• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2000년도 하계종합학술대회 논문집(2)
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• pp.20-23
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• 2000

We have investigated a process for the preparation of high-quality tantalum oxynitride ( $T_{a}$ $O_{x}$ $N_{y}$) via the N $H_3$ annealing of 7$_{a2}$ $O_{5}$, for use in gate dielectric applications. Compared with tantalum oxide (7$_{a2}$ $O_{5}$), a significant improvement in the dielectric constant was obtained by the N $H_3$ treatment. In addition, light reoxidation in a wet ambient at 45$0^{\circ}C$ resulted in a significantly reduced leakage current. We confirmed nitrogen incorporation in the tantalum oxynitride ( $T_{a}$ $O_{x}$ $N_{y}$ by Auger Electron Spectroscopy. By optimizing the nitridation and reoxidation process, we obtained an equivalent oxide thickness as thin as 1.6nm and a leakage current of less than 10mA/$\textrm{cm}^2$ at 1.5V..5V..5V..5V..5V..5V.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1995년도 추계학술대회 논문집
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• pp.48-51
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• 1995

We have developed the three dimensional mesh generator for three dimensional process simulation using the FEM(Finite Element Method). Tetrahedron element construct the presented three dimensional mesh, which is suitable for the simulation of three dimensional behavior of the LOCOS. The simulation of thermal oxidation is one of the problem in scale downed semiconductor processes. As three dimensional simulators use the huge size of the memory, we use the efficient method that generates the new nodes inside the growing oxide and removes the nodes nearby the SiO2/Si interface in silicon. The resented three dimensional mesh generator was designed to be used in various process simulations, for instance thermal oxidation, silicidation, nitridation, ion implantation, diffusion, and so on.

• 한국분말재료학회지
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• 제18권3호
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• pp.238-243
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• 2011

Al/AlN composites were synthesized by mechanical alloying using process control agents(PCAs). Three different PCAs which contain N element, were examined to see the effectiveness of ball-milling and the nitridation during sintering. Among examined PCAs, $C_8H_6N_4O_5$ was the most effective to facilitate ball-milling and to form nitrides during a subsequent sintering. By a proper control of ball-milling and sintering, we could obtained surface-hardened Al-based composites.

• 한국분말재료학회지
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• 제28권2호
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• pp.143-149
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• 2021

In this study, (GaN)_1-x(ZnO)_x solid solution nanoparticles with a high zinc content are prepared by ultrasonic spray pyrolysis and subsequent nitridation. The structure and morphology of the samples are investigated by X-ray diffraction (XRD), field-emission scanning electron microscopy, and energy-dispersive X-ray spectroscopy. The characterization results show a phase transition from the Zn and Ga-based oxides (ZnO or ZnGa₂O₄) to a (GaN)_1-x(ZnO)_x solid solution under an NH3 atmosphere. The effect of the precursor solution concentration and nitridation temperature on the final products are systematically investigated to obtain (GaN)_1-x(ZnO)_x nanoparticles with a high Zn concentration. It is confirmed that the powder synthesized from the solution in which the ratio of Zn and Ga was set to 0.8:0.2, as the initial precursor composition was composed of about 0.8-mole fraction of Zn, similar to the initially set one, through nitriding treatment at 700℃. Besides, the synthesized nanoparticles exhibited the typical XRD pattern of (GaN)_1-x(ZnO)_x, and a strong absorption of visible light with a bandgap energy of approximately 2.78 eV, confirming their potential use as a hydrogen production photocatalyst.

• 한국세라믹학회지
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• 제39권3호
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• pp.272-277
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• 2002

전구체로 ($NH_4)[Al(ethylenediaminetetraacetate)]{\cdot}2H_2O$ 착물을 이용한 수정된 열탄소환원질화법으로 질화알루미늄(AlN) 분말과 휘스커를 합성하였다. 이 분말은 질소분위기에서 별도의 환원용 탄소를 혼합하지 않고 1200$^{\circ}$C에서 1500$^{\circ}$C까지의 온도에서 하소시킨 다름 잔류탄소를 태워 버림으로써 얻어졌다. 이 질화과정을 Al-27 마법각 스핀 핵자기공명, 적외선 분광법 및 X-선 회절법으로 연구했다. 전구체 착물은 열분해되어 ${\rho}$-알루미나와 ${\gamma}$-알루미나로 되었다가 ${\gamma}-{\alpha}$알루미나 전이없이 AlN으로 바뀌었다. ${\gamma}$-알루미나가 AlN으로 바뀌면서 분말의 형상이 유지되는 것으로 보아 이 변환과정에서의 중간체는 알루미늄이나 aluminum suboxides와 같은 기체상이 아니고, 고체상의 $AlO_xN_y$임을 알 수 있다. (0001) 사파이어를 이용하면 AlN 휘스커를 합성할 수 있다.

