• 대한전기학회:학술대회논문집
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• 대한전기학회 2009년도 제40회 하계학술대회
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• pp.1240_1241
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• 2009

In this paper, sol-gel-spin coated $Pb(ZrTi)O_3$ thin film with $ZrO_2$ buffer-layer and $PbTiO_3$ seed-layer was investigated for vibration MEMS energy harvester to scavenge power from ambient vibration via d33 piezoelectric mode. Piezoelectric thin film deposition techniques on insulating layer is the important key for $d_{33}$ mode of piezoelectric vibration energy harvester. $ZrO_2$ buff-layer was utilized as an insulating layer. $PbTIO_3$ seed-layer was applied as an inter-layer between PZT and $ZrO_2$ layer to improve the crystalline of PZT thin film. The fabricated PZT thin film had a remanent polarization of 5.3uC/$cm^2$ and the coercive field of 60kV/cm. The fabricated energy harvester using PZT thin film with PTO seed-layer generated 1.1uW of electrical power to $2.2M{\Omega}$ of load with $4.4V_{pvp}$ from vibration of 0.39g at 528Hz.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2006년도 제37회 하계학술대회 논문집 C
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• pp.1303-1304
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• 2006

본 연구에서는 ICP-CVD (inductively coupled plasma chemical vapor deposition)를 이용해 미세결정 실리콘 (nanocrystalline silicon thin film transistor, ns-Si TFT) 초기 성장 단계에 발생하는 비정질의 Incubation layer를 줄이기 위한 실험을 수행하였다. ICP-CVD를 사용하여 증착한 Si-rich $SiN_x$ Seed layer 상의 미세절정 실리콘의 성막조건을 알아보고 특성을 평가하였다. 미세결정 실리콘 박막은 Raman Spectroscopy를 이용해 분석하였다. 미세결정 실리콘의 초기 성장 단계에 발생하는 비정질 Incubation layer를 줄이기 위하여 Si-rich $SiN_x$를 Seed layer로 사용하는 것이 효과적임을 확인하였다. 또한 Si-rich $SiN_x$ 위에서의 미세결정 실리콘 표면 형태와 Seed 성장 기회의 관계를 알아보았다. 높은 전압의 수소 플라즈마 처리는 Seed 성장 기회를 늘이고, 박막의 결정화도를 높임을 확인하였다. 얇은 Incubation layer를 가지는 35nm 이하 두께의 미세결정 실리콘이 성공적으로 증착되었다. 본 연구 결과는 bottom 게이트 방식 박막 트랜지스터에 증착되는 미세결정 실리콘의 전기적 특성 향상에 유용할 것으로 판단된다.

• 한국전기전자재료학회논문지
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• 제22권11호
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• pp.987-991
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• 2009

We report growth of vertically well-aligned zinc oxide (ZnO) nanorods on indium-tin oxide (ITO)/glass substrates using a simple aqueous solution method at low temperature via control of the ZnO seed layer morphology. ZnO nanoparticles acting as seeds are pre-coated on ITO-coated glass substrates. by spin coating to control distribution and density of the ZnO seed nanoparticles. ZnO nanorods were synthesized on the seed-coated substrates in a dipping process into a main growth solution. It was found that the alignment of ZnO nanorods can be effectively manipulated by the spin-coating speed of the seed layer. A grazing incidence X-ray diffraction pattern shows that the ZnO seed layer prepared using the higher spin-coating speed is of uniform seed distribution and a flat surface, resulting in the vertical growth of ZnO nanorods aligned toward the [0001] direction in the main growth process.

• 한국가금학회:학술대회논문집
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• 한국가금학회 2001년도 제18차 정기총회 및 학술발표 PROCEEDINGS
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• pp.54-55
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• 2001

The experiments were conducted to evaluate the feeding values of red pepper seed (Exp. 1) and to investigate its dietary supplementation on layer performances (Exp. 2). The values of TME, TMEn and average TAAA determined by force-feeding 14 roosters (Hy-line) were 2.83 kcal/g, 2.94 kcal/g and 82.72%, respectively. a total of 200 layers (ISA-brown) was divided into 4 groups with 5 replicates of 10 birds per replicate, and fed the experimental diets containing different level of red pepper seed (0, 3, 5, 10%). There were no differences in performances of laying hens among treatments. Liver lipids in all groups containing red pepper seed were significantly reduced as compared to those of control (P＜0.05).

