• 한국재료학회:학술대회논문집
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• 한국재료학회 2007년도 춘계학술발표대회 및 제12회 신소재 심포지엄
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• pp.35.2-35.2
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• 2007

• 한국재료학회:학술대회논문집
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• 한국재료학회 2007년도 추계학술발표대회 및
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• pp.67.2-67.2
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• 2007

• 한국재료학회:학술대회논문집
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• 한국재료학회 2001년도 춘계학술발표강연 및 논문개요집
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• pp.119-119
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• 2001

• 한국재료학회:학술대회논문집
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• 한국재료학회 1996년도 재료학회 춘계학술발표회
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• pp.76-76
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• 1996

• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제48권9호
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• pp.616-621
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• 1999

A planar inductively coupled $CH_4/H_2/Ar$plasma was used to investigate dry etch characteristics of GaN as a function of input power, RF bias power, and etch gas composition. Etch rate of GaN increased with input power up to 600 W and was saturated at the higher power. Also, the etch rates increased with increasing RF bias power, composition of $CH_4$ and Ar gas. We achieved the maximum etch rate of $930{\AA}$/min at the input power 400 W, RF bias power 250 W, and operational pressure 10 mTorr. This paper shows that smooth etched surface having roughness less than 1 nm in rms can be obtained by using planar inductively coupled plasma with $CH_4/H_2/Ar$ gas chemistry.

• 전기전자학회논문지
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• 제13권4호
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• pp.23-27
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• 2009

실리콘 기판 상에 MBE (molecular beam epitaxy)로 형성된 GaSb 기반 p-channel HEMT 소자를 제작하기 위하여 오믹 접촉 형성 공정과 식각 공정을 연구하였다. 먼저 각 소자의 절연을 위한 메사 식각 공정 연구를 수행하였으며, HF기반의 습식 식각 공정과 ICP(inductively coupled plasma)를 이용한 건식 식각 공정이 모두 사용되었다. 이와 함께 소스/드레인 영역 형성을 위한 오믹 접촉 형성 공정에 관한 연구를 진행하였으며 Ge/Au/Ni/Au 금속층 및 $300^{\circ}C$ 60초 RTA공정을 통해 $0.683\;{\Omega}mm$의 접촉 저항을 얻을 수 있었다. 더불어 HEMT 소자의 게이트 형성을 위한 게이트 리세스 공정을 AZ300 현상액과 citric산 기반의 습식 식각을 이용하여 연구하였으며, citric산의 경우 소자 구조에서 캡으로 사용된 GaSb와 베리어로 사용된 AlGaSb사이에서 높은 식각 선택비를 보였다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2008년도 추계학술대회 논문집 Vol.21
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• pp.259-259
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• 2008

The LTCC (Low Temperature Co-fired Ceramic) technology meets the requirements for high quality microelectronic devices and microsystems application due to a very good electrical and mechanical properties, high reliability and stability as well as possibility of making integrated three dimensional microstructures. The wet process, which has been applied to the etching of the metallic thin film on the ceramic substrate, has multi process steps such as lithography and development and uses very toxic chemicals arising the environmental problems. The other side, Plasma technology like ion beam sputtering is clean process including surface cleaning and treatment, sputtering and etching of semiconductor devices, and environmental cleanup. In this study, metallic multilayer pattern was fabricated by the ion beam etching of Ti/Pd/Cu without the lithography. In the experiment, Alumina and LTCC were used as the substrate and Ti/Pd/Cu metallic multilayer was deposited by the DC-magnetron sputtering system. After the formation of Cu/Ni/Au multilayer pattern made by the photolithography and electroplating process, the Ti/Pd/Cu multilayer was dry-etched by using the low energy-high current ion-beam etching process. Because the electroplated Au layer was the masking barrier of the etching of Ti/Pd/Cu multilayer, the additional lithography was not necessary for the etching process. Xenon ion beam which having the high sputtering yield was irradiated and was used with various ion energy and current. The metallic pattern after the etching was optically examined and analyzed. The rate and phenomenon of the etching on each metallic layer were investigated with the diverse process condition such as ion-beam acceleration energy, current density, and etching time.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2005년도 하계학술대회 논문집 Vol.6
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• pp.164-165
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• 2005

The dry etch characteristics of GaAs over both AlGaAs and InGaP in planar inductively coupled $BCl_3$-based plasmas(ICP) with additions of $SF_6$ or $CF_4$ were studied. The additions of flourine gases provided enhanced etch selectivities of GaAs/AlGaAs and GaAs/InGaP. The etch stop reaction involving formation of involatile $AlF_3$ and $InF_3$ (boiling points of etch products: $AlF_3\sim1300^{\circ}C$, $InF_3$ > $1200^{\circ}C$ at atmosphere) were found to be effective under high density inductively coupled plasma condition. Decrease of etch rates of all materials was probably due to strong increase of flourine atoms in the discharge, which blocked the surface of the material against chlorine neutral adsorption. The process parameters were ICP source power (0 - 500 W), RF chuck power (0 - 30 W) and variable gas composition. The process results were characterized in terms of etch rate, selectivities of GaAs over AlGaAs and InGaP, surface morphology, surface roughness and residues after etching.

• 한국표면공학회지
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• 제34권5호
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• pp.516-521
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• 2001

Dry etching of Si wafer and $SiO_2$ layers was performed using He/Cl$_2$ mixture plasma by diode-type reactive ion etcher (RIE) system. For Si etching, the Cl molecules react with the Si molecules on the surface and become chemically stable, indicating that the reactants need energetic ion bombardment. During the ion assisted desorption, energetic ions would damage the photoresist (PR) and produce the bad etch Si-profile. Moreover, we have examined the characteristics of the Cl-Si reaction system, and developed the new fabrication procedures with a $Cl_2$/He mixture for Si and $SiO_2$-etching. The developed novel fabrication procedure allows the RIE to be unexpensive and useful a Si deep etching system. Since the etch rate was proved to increase linearly with fHe and the selectivity of Si to $SiO_2$ etch rate was observed to be inversely proportional to fHe.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2001년도 하계학술대회 논문집
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• pp.279-282
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• 2001

The IBE(ion beam etching)-induced Schottky barrier variation which depends on various etching history related with ion energy, incident angle and etching time has been investigated using voltage-current, capacitance-voltage characteristics of metal-etched silicon contact and morphology of etched surface were studied using AFM(atomic force microscope). For ion beam etched n-type silicons, Schottky barrier is reduced according to ion beam energy. It can be seen that amount of donor-like positive charge created in the damaged layer is proportional to the ion energy. By contrary, for ion beam etched p-type silicons, the Schottky barrier and specific contact resistance are both increased. Not only etching time but also incident angle of ion beam has an effect on barrier height. Taping-mode AFM analysis shows increased roughness RMS(Root-Mean-Square) and depth distribution due to ion bombardment. Annealing in an N$_2$ ambient for 30 min was found to be effective in improving the diode characteristics of the etched samples and minimum annealing temperatures to recover IBE-induced barrier variation were related to ion beam energy.