• Journal of the Korean Vacuum Society
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• v.6 no.3
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• pp.267-274
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• 1997

Silicon shallow trenches applied to the STI (Shallow Trench Isolation) of integrated circuits were etched using inductively coupled $Cl_2$ and HBr/$Cl_2$ plasmas and the effects of process parameters on the etch profiles of silicon trenches and the physical damages on the trench sidewall and bottom were investigated. The increase of inductive power and bias voltage in $Cl_2$ and HBr/$Cl_2$ plasmas increased polysilicon etch rates in general, but reduced the etch selectivities over nitride. In case of $Cl_2$ plasma, low inductive power and high bias voltage showed an anisotropic trench etch profile, and also the addition of oxygen or nitrogen to chlorine increased the etch anisotropy. The use of pure HBr showed a positively angled etch profile and the addition of $Cl_2$ to HBr improved the etch profile more anisotropically. HRTEM study showed physical defects formed on the silicon trench surfaces etched in $Cl_2/N_2$ or HBr/ $Cl_2$ plasmas.

• Transactions on Electrical and Electronic Materials
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• v.10 no.1
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• pp.1-4
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• 2009

Dry etching characteristics of indium tin oxide films and etch selectivities over photoresist films were investigated using $Cl_2/HBr$ inductively coupled plasma. From a Langmuir probe diagnostic system, it was observed that while the plasma temperature was kept nearly constant in spite of the change of the HBr mixing ratio, the positive ion density decreases rapidly with increasing the mixing ratio. On the other hand, a quadrupole mass spectrometer showed that the neutral HBr and Br species increased. The etching mechanism in the $HBr/Cl_2$ plasma was analyzed.

• Proceedings of the KIEE Conference
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• 1998.07d
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• pp.1294-1296
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• 1998

Platinum thin films which hardly form volatile compounds with any reactive gas at normal process temperature was etched in Inductively Coupled Plasma (ICP) using Ar/HBr/$Cl_2$ gases. It is observed that the etch rate of platinum is reduced as increasing of HBr/$Cl_2$ gas mixing ratio when Ar gas ratio is fixed. However, we obtain good etching profile of platinum films without unwanted residues in 90% Ar/5% HBr/5% $Cl_2$ gas mixing ratio.

• Journal of the Korean Vacuum Society
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• v.7 no.2
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• pp.155-160
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• 1998

It is necessary to use Arc layer and DUV resist to define 0.25 $\mu \textrm{m}$ line and space for 256 MDRAM devices. Poly-Si etching with Arc layer and different resists has been performed in a TCP-9408 etcher with variation of gas chemistries; $Cl_2/O_2, Cl_2/N_2, Cl_2$/HBr . DUV resist causes more positive etch profile and CD gain compared to I-line resist because the sidewall passivation is more stimulated by increasing polymerization through the loss of resist. When Arc layer is applied, CD hain also increases due to the polymeric mask formed after thching Arc layer. From the point of gas chemistry effects, the etch profile and CD gain is not improved using $Cl_2/O_2$ gas, since polymerization is accelerated in this gas. however, the vertical profile and less CD gain is obtained using $Cl_2$/HBr gas. Furthermore, HBr gas is very effective to suppress the difference of profile and CD variation between dense pattern and isolated pattern by minimizing non-uniformity of side wall passivation with pattern density.

• Analytical Science and Technology
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• v.19 no.2
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• pp.131-141
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• 2006

Hydrobromic acid salt of a $N_2O_2$ tetradentate ligand, N,N'-bis(2-hydroxybenzyl)-ethylene-diamine ($H-BHE{\cdot}2HBr$) was synthesized. $Br-BHE{\cdot}2HBr$, $Cl-BHE{\cdot}2HBr$, $CH_3-BHE{\cdot}2HBr$ and $CH_3O-BHE{\cdot}2HBr$ having Br, Cl, $CH_3$ and $CH_3O$ substituents at 5-position of the phenol group of $H-BHE{\cdot}2HBr$ were also synthesized. $Nap-BHE{\cdot}2HBr$ having naphthalen-2-ol instead of the phenol group was also synthesized. The potentiometry study in aqueous solution revealed that the proton dissociations of the synthesized ligands occurred in four steps and the order of the calculated overall proton dissociation constants (${\log}{\beta}_p$) of each ligand was Br-BHE < Cl-BHE < H-BHE < Nap-BHE < $CH_3$-BHE < $CH_3O$-BHE. The order showed a similar trend to that of Hammett substituent constants(${\sigma}_P$). The order of the stability constants (${\log}K_{ML}$) was CO(II) < Ni(II) < Cu(II) > Zn(II) > Cd(II) > Pb(II). The order in their stability constants (${\log}K_{ML}$) of each transition metal complex agreed well with that of the overall proton dissociation constants (${\log}{\beta}_p$).

