• 환경위생공학
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• 제15권2호
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• pp.41-48
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• 2000

In this study, we have investigated the effect of the various operating conditions on the removal fluorine in the rinsed water for the semiconductor industry by using electrolysis process. The removal efficiency of fluorine was irrelevant to initial pH, and carbon anode was high-level treatment in the effect of various electrodes. Fluorine included in the wastewater is treated by the addition of a Ca(OH)2, removal efficiency of electrolysis was increased about 40%. Besides the removal efficiency of fluorine was increased as the current density was increased and this treatment system could reduce both the total sludge and running costs. The feasibility of the electrochemical treatment to the fluorine containing wastewater was verified from this study.

• 전자공학회논문지D
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• 제35D권1호
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• pp.27-33
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• 1998

In this study, chlorine(Cl)-based gas chemistry is generally used to etching for AlCu films metallization.The corrosion phenomena of AlCu films were examined with XPS (X-ray photoelectron spectroscopy), SEM 9Scanning electron microscopy), and TEM (Transmission electron microscopy). SF$_{6}$ plasma treatment sulbsequent to the etching process preventas the corrosion effectively in the pressure of 300 mTorr. It is found that the cholrine atoms on the etched surface are not substituted for fluorine atoms during SF$_{6}$ treatment, but a passivation layer on the surface by fluorine-related compounds would be formed. The passivation layer prevents the moisture penetration on the SF$_{6}$ treated surface and suppresses the corrsion sucessfully.fully.

• 한국전기전자재료학회논문지
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• 제11권3호
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• pp.203-207
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• 1998

After etching Al-Cu alloy films using $SiCl_4/Cl_2/He/CHF_3$ plasma, a corrosion phenomenon on the metal surface has been studied with XPS (X-ray photoelectron spectroscopy) and SEM (Scanning electron microscopy). In Al-Cu alloy system, the corrosion occurs rapidly on the etched surface by residual chlorine atoms. To prevent the corrosion, the $SF_6$ plasma treatment subsequent to the etch has been carried out. A passivation layer is formed by fluorine-related compounds on etched Al-Cu alloy surface after $SF_6$ treatment, and the layer suppresses effectively the corrosion on the surface as the RF power of $SF_6$ treatment increases. The corrosion could be suppressed successfully with $SF_6$ treatment in the RF power of 150watts.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1998년도 춘계학술대회 논문집
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• pp.383-386
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• 1998

After etching Al-Cu alloy films using SiC1$_4$/Cl$_2$/He/CHF$_3$ plasma, a corrosion phenomenon on the metal surface has been studied with XPS (X-ray photoelectron spectroscopy) and SEM (Scanning electron microscopy). In Al-Cu alloy system, the corrosion occurs rapidly on the etched surface by residual chlorine atoms. To prevent the corrosion, CHF$_3$ plasma treatment subsequent to the etched has been carried out. A passivation layer is formed by fluorine-related compounds on the etched Al-Cu surface after CHF$_3$ and SF$_{6}$ treatment, and the layer supresses effectively the corrosion on the surface as the CHF$_3$ and SF$_{6}$ treatment pressure increases. The corrosion could be suppressed successfully with CHF$_3$ and SF6 treatment in the pressure of 300mTorr.orr.

• 한국물환경학회지
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• 제23권3호
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• pp.371-376
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• 2007

The features of precipitating reaction of fluorine have been examined under several aquatic conditions by employing calcium ion as a precipitant. Based on MINTEQ program, fluorine was found to exist in the forms of $H_2F_2$ and HF in strong acidic environment and change into $F^-$ with increasing pH. In the experimental condition, the precipitating reaction of fluorine progressed rapidly within a few minutes after the reaction started and reached its equilibrium in 10 minutes. As the addition of precipitant was increased, removal of fluorine by the formation of precipitate was promoted and its was also enhanced by the rise of pH. The precipitating reaction of fluorine was impeded when its initial concentration was low and X-ray analysis showed that the crystalline structure of precipitate was mainly $CaF_2$ with partly NaF. Coexisting phosphate in solution influenced the fluorine removal by impeding the precipitate formation and similar effect was found when metallic ion such as $Zn^{2+}$ was present with fluorine.

• ETRI Journal
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• 제21권3호
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• pp.16-21
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• 1999

After etching Al-Cu alloy films using SiCl4/Cl_2/He/CHF3 mixed gas plasma, the corrosion phenomenon at the grain boundary of the etched surface and a passivation layer on the etched surface with an SF6 plasma treatment subsequent to the etching were studied. In Al-Cu alloy system, corrosion occurs rapidly on the etched surface by residual chlorine atoms, and it occurs dominantly at the grain boundaries rather than the crystalline surfaces. To prevent corrosion, the SF6 gas plasma treatment subsequent to etching was carried out. The passivation layer is composed of fluorine-related compounds on the etched Al-Cu surface after the SF6 treatment, and it suppresses effectively corrosion on the surface as the SF6 treatment pressure increases. Corrosion could be suppressed successfully with the SF6 treatment at a total pressure of 300 mTorr. To investigate the reason why corrosion could be suppressed with the SF6 treatment, behaviors of chlorine and fluorine were studied by various analysis techniques. It was also found that the residual chlorine incorporated at the grain boundary of the etched surface accelerated corrosion and could not be removed after the SF6 plasma treatment.

