• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2008년도 추계학술대회 논문집 Vol.21
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• pp.363-363
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• 2008

The development of dry etching process for sapphire wafer with plasma has been key issues for the opto-electric devices. The challenges are increasing control and obtaining low plasma induced-damage because an unwanted scattering of radiation is caused by the spatial disorder of pattern and variation of surface roughness. The plasma-induced damages during plasma etching process can be classified as impurity contamination of residual etch products or bonding disruption in lattice due to charged particle bombardment. Therefor, fine pattern technology with low damaged etching process and high etch rate are urgently needed. Until now, there are a lot of reports on the etching of sapphire wafer with using $Cl_2$/Ar, $BCl_3$/Ar, HBr/Ar and so on [1]. However, the etch behavior of sapphire wafer have investigated with variation of only one parameter while other parameters are fixed. In this study, we investigated the effect of pressure and other parameters on the etch rate and the selectivity. We selected $BCl_3$ as an etch ant because $BCl_3$ plasmas are widely used in etching process of oxide materials. In plasma, the $BCl_3$ molecule can be dissociated into B radical, $B^+$ ion, Cl radical and $Cl^+$ ion. However, the $BCl_3$ molecule can be dissociated into B radical or $B^+$ ion easier than Cl radical or $Cl^+$ ion. First, we evaluated the etch behaviors of sapphire wafer in $BCl_3$/additive gases (Ar, $N_2,Cl_2$) gases. The behavior of etch rate of sapphire substrate was monitored as a function of additive gas ratio to $BCl_3$ based plasma, total flow rate, r.f. power, d.c. bias under different pressures of 5 mTorr, 10 mTorr, 20 mTorr and 30 mTorr. The etch rates of sapphire wafer, $SiO_2$ and PR were measured with using alpha step surface profiler. In order to understand the changes of radicals, volume density of Cl, B radical and BCl molecule were investigated with optical emission spectroscopy (OES). The chemical states of $Al_2O_3$ thin films were studied with energy dispersive X-ray (EDX) and depth profile anlysis of auger electron spectroscopy (AES). The enhancement of sapphire substrate can be explained by the reactive ion etching mechanism with the competition of the formation of volatile $AlCl_3$, $Al_2Cl_6$ or $BOCl_3$ and the sputter effect by energetic ions.

• 센서학회지
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• 제4권3호
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• pp.80-88
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• 1995

본 논문에서는 Al 및 TiW 금속을 상하층 전극으로 사용하고 이들 금속사이에 절연물이 존재하는 금속-절연물-금속(metal-insulator- metal : MIM) 구조의 안티휴즈 소자를 만들고 금속층간 절연물의 성질에 따른 안티휴즈 특성에 대하여 연구하였다. 금속층간 절연물로는 R.F 스퍼터링법에의해 형성된 실리콘 산화막과 탄탈륨 산화막으로 구성된 이층 절연물을 사용하였다. 이러한 안티휴즈 구조에서 실리콘 산화막은 프로그램 전의 안티휴즈 소자를 통해 흐르는 누설전류를 감소시켰으며, 실리콘 산화막에 비해 절연 강도가 낮은 탄탈륨 산화막은 안티휴즈 소자의 절연파괴전압을 저 전압으로 낮추는 역할을 하였다. 최종적으로 제조된 $Al/Ta_{2}O_{5}(10nm)/SiO_{2}(10nm)/TiW$ 구조에서 1 nA 이하의 누설전류와 약 9V의 프로그래밍 전압을 갖고 수 초내에 프로그램이 완성되는 전기적 특성이 안정된 안티휴즈 소자를 제조하였다. 그리고 이때 소자의 OFF 및 ON 저항은 각각 $3.65M{\Omega}$ 및 $7.26{\Omega}$이었다. 이와 같은 $Ta_{2}O_{5}/SiO_{2}$ 구조에서 각 절연물의 두께를 조절함으로써 측정 전압에 민감하고 재현성 있는 안티휴즈 소자를 제조할 수 있었다.