• The Transactions of the Korean Institute of Electrical Engineers C
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• v.49 no.2
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• pp.107-112
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• 2000

$(Sr_{0.85}Ca_{0.15})TiO_3$(SCT) thin films were deposited on Pt-coated $TiO_2/SiO_2/Si$ wafer by the rf sputtering method. Experiments were conducted to investigate the electrical properties of SCT thin films with various top electrodes. Various top electrodes as Pt, Al, Ag, Cu were deposited on SCT thin films by sputter and thermal evaporator. The characteristics of C-F and C-V of SCT thin films were not obviously varied with various top electrodes, SCT thin films annealed at $600^{\circ}C$ represents as favorable capacitance characteristics than SCT thin films not annealed, and Pt top electrode have the most high capacitance. The characteristic of I-V of SCT thin films showed that Pt top electrode revealed more less leakage current density than other electrodes, had a leakage current density below 10-8$[A/cm^2]$ until 25[V] applied voltage.

• Journal of the Korean Ceramic Society
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• v.40 no.12
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• pp.1189-1196
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• 2003

Ferroelectric B $i_{3.25}$L $a_{0.75}$ $Ti_3$ $O_{12}$ (BLT) solution was synthesized by sol-gel process. BLT thin films were deposited on Pt/Ti $O_2$/ $SiO_2$/Si substrates by spin-coating. In this experiments, Bi(TMHD)$_3$, La(III)2-Methoxyethoxide, and Ti(IV) i-propoxide were used as starting materials, which were dissolved in 2-Methoxyethanol. Rapid Thermal Annealing (RTA) was used to promote crystallization of BLT thin films. The thin films with RTA process were compared with those with non-RTA process on electrical properties. After RTA process, the remanent polarization value (2Pr) of BLT thin films annealed at 72$0^{\circ}C$ was 20.46 $\mu$C/$\textrm{cm}^2$ which was approximately 27% higher than that of non-RTA process at 5 V.

• Korean Journal of Materials Research
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• v.1 no.1
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• pp.17-22
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• 1991

Tantalum thin films were deposited by DC sputtering on heavily doped single Si substrates. These substrates were treated by means of a rapid thermal annealing (RTA) under Ar atmosphere for various temperatures($600-1100^{\circ}C$). The silicide formation and the impurities behavior in the substrate are studied by means of XRD, SEM, four-point probe, HP4145, and SIMS. The formation of $TaSi_2$ started at $800^{\circ}C$ for all kinds of impurities and the entire Tantalum thin metal films were transformed into $TaSi_2$ above $1000^{\circ}C$ Also the contact resistance for $TaSi_2/P^+$ region had a low value; $22{\Omega}$, at contact site of $0.9{\times}0.9(\mu\textrm{m^2}$), and implanted impurities were diffused out into the $TaSi_2$ for rapid thermal annealing.

• Journal of Sensor Science and Technology
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• v.26 no.6
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• pp.438-444
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• 2017

In this paper, we focus on optimization of the in-situ phosphorous (P) doping of low-pressure chemical vapor deposited (LPCVD) poly Si resistors for obtaining near-zero temperature coefficient of resistance (TCR) at temperature range from 25 to $600^{\circ}C$. The deposited poly Si films were annealed by rapid thermal anneal (RTA) process at the temperature range from 900 to $1000^{\circ}C$ for 90s in nitrogen ambient to relieve intrinsic stress and decrease the TCR in the poly Si layer and get the Ohmic contact. After the RTA process, a roughness of the thin film was slightly changed but the grain size and crystallinity of the thin film with the increase in anneal temperature. The film annealed at $1,000^{\circ}C$ showed the behavior of Schottky contact and had dislocations in the films. Ohmic contact and TCR of $334.4{\pm}8.2$ (ppm/K) within 4 inch wafer were obtained in the measuring temperature range of 25 to $600^{\circ}C$ for the optimized 200 nm thick-poly Si film with width/length of $20{\mu}m/1,800{\mu}m$. This shows the potential of in-situ P doped LPCVD poly Si as a resistor for pressure sensor in harsh environment applications.

• Proceedings of the KIEE Conference
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• 1999.07d
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• pp.1879-1881
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• 1999

(Ba,Sr)$TiO_3$[BST] thin films were fabricated on Pt/Ti/$SiO_2$/Si substrate by RF sputtering. We investigated the effects of substrate temperature on the structural and dielectric properties of BST thin films. Increasing the substrate temperature, barium multi titanate phases were decreased, and BST (100), (200) peaks were increased. The relative dielectric constant and dielectric loss of the BST thin films at the substrate temperature of $500^{\circ}C$ were 300 and 0.018, respectively at l[kHz]. In all films, the dielectric constants decreased. Dielectric losses increased as increasing the frequency. The switching voltage was 5V of the BST thin films at the substrate temperature of $500^{\circ}C$.