• 한국진공학회지
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• 제5권4호
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• pp.327-332
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• 1996

Tungsten(W) polycide gate 구조에서 $WSi_x$의 두께가 증가하면 열처리 공정 후 Gate oxide의 두께가 증가하며, 전기적 신뢰도가 열화 되는 현상이 발생한다. 이러한 특성 열화를 일으키는 지배적인 요인은 $WSi_x$ 증착 공정 중 유입되어 후속 열 공정에 의하여 gate oxide로 환산되는 fluorine인 것으로 밝혀졌다. 이러한 현상을 규명하기 위하여 fluorine ion implantation된 poly Si과의 특성을 비교하였으며, SIMS 및 단면 TEM을 이용한 미세 구조 연구를 실시하였다. 그러나 $WSi_x$의 두께가 600$\AA$ 이상부터는이러한 특성 열화가 포화되는 현상이 관찰되었다. 600$\AA$ 이상의 $WSi_x$ 두께에서는 미세 구조가 표면이 거칠고, porous한 phase로 구성된 상부 구조와 비교적 dense하고, 매끈한 계면 상태를 갖는 하부 구조로 이루어졌으며, porous한 표면 부위는 후속 열공정 중 oxygen-rich한 phase로 변하여 fluorine을 포획하여 oxide로의 확산을 억제하여 특성 열화가 포화되는 것으로 해석되었다.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2015년도 제49회 하계 정기학술대회 초록집
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• pp.62-62
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• 2015

In this study, we study the effects of CF4 plasma treatment on the characteristics of enhancement mode (E-mode) AlGaN/GaN high electron mobility transistors (HEMTs). The CF4 plasma is generated by inductively coupled plasma reactive ion etching (ICP-RIE) system. The CF4 gas is decomposed into fluorine ions by ICP-RIE and then fluorine ions will effect the AlGaN/GaN interface to inhibit the electron transport of two dimension electron gas (2DEG) and increase channel resistance. The CF4 plasma method neither like the recessed type which have to utilize Cl2/BCl3 to etch semiconductor layer nor ion implantation needed high power to implant ions into semiconductor. Both of techniques will cause semiconductor damage. In the experiment, the CF4 treatment time are 0, 50, 100, 150, 200 and 250 seconds. It was found that the devices treated 100 seconds showed best electric performance. In order to prove fluorine ions existing and CF4 plasma treatment not etch epitaxial layer, the secondary ion mass spectrometer confirmed fluorine ions truly existing in the sample which treatment time 100 seconds. Moreover, transmission electron microscopy showed that the sample treated time 100 seconds did not have etch phenomena. Atomic layer deposition is used to grow Al2O3 with thickness 10, 20, 30 and 40 nm. In electrical measurement, the device that deposited 20-nm-thickness Al2O3 showed excellent current ability, the forward saturation current of 210 mA/mm, transconductance (gm) of 44.1 mS/mm and threshold voltage of 2.28 V, ION/IOFF reach to 108. As IV concerning the breakdown voltage measurement, all kinds of samples can reach to 1450 V.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2004년도 춘계학술대회 논문집 반도체 재료 센서 박막재료 전자세라믹스
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• pp.26-29
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• 2004

High density plasma fluorinated silicate glass (HDP FSG) is used as a gap fill film for metal-to-metal space because of many advantages. However, FSG films can cause critical problems such as bonding issue of top metal at package, metal contamination, metal peel-off, and so on. It is known that these problems are caused by fluorine penetration out of FSG film. To prevent it, FSG capping layers such like SRO (Silicon Rich Oxide) are needed. In this study, their characteristics and a capability to block fluorine penetration for various FSG capping layers are investigated. Normal stress and High stress due to denser film. While heat treatment to PETEOS caused lower blocking against fluorine penetration, it had insignificant effect on SiN. Compared with other layers, SRO using ARC chamber and SiN were shown a better performance to block fluorine penetration.

• 한국표면공학회지
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• 제34권3호
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• pp.258-263
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• 2001

Siloxane thin films were fabricated on a silicon wafer by spin-coating using a siloxane solution made by the sol-gel process. Fluorine was doped using$ CF_4$ plasma treatment. The film was then annealed in-situ state in the nitrogen atmosphere. In order to examine the influence of annealing and fluorine doping on the siloxane thin film, thermogravimetric-differential thermal analysis (TG-DTA), Fourier transform-infrared spectroscopy (FT-IR) and X-ray photoelectron spectroscopy (XPS) were used and the dielectric constant was determined by the high-frequency capacitance-voltage method. Stable siloxane films could be obtained by in-situ annealing in a nitrogen atmosphere after $CF_4$ plasma treatment, and the dielectric value of the film was $\varepsilon$ 2.5.