• Transactions on Electrical and Electronic Materials
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• v.16 no.1
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• pp.34-36
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• 2015

Amorphous SiZnSnO(SZTO) thin film transistors(TFTs) have been fabricated by RF magnetron sputtering process, and they were annealed in air and in wet ambient. The electrical performance and the structure were analyzed by I-V measurement, XPS, AFM, and XRD. The results showed improvement in device performance by wet annealing process compared to air annealing treatment, because free electron was shown to be increased due to reaction of oxygen and hydrogen generating oxygen vacancy. This is understood by the generation of free electrons. We expect the wet annealing process to be a promising candidate to contributing to high electrical performance of oxide thin film transistors for backplane device applications.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.26 no.5
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• pp.373-379
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• 2013

Mg-doped zinc tin oxide (ZTO:Mg) thin films were prepared on glasses by rf magnetron sputtering. $O_2$ was introduced into the chamber during the sputtering. The optical properties of the films as a function of oxygen flow rate were studied. The crystal structure, elementary properties, and depth profiles of the films were investigated by X-ray diffraction (XRD), x-ray photoelectron spectroscopy (XPS), and secondary ion mass spectrometry (SIMS), respectively. Bottom-gate transparent thin film transistors were fabricated on $N^+$ Si wafers, and the variation of mobility, threshold voltage etc. with the oxygen flow rate were observed.

• Proceedings of the Korean Vacuum Society Conference
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• 2010.08a
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• pp.71-71
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• 2010

Copper oxide thin films were deposited on the p-type Si(100) by r.f. magnetron sputtering as a function of different substrate temperature. The deposited copper oxide thin films were investigated by atomic force microscopy (AFM), scanning electron microscopy (SEM), spectroscopic ellipsometry (SE), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS). The SEM and SE data show that the thickness of the copper oxide films was about 170 nm. AFM images show that the surface roughness of copper oxide films was increased with increasing substrate temperature. As the substrate temperature increased, monoclinic CuO (111) peak appeared and the crystal size decreased while the monoclinic CuO (-111) peak was independent on the substrate temperature. The oxidation states of Cu 2p and O 1s resulted from XPS were not affected on the substrate temperature. The contact angle measurement was also studied and indicated that the surface of copper oxide thin films deposited high temperature has more hydrophobic surface than that of deposited at low temperature.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2003.07a
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• pp.19-27
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• 2003

Morphology and composition of MgO films grown on single-crystalline diamond (100) have been studied. MgO thin films were deposited in the substrate temperature range from room temperature (RT) to 723K by means of electron beam evaporation using MgO powder source. Atomic force microscopy images indicated that the film grown at RT without $O_2$ supply was relatively uniform and flat whereas that deposited in oxygen ambient yielded higher growth rates and rough surface morphologies. X-ray photoelectron spectroscopy analyses demonstrate that the MgO film deposited at RT without $O_2$ has the closest composition to the stoichiometric MgO, and that a thin contaminant layer composed mainly of magnesium peroxide (before etching) or hydroxide (after etching) was unintentionally formed on the film surface, respectively. These results will be discussed in relation to the interaction among the evaporated species and intentionally supplied oxygen molecules at the growth front as well as the interfacial energy between diamond and MgO.

• Proceedings of the KIEE Conference
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• 2002.07c
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• pp.2020-2022
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• 2002

SiC direct bonding technology is very attractive for both SiCOI(SiC-on-insulator) electric devices and SiC-MEMS fileds because of its application possibility in harsh environements. This paper presents on pre-bonding according to HF pre-treatment conditions in SiC wafer direct bonding using PECVD oxide. The PECVD oxide was characterized by XPS and AFM, respectively. The characteristics of bonded sample were measured under different bonding conditions of HF concentration and applied pressure, respectively. The bonding strength was evaluated by tensile strength method. Components existed in the interlayer were analyzed by using FT-IR. The bond strength depends on the HF pre-treatment condition before pre-bonding (Min : 5.3 kgf/$cm^2{\sim}$ Max : 15.5 kgf/$cm^2$).

• Journal of the Korean institute of surface engineering
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• v.29 no.6
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• pp.728-734
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• 1996

To obtain the relation in the electrochemical reduction of $CO_2$ in aqueous $KHCO_3$ colution between an activity for the product and the nature of Cu electrode, the electrode surface was characterized by using two methods: X-ray photoelectron spectroscopy (XPS) and photoelectron emission (PE) measurement. Electrolyses were performed with Cu electrodes pretreated in several ways. The distribution of the products changed drastically with electrolysis time and the pretreatment method. The features in XPS spectra were closely connected with the product distribution. The oxide film at the electrode surface was gradually reduced to bare Cu metal with electrolysis time, resulting in a variation of the product distribution. PE was measured by verying the wavelength of incident light at several temperatures. The dependence of PE on the measurement temperature changed greatly before and after electrolysis.

