Ru and ZnO Nanostructures Fabricated by using a Anodic Aluminum Oxide Nanotemplate and Atomic Layer Deposition for Nanosensor Applications (초)

손종역,김우희,박상준,김형준 대한금속재료학회 ( 구 대한금속학회 ) 2007 대한금속재료학회 학술대회 개요집 Vol.2007 No.1

원자 힘 현미경 팁에 의해 분쇄된 PbTiO3 나노점의 강유전 특성의 연구

손종역 한국물리학회 2012 새물리 Vol.62 No.12

We investigated the ferroelectric properties of PbTiO_3 (PTO)nanodots smaller than 10 nm. A 40-nm PTO nanodot was prepared by using dip pen lithography. Then, the 40-nm PTO nanodot was shatteried by using the tip of an atomic force microscope. We used a piezoelectric force microscope to carry out ferroelectric switching experiments on the shattered PTO nanodots. PTO nanodots smaller than 10 nm exhibited good ferroelectric properties with two clear currents that depended on the two ferroelectric polarizations for up to 1,000 cycles. 10 nm보다 작은 PbTiO_3 (PTO) 나노점들의 강유전 특성을연구하였다. 딥팬 리소그래피 (dip pen lithography)로 40 nm PTO 나노점을 제작하고, 원자 힘 현미경 팁 (atomic force microscopy tip,AFM tip)을 이용하여 이 나노점의 분쇄 공정을 실행하였다. 압전력현미경 (piezoresponse force microscope, PFM)을 이용하여 분쇄된나노점들의 강유전 스위칭 실험을 실시하였다. 10 nm보다 작은 PTO 나노점은 두 강유전 분극들에 의존하는 두 전류들의 차이가 명확하게나타나며, 우수한 강유전 특성을 나타내었다.

Epitaxial Layered Cobaltite Na0.5CoO2 Thin Film by Deintercalation of Na0.7CoO2 Thin Film (초)

손종역,김형준,조진형 대한금속재료학회 ( 구 대한금속학회 ) 2007 대한금속재료학회 학술대회 개요집 Vol.2007 No.1

Conducting Atomic Force Microscopy by Half-Metallic Ferromagnetic CrO2-Coated Cantilever

손종역,조진형 한국물리학회 2006 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.49 No.III

We report the characteristics of a half-metallic CrO2-coated cantilever for the application of a conducting atomic force microscope (CAFM). Half-metallic CrO2 on gold-coated Si cantilevers were coated by the CVD method using CrO3 powder as a precursor The half-metallic CrO2 on the gold coated Si cantilever was grown in island growth mode with highly crystallized large grains. A tip radius larger than 40 nm is observed, and this value is slightly increased, compared with the tip radius (30 nm) of a gold-coated tip. The resonance frequency of a half-metallic CrO2-coated cantilever is 20.9 kHz, with a Q-factor of 154.5. This resonance frequency is slightly decreased, compared with the resonance frequency (26 kHz) of a gold-coated cantilever, and the Q factor is slightly increased, compared with the Q factor (149) of a gold-coated cantilever. CAFM images and contact AFM images of (111) Pt thin film on TiO2/SiO2/Si substrate were simultaneously measured, and reproducible results of the CAFM images were obtained after repeated scans.

Substrate Dependence of Glass-to-Crystalline Structural Transition

손종역,조진형,김복기,H.B. Moon,Y.J. Jang 한국물리학회 2005 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.47 No.2

SrRuO3 thin films were grown on amorphous fused silica and (100) LaAlO3 substrates by a pulsed laser deposition method. Amorphous, preferentially oriented and epitaxial SrRuO3 thin films were obtained and were confirmed by X-ray diffraction. For the case of epitaxial growth, the crystallization temperature of SrRuO3 thin film was increased, and this indicates that additional energy is necessary in order to obtain the epitaxial thin film. By using the eclipse method and the control of substrate temperature, the variations of surface morphologies and grain size were observed by atomic force microscope (AFM). Below the crystallization temperature, SrRuO3 thin film shows the hopping transport property of an insulator.

