• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.19 no.8
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• pp.732-736
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• 2006

This paper describes the physical characterizations of polycrystalline 3C-SiC thin films heteroepitaxially grown on Si wafers with thermal oxide, In this work, the 3C-SiC film was deposited by LPCVD (low pressure chemical vapor deposition) method using single precursor 1, 3-disilabutane $(DSB:\;H_3Si-CH_2-SiH_2-CH_3)\;at\;850^{\circ}C$. The crystallinity of the 3C-SiC thin film was analyzed by XPS (X-ray photoelectron spectroscopy), XRD (X-ray diffraction) and FT-IR (fourier transform-infrared spectometers), respectively. The surface morphology was also observed by AFM (atomic force microscopy) and voids or dislocations between SiC and $SiO_2$ were measured by SEM (scanning electron microscope). Finally, residual strain was investigated by Raman scattering and a peak of the energy level was less than other type SiC films, From these results, the grown poly 3C-SiC thin film is very good crystalline quality, surface like mirror, and low defect and strain. Therefore, the polycrystalline 3C-SiC is suitable for harsh environment MEMS (Micro-Electro-Mechanical-Systems) applications.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2008.11a
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• pp.93-93
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• 2008

This paper presents the Raman scattering characteristics of poly (polycrystalline) 3C-SiC thin films deposited on AlN buffer layer by atmospheric pressure chemical vapor deposition (APCVD) using hexamethyldisilane (MHDS) and carrier gases (Ar + $H_2$).The Raman spectra of SiC films deposited on AlN layer of before and after annealings were investigated according to the growth temperature of 3C-SiC. Two strong Raman peaks, which mean that poly 3C-SiC admixed with nanoparticle graphite, were measured in them. The biaxial stress of poly 3C-SiC/AlN was calculated as 896 MPa from the Raman shifts of 3C-SiC deposited at $1180^{\circ}C$ on AlN of after annealing.

• Journal of Sensor Science and Technology
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• v.18 no.3
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• pp.207-209
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• 2009

This paper describes the characteristics of poly 3C-SiC micro resonators with $3{\times}10^{17}{\sim}1{\times}10^{19}cm^{-3}$ doping concentrations. The 1.2 ${\mu}m$ thick cantilever and the 0.4 ${\mu}m$ thick doubly clamped beam resonators with different lengths were fabricated using poly 3C-SiC thin films. The characteristics of poly 3C-SiC micro resonators were evaluated by quartz and a laser vibrometer in vacuum at room temperature. The resonant frequencies of micro resonators decreased with doping concentrations owing to reduction in the Young's modulus of poly 3C-SiC thin films. It was confirmed that the resonant frequencies of poly 3C-SiC resonators are controllable by doping concentrations. Therefore, poly 3C-SiC resonators could be applied to MEMS devices and bio/chemical sensor applications.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2007.06a
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• pp.333-334
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• 2007

This paper describes the characteristics of poly (polycrystalline) 3C-SiC grown on SiOz and AlN substrates, respectively. The crystalline quality of poly 3C-SiC was improved from resulting in decrease of FWHM (full width half maximum) of XRD by increasing the growth temperature. The minimum growth temperature of poly 3C-SiC was $1100^{\circ}C$. The surface chemical composition and the electron mobility of poly 3C-SiC grown on each substrate were investigated by XPS and Hall Effect, respectively. The chemical compositions of surface of poly 3C-SiC films grown on $SiO_2$ and AlN were not different. However, their electron mobilities were $7.65\;cm^2/V.s$ and $14.8\;cm^2/V.s$, respectively. Therefore, since the electron mobility of poly 3C-SiC films grown on AlN buffer layer was two times higher than that of 3C-SiC/$SiO_2$, a AlN film is a suitable material, as buffer layer, for the growth of poly 3C-SiC thin films with excellent properties for M/NEMS applications.

• Journal of IKEEE
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• v.26 no.1
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• pp.111-118
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• 2022

In this paper, we studied 4H-SiC CMOS that can be integrated with high-voltage SiC power devices. After designing the CMOS on a 4H-SiC substrate, we compared the electrical characteristics with the reliability of high temperature operation by TCAD simulation. In particular, it was confirmed that changing HfO₂ as the gate dielectric for reliable operation at high temperatures improves the thermal properties compared to SiO₂. By researching SiC CMOS devices, we can integrate high-power SiC power devices with SiC CMOS for excellent performance in terms of efficiency and cost of high-power systems.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2008.11a
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• pp.274-274
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• 2008

This paper describes on the fabrication and characteristics of a 3C-SiC (Silicon Carbide) micro pressure sensor for harsh environment applications. The implemented micro pressure sensor used 3C-SiC thin-films heteroepitaxially grown on SOI (Si-on-insulator) structures. This sensor takes advantages of the good mechanical properties of Si as diaphragms fabricated by D-RIE technology and temperature properties of 3C-SiC piezoresistors. The fabricated pressure sensors were tasted at temperature up to $250^{\circ}C$ and indicated a sensitivity of 0.46 mV/V*bar at room temperature and 0.28 mV/V*bar at $250^{\circ}C$. The fabricated 3C-SiC/SOI pressure sensor presents a high-sensitivity and excellent temperature stability.