• Journal of the Korean Vacuum Society
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• v.2 no.1
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• pp.28-33
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• 1993

산화분위기에서의 Ti/SiO2 박막의 산화거동 및 계면반응을 조사했다. SiO2막위에 100nm의 티타니움을 스퍼터법으로 형성하여 급속가열로(Rapid Thermal Processor)에서 온도를 달리하여 산화시켰다. 산화거동은 박막의 면저항의 측정, 산화막 두께측정, XPS(X-ray Photoelectron Spectroscopy)에 의한 조성분석으로 평가했다. 산화시 티타니움 면저항은 표면에서 산화로 인해 약 $500^{\circ}C$ 이상에서 증가하기 시작해서 $800^{\circ}C$에서 포화되었다. 이 때 막두께는 약 $700^{\circ}C$ 이상에서 약 2배로 증가한 후 일정한 두께를 나타내었다. 이 결과로부터 산화부산물에 도전성물질이 존재하는 것을 알 수 있었다. TEM과 XPS분석결과 40$0^{\circ}C$ 이상에서 산화시 Ti 표면에서부터 TiO2가 형성되고 $600^{\circ}C$ 이상에서는 TiO2의 형성과 Si의 석출이 확인되었다. 석출되는 Si의 양은 온도에 따라 증가했다.

• Journal of the Korean Vacuum Society
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• v.4 no.3
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• pp.261-269
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• 1995

본 실험에서는 실리콘 웨이퍼 위에 photoresist(PR)와 octadecyltrichlorosilane(OST, CH3((CH2)17SiCI3)를 입혀서 UV/zone 처리를 어떻게 유기물질들이 UV/zone과 반응하여, 어떻게 표면에서 제거되는지를 in-line으로 연결된 XPS로 분석하고 반응시킨 표면들의 거칠기(roughness)를 AFM을 이용하여 관찰하였다. 실험결과 상온에서 UV/zone 처리를 했을 경우, PR과 OTS같은 유기물질이 표면에서 산화되는 것을 알 수 있었으나 이들이 제거되지 않고 표면에 그대로 남아있음을 알 수 있었다. 그러나 가열하면서(PR:$250^{\circ}C$, ORS:$100^{\circ}C$)UV/ozone 처리를 하였을 경우 표면에서 산화됨과 동시에 이들 산화물들이 표면에서 제거됨을 알 수 있었다. XPS 분석으로부터 이들의 산화반응물은 PR과 OTS 모두 -CH2-, -CH2O-, =C=O, -COO-를 가지는 것으로 나타났으며, 열에너지에 의해서 이들이 표면에서 제거되는 것으로 나타났다. AFM 분석결과는 상온에서 UV/ozone 처리를 하였을 경우에 표면의 거칠기가 적은 반면, 가열하면서 UV/o-zone처리를 하였을 경우에는 표면의 거칠기가 다소 증가하였다.

• Journal of the Korean Vacuum Society
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• v.3 no.3
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• pp.264-268
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• 1994

본연구에서는 HCl 또는 NH4OH로 산화막을 식각학 GaAs 표면에 H2S 가스를 이용하여 유황처 리하였다. 표면의 화학적 조성 및 결합상태를 측정하기 위하여 AES 및 XPS를 사용하였다. 시편들은 30,200 및 $350^{\circ}C$로 가열하면서 H2S가스와 반응시켰다. 이때 유황은 GaAs 표면의 Ga 원자 및 As 원자 와 화학결합을 형성하고 있음이 밝혀졌다. 또한 $350^{\circ}C$로 가열된 시편이 $30^{\circ}C$ 또는 $200^{\circ}C$로 가열된 시편 보다 표면에 결합된 유황의 양이 많은 것으로 나타났다. 아울러 (NH4)2S 수용액 또는 Na2S 수용액으로 유황처리된 경우와 동일하게 H2S 가스로 유황처리된 GaAs 표면에서는 Ga 산화막 및 As 산화막이 거 의 관측되지 않았다.

• Journal of the Korean Vacuum Society
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• v.1 no.1
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• pp.50-59
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• 1992

By means of X-ray photoelectron spectroscopy(XPS), the initial stages of the oxidation of the cleaved CdTe (110) surface and the sputtered CdTe surface with oxygen exposure are invetigated. From the analyses of the spectra of Te 3dsn, Cd 3d5/2, 0 ls and Cd MNN Auger lines, it is shown that two oxygen atoms bond to one Te atom at the initial stages.