Kelvin probe force microscopy study of epitaxial and polycrystalline PbZr0.53Ti0.47O3 thin films for high density non-volatile storage devices

손종역,조진형,김복기,김철환,H.B. Moon,S.H. Bang,Y.H. Jang 한국물리학회 2005 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.46 No.1

Ferroelectric epitaxial and polycrystalline PbZr0:53Ti0:47O3 thin lms have been studied application for high density storage devices by using the methodology of the scanning probe microscope. It is necessary to bias properly to a SPM tip with low voltage, since the surface charge eect is a dominant eect when a high bias is applied. In addition, if the surface potential at the KFM image is zero after writing by some bias, we can infer that the interaction between the SPM tip and the surface charge is equal to the interaction between the SPM tip and the ferroelectric polarization and then the induced surface charge is over 10-20 C/cm2. The epitaxial thin lms can more easily trap surface charges than the polycrystalline thin lms because polycrystalline thin lms has a lower coercive eld than epitaxial thin lm. To utilize the ferroelectric polarization eect for high-density non-volatile storage devices, criteria are suggested. Ferroelectric epitaxial and polycrystalline PbZr0:53Ti0:47O3 thin lms have been studied application for high density storage devices by using the methodology of the scanning probe microscope. It is necessary to bias properly to a SPM tip with low voltage, since the surface charge eect is a dominant eect when a high bias is applied. In addition, if the surface potential at the KFM image is zero after writing by some bias, we can infer that the interaction between the SPM tip and thesurface charge is equal to the interaction between the SPM tip and the ferroelectric polarization and then the induced surface charge is over 10-20 C/cm2. The epitaxial thin lms can more easily trap surface charges than the polycrystalline thin lms because polycrystalline thin lms has a lower coercive eld than epitaxial thin lm. To utilize the ferroelectric polarization eect for high-density non-volatile storage devices, criteria are suggested.

CVD방법으로 Pt/TiO2/SiO2/Si 기판에 성장시킨 CrO2 박막

손종역,조진형,김경현,문학범,박정우,방석현,송경숙,장영훈 한국물리학회 2004 새물리 Vol.48 No.6

We report dierences in the growth mechanisms of half-metallic CrO2 thin lms deposited on preferentially oriented (111) and (200) Pt/TiO2/SiO2/Si substrates by using chemical vapor deposition method. The CrO2 thin films grown on (111) Pt/TiO2/SiO2/Si substrates were (200) oriented and had crystalline rectangular grains. On the other hand, for (200) Pt/TiO2/SiO2/Si substrates, the CrO2 thin lms were (110) oriented and had wedge-shaped grains. The ferromagnetic domains of the CrO2 thin lms were observed with a magnetic force microscope at room temperature and the orientational dependence of the magnetization was observed using a SQUID magnetometer. While the ferromagnetic domains of both lms showed an in-plane ferromagnetic easy-axis, resulting from shape anisotropy, and orientation of the easy-axis along the in-plane lm direction at the domain boundaries, the magnetic domains showed marked contrast difference at domain boundaries resulting from the dierent surface topographies. Ellipsometery measurements were performed on the CrO2 thin films, and the optical conductivity was obtained from the ellipsometry data. The dependence of the optical conductivity on the photon energy was compared with the band structure calculated using the local spin density approximation.

Ferroelectric Polarization and Surface Charge Trap of Epitaxial SrBi$_2$Ta$_2$O$_9$ and PbZr$_{0.53}$Ti$_{0.47}$O$_3$ Thin Films

손종역,J. H. Cho,S. H. Bang,Y. H. Jang 한국물리학회 2003 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.42 No.IV

Epitaxial ferroelectric thin lms of SrBi2Ta2O9 (SBT) and PbZr0:53Ti0:47O3 (PZT) were deposited on epitaxial La0:5Sr0:5CoO3(LSCO)/(100) LaAlO3 substrate by pulsed laser deposition. The PZT thin lm showed c-axis oriented epitaxial growth. On the SBT thin lms, perpendicular arrangement of rectangular grains was observed with (00l) and relatively larger (220) X-ray diraction peaks than other SBT peaks. Observed by kelvin probe force microscopy (KFM), when a high electric eld is applied on a cantilever, a charge trap is a dominant eect than a ferroelectric polarization resulting from the increase of the surface charge trap due to high electric eld and saturation of remanent polarization. By properly biasing low voltage, the polarization eect is larger than the surface charge trap eect and the sign of the surface potential is reversed indicating a dominant contribution from the ferroelectric polarization.

