Rectification properties of n-type nanocrystalline diamond heterojunctions to p-type silicon carbide at high temperatures

Abstract

Highly rectifying heterojunctions of n-type nanocrystalline diamond (NCD) films to p-type 4H-SiC substrates are fabricated to develop p-n junction diodes operable at high temperatures. In reverse bias condition, a potential barrier for holes at the interface prevents the injection of reverse leakage current from the NCD into the SiC and achieves the high rectification ratios of the order of 107 at room temperature and 104 even at 570 K. The mechanism of the forward current injection is described with the upward shift of the defect energy levels in the NCD to the conduction band of the SiC by forward biasing. The forward current shows different behavior from typical SiC Schottky diodes at high temperatures.

Sluggish Electron Transfer of Oxygen-Terminated Moderately Boron-Doped Diamond Electrode Induced by Large Interfacial Capacitance between a Diamond and Silicon Interface

“…The depletion layer width ( W ) was calculated to be 1.4 and 0.6 nm for of 0.1%BDD and 1.0%BDD, respectively, based on the following values from the literature: q χ D = 0.5 eV, E g,D = 5.47 eV, and U redox 0 = 0.449 eV. − Notably, 0.1%BDD has a lower carrier concentration and a larger depletion width, which contribute to the large charge transfer resistance. The proposed band diagram (Figure a) rationally explains the different charge transfer resistances of O-terminated 0.1%BDD (>500 Ω) and 1.0%BDD (∼50 Ω) observed in their Nyquist plots (Figures c and d).…”

“…The depletion layer width ( W ) and the energy barrier height ( V bi ) are expressed as eqs , and when the Fermi level is incorporated into the valence band maximum ( E F = E V ): W = 2 ε S i ε D V bi false( N Si 2 + N D 2 false) q false( ε Si N Si + ε normalD N normalD false) N Si N D V bi = ( q χ D + E g , D ) − ( q Φ Si + E g , Si ) where q is the elementary charge, ε Si , ε D , N Si , N D , q Φ Si , q Φ D , E g,Si , and E g,D are dielectric constants, acceptor concentrations, electron affinities, band gaps of Si and diamond, respectively. The energy barrier height ( V bi ) is calculated to be 0.80 eV using q Φ D , E g,D , q Φ Si , and E g,Si from the literature. ,, The estimated depletion width ( W ) of 0.1%BDD/Si was 10.0 nm, which is much larger than those of 0.1...…”

“…The depletion layer width ( W ) and the energy barrier height ( V bi ) are expressed as eqs , and when the Fermi level is incorporated into the valence band maximum ( E F = E V ): where q is the elementary charge, ε Si , ε D , N Si , N D , q Φ Si , q Φ D , E g,Si , and E g,D are dielectric constants, acceptor concentrations, electron affinities, band gaps of Si and diamond, respectively. The energy barrier height ( V bi ) is calculated to be 0.80 eV using q Φ D , E g,D , q Φ Si , and E g,Si from the literature. ,, The estimated depletion width ( W ) of 0.1%BDD/Si was 10.0 nm, which is much larger than those of 0.1%BDD/metals (1.4–1.7 nm). The larger W could have contributed to the larger charge transfer resistance of 0.1%BDD/Si (∼1500 Ω) than that of 0.1%BDD/metals (∼500 Ω).…”

Formation of nanocrystalline diamond cones by reactive ion etching in microwave plasma for enhancing field emission

“…3(c)], while the tip diameter is smaller due presumably to evaporation of Au during etching. Because Au has a large work function (∼5.4 eV) compared to 4.5 eV typical of an NCD film, 9,[25][26][27] process (IV) was done for removal of Au. In Figs.…”

Computationally assessing diamond as an ultrafast pulse shaper for high-power ultrawideband radar

“…Technologically, a canonical vertical p-i-n diamond DAS and DSRD n + layers can be obtained through fabricating a so-called merged diode (Kubovic et al, 2007), depositing bandgapmatched n-type AlGaN alloy or high-conductivity n-type Frontiers in Carbon frontiersin.org nanocrystalline diamond (NCD) (Nikhar et al, 2020). The last NCD-based strategy was successfully implemented to fabricate high quality rectifying p-n junctions where n-type NCD was deposited on p-type single crystal diamond (Kohn et al, 2006), SiC (Goto et al, 2014) and even Si (Teii and Ikeda, 2013). Because the n + NCD layer only serves as a charge collector, it must have low resistance through high carrier concentration and not necessarily through retaining the excellent transport properties of single crystal diamond.…”