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 1998.05a
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• pp.39-40
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• 1998

• Korean Chemical Engineering Research
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• v.47 no.1
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• pp.79-83
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• 2009

In this study, the characteristics of amorphous silicon etching for the formation of gate electrodes have been evaluated at the variation of several process parameters. When total flow rates composed of $Cl_2/HBr/O_2$ gas mixtures increased, the etch rate of amorphous silicon layer increased, but critical dimension (CD) bias was not notably changed regardless of total flow rate. As the amount of HBr in the mixture gas became larger, amorphous silicon etch rate was reduced by the low reactivity of Br species. In the case of increasing oxygen flow rate, etch selectivity was increased due to the reduction of oxide etch rate, enhancing the stability of silicon gate etching process. However, gate electrodes became more sloped according to the increase of oxygen flow rate. Higher source power induced the increase of amorphous silicon etch rate and CD bias, and higher bias power had a tendency to increase the etch rate of amorphous silicon and oxide.

• 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.

• Journal of Environmental Science International
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• v.15 no.8
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• pp.799-809
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• 2006

Hydrobromic acid salts of new N, N, O tridentate ligands containing phenol, 2-[(2-Methylamino- ethyl- amino)-methyl]-phenol(H-MMP. 2HBr), 5-Bromo-2-[(2-Methylamino-ethylamino)-methyl]-phenol (Br- MMP. 2HBr), 5-Chloro-2-[(2-Methylamino-ethylamino)-methyl]-phenol(Cl-MMP. 2HBr), 5-Methyl-2-[(2-Methylamino-ethylamino)-methyl]-phenol(Me-MMP. 2HBr), 5-Methoxy-2-I(2-Methylamino-ethylamino)- methyl]-phenol(MeO- MMP. 2HBr) and. 1-[(2-Methylamino-ethylamino)- methyl]-naphthalen-2-ol(Nap- MMP. 2HBr) were synthesized. The synthesized ligands were confirmed by C. H. N. atomic analysis, UV-visible and IR spectroscopies, $^1$H NMR, $^{13}$C NMR and mass analysis. The potentiometry study revealed that the proton dissociation constants(logK$_n^H$) of the synthesized ligands and stability constants (logK$_{ML}$, logK$_{LM2}$) of transition metal complexes of Co(II), Ni(II), Cu(II), Zn(II), Cd(II) and Pb(II) ions occurred in three steps and the order of the calculated overall proton dissociation constants(log$\beta_p$) and stability constants (logK$_{ML}$) of ligands was Br-MMP. 2HBr < Cl-MMP 2HBr < H-MMP. 2HBr < Nap-MMP. 2HBr < Me-MMP. 2HBr < MeO-MMP. 2HBr. The order showed a similar trend to that of Hammett substituent constants($\delta_p$). The synthesized ligands usually form 2:1(ML$_2$) complexes with transition metal ions. The order of the stability constants of each transition metal ions was Co(II) < Ni(II) < Cu(II) ;> Zn(II) ;> Cd(II) ;> Pb(II).

• Journal of the Korean Chemical Society
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• v.53 no.2
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• pp.133-136
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• 2009

We present calculations for the 4-aminopyrimidine (4AP) – HCl and –HBr complexes. We predict that the charge separated (zwitterionic) form [4AP$H^+-Cl^-$] is not stable, but that [4AP$H^+-Br^-$] is stable enough for experimental detection in gas phase at low temperatures. The latter observation is attributed to smaller dissociation energy of HBr compared with HCl, and to “solvation” of HBr by the amino group in 4AP.