• Proceedings of the Materials Research Society of Korea Conference
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• 2003.03a
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• pp.100-100
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• 2003

본 연구에서는 Si에 Mn을 첨가한 Si$_{l-x}$Mn$_{x}$ 박막의 전기적 및 자기적 특성을 조사하였다. Si$_{l-x}$Mn$_{x}$ 박막은 MBE(Molecular Beam Epitaxy)를 이용하여 native oxide층을 제거하지 않은 (100)Si wafer 위에 성장하였다. Substrate 온도는 50$0^{\circ}C$로 하였으며, 첨가한 Mn 농도는 20%에서부터 80%까지였다. 전기적 특성은 Hall, 4-point probe를 통하여 측정하였고, 자기적 특성은 VSM, FMR, SQUID을 이용하여 측정하였다. 상 분석은 XRD, TEM을 이용하여 관찰하였다 Si$_{l-x}$Mn$_{x}$ 박막은 Hall 측정 결과 상온에서 P-type carrier를 가지며, 비저항은 반도체 영역인 7.6$\times$$10^{-4}$~4.2$\times$$10^{-2}$(ohm-cm)의 값을 가진다. 상온 VSM, 측정결과 Mn의 양이 52% 첨가 시 포화 자화 값이 가장 높은 40emu/cc를 가지며, Mn의 양이 증가할수록 포화 자화 값이 증가하다 다시 감소하는 경향을 가진다. FMR, SQUID 측정에서도 이러한 경향을 확인할 수 있었다 특히, SQUID 분석 결과 두 개 이상의 자성 상이 존재하는 것을 관찰할 수 있었다. XRD, TEM 관찰결과, Si$_{l-x}$Mn$_{x}$은 poly crystal로 성장하였으며, Mn 농도에 따라 여러 상들이 관찰되었다.따라 여러 상들이 관찰되었다.

• Journal of IKEEE
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• v.22 no.2
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• pp.427-431
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• 2018

This research was worked about $Ga_2O_3$ Epi wafer that was one of the mose wide band gap semiconductors to be used power semiconductor industry. This wafer was grown $5.3{\mu}m$ thickness on Sn doped $Ga_2O_3$ Substrate by HVPE(Hydride Vapor Phase Epitaxy). Generally, we can fabricate 600V class power semiconductor devices when the thickness of compoound power semiconductor is $5{\mu}m$. but in case of $Ga_2O_3$ Epi wafer, we can obtain over 1000V class. As a result of J-V measurment of the grown $Ga_2O_3$ Epi wafer, we obtain $2.9-7.7m{\Omega}{\cdot}cm^2$ on resistance. Specially, in case of reverse, we comfirmed a little leakage current when the reverse voltage is over 200V.

• Korean Journal of Materials Research
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• v.4 no.8
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• pp.895-905
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• 1994

The solid phase crystallization behavior of undoped amorphous $Si_{1-x}Ge_{x}$ (X=O to 0.53) alloyfilms was studied by X-ray diffractometry(XRD) and transmission electron microscopy(TEM). Thefilms were deposited on thermally oxidized 5" (100) Si wafer by MBE(Mo1ecular Beam Epitaxy) at 300'C and annealed in the temperature range of $500^{\circ}C$ ~ $625^{\circ}C$. From XRD results, it was found that the thermal budget for full crystallization of the film is significantly reduced as the Ge concentration in thefilm is increased. In addition, the results also shows that pure amorphous Si film crystallizes with astrong (111) texture while the $Si_{1-x}Ge_{x}$ alloy film crystallzes with a (311) texture suggesting that the solidphase crystallization mechanism is changed by the incorporation of Ge. TEM analysis of the crystallized filmshow that the grain morphology of the pure Si is an elliptical and/or a dendrite shape with high density ofcrystalline defects in the grains while that of the $Si_{0.47}Ge_{0.53}$ alloy is more or less equiaxed shape with muchlower density of defects. From these results, we conclude that the crystallization mechanism changes fromtwin-assisted growth mode to random growth mode as the Ge cocentration is increased.ocentration is increased.

• Journal of the Semiconductor & Display Technology
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• v.18 no.3
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• pp.115-121
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• 2019

Response surface methodology (RSM) is used to investigate the complex coupling effects of different operating parameters on silicon growth rate in planetary CVD reactor. Based on the computational fluid dynamics (CFD) model, an accurate RSM model is obtained to predict the growth rate with different parameters, including temperature, pressure, rotation speed of the wafer, and the mole fraction of dichlorosilane (DCS). Analysis of variance is used to estimate the contributions of process parameters and their interactions. Among the four operating parameters that have been studied, the influences of susceptor temperature and the operating pressure were the most significant factors that affect silicon growth rate, followed by the mole fraction of DCS. The influence of wafer rotation is the least. The validation tests show that the results of silicon deposition rate obtained from the regression model are in good agreement with those from CFD model and the maximum deviations is 2.15%.

• Proceedings of the KIEE Conference
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• 1994.07b
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• pp.1463-1465
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• 1994

The electrical characteristics of $Al/Ta_2O_5/Si$ metal-oxide-semiconductor (MOS) capacitors were studied. $Ta_2O_5$ films on p-type silicon had been prepared by ionized cluster beam epitaxy technique (ICBE). This $Ta_2O_5$ films have low leakage current, high breakdown strength and low flat band shift. In this research, a single crystalline cpitaxial film of $Ta_2O_5$ has been grown on p-Si wafer using an ICBE technique. The native oxide layer ($SiO_2$) on the silicon substrate was removed below $500^{\circ}C$ by use of an accelerated arsenic ion beam, instead of a high temperature deposition. $Ta_2O_5$ films formed by ICBE technique can be received considerable attention for applications to coupling capacitors, gate dielectrics in MOS devices, and memory storage capacitor insulator because of their high dielectric constants above 20 and low temperature process.