• The Korean Journal of Ecology
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• 제21권6호
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• pp.809-814
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• 1998

Changes of annual seed production related to climate change were studied for 12 years in Piagol, a riparian valley in Mt. Jiri. Sixty-four seed traps (sized 0.5 ${\times}$ 0.5 $m^{2}$) were set up on the forest floor of surveyed area. Seeds were collected from these traps at an interval of 15 days from September to November since 1984. Vegetation of the study area was mainly consisted of the naturally regenerated Carpinus tschonoskii in the tree layer. Acer mono, Quercus serrata, Carpinus laxiflora and Symplocos chinensis also appeared in the same layer. Maximum production occurred in 1984 and 1994. As a result of comparing seed production with local climate factors for 12 years, seed productivity and the year of maximum production of Carpinus forest were merely related with precipitation, air temperature and duration of sunshine among local climate factors. Duration of sunshine was, however, not contributed to periodically high productivity of seed of riparian valley carpinus forest.

• 한국재료학회지
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• 제24권9호
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• pp.443-450
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• 2014

Amorphous (a-Si) films were epitaxially crystallized on a very thin large-grained poly-Si seed layer by a silicide-enhanced rapid thermal annealing (SERTA) process. The poly-Si seed layer contained a small amount of nickel silicide which can enhance crystallization of the upper layer of the a-Si film at lower temperature. A 5-nm thick poly-Si seed layer was then prepared by the crystallization of an a-Si film using the vapor-induced crystallization process in a $NiCl_2$ environment. After removing surface oxide on the seed layer, a 45-nm thick a-Si film was deposited on the poly-Si seed layer by hot-wire chemical vapor deposition at $200^{\circ}C$. The epitaxial crystallization of the top a-Si layer was performed by the rapid thermal annealing (RTA) process at $730^{\circ}C$ for 5 min in Ar as an ambient atmosphere. Considering the needle-like grains as well as the crystallization temperature of the top layer as produced by the SERTA process, it was thought that the top a-Si layer was epitaxially crystallized with the help of $NiSi_2$ precipitates that originated from the poly-Si seed layer. The crystallinity of the SERTA processed poly-Si thin films was better than the other crystallization process, due to the high-temperature RTA process. The Ni concentration in the poly-Si film fabricated by the SERTA process was reduced to $1{\times}10^{18}cm^{-3}$. The maximum field-effect mobility and substrate swing of the p-channel poly-Si thin-film transistors (TFTs) using the poly-Si film prepared by the SERTA process were $85cm^2/V{\cdot}s$ and 1.23 V/decade at $V_{ds}=-3V$, respectively. The off current was little increased under reverse bias from $1.0{\times}10^{-11}$ A. Our results showed that the SERTA process is a promising technology for high quality poly-Si film, which enables the fabrication of high mobility TFTs. In addition, it is expected that poly-Si TFTs with low leakage current can be fabricated with more precise experiments.

• Journal of Plant Biology
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• 제14권1호
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• pp.1-4
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• 1971

To determine the amylase fromation mechanism and the effect of GA. in germinating barley seeds, they were divided into embryo-less seed, isolated embryo, aleurone layer and pure endosperm etc., treated with GA, and cultured separately or in mixed lots. The result obtained are as follows. 1) The amylase of barley seed is formed in the aleurone layer under the effect of inducing materials excreted from the embryo. 2) The embryonic materials amylase formation could be substituted for by GA. Therefore it can be presumed that the substance produced by the embryo which induces amylase synthesis is probably GA or material similar to it.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1995년도 추계학술대회 논문집
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• pp.248-252
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• 1995

In this paper, the samples are made by the new three-composition seed grain method, in order to obtain the low voltage varistor distributed randomly large seed grain in its bulk. The oscillation phenomena of carriers appeared from current-voltage characteristics under knee voltage is shown by the transient flow of non trapped carriers group in the trap level of intergranular layer, surface state and/or depletion layer. Current oscillation phenomena is hardly shown in the high electric field. The injected carriers from both electrodes are directly flowed from the conduction band of forward biased grain through the intergranular layer into the reverse biased grain, because the trap level in the electric field above the knee voltage is mostly filled.

• 한국세라믹학회:학술대회논문집
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• 한국세라믹학회 2000년도 추계총회,초청강연,특별강연,연구발표회
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• pp.64.2-64
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• 2000

• 한국세라믹학회:학술대회논문집
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• 한국세라믹학회 2003년도 추계총회 및 연구발표회 초록집
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• pp.96.1-96
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• 2003