• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2009.06a
• /
• pp.194-194
• /
• 2009

3C-SiC thin films are widely used in extreme environments, radio frequency (RF) environments, and bio-materials for micro/nano electronic mechanical systems (M/NEMS). The mechanical properties of 3C-SiC thin films need to be considered when designing M/NEMS, so Young's Modulus and the hardness need to be accurately measured. Young's Modulus and the hardness are influenced by N-doping. In this paper, we show that the mechanical properties of poly (polycrystalline) 3C-SiC thin films are influenced by the N-doping concentration. Furthermore, we measure the mechanical properties of 3C-SiC thin films for N-doping concentrations of 1%, 3%, and 5%, by using nanoindentation. For films deposited using a 1% N-doping concentration, Young's Modulus and the hardness were measured as 270 GPa and 30 GPa, respectively. When the surface roughness of the thin films was investigated by using atomic force microscopy (AFM), the roughness of the 5% N-doped 3C-SiC thin film was the lowest of all the films, at 15 nm.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2008.11a
• /
• pp.273-273
• /
• 2008

This paper describes the frequency response of two-port surface acoustic wave (SAW) resonator made of 002-polycrystalline aluminum nitride (AlN) thin film on 111-poly 3C-SiC buffer layer. In there, Polycrystalline AlN thin films were deposited on polycrystalline 3C-SiC buffer layer by pulsed reactive magnetron sputtering system, the polycrystalline 3C-SiC was grown on $SiO_2$/Si sample by CVD. The obtained results such as the temperature coefficient of frequency (TCF) of the device is about from 15.9 to 18.5 ppm/$^{\circ}C$, the change in resonance frequency is approximately linear (30-$150^{\circ}C$), which resonance frequency of AlN/3C-SiC structure has high temperature stability. The characteristics of AlN thin films grown on 3C-SiC buffer layer are also evaluated by using the XRD, and AFM images.

• Bulletin of the Korean Chemical Society
• /
• v.28 no.4
• /
• pp.533-537
• /
• 2007

This paper describes the heteroepitaxial growth of single-crystalline 3C-SiC (cubic silicon carbide) thin films on Si (100) wafers by atmospheric pressure chemical vapor deposition (APCVD) at 1350 oC for micro/nanoelectromechanical system (M/NEMS) applications, in which hexamethyldisilane (HMDS, Si2(CH3)6) was used as a safe organosilane single-source precursor. The HMDS flow rate was 0.5 sccm and the H2 carrier gas flow rate was 2.5 slm. The HMDS flow rate was important in obtaing a mirror-like crystalline surface. The growth rate of the 3C-SiC film in this work was 4.3 μm/h. A 3C-SiC epitaxial film grown on the Si (100) substrate was characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), reflection high energy electron diffraction (RHEED), atomic force microscopy (AFM), X-ray photoelectron spectroscopy (XPS) and Raman scattering, respectively. These results show that the main chemical components of the grown film were single-crystalline 3C-SiC layers. The 3C-SiC film had a very good crystal quality without twins, defects or dislocations, and a very low residual stress.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2007.06a
• /
• pp.331-332
• /
• 2007

Surface micromachined SiC devices have readily been fabricated from the polycrystalline (poly) 3C-SiC thin film which has an advantage of being deposited onto $SiO_2$ or $Si_3N_4$ as a sacrificial layer. Therefore, in this work, magnetron reactive ion etching process which can stably etch poly 3C-SiC thin films grown on $SiO_2$/Si substrate at a lower energy (70 W) with $CHF_3$ based gas mixtures has been studied. We have investigated the etching properties of the poly 3C-SiC thin film using PR/Al mask, according to $O_2$ flow rate, pressure, RF power, and electrode gap. The etched RMS (root mean square), etch rate, and etch profile of the poly 3C-SiC thin films were analyzed by SEM, AFM, and $\alpha$-step.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
• /
• v.23 no.2
• /
• pp.98-102
• /
• 2010

This paper describes that single crystalline 3C-SiC (cubic silicon carbide) thin films have been deposited on carbonized Si(100) substrates using hexamethyldisilane (HMDS, $Si_2(CH_3){_6}$) as a safe organosilane single precursor and a nonflammable mixture of Ar and $H_2$ gas as the carrier gas by APCVD at $1280^{\circ}C$. The deposition was performed under various conditions to determine the optimized growth condition. The crystallinity of the 3C-SiC thin film was analyzed by XRD (X-ray diffraction). The surface morphology was also observed by AFM (atomic force microscopy) and voids between SiC and Si interfaces were measured by SEM (scanning electron microscopy). Finally, residual strain and hall mobility was investigated by surface profiler and hall measurement, respectively. From these results, the single crystalline 3C-SiC film had a good crystal quality without defects due to viods, a low residual stress, a very low roughness.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2007.11a
• /
• pp.89-90
• /
• 2007

