• 한국전기전자재료학회논문지
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• 제13권8호
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• pp.651-657
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• 2000

The notching effect in etching of undoped amorphous silicon gate had different characteristics and mechanism comparing with reported ones. The undoped amorphous silicon was etched by using HBr gas plasma. First in the region of small line width the potential increased as a result of ions in the exposed surface of oxide and the incident ions between the small line widths were deflected more wide range therefore the depth of notching was shallow and wide. Second in the region of large line width of gate electrons were charged on the top of photoresist and the side of gate a part of ions deflected. The deflected ions were partly charged positive on the side of gate and then these partly charged ions produced potential difference. Therefore ions stored up more at independent line than at dense line and notching became deeper by Br ion bombardments.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2000년도 춘계학술대회 논문집 전자세라믹스 센서 및 박막재료 반도체재료 일렉트렛트 및 응용기술
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• pp.10-13
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• 2000

The notching effect in etching of un doped amorphous silicon gate had different characteristics and mechanism comparing with reported ones. The undoped amorphous silicon was etched by using HBr gas plasma, First, in the region of small line width, the potential was increased as a result of ions in the exposed surface of oxide, and the incident ions between the small line width were deflected more wide range, therefore the depth of notching was shallow and wide, Second, in the region of large line width of gate, electrons were charged on the top of photoresist and the side of gate, a part of ions deflected, The deflected ions were locally charged positive on the side of gate, and then the potential difference was produced, therefore, ions stored up more at independent line than at dense line, and nothing became deeper by Br ion bombardment.

• 한국세라믹학회지
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• 제40권9호
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• pp.886-890
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• 2003

단결정 LiNbO$_3$를 helicon wave plasma 방법으로 식각시 bias power와 CF$_4$, HBr, SR$_{6}$가 혼합된 gas 유량에 따른 식각 속도와 rms roughness 값의 특성을 관찰하였다. 식각된 깊이는 surface profiler로 관찰하였으며 rms roughness 값은 Atomic Force Microscopy (AFM)으로 측정하였다. Bias power 증가함에 따라 500W에서 가장 높은 식각 속도와 가장 평탄한 표면형상을 얻을 수 있었으며, CF$_4$, HBr, SF$_{6}$ gas 유량을 각각 10～30 sccm으로 증가시킴에 따라 식각 속도는 CF$_4$, HBr, SF$_{6}$ gas 유량이 10 sccm, 30 sccm, 10 sccm에서 가장 높게 나타났으며, rms roughness 값은 CF$_4$, HBr, SF$_{6}$ gas 유량이 30 sccm, 10 sccm, 30 sccm에서 가장 낮은 표면 조도를 나타내었다.

• 한국전기전자재료학회논문지
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• 제17권1호
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• pp.1-6
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• 2004

Dry etch characteristics of polysilicon with HBr/O$_2$ inductively coupled plasma (ICP) have been investigated. We determined etch late, uniformity, etch profiles, and selectivity with analyzing the cross-sectional scanning electron microscopy images obtained from top, center, bottom, right, and left positions. The etch rate of polysilicon was about 2500 $\AA$/min, which meets with the mass production for devices. The wafer level etch uniformity was within $\pm$5 ％. Etch profile showed 90$^{\circ}$ slopes without notches. The selectivity over photoresist was between 2:1∼4.5:1, depending on $O_2$ flow rate. The HBr-ICP etching showed higher PR selectivity, and sharper profile than the conventional Cl$_2$-RIE.

• 한국진공학회지
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• 제7권3호
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• pp.169-175
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• 1998