Molecular scale electronic devices using single molecules and molecular monolayers

손종역,송현욱 한국물리학회 2013 Current Applied Physics Vol.13 No.7

Molecular electronic devices that utilize single molecules or molecular monolayers as active electronic components represent a promising approach in the ongoing miniaturization and integration of electronic devices. Rapid advances in technology have enabled us to engineer molecular electronic devices with diverse functionalities. Significant progress has been made in understanding charge transport in molecular systems at the single-molecule level, and concomitantly, new device concepts have emerged. This review article focuses on experimental aspects of electronic devices made with single molecules or molecular monolayers, with a primary focus on the characterization and manipulation of charge transport.

과학적 추론과 철학적 추론의 비교

박승배,손종역,신영한,박봉규,임영금,박승미,정형준,이후선 범한철학회 2007 汎韓哲學 Vol.47 No.4

Comparison between Scientific Reasoning and Philosophical Reasoning Seungbae Park / Jongyeog Son / Younghan Shin Bonggyu Park / Younggun Im / Seungmee Park Hyeongjun Chung / Huseon Lee Constructive empiricists (van Fraassen, 1989; Ladyman et al., 1997) run the argument from a bad lot and the argument from indifference against inference to the best explanation (IBE). In this paper, we assume that the two arguments are good, and explore disastrous consequences they have on van Fraassen's positive philosophical theories, such as the contextual theory of explanation and constructive empiricism. We show that van Fraassen (1980) uses IBE to establish the contextual theory of explanation. So if a scientific theory goes down, being the product of IBE, so does the contextual theory. The two arguments can be summed up as a request for realists to fight hitherto unconceived rival scientific theories. We argue that if realists have to fight such theories, constructive empiricists would have to fight hitherto unobserved anomalies. So if realism is a problematic position, so is constructive empiricism. Finally, from the above discussion, we draw an important philosophical lesson that there is no difference in structures between scientific reasoning and philosophical reasoning. 문】구성적 경험론자들(van Fraassen, 1989; Ladyman et al., 1997)은 나쁜 부지로부터의 논증(argument from a bad lot)과 무차이로부터의 논증(argument from indifference)을 전개하여 최선의 설명으로의 추리(inference to the best explanation)를 비판한다. 우리는 이 논문에서 그들의 두 논증이 훌륭하다고 가정하고, 설명에 대한 맥락론과 구성적 경험론과 같은 van Fraassen의 철학이론들에 미치는 논리적 재난을 드러내고자 한다. 우리가 보기에, van Fraassen(1980)은 최선의 설명으로의 추리를 이용하여 맥락론을 정당화하고 있다. 따라서 과학이론이 최선의 설명으로의 추리의 산물이라는 이유로 믿을 만한 것이 못된다면 van Fraassen의 맥락론도 마찬가지로 믿을 만한 것이 못된다. 그리고 구성적 경험론자의 위 두 논증은 아직 우리가 생각해내지 못한 경쟁이론들과 싸워보라고 실재론자들에게 요구하는 것으로 요약될 수 있다. 실재론자들이 이런 이론들과 싸워야한다면, 구성적 경험론자들은 우리가 아직 관찰하지 못한 변칙사례들(anomalies)과 싸워야한다고 우리는 주장하겠다. 따라서 실재론이 문제 있는 입장이라면 구성적 경험론도 마찬가지로 문제 있는 입장이다. 마지막으로, 위 논의로부터 과학적 추론과 철학적 추론은 같은 구조를 가지고 있다는 중요한 철학적 교훈을 이끌어내겠다.