• Journal of Sensor Science and Technology
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• v.16 no.4
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• pp.259-262
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• 2007

This paper describes the electrical characteristics of polycrystalline (poly) 3C-SiC thin film diodes, in which poly 3C-SiC thin films on n-type and p-type Si wafers, respectively, were deposited by APCVD using HMDS, $H_{2}$, and Ar gas at $1150^{\circ}C$ for 3 hr. The schottky diode with Au/poly 3C-SiC/Si (n-type) structure was fabricated. Its threshold voltage ($V_{bi}$), breakdown voltage, thickness of depletion layer, and doping concentration ($N_{D}$) value were measured as 0.84 V, over 140 V, 61 nm, and $2.7{\times}10^{19}cm^{-3}$, respectively. Moreover, for the good ohmic contact, Al/poly 3C-SiC/Si (n-type) structure was annealed at 300, 400, and $500^{\circ}C$, respectively for 30 min under the vacuum condition of $5.0{\times}10^{-6}$ Torr. Finally, the p-n junction diodes fabricated on the poly 3C-Si/Si (p-type) were obtained like characteristics of single 3CSiC p-n junction diode. Therefore, poly 3C-SiC thin film diodes will be suitable for microsensors in conjunction with Si fabrication technology.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 1998.04a
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• pp.139-145
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• 1998

This paper addresses the R-curve properties, wear resistance, and erosion resistance of the two silicon carbide ceramics with different microstructures, i.e. , fine grained SiC and in situ-toughened SiC(IST SIC). Fine grained SiC exhibits a relatively flat R-curve behavior whereas the IST SiC exhibits a increasing R-curve behavior. The increasing R-curve behavior in IST SiC is attributed to relatively weak grain boundaries. The rate of material removal during wear tests and erosion tests was higher for IST SiC than that for fine grained SiC. This is attributed to the weaker grain boundaries in IST SiC than that in fine grained SiC. It is implied that fracture toughness in short crack regime should be taken into consideration in the interpretation of the microscopical material removal process. We show that the higher the strength of grain boundaries is, the higher wear and erosion resistances are.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.23 no.6
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• pp.487-490
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• 2010

This paper describes the elecrtical and optical characteristics of $N_2$ doped porous 3C-SiC films. Polycrystalline 3C-SiC thin films are anodized by $HF+C_2H_5OH$ solution with UV-LED exposure. The growth of in-situ doped 3C-SiC thin films on p-type Si (100) wafers is carried out by using APCVD (atmospheric pressure chemical vapor deposition) with a single-precursor of HMDS (hexamethyildisilane: $Si_2(CH_3)_6)$. 0 ~ 40 sccm $N_2$ was used for doping. After the growth of doped 3C-SiC, porous 3C-SiC is formed by anodization with $7.1\;mA/cm^2$ current density for anodization time of 60 sec. The average pore diameter is about 30 nm, and etched area is increased with $N_2$ doping rate. These results are attributed to the decrease of crystallinity by $N_2$ doping. Mobility is dramatically decreased in porous 3C-SiC. The band gaps of polycrystalline 3C-SiC films and doped porous 3C-SiC are 2.5 eV and 2.7 eV, respectively.

• Journal of the Korean Ceramic Society
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• v.19 no.2
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• pp.121-126
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• 1982

This paper deals with the $Si_3N_4$-bonded SiC refractory in terms of its microstructure development during nitridation. When mixture of SiC grains and fine Si power is fired under nitrogen atmosphere, an interlocking network of $Si_3N_4$ whiskers is formed by nitridation of Si. It is found that the strength of $Si_3N_4$-bonded SiC refractory is soley due to the physical nature of this interlocking whiskers. At the initial stage of nitridation, $Si_3N_4$ whisker forms in very thin and long shape and, with further nitridation, it becomes thicker with diameters up to 0.35$\mu\textrm{m}$. It is found that the mechanical strength of $Si_3N_4$-bonded SiC refractory depends on the degree of nitridation and the development of microstructure.