• Korean Chemical Engineering Research
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• v.44 no.5
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• pp.483-488
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• 2006

Etching process of PMMA (Polymethyl Methacrylate) on glass surface was investigated by dry etching technique using remote plasma. To determine the etching characteristics, the remote plasma etching was conducted for various process parameters such as plasma power, reaction gas and distance from plasma generation. As the distance from the plasma generation was increased, the etch rate of PMMA was linearly decreased by radical density in plasma. PMMA has removed by reactive radicals in the plasma. The etch rate increased with plasma power because of more reactive radicals. The etch rate and surface roughness of PMMA increased with $O_2$ concentration in the etchant.

• Transactions on Electrical and Electronic Materials
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• v.12 no.3
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• pp.106-109
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• 2011

We investigated the etching characteristics of titanium nitride (TiN) thin film in $BCl_3$/Ar inductively coupled plasma. The etching parameters were the gas mixing ratio, radio frequency (RF) power, direct current (DC)-bias voltages and process pressures. The standard conditions were as follows: total flow rate = 20 sccm, RF power = 500 W, DC-bias voltage = -100 V, substrate temperature = $40^{\circ}C$, and process pressure = 15 mTorr. The maximum etch rate of TiN thin film and the selectivity of TiN to $Al_2O_3$ thin film were 54 nm/min and 0.79. The results of X-ray photoelectron spectroscopy showed no accumulation of etch byproducts from the etched surface of TiN thin film. The TiN film etch was dominated by the chemical etching with assistance by Ar sputtering in reactive ion etching mechanism, based on the experimental results.

• Journal of Information Display
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• v.2 no.4
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• pp.1-7
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• 2001

This paper investigates the characteristics of a newly developed high density hollow cathode plasma(HCP) system and its application for the etching of silicon wafers. We used $SF_6$ and $O_2$ gases in the HCP dry etch process. This paper demonstrates very high plasma density of $2{\times}10^{12}cm^{-3}$ at a discharge current of 20 rna, Silicon etch rate of 1.3 ${\mu}m$/min was achieved with $SF_6/O_2$ plasma conditions of total gas pressure of 50 mTorr, gas flow rate of 40 seem, and RF power of200W. This paper presents surface etching characteristics on a crystalline silicon wafer and large area cast type multicrystlline silicon wafer. We obtained field emitter tips size of less than 0.1 ${\mu}m$ without any photomask step as well as with a conventional photolithography. Our experimental results can be applied to various display systems such as thin film growth and etching for TFT-LCDs, emitter tip formations for FEDs, and bright plasma discharge for PDP applications. In this research, we studied silicon etching properties by using the hollow cathode plasma system.

• Clean Technology
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• v.18 no.3
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• pp.280-286
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• 2012

The dry etching of sacrificial $SiO_2$ was performed in supercritical carbon dioxide. The etching of boron phosphor silica glass (BPSG), tetraethyl orthosilicate (TEOS), thermal $SiO_2$, and Si-nitride (SiN) was investigated by using a two chamber system with HF/py etchant and alcohol additives. The etch rate of sacrificial $SiO_2$ increased upon the addition of methanol. The etch selectivity of BPSG with respect to SiN was highest with IPA although the highest etch rate was resulted from methanol except BPSG. The etch rate increased with the temperature in HF/py/MeOH system. Especially the increase of the etch rate was much higher for BPSG with an increase in the reaction temperature. The etch residue was not reduced apparently upon the addition of alcohol cosolvents to HF/py. While the etch rate in HF/$H_2O$ was higher than HF/py/alcohol system, the rate decreased with the addition of alcohols to HF/$H_2O$. The cantilever beam structure of high aspect ratios was released by the dry ething in supercritical carbon dioxide without damage.

• Korean Chemical Engineering Research
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• v.43 no.1
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• pp.76-79
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• 2005

Dry etching of NiFe, NiFeCo, and Ta for magnetic random access memory (MRAM) by inductively coupled plasmas (ICPs) of $Cl_2/Ar$ has been carried out. NiFe and NiFeCo showed maximum etch rates at a particular ICP source power, but the etch rate of Ta increased with the ICP source power. The etch rates of the magnetic thin films increased with the RF chuck power, but decreased with the operating pressure and the $Cl_2$ concentration. To avoid a corrosion problem by chlorine, the etched samples were rinsed with de-ionized water for 5 minutes after etching. The etch profile showed a clean and smooth surface at 50% $Cl_2$ concentration.

• Restorative Dentistry and Endodontics
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• v.27 no.4
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• pp.363-369
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• 2002