• Transactions on Electrical and Electronic Materials
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• 제9권1호
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• pp.6-11
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• 2008

In this study, we investigated effects of hydrogen annealing (HA) and plasma nitridation (PN) applied in order to improve $Si/SiO_2$ interface characteristics of TiN metal gate. In result, HA and PN showed a positive effect decreasing number of interface state $(N_{it})$ respectively. After FN stress for verifying reliability, however, we identified rapid increase of $N_{it}$ for TiN gate with HA, which is attributed to hydrogen related to a change of $Si/SiO_2$ interface characteristic. In contrast to HA, PN showed an improved Nit and gate oxide leakage characteristic due to several possible effects, such as blocking of Chlorine (Cl) diffusion and prevention of thermal reaction between TiN and $SiO_2$.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2001년도 추계학술대회 논문집 Vol.14 No.1
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• pp.17-20
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• 2001

Nonvolatile semiconductor memory devices with reoxidized nitrided oxide(RONO) gate dielectrics were fabricated, and nitrogen distribution and bonding species which contribute to memory characteristics were analyzed. Also, memory characteristics of devices depending on the anneal temperatures were investigated. The devices were fabricated by retrograde twin well CMOS processes with $0.35{\mu}m$ Nonvolatile semiconductor memory devices with reoxidized nitrided oxide(RONO) gate dielectric were fabricated, and nitrogen distribution and bonding species which contributing memory characteristics were analyzed. Also, memory characteristics of devices according to anneal temperatures were investigated. The devices were fabricated by $0.35{\mu}m$ retrograde twin well CMOS processes. The processes could be simple by in-situ process of nitridation anneal and reoxidation. The nitrogen distribution and bonding state of gate dielectric were investigated by Dynamic Secondary Ion Mass Spectrometry(D-SIMS), Time-of-Flight Secondary Ion Mass Spectrometry(ToF-SIMS), and X-ray Photoelectron Spectroscopy(XPS). Nitrogen concentrations are proportional to nitridation anneal temperatures and the more time was required to form the same reoxidized layer thickness. ToF-SIMS results show that SiON species are detected at the initial oxide interface and $Si_{2}NO$ species near the new $Si-SiO_{2}$ interface that formed after reoxidation. As the anneal temperatures increased, the device showed worse retention and degradation properties. These could be said that nitrogen concentration near initial interface is limited to a certain quantity, so excess nitrogen are redistributed near the $Si-SiO_{2}$ interface and contributed to electron trap generation.

• 한국진공학회지
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• 제7권s1호
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• pp.85-99
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• 1998

A ultrahigh vacuum chemical vapor deposition(UHVCVD)/metalorganic chemical vapor deposition(MOMBE) system equipped with a radio frequency(RF)-plasma cell was employed to grow GaN layer on the sapphire at a low temperature. The x-ray photoelectron spectroscopy analysis of nitrogen composition on the nitridated sapphite surface indicated that a nitridation process is mostly affected by the RF power at low temperature. Atomic force microscope images of nitridated surface the protrusion density on the nitridated sapphire is dependent on the nitridation temperature. The crystallinity of GaN grown at $450^{\circ}C$ was found to be much improved when the sapphire was nitridated at low temperature prior to the GaN layer growth. Moreover, a strong photoluminescence spectrum of GaN grown by UHVCVD/MOMBE with a rf-nitrogen plasma was observed for the first time at room temperature.

• 한국전기전자재료학회논문지
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• 제21권3호
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• pp.208-212
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• 2008

This paper reports physical properties of in situ boron doped silicon films made from boron source gas and silane ($SiH_4$) gas in a conventional low-pressure chemical vapor deposition vertical furnace. If the p-type polysilicon is formed by boron implantation into undoped polysilicon, the plasma nitridation (PN) process is added on the oxide in order to suppress boron penetration that can be caused during the thermal treatments used in fabrication. In-situ boron doped polysilicon deposition can complete p-type polysilicon film with only one deposition process and need not the PN process, because there is not interdiffusion of dopant at the intermediate temperatures of the subsequent steps. Since in-situ boron doped polysilicon films have higher work function than that of n-type polysilicon and they are compatible with the underlying oxide, they may be promising materials for improving memory cell characteristics if we make its profit of these physical properties.

• 한국세라믹학회지
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• 제46권5호
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• pp.478-483
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• 2009

Thermal shock and hot corrosion resistance of silicon nitride ceramics are investigated in this study. Silicon nitrides are fabricated by nitride pressureless sintering (NPS) process, which process is the continuous process of nitridation reaction of Si metal combined with subsequent pressureless sintering. The results of thermal shock test show it sustains 400MPa of initial strength during test in the designated condition of ${\Delta}T=700{\sim}25^{\circ}C$ up to maximum 4,800 cycles. Hot corrosion tests also reveal that the strength degradation of NPS silicon nitride did not occur at $700^{\circ}C$ with an exposure in Ar, $H_2$, Na and K for 1,275 h.