• Proceedings of the Korean Society of Precision Engineering Conference
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• 2012.05a
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• pp.503-504
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• 2012

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2011.06a
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• pp.641-642
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• 2011

• Proceedings of the Korean Vacuum Society Conference
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• 1999.07a
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• pp.65-65
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• 1999

Dry etching technique provides more easy controllability on the etch profile such as anisotropic etching than wet etching process and the results of lots of researches on the characterization of various plasmas or ion beams for semiconductor etching have been reported. Chlorine-based plasmas or chlorine ion beam have been often used to etch several semiconductor materials, in particular Si-based materials. We have studied the effect of He flow rate on the Si and SiO2 dry etching using chlorine-based plasma. Experiments were performed using reactive ion etching system. RF power was 300W. Cl2 gas flow rate was fixed at 58.6 sccm, and the He flow rate was varied from 0 to 120 sccm. Fig. 1 presents the etch depth of si layer versus the etching time at various He flow rate. In case of low He flow rate, the etch rate was measured to be negligible for both Si and SiO2. As the He flow increases over 30% of the total inlet gas flow, the plasma state becomes stable and the etch rate starts to increase. In high Ge flow rate (over 60%), the relation between the etch depth and the time was observed to be nearly linear. Fig. 2 presents the variation of the etch rate depending on the He flow rate. The etch rate increases linearly with He flow rate. The results of this preliminary study show that Cl2/He mixture plasma is good candidate for the controllable si dry etching.

• 한국정보디스플레이학회:학술대회논문집
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• 2007.08a
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• pp.922-925
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• 2007

In the usual dry etching process for the TFT-LCD fabrication, it is hard to monitor the basic plasma parameters such as density and temperature. However, the basic parameters are easily monitored during the dry etching process. We have simultaneously measured the electric characteristics and basic plasma parameters of the dry etching chamber during the process, analyzed them to interpret plasma parameters. For the Ar plasma discharge case, we could obtain the density and temperature from the electric characteristics using a simple simple sheath model.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.22 no.12
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• pp.1005-1008
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• 2009

In this study, adaptively coupled plasma (ACP) source was used for dry etching of $Al_2O_3$ thin film. During the etching process, the wafer surface temperature is an important parameter to influent the etching characteristics. Therefore, the experiments were carried out in ACP to measuring the etch rate, the selectivities of $Al_2O_3$ thin film to mask materials and the etch profile as functions of $Cl_2$/Ar gas ratio and substrate temperature. The highest etch rate of $Al_2O_3$ was 65.4 nm/min at 75% of $Cl_2/(Cl_2+Ar)$ gas mixing ratio. The etched profile was characterized using field effect scanning electron microscopy (FE-SEM). The chemical states of $Al_2O_3$ thin film surfaces were investigated with x-ray photoelectron spectroscopy (XPS).

• Proceedings of the KACD Conference
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• 2001.11a
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• pp.587.2-587
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• 2001

The purpose of this study is to evaluate influence of moisture control on bond strength of self-etching primer by measuring enamel and dentin shear bond strengths. 96 extracted human molars were divided into 8 groups. Group 1 (Enamel 30min Dry), Group 2 (E. 5s air dry), Group 3 (E. 1s air dry), Group 4 (E. blot dry), Group 5 (Dentin 30min Dry), Group 6 (D. 5s air dry), Group 7 (D. 1s air dry), Group 8 (D. blot dry) were divided.(omitted)

• Journal of the Korean institute of surface engineering
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• v.49 no.1
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• pp.98-103
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• 2016

The dry etching characteristics of SnO thin films were investigated using inductively coupled plasma (ICP) in Ar, $CF_4$, $Cl_2$ chemistries. the SnO thin films were deposited by reactive rf magnetron sputtering with Sn metal target. In order to study the etching rates of SnO, the processing factors of processing pressure, source power, bias power, and etching gas were controlled. The etching behavior of SnO films under various conditions was obtained and discussed by comparing to that of $SiO_2$ films. In our results, the etch rate of SnO film was obtained as 94nm/min. The etch rates were mainly affected by physical etching and the contribution of chemical etching to SnO films appeared relatively week.

• Journal of the Semiconductor & Display Technology
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• v.22 no.4
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• pp.26-31
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• 2023

We investigated the impact of NF₃ / H₂O remote plasma dry cleaning conditions on the SiO₂ etching rate at different preparation states during the fabrication of ultra-large-scale integration (ULSI) devices. This included consideration of factors like Si crystal orientation prior to oxidation and three-dimensional structures. The dry cleaning process were carried out varying the parameters of pressure, NF₃ flow rate, and H₂O flow rate. We found that the pressure had an effective role in controlling anisotropic etching when a thin SiO₂ layer was situated between Si₃N₄ and Si layers in a multilayer trench structure. Based on these observations, we would like to provide further guidelines for implementing the dry cleaning process in the fabrication of semiconductor devices having 3D structures.

• Proceedings of the KIEE Conference
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• 1997.11a
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• pp.276-278
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• 1997

The reliable etching process is one of the essential steps in fabricating GaN based-device. High etch rate is needed to obtain a deeply etched structure and perfect anisotropic etched facet is needed to obtain lasing profile. In the research, therefore, we had proposed a planar inductively coupled plasma etcher (Planar ICP Etcher) as a high density plasma source, and studied the etching mechanism using the $CH_4/H_2$/Ar gas mixture. Dry etching characteristics such as etch rate, anisotropic etching profile and so on, for the III-V nitride layers were investigated using Planar ICP Etcher, based on the plasma characteristic as a variation of plasma process parameters.

• Journal of information and communication convergence engineering
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• v.5 no.3
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• pp.215-218
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• 2007

In this paper, amorphous semiconductor and insulator thin film are etched using reactive ion etcher. At that time, we experiment in various RIE conditions (chamber pressure, gas flow rate, rf power, temperature) that have effects on quality of thin film. The using gases are $CF_4,\;CF_4+O_2,\;CCl_2F_2,\;CHF_3$ gases. The etching of a-Si:H thin film use $CF_4,\;CF_4+O_2$ gases and the etching of $a-SiO_2,\;a-SiN_x$ thin film use $CCl_2F_2,\;CHF_3$ gases. The $CCl_2F_2$ gas is particularly excellent because the selectivity of between a-Si:H thin film and $a-SiN_x$ thin film is 6:1. We made precise condition on dry etching with uniformity of 5%. If this dry etching condition is used, that process can acquire high yield and can cut down process cost.