TEM and HREM of diamond crystals grown on Si tips: structure and results of ion-beam-treatment

Ultrananocrystalline Diamond-Decorated Silicon Nanowire Field Emitters

“…The UNCD coating is exceptionally uniform throughout the wire length, as compared to published reports. 24,25,32 The magnified image of a single nanowire also shows a uniformly UNCDcoated bulbous tip (shown in Figure 2d). …”

“…52 This leads to the formation of a Si−C interfacial layer that also acts as a nucleation site for UNCD growth. 31,32,48 Field emission measurements were carried out at room temperature after conditioning the films at around 10 μA at their respective field for about 2 h. The measured current density as a function of the macroscopic electric field is shown in Figure 10a,c, indicating that bare SiNWs can be turned on at E 0 = 4.3 ± 0.1 V/μm, while the UNCD/SiNW heterostructures exhibit a low threshold field of E 0 = 3.7 ± 0.1 V/μm. Emission current density of bare SiNWs goes as high as ∼0.1 mA/cm 2 at 25 V/μm, whereas the current density for UNCD/SiNW is one order of magnitude higher, reaching ∼2 mA/cm 2 at 25 V/μm and with no saturation yet observed at this field.…”

“…Numerous approaches have been developed to enhance the electron field emission properties of diamond films, including the modification of grain shape, reduction of grain size, increasing the conductivity by doping with boron and nitrogen species, and fabricating diamond tips through the utilization of high aspect ratio templates . Aligned silicon tip arrays, which have been used as templates for synthesizing diamond tips, were prepared by employing the conventional chemical vapor deposition, electron beam lithography, and chemical etching techniques, along with the microelectronic processes. ,− However, these approaches require a sophisticated apparatus and complex processing steps, which are tedious and expensive. On the other hand, building upon the valuable reported information related to diamond and SiNWs and the expertise of our group in the growth of ultrananocrystalline diamond (UNCD) using paraffin wax, we hereby present UNCD/SiNW nanostructures as upgraded electron field emitters.…”

Characterization and reactivity of charcoal from high temperature pyrolysis (800–1600 °C)

“…The additional structures, detected by the TEM analysis of spruce and oak chars, were related to the presence of inorganic matter such as Al 2 O 3 and Si [59,60]. In addition, TEM analysis showed that all char samples contained a small amount of SiC particles from the reactor's retort which could form the sp 3 diamond-like carbon in high-temperature pyrolysis [61,62].…”

Electrophoresis of Nanodiamond on the Growth of Ultrananocrystalline Diamond Films on Silicon Nanowires and the Enhancement of the Electron Field Emission Properties

“…The EFE properties of nanostructured materials, such as carbon nanotubes (CNTs), Si nanowires, nanostructured diamond films, and so on have caught great attention from researchers. − Among them, silicon (Si)-based nanoemitters such as silicon nanowires (SiNWs) are advantageous over other nanowire templates because of their compatibility with Si materials and have greater potential for integration with Si devices to form active electron field emitters. , Over the past years, researchers have reported successful synthesis of diamond tip using aligned silicon tip arrays as templates, which were prepared by the conventional chemical vapor deposition, thermal evaporation/decomposition, and laser ablation techniques, resulting in good electron field emission (EFE). − However, most of these techniques require sophisticated equipments and complicated processing steps, which are time-consuming and expensive. Several methods have been proposed to enhance the EFE properties of diamond films − and diamond-coated SiNW emitters. , However, conformal coating of diamond films on SiNWs is extremely difficult.…”