• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2002년도 하계학술대회 논문집
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• pp.305-309
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• 2002

We have successfully fabricated a Metal-Ferroelectric-Insulator-Semiconductor (MFIS) structure using Bi$\sub$4-x/La$\sub$x/Ti$_3$O$\sub$12/ (BLT) ferroelectric thin film and SiO$_2$/Nitride/SiO$_2$ (ONO) stacked buffer layers for single transistor type ferroelectric nonvolatile memory applications. BLT films were deposited on 15 nm-thick ONO buffer layer by sol-gel spin-coating. The dielectric constant and the leakage current density of prepared ONO film were measured to be 5.6 and 1.0 x 10$\^$-8/ A/$\textrm{cm}^2$ at 2MV/cm, respectively, It was interesting to note that the crystallographic orientations of BLT thin films were strongly effected by pre-bake temperatures. X-ray diffraction patterns showed that (117) crystallites were mainly detected in the BLT film if pre-baked below 400$^{\circ}C$. Whereas, for the films pre-baked above 500$^{\circ}C$, the crystallites with preferred c-axis orientation were mainly detected. From the C-V measurement of the MFIS capacitor with c-axis oriented BLT films, the memory window of 0.6 V was obtained at a voltage sweep of ${\pm}$8 V, which evidently reflects the ferroelectric memory effect of a BLT/ONO/Si structure.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 1998년도 하계종합학술대회논문집
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• pp.343-346
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• 1998

Ultra-thin gate oxide in MOS devices are subjected to high-field stress during device operation, which degrades the oxide and exentually causes dielectric breakdown. In this paper, we investigate the electrical properties of ultra-thin nitrided oxide (NO) and reoxidized nitrided oxide(ONO) films that are considered to be promising candidates for replacing conventional silicon dioxide film in ULSI level integration. We study vriations of I-V characteristics due to F-N tunneling, and time-dependent dielectric breakdown (TDDB) of thin layer NO and ONO depending on nitridation and reoxidation condition, and compare with thermal $SiO_{2}$. From the measurement results, we find that these NO and ONO thin films are strongly depending on its condition and that optimized reoxided nitrided oxides (ONO) films show superior dielectric characteristics, and breakdown-to-change ( $Q_{bd}$ ) performance over the NO films, while maintaining a similar electric field dependence compared to NO layer.

• 한국진공학회지
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• 제3권1호
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• pp.71-76
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• 1994

The electrical characteristics of the capacitor dielectric films of amorphous silicon-nit-ride-oxide(ANO) structures are compared with the capacitor dielectric films of oxide-nitride-oxide (ONO) structrues The electrical characteristics of ONO and ANO films were evaluated by high frequency(1 MHz) C-V high frequency C-V after constant voltage stree I-V TDDB and refresh time measurements. ANO films shows good electrical characteristics such as higher total charge to breakdown storage capacitance and longer refresh time than ONO films. Also it makes little difference that leakage current and flat band voltage shyift(ΔVfb)of ANO ana ONO films.

• 한국전기전자재료학회논문지
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• 제16권12호
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• pp.1065-1070
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• 2003

HTO(High Temperature Oxide) films are mainly used as a gate insulator for polysilicon thin film transistors(Poly-Si TFT's). The HTO films, however, show the demerits of a high leakage current and a low electric breakdown voltage comparing with conventional thermal oxides even though they have a better surface in roughness than the thermal oxides. In this paper, we propose an ONO(Oxide-Nitride-Oxide) multilayer as the gate insulator for poly-Si TFT's. The leakage current and electric breakdown voltage of the ONO and HTO were measured. The drain current variation of poly-Si TFT's with a variety of gate insulators was observed. The thickness optimization in ONO films was carried out by studying I$\_$on/I$\_$off/ ratio of the poly-Si TFT's as a function of the thickness of ONO film adopted as gate insulator.

• 한국정보통신학회논문지
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• 제2권3호
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• pp.431-437
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• 1998

본 논문에서는, ULSI에서 기존의 실리콘 절연막을 대체할 것으로 여겨지는 질화 산화막(NO)과 재산화 질화 산화막(ONO)의 전기적 특성을 조사하였다. 특히, 질화 및 재산화 시간에 따른 NO와 ONO막의 전류전압 특성, 게이트 전압이동, 시간종속 절연항복 특성(TDDB) 변화를 측정하였고, 외부 온도 변화에 따른 최적화 된NO와 ONO막의 누설 전류와 절연체가 항복에 이르게 하는 전하량(Q$\_bd$)변화를 측정하였다. 그런 다음 기존의SIO$\_2$와 비교하였다. 측정 결과로부터, NO와 ONO막은 공정시간에 상당히 의존적이었으며, 최적화된 ONO막은 같은 전계를 유지하는 동안 절연 특성 및 Q$\_bd$특성에서 NO막과 SIO$\_2$에 비하여 우수한 성능을 보였다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1998년도 춘계학술대회 논문집
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• pp.79-82
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• 1998