최근에 많이 사용되어지고 있는 치과용 접착제는 산 부식 후 수분이 있는 상태에서 적용하는 wet-bonding 술식을 많이 추천하고 있다. 하지만 self-etching primer의 경우 산부식과 priming 과정이 동시에 시행되고, 제조자들은 건조된 치아표면에 적용할 것을 추천하고 있다. 그러나 건조된 정도에 대하여서는 별다른 추천사항이 없으며. 수분이 self-etching primer에 어떤 영향을 미치는지에 대하여서는 별다른 연구가 이루어져 있지 않은 상태이다. 이에 본 연구에서는 치질 삭제 후 남아있는 수분이 self-etching primer의 레진 접착 강도에 어떤 영향을 미치는 지를 알아보고자 하였다. 발거한 대구치 96개를 이용하여 물기가 있는 상태에서 #600 사포로 표면을 연마하고, 법랑질 면을 노출시킨 군과 상아질을 노출시킨 군으로 분류 후, 30분 공기 중 방치 군 (1군), 5초 공기 건조 군 (2군), 1초 공기 건조 군 (3군), 솜으로 약간의 물기를 제거한 군(blot dry) (4군) 등 총 8개의 군으로 나누었다. Self-etching adhesive system인 Clearfil SE Bond primer를 20초간 적용하고, bonding제 도포 후 10초간 광중합 시행하였다. 접착제 처리한 치아면에 몰드를 고정한 후 Clearfil AP-X 복합레진을 2mm 충전하고, 40초간 광중합을 시행하였다. 24시간 후 전단 응력 결합강도를 측정하였으며, 그 결과는 다음과 같이 나타났다. 법랑질과 상아질 모두에서, 30분 건조군과 5초 공기건조군이 1초와 blot drying 군보다 높은 결합강도를 보였으며 통계학적으로 유의한 차이를 보였다(p＜0.05). 본 실험 결과에 의하면 self-etching adhesive system을 사용함에 있어서 법랑질과 상아질군 공히 건조된 상태에서 사용하여야 하며 수분의 존재시 치아와의 결합력이 감소하는 것으로 나타났다. 따라서 임상에서 접착제의 적용시 수분의 조절에 주의하여야 할 것으로 사료된다.

• Transactions on Electrical and Electronic Materials
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• v.1 no.3
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• pp.14-17
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• 2000

Giga bit dynamic random access memory(DRAM) requires the capacitor of high dielectric films. Some metal oxides films have been proposed as the dielectric material . And Pt is one of the most promising electrode materials. However very little has been done in developing the etching technologoy Pt film. Therefore, it is the first priority to develop the technology for plasma etching of Pt film. In this study, the dry etching of Pt film was investigated in Inductively Coupled Plasma(ICP) etching system with Cl$_2$/Ar and HBr/Cl$_2$/Ar gas mixing. X-ray photoelectron spectroscopy (XPS) was used in analysis of sidewall residues for the understanding of etching mechanism. We found the etch residues on the pattern sidewall is mainly Pt-Pt, Pt-Cl and Pt-Br compounds, Etch profile was observed by Scanning Electron Spectroscopy(SEM) . The etch rate of Pt film at 10%, Cl$_2$/90% Ar gas mixing ration was higher than at 100%. Ar. Addition of HBr to Cl$_2$/Ar as an etching gas led to generally higher selectivity to SiO$_2$. And the etch residues were reduced at 5% HBr/5% Cl$_2$/90% Ar gas mixing ration. These pages provide you with an examples of the layout and style which we wish you to adopt during the preparation of your paper, Make the width of abstract to be 14cm.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2008.11a
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• pp.145-145
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• 2008

High-k materials have been paid much more attention for their characteristics with high permittivity to reduce the leakage current through the scaled gate oxide. Among the high-k materials, $ZrO_2$ is one of the most attractive ones combing such favorable properties as a high dielectric constant (k= 20 ~ 25), wide band gap (5 ~ 7 eV) as well as a close thermal expansion coefficient with Si that results in good thermal stability of the $ZrO_2$/Si structure. During the etching process, plasma etching has been widely used to define fine-line patterns, selectively remove materials over topography, planarize surfaces, and trip photoresist. About the high-k materials etching, the relation between the etch characteristics of high-k dielectric materials and plasma properties is required to be studied more to match standard processing procedure with low damaged removal process. Among several etching techniques, we chose the inductively coupled plasma (ICP) for high-density plasma, easy control of ion energy and flux, low ownership and simple structure. And the $BCl_3$ was included in the gas due to the effective extraction of oxygen in the form of $BCl_xO_y$ compounds. During the etching process, the wafer surface temperature is an important parameter, until now, there is less study on temperature parameter. In this study, the etch mechanism of $ZrO_2$ thin film was investigated in function of $Cl_2$ addition to $BCl_3$/Ar gas mixture ratio, RF power and DC-bias power based on substrate temperature increased from $10^{\circ}C$ to $80^{\circ}C$. The variations of relative volume densities for the particles were measured with optical emission spectroscopy (OES). The surface imagination was measured by scanning emission spectroscope (SEM). The chemical state of film was investigated using energy dispersive X-ray (EDX).

• Journal of the Korean Vacuum Society
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• v.10 no.4
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• pp.411-415
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• 2001

Using the plasma that we developed to generate a low-temperature plasma at atmospheric pressure, we have investigated the etching possibility of tin oxide $(SnO_2)$ thin films. Hydrogen and methane radicals generated from the plasma were observed and their intensity was found to be dependent on the cathode material by an analysis with optical emission spectroscopy as well as by the plasma impedance. The etching ability of this plasma was evaluated by an emission intensity as well as by the evaluation of impedance using a plasma I-V curve.

• Transactions on Electrical and Electronic Materials
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• v.15 no.4
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• pp.221-225
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• 2014

Although gold wire bonding techniques have already matured in semiconductor manufacturing, weakly bonded wires in semiconductor chip assembly can jeopardize the reliability of the final product. In this paper, weakly bonded or failed aluminum bonding pads are analyzed using X-ray photoelectron spectroscopy (XPS), Auger electron Spectroscopy (AES), and energy dispersive X-ray analysis (EDX) to investigate potential contaminants on the bond pad. We found the source of contaminants is related to the dry etching process in the previous manufacturing step, and fluorocarbon plasma etching of a passivation layer showed meaningful evidence of the formation of fluorinated by-products of $AlF_x$ on the bond pads. Surface analysis of the contaminated aluminum layer revealed the presence of fluorinated compounds $AlOF_x$, $Al(OF)_x$, $Al(OH)_x$, and $CF_x$.