HBr/$Cl_2/He-O_2$ 반응 기체를 이용한 반응성 이온 식각후, 폴리실리콘 표면에 형성된 잔류막을 x-선 광전자 분광법(x-ray photoelectron spectroscopy, XPS)과 전자 현미경 (scanning electron mocroscopy, SEM)을 이용하여 관찰하였다. 그 결과 잔류물은 패턴된 폴 리실리콘의 맨 윗부분에 자존하고 있었으며, 화학 결합 상태는 실리콘 산화물임이 밝혀졌다. 잔류물인 실리콘 산화물의 형성 메카니즘을 규명하기 위하여 원래의 혼합 기체 성분중 한가 지씩의 반응 기체를 제외시켜 가면서 실험하였다. 비록 플라즈마 성질이 다를지라도, 잔류물 은 산소의 존재하에서 잘 형성됨을 알 수 있었는데, 이는 휘발성이 낮은 실리콘-할로겐 화 합물이 산소에 의해 산화됨으로써 형성되는 것으로 이해하게 되었다. 또한 반응성 이온 식 각후 형성된 잔류층은 소자의 전기적 특성과 후처리 공정에 영향을 미치는 것으로 알려져 있어서, 이를 제거하기 위해 습식과 건식 후처리 공정을 도입하여 비교하였다. 그 결과 건식 공정의 경우 기체에 의해 새로운 잔류물이 형성됨을 XPS를 통하여 관찰하였다. 따라서 잔 류물을 제거하고 깨끗한 표면을 얻기 위해서는 습식 공정이 더 적합함을 알았다.

• 한국진공학회:학술대회논문집
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• 한국진공학회 1997년도 제12회 학술발표회 논문개요집
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• pp.227-228
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• 1997

• 한국진공학회:학술대회논문집
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• 한국진공학회 1997년도 제12회 학술발표회 논문개요집
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• pp.230-230
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• 1997

• 한국응용과학기술학회지
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• 제16권1호
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• pp.105-115
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• 1999

P-type의 단결정 실리콘 위에 $1000{\AA}$의 열산화막을 성장시킨후 $5500{\AA}$의 다결정 실리콘으로 증착된 시료를 가지고 $HBr/Cl_2/He-O_2$ 혼합기체로 식각할 때 시료의 식각 특성에 관한 $H_2-O_2$ 기체함량. RF 전력, 압력에 대한 영향을 XPS(X-ray photoelectron Spectroscopy)와 SEM(Scanning Electron Microscopy)으로 조사하였다. $HBr/Cl_2/He-O_2$ 혼합기체로 식각되는 동안 형성된 다결정 실리콘 식각속도는 $H_2-O_2$ 함량 증가에 따라 증가하였으며 식각잔유물은 RF 전력과 압력변화에 의해 영향은 받지 않는 것으로 나타났으며, 다결정 실리콘 측벽에서의 증착속도는 낮은 RF전력과 높은 압력에서 높게 나타났다. 다결정 실리콘 식각 잔유물의 결합에너지는 안정한 $SiO_2$인 열산화막의 경우보다 높으므로 식각 잔유물은 $SiO_{\chi}({\chi}>2)$의 화합결합을 가지는 산화물과 같은 잔유물로 생각된다.

• 한국표면공학회지
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• 제32권2호
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• pp.83-92
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• 1999

GaN etching was performed using planar inductively coupled $Cl_2$-based plasmas and the effects of main process parameters on the characteristics of the plasmas and their relations to GaN etch rates were studied. Also, the GaN etch mechanism was investigated using a Langmuir probe and optical emission spectroscopy (OES) during the etching, and X-ray photoelectron spectroscopy (XPS) of the etched surfaces. The GaN etch rates increased with the increase of chlorine radical density and ion energy, and a vertical etch profile haying the etch rate close to 4000 $\AA$/min could be obtained. The addition of 10% Ar to $Cl_2$ gas increased the GaN etch rate and the addition of Ar (more than 20%) and HBr generally reduced the GaN etch rate. The GaN etch rate appeared to be more affected by the chemical reaction between Cl radicals and GaN compared to the physical sputtering itself under the sufficient ion bombardments to break GaN bonds.

• Bulletin of the Korean Chemical Society
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• 제30권8호
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• pp.1832-1834
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• 2009

A simple and safe method has been presented for conversion of olefins into bromohydrins using hydrogen bromide and hydrogen peroxide as bromide source by visible light induced within a very short time to get high yield bromohydrins along with a little mount dibromo-product. In this paper, cyclohexene is firstly carried out as the model substrate and investigated the bromination under HBr/$H_2O_2$ system using 150 W incandescent light irradiated in C$Cl_4$ within short time to get good yield of 2-bromocyclohexanol along with a little mount of 1,2-dibromocyclohexane; then, a series of alkenes are brominated to corresponding bromohydrins using the same protocol.