• Journal of the Korean Institute of Telematics and Electronics
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• v.23 no.5
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• pp.712-718
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• 1986

A shallow n+ layer of implanted phosphorus was used to lower the barrier height of PtSinSi schottky diodes. The reduction of barrier height of the forward turn-on voltages from 400mV to 180mV of the forward was followed by implantation of phosphorus at 35KeV with an ion dose of 8.0x10**12 atoms/cm\ulcornerand was activated at 925\ulcorner for 30min in dry O2. The test result showed that, as the ion-implanted dose increased, the forward turn-on voltage and reverse breakdown voltage were linearly decreased, but the saturation current and ideality factor(n) were linearly increased.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.7 no.3
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• pp.487-493
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• 1997

Ti/sic(4H) Schottky barrier diodes were fabricated. The donor concentration and the built-in potential obtained by capacitance-voltage(C-V) measurement was about $2.0{\times}10^{15}{\textrm}{cm}^{-3}$ and 0.65 V, respectively. The ideality factor of 1.07 was obtained from the slope of current-voltage(I-V) characteristics at low current density. The breakdown field under the reverse bias voltage was about $1.7{\times}10^3V/{\textrm}{cm}$ and was very high. The barrier height of Ti for SiC(4H) was 0.91 V, which was determined by the analysis of the saturation current-temperature and the C-V characteristics.

• Journal of the Korean Institute of Telematics and Electronics D
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• v.35D no.11
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• pp.70-77
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• 1998

Ni/SiC Schottky diodes have been fabricated using epitaxial 4H-SiC and 6H-SiC wafers. The epitaxial n-type layers were grown on $n^{+}$ substrates, with a doping density of 4.0$\times$10$^{16}$ c $m^{-3}$ and a thickness of 10${\mu}{\textrm}{m}$. Oxide-termination has been adopted in order to obtain high breakdown voltage and low leakage current. The fabricated Ni/4H-SiC and Ni/6H-SiC Schottky barrier diodes show excellent rectifying characteristics up to the measured temperature range of 55$0^{\circ}C$. In case of oxide-terminated Schottky barrier diodes, breakdown voltage of 973V(Ni/4H-SiC) and 920V(Ni/6H-SiC), and a very low leakage current of less than 1nA at -800V has been observed at room temperature. On non-terminated Schottky barrier diodes, breakdown voltages were 430V(Ni/4H-SiC) and 160v(Ni/6H-SiC). At room temperature, SBH(Schottky Barrier Height), ideality factor and specific on-resistance were 1.55eV, 1.3, 3.6$\times$10$^{-2}$ $\Omega$.$\textrm{cm}^2$ for Ni/4H-SiC Schottky barrier diodes, and 1.24eV, 1.2, 2.6$\times$10$^{-2}$$\Omega$.$\textrm{cm}^2$/ for Ni/SH-SiC Schottky barrier diodes, respectively. These results show that both Ni/4H-SiC and Ni/6H-SiC Schottky barrier diodes are very promising for high-temperature and high power applications.s..

• Korean Journal of Materials Research
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• v.8 no.4
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• pp.288-292
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• 1998

The p*-n ultra shallow junction diode with Co/Ti bilayer silicide was formed by ion implantation of $BF_{2}$ energy : 30KeV, dose : $5\times10^{15}cm^{-2}$] onto the n-well Si(100) region and RTA-silicidation of the evaporated Co($120\AA$)/Ti($40\AA$) double layer. The fabricated diode exhibited ideality factor of 1.06, specific contact resistance of $1.2\times10^{-6}\Omega\cdot\textrm{cm}^2$ and leakage current of $8.6\muA/\textrm{cm}^2$(-3V) under the reverse bias of 3V. The sheet resistance of silicided emitter region, the boron concentration at silicide/Si interface and the junction depth including silicide layer of ($500\AA$ were about $8\Omega\Box$, $6\times10^{19}cm^{-3}$, and $0.14\mu{m}$, respectively. In the fabrication of diode, the application of Co/Ti bilayer silicide brought improvement of ideality factor on the current-voltage characteristics as well as reduction of emitter sheet resistance and specific contact resistance, while it led to a little increase of leakage current.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2009.11a
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• pp.65-65
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• 2009

High temperature silicon carbide Schottky diode was fabricated with Au deposited on poly 3C-SiC thin film grown on p-type Si(100) using atmospheric pressure chemical vapor deposition. The charge transport mechanism of the diode was studied in the temperature range of 300 K to 550 K. The forward and reverse bias currents of the diode increase strongly with temperature and diode shows a non-ideal behavior due to the series resistance and the interface states associated with 3C-SiC. The charge transport mechanism is a temperature activated process, in which, the electrons passes over of the low barriers and in turn, diode has a large ideality factor. The charge transport mechanism of the diode was analyzed by a Gaussian distribution of the Schottky barrier heights due to the Schottky barrier inhomogeneities at the metal-semiconductor interface and the mean barrier height and zero-bias standard deviation values for the diode was found to be 1.82 eV and $s_0$=0.233 V, respectively. The interface state density of the diode was determined using conductance-frequency and it was of order of $9.18{\times}10^{10}eV^{-1}cm^{-2}$.

