency operation potential.