Film characteristics of thin ONO dielectric layers for MONOS(metal-oxide-nitride-oxide-semiconductor) EEPRM was investigated by AES and AFM. Second derivative spectra of AES Si LVV overlapping peak provided useful information for chemical state analysis of superthin film. The ONO films with dimension of tunneling oxide 24${\AA}$, nitride 33${\AA}$, and blocking oxide 40${\AA}$ were fabricated. During deposition of the LPCVD nitride films on tunneling oxide, this thin oxide was nitrized. When the blocking oxide were deposited on the nitride film, the oxygen not only oxidized the nitride surface, but diffused through the nitride. The results of ONO film analysis exhibits that it is made up of SiO$_2$(blocking oxide)/O-rich SiON(interface/N-rich SiON(nitride)/-rich SiON(interface)/N-rich SiON(nitride)/O-rich SiON(tunneling oxide).

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1998년도 추계학술대회 논문집
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• pp.1-4
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• 1998

In this paper, we have studied a variation of I-V characteristics, and time-dependent dielectric breakdown(TDDB) of thin layer NO and ONO film depending on nitridation and reoxidation time, respectively, and measured a variation of leakage current and charge-to-breakdown(Q$\_$bd/) of optimized NO and ONO film depending on ambient temperature, and then compared with the properties of conventional SiO$_2$. From the results, we find that these NO and ONO thin films are strongly influenced by process time and the optimized ONO film shows superior dielectric characteristics, and Q$\_$bd/ performance over the NO film and SiO$_2$, while maintaining a similar electric field dependence compared with NO layer.

• 한국결정성장학회지
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• 제8권3호
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• pp.424-430
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• 1998

MONOS(metal-oxide-nitride-oxide-semicondutor) EEPROM에 응용하기 위한 얇은 ONO 유전층의 막 특성을 AES, SIMS, TEM 및 AFM을 이용하여 조사하였다. 터널링 산화막, 질화막, 블로킹 산화막의 두께를 각각 달리하여 ONO 박막을 제작하였다. 터널링 산화막 위에 LPCVD방법으로 질화막을 증착하는 동안 얇은 터널링 산화막이 질화되었으며, 질화막 위에 블로킹 산화막을 형성할 때, 산소가 질화막 표면을 산화시킬 뿐만 아니라 질화막을 지나 확산되었다. ONO 박막은 $SiO_2$(블로킹 산화막)/O-rich SiOxNy(계면)/N-rich iOxNy(질화막)/O-rich SiOxNy(터널링 산화막)으로 이루어졌다. SiON상은 주로 터널링 산화막과 질화막, 질화막과 블로킹 산화막 계면에 분포하였으며, $Si_2NO$상은 각 계면의 질화막 쪽과 터널링 산화막 내에 분포하였다.

• 센서학회지
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• 제16권2호
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• pp.159-164
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• 2007

Thin films of platinum were deposited on a $Al_{2}O_{3}/ONO(SiO_{2}-Si_{3}N_{4}-SiO_{2})/Si$-substrate with an 2-inch Pt(99.99 %) target at room temperature for 20, 30 and 60 min by DC magnetron sputtering, respectively X-ray diffract meter (XRD) was used to analyze the crystallanity of the thin films and field emission scanning electron microscopy (FE-SEM) was employed for the investigation on crystal growth. The densification and the grain growth of the sputtered films have a considerable effect on sputtering time and annealing temperatures. The resistance of the Pt thin films was decreased with increasing deposition time and sintering temperature. Pt micro heater thin film deposited for 60 min by DC magnetron sputtering on an $Al_{2}O_{3}$/ONO-Si substrate and annealed at $600^{\circ}C$ for 1 h in air is found to be a most suitable micro heater with a generation capacity of $350^{\circ}C$ temperature and 645 mW power at 5.0 V input voltage. Adherence of Pt thin film and $Al_{2}O_{3}$ substrate was also found excellent. This characteristic is in good agreement with the uniform densification and good crystallanity of the Pt film. Efforts are on progress to find the parameters further reduce the power consumption and the results will be presented as soon as possible.

• 한국표면공학회지
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• 제29권6호
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• pp.857-861
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• 1996

The influence of rf-plasma operation on the thin film formation containing small particles for Al-Li alloys mainly have been studied as a function of Ar gas pressure and plasma power by means of a 200kV transmission electron microscope (TEM). Under the non-plasma operation, the transition from continuous thin films to clusters of grape-like small particles occurred at Ar gas pressures above 20Pa. Particles were single crystals with clear crystal habit planes. Under the plasma operation, the influence of gas pressures on the film formation at a plasma power of 5W was also examined. Thin films containing particles below 30Pa and the films containing mainly particles above 40Pa were formed. The prominent change of the average particle size was not recognized. The increase of the plasma powers at 20Pa, which formed particles under non-plasma, suppressed growth of particles, and homogeneous films containing very small particles were fabricated. The electric conductivity showed slight decrease with an increase of plasma power.