This paper presents the mechanical properties of 3C-SiC thin film according to 0, 7, and 10% carrier gas $(H_2)$ concentrations using Nano Indentation. When carrier gas $(H_2)$ concentration was 10%, it has been proved that the mechanical properties, elastic modulus and hardness, of 3C-SiC are the best of them. In the case of 10% carrier gas concentration, Young's modulus and Hardness were obtained as 367 GPa and 36 GPa, respectively. When the surface roughness according to $H_2$ concentrations was investigated by AFM (atomic force microscope), when $H_2$ concentration was 10%, the roughness of 3C-SiC thin was 9.92 nm, which is also the best of them. Therefore, in order to apply poly 3C-SiC thin film to MEMS applications, $H_2$ concentration's rate should increase to obtain better mechanical properties and surface roughness.

• Korean Journal of Materials Research
• /
• v.13 no.3
• /
• pp.174-179
• /
• 2003

Thin copper films were grown by electrodeposition on copper seed layers which were grown by sputtering of an ultra-pure copper target on tantalum nitride-coated silicon wafers and subsequently, cleaned in ECR plasma. The copper films were then subjected to ⅰ) vacuum annealing, ⅱ) rapid thermal annealing (RTA) and ⅲ) rapid thermal nitriding (RTN) at various temperatures over different periods of time. XRD, SEM, AFM and resistivity measurements were done to ascertain the optimum heat treatment condition for obtaining film with minimum resistivity, predominantly (111)-oriented and smoother surface morphology. The as-deposited film has a resistivity of ∼6.3 $\mu$$\Omega$-cm and a relatively small intensity ratio of (111) and (200) peaks. With heat treatment, the resistivity decreases and the (111) peak becomes dominant, along with improved smoothness of the copper film. The optimum condition (with a resistivity of 1.98 $\mu$$\Omega$-cm) is suggested as the rapid thermal nitriding at 400oC for 120 sec.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2009.11a
• /
• pp.184-184
• /
• 2009

This paper introduces the characteristics of SnO2 inorganic film deposited by radio-frequency magnetron sputtering as an alternative alignment layer for liquid crystal display (LCD) applications. The pretilt angle of the SnO2 layer was shown to be a function of the ion beam(IB) incident angle, a planer alignment of nematic liquid crystal was achieved. The about $1.8^{\circ}$ of stable pretilt angle was achieved at the range from 1500 ~ 2500eV of incident energy. To characterize the film shows atomic force microscopy (AFM) on the IB irradiated SnO2 surfaceand the X-ray phtoelectron spectroscopy analysis showed that the liquid crystal(LC) alignment on the IB irradiated $SnO_2$ surface was due to the reformation of Sn-O bonds. Also, Figure 1 shows that The alignment capability of the IB irradiated SnO2 layers is maintained until annealing temperature of $200^{\circ}C$. Comparable electro-optical characteristics to rubbed polyimide were also achieved.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
• /
• v.13 no.12
• /
• pp.1032-1038
• /
• 2000

Ni$_{81}$$Fe_{19}$(200 nm) thin films have been deposited by RF-magnetron sputtering on Si(001) substrates, Atomic force microscopy(AFM), X-ray diffraction(XRD) and magnetoresistance(MR) measurements of the thin films for investigating electromagnetic properties and microstructures were employed. During field annelaing for 1hr, there was no big difference n XRD patterns of Ni$_{81}$$Fe_{19}$ thin films. However, there was a significant change in XRD patterns of Ni$_{81}$$Fe_{19}$ thin films deposited at 40$0^{\circ}C$ during in-situ magnetic field deposition. The degree of surface roughness increased with increasing annealing and deposition temperature. With variation of surface roughness, there was no significant difference in MR Characteristics of Ni$_{18}$ $Fe_{19}$ thin films in 1hr-annealed case. High MR ratio was observed in the case of in-situ field deposited Ni$_{81}$$Fe_{19}$ films. 19/ films.

• Tribology and Lubricants
• /
• v.24 no.2
• /
• pp.77-81
• /
• 2008

In this work, ramp loading scratch method was used to evaluate the scratch characteristics of HDD media and ZnO thin films. Commercially available HDD media and ZnO thin films grown on silicon(100) substrate by sol-gel method were used. As for the ZnO films, the effects of annealing temperature after the film deposition process were also investigated. A custom built scratch tester was used to scratch the specimen under a ramp loading condition. The scratch track formed by ramp loading was measured by optical microscope and Atomic Force Microscopy (AFM). The wear depth and width were used to assess the scratch characteristics of the HDD Media and ZnO thin films. The results showed that ZnO film annealed at $800^{\circ}C$ had the best scratch resistance property. Also, the HDD media showed overall better scratch resistance than the ZnO films.