• Journal of Advanced Marine Engineering and Technology
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• v.30 no.8
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• pp.927-933
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• 2006

The structural and electrical characteristics of PLZT thin films fabricated onto $Pt/IrO_2/Ir/Ti/SiO_2/Si$ substrates by a pulsed laser deposition were investigated to develop the high dielectric thin films for capacitor layer of semiconductor memory devices The slim region 14/50/50 PLZT thin films were fabricated by PLD and estimated the characteristics for memory application 14/50/50 PLZT thin films have crystallize into perovskite structure at the $600^{\circ}C$ deposition temperature, 200 mTorr of oxygen pressure, and 2 $J/cm^2$ of laser energy density. In this condition PLZT thin films had the dielectric constant as high as 985, storage charge density 8.17 ${\mu}C/cm^2$ and charging time 0.20 ns. Leakage current density was less than $10^{-10}A/cm^2$ up to 5 V bias voltage.

• Korean Journal of Materials Research
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• v.1 no.1
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• pp.54-61
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• 1991

YBCO films deposited on MgO(100) and Si(100) by rf-magnetron sputtering using stoichiometric single target were annealed under oxygen atmosphere at $880^{\circ}C$ for 1 hr. The microstructure and superconducting properties of YBCO thin films depended on the composition of pre-annealed thin films. Basal planesuperconducting particles grown on MgO(100) substrate had small and rod-like shade due to preferred orientation, while superconducting film grown on the basal plane-superconducting particles showed round-shape particles. If pre-annealed thin film had nonstoichiometric composition, liquid phase was formed during the heat treatment, which made it easy for particles to grow in the preferred orientation and thus to form textured structure. But the thin films with the textured structure did not show good superconducting properties, especially $T_c$, since the liquid phase transformed into second phase in the grain boundary during the cooling. The effect of the second phase on $T_{c, \;zero}$ was greater than that on $T_{c, \;on}$.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2003.11a
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• pp.267-270
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• 2003

We have studied the interfacial diffusion phenomena and the role of ${\alpha}-Al_2O_3$ buffer layer as a diffusion barrier in the $Ba-ferrite/SiO_2$ magnetic thin films for high-density recording media. In the interface of amorphous Ba-ferrite ($1900-{\AA}-thick)/SiO_2$ thin film during annealing, the interfacial diffusion started to occur at ${\sim}700^{\circ}C$. As the annealing temperature increased up to $800^{\circ}C$, the interfacial diffusion abruptly proceeded resulting in the high interface roughness and the deterioration of the magnetic properties. In order to control the interfacial diffusion at the high temperature, we introduced ${\alpha}-Al_2O_3$ buffer layer ($110-{\AA}-thick$) in the interface of $Ba-ferrite/SiO_2$ thin film. During the annealing of $Ba-ferrite/{\alpha}-Al_2O_3/SiO_2$ thin film even at ${\sim}800^{\circ}C$, the interface was very smooth. The smooth interface of the film was also clearly shown by the cross-sectional FESEM. The magnetic properties, such as saturation magnetization 3nd intrinsic coercivity, were also enhanced, due to the inhibition of interfacial diffusion by the ${\alpha}-Al_2O_3$ buffer layer. Our study suggests that the ${\alpha}-Al_2O_3$ buffer layer act as a useful interfacial diffusion barrier in the $Ba-ferrite/SiO_2$ thin films.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2002.07b
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• pp.861-864
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• 2002

Ferroelectric $Bi_{4-x}Nd_xTi_3O_{12}$(BNdT) thin films with the composition(x=0.75) were prepared on pt/Ti/$SiO_2$/Si(100) substrate by metal-organic deposition. The electrical and structural characteristics of BNdT thin films were investigated to develop ferroelectric thin films for capacitor layers of FRAM. After spin coating, thin films were annealed at $650^{\circ}C$ for 1hour in oxygen atmosphere. Scanning electron micrographs showed uniform surfaces composed of rod-like grains. The $Bi_{4-x}Nd_xTi_3O_{12}$(X=0.75) thin film capacitors with a Pt top electrode showed better ferroelectric properties. At the applied voltage of 5V, the dielectric constant$(\varepsilon_r)$, dissipation factor$(tan{\delta})$, remanent polarization(2Pr) and nonvolatile swiching charge of the $Bi_{4-x}Nd_xTi_3O_{12}$(x=0.75)thin films were about 346.7, 0.095, $56{\mu}C/cm^2$ and $38{\mu}C/cm^2$ respectively. Also the capacitor did not show any significant fatigue up to $8{\times}10^{10}$ read/write switching cycles at a frequency of 1MHz.

• Journal of the Korean Ceramic Society
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• v.42 no.3 s.274
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• pp.150-154
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• 2005

Ferroelectric $Bi_{3.35}Sm_{0.65}Ti_{3}O_{12}(BSmT)$ thin films were synthesized by sol-gel process. In this experiments, $Bi(TMHD)_{3},\;Sm_{5}(O^{i}Pr)_{13},\;Ti(O^{i}Pr)_4$ were used as precursors, which were dissolved in 2-methoxyethanol. The BSmT thin films were deposited on the Pt/TiO/SiO/Si substrates by spin-coating. Thereafter, the thin films with the thickness of 240 nm were annealed from 600 to $720^{\circ}C$ in oxygen atmosphere for 1 h, and post-annealed in oxygen atmosphere for 1 h after deposition of Pt electrode to enhance the electrical properties. To investigate the effects of Sm-substitution in the BTO thin films, the BTO and BSmT thin films were prepared, respectively. The remanent polarization and coercive voltage of the BSmT thin films annealed at $720^{\circ}C$ were $19.48{\mu}C/cm^2$ and 3.40 V, respectively.