• Journal of information and communication convergence engineering
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• v.14 no.1
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• pp.35-39
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• 2016

In this paper, we develop a 94-GHz single balanced mixer with low conversion loss using planar Schottky diodes on a GaAs substrate. The GaAs Schottky diode has a nanoscale anode with a T-shaped disk that can yield high cutoff frequency characteristics. The fabricated Schottky diode with an anode diameter of 500 nm has a series resistance of 21 Ω, an ideality factor of 1.32, a junction capacitance of 8.03 fF, and a cutoff frequency of 944 GHz. Based on this technology, a 94-GHz single balanced mixer was constructed. The fabricated mixer shows an average conversion loss of -7.58 dB at an RF frequency of 92.5 GHz to 95 GHz and an IF frequency of 500 MHz with an LO power of 7 dBm. The RF-to-LO isolation characteristics were greater than -32 dB. These values are considered to be attributed to superior Schottky diode characteristics.

• JSTS:Journal of Semiconductor Technology and Science
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• v.3 no.1
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• pp.21-26
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• 2003

4H-SiC Schottky rectifiers were exposed to pure Ar discharges in a planar coil Inductively Coupled Plasma system, as a function of source power, of chuck power and process pressure. The reverse breakdown voltage ($V_B$) decreased as a result of plasma exposure due to the creation of surface defects associated with the ion bombardment. The magnitude of the decrease was a function of both ion flux and ion energy. The forward turn-on voltage ($V_F$), on-state resistance ($R_{ON}$) and diode ideality factor (n) all increased after plasma exposure. The changes in all of the rectifier parameters were minimized at low power, high pressure plasma conditions.

• Journal of the Korean Institute of Telematics and Electronics A
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• v.31A no.9
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• pp.104-113
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• 1994

We have fabricated n-p-n HBTs using 3-inchAlgaAs/GaAs hetero structure epi-wafers grown by MBE. DC and AC characteristics of HBT devices were measured and analyzed. For HBT epi-structure, Al composition of emitter was graded in the region between emitter cap and emitter. And base layer was designed with concentration of 1${\times}10^{19}/cm^{3}$ and thickness of 50nm, and Be was used as the p-type dopant. Principal processes for device fabrication consist of photolithography using i-line stepper, wet mesa etching, and lift-off of each ohmic metal. The PECVD SiN film was used as the inslator for the metal interconnection. HBT device with emitter size of 3${\times}10{\mu}m^{2}$ resulted in cut-off frequency of 35GHz, maximum oscillation frequency of 21GHz, and current gain of 60. The distribution of the ideality factor of collector and base current was very uniform, and the average values of off-set voltage and current was very uniform, and the average values of off-set voltage and current gain were 0.32V and 32 within a 3-inch wafer.

• Proceedings of the KIEE Conference
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• 1995.11a
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• pp.348-351
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• 1995

A modified silicon direct bonding method has been developed alloying an intimate contact between grooved and smooth mirror-polished oxide-free silicon wafers. A regular set of grooves was formed during preparation of heavily doped $p^+$-type grid network by oxide-masking und boron diffusion. Void-free bonded interfaces with filing of the grooves were observed by x-ray diffraction topography, infrared, optical. and scanning electron microscope techniques. The presence of regularly formed grooves in bending plane results in the substantial decrease of dislocation over large areas near the interface. Moreover two strongly misoriented waters could be successfully bonded by new technique. Diodes with bonded a pn-junction yielded a value of the ideality factor n about 1.5 and the uniform distribution of series resistance over the whole area of horded pn-structure. The suitability of the modified technique was confirmed by I - V characteristics of power diodes and reversly switched-on dynistor(RSD) with a working area about $12cm^2$. Both devices demonstrated breakdown voltages close to the calculation values.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.33 no.2
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• pp.155-160
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• 2020

Ga₂O₃/n-type 4H-SiC heterojunction diodes were fabricated by RF magnetron sputtering. The optical properties of Ga₂O₃ and electrical properties of diodes were investigated. I-V characteristics were compared with simulation data from the Atlas software. The band gap of Ga₂O₃ was changed from 5.01 eV to 4.88 eV through oxygen annealing. The doping concentration of Ga₂O₃ was extracted from C-V characteristics. The annealed oxygen exhibited twice higher doping concentration. The annealed diodes showed improved turn-on voltage (0.99 V) and lower leakage current (3 pA). Furthermore, the oxygen-annealed diodes exhibited a temperature cross-point when temperature increased, and its ideality factor was lower than that of as-grown diodes.