• 한국재료학회지
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• 제12권5호
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• pp.359-362
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• 2002

DBPAS has been used to characterize atomic level defect structures in materials. In this investigation the numerical analysis of the Doppler spectra was restricted to the determination of the shape parameter, S, defined as the ratio between the total amount of counts in a central portion of the spectrum and the total amount of counts. As samples were exposed by X-ray increasing from 3, 6, and 9 Gy with 6 MV, and 10 MV each and also by E-beam increasing the energies with 6 MeV, 9 MeV, 12 MeV, and 20 MeV. The S-parameter values were increased as increasing the exposed time and the energies. The S-parameters of the large and small size grains in $CaWO_4$ were measured. The S-parameter of the small size grains in $CaWO_4$ was resulted in larger values.

• 한국산학기술학회논문지
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• 제10권7호
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• pp.1725-1728
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• 2009

본 연구개발에서는 정해진 환경에서 최대의 불량검출 능력을 발휘할 수 있도록 공정을 개선하기 위하여 전게이트 시각검사에 필수적인 FGV 패턴발생 장치와 공정제어 장치를 개발하였다. 본 연구개발을 통하여 접촉손실(Tact Loss)을 0에 근접 한 수준으로 유지할 뿐만 아니라 손실 및 에러 발생시 신속한 대처가 가능하여 모듈의 수율을 향상시킬 수 있을 것으로 기대된다. 또한 세부 동작 시퀀스를 제어하기 위한 H/W와 S/W 시스템을 생산라인에 실장하고 성능점검 및 인증을 수행한 결과 Tact에 의한 Pixel 불량의 경우는 98.1%, Line 불량의 경우는 99.1%의 검출율을 나타내었으며, Gate 및 Visual 레벨 테스트를 포함한 모듈공정 전체의 수율이 98.3%까지 증가하였다.

• 대한기계학회논문집B
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• 제30권5호
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• pp.397-404
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• 2006

Effects of surface defect distribution on flame instability during flame-surface interaction are experimentally investigated. To examine chemical quenching phenomenon which is caused by radical adsorption and recombination processes on the surface, thermally grown silicon oxide plates with well-defined defect density were prepared. ion implantation technique was used to control the number of defects, i.e. oxygen vacancies. In an attempt to preferentially remove oxygen atoms from silicon dioxide surface, argon ions with low energy level from 3keV to 5keV were irradiated at the incident angle of $60^{\circ}$. Compositional and structural modification of $SiO_2$ induced by low-energy $Ar^+$ ion irradiation has been characterized by Atomic Force Microscopy (AFM) and X-ray Photoelectron Spectroscopy (XPS). It has been found that as the ion energy is increased, the number of structural defect is also increased and non-stoichiometric condition of $SiO_x({\le}2)$ is enhanced.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2004년도 춘계종합학술대회
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• pp.651-654
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• 2004

본 연구에서는 HDL에서 블록 사이, 프로세스문장, 또는 일을 할당하는 순서를 조절하는 상위레벨 사건을 하위레벨 사건과 비교하여 정의하며, 상위레벨 사건은 자원충돌과 프로토콜 또는 사양의존 충돌로 구성된다는 것을 보여준다. 그리고 상위레벨 사건을 검출하기 위하여 2가지 검출방법이 제안된다.

• Journal of Chest Surgery
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• 제28권8호
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• pp.754-758
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• 1995

Between February 1987 and April 1994,30 modified Blalock- Taussing shunts[MBTS were carried out at the Department of Thoracic and Cardiovascular Surgery of the Keimyung University Dongsan Medical Center.The operation consists of interposing between the subclavian artery and the pulmonary artery a polytetrafluoroethylene graft.There were 19 boys and 11 girls.The average age at the time of shunt construction was 14 months [range 4 days to 5 years .Seventy-six percent [23/30 were less than 1 year of age.Cardiac defects treated with MBTS included tetralogy of Fallot[10 , pulmonary atresia with ventricular septal defect[8 , pulmonary atresia with intact ventricular septum[4 , uni-ventricular heart[3 , and other complex cardiac anomalies[5 .Prosthesis of 4mm were used in 13 cases, and 5mm in 17.Of the 30 operations, 21 were performed on the right side and 9 on the left side.The hemoglobin level decreased from 21.1 gm/dl preoperatively to 16.3 gm/dl postoperatively and systemic oxygen saturation level increased from 60.5 % preoperatively to 85.4 % postoperatively.In the 30 patients who recieved MBTS, there were one early [3% and three late deaths [10% .Seven patients have had an corrective operation and two patient required second palliative procedure.The remaining patients are awaiting further operation with ingestion of aspirin [5 mg/kg/day as an antiplatelet agent.These results indicate that the MBTS provide excellent palliation at a low operative mortality for most patients.

• 한국전기전자재료학회논문지
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• 제14권7호
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• pp.557-561
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• 2001

Chemical mechanical polishing (CMP) process has been widely used to planarize dielectric layers, which can be applied to the integraded circuits for sub-micron technology. Despite the increased use of CMP process, it is difficult to accomplish the global planarization of in the defect-free inter-level dielectrics (ILD). Especially, defects such as micro-scratch lead to severe circuit failure which affect yield. CMP slurries can contain particles exceeding 1㎛ in size, which could cause micro-scratch on the wafer surface. The large particles in these slurries may be caused by particles agglomeration in slurry supply line. To reduce these defects, slurry filtration method has been recommended in oxide CMP. In this work, we have studied the effects of filtration and the defect trend as a function of polished wafer count using various filters in inter-metal dielectrics(IMD)-CMP process. The filter installation in CMP polisher could reduce defects after IMD-CMP process. As a result of micro-scratch formation, it is shown that slurry filter plays an important role in determining consumable pad lifetime. The filter lifetime is dominated by the defects. We have concluded that slurry filter lifetime is fixed by the degree of generating defects.

• Journal of Korean Neurosurgical Society
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• 제30권10호
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• pp.1237-1240
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• 2001

Spontaneous herniation of the spinal cord is a very rare. It's clinical symptom presents with progressive myelopathy. A 42-year old male patient who presented the progressive left leg weakness and Brown-Seqaurd syndrome is presented. MRI showed a typical finding of dural defect and herniation of the cord on the level of T3-4. Repair of dural defect using an artificial dura and reposition of cord herniation were undertaken after three level laminectomies with SSEP monitoring. Postoperatively, symptoms were improved rapidly. In our knowledgement, this is first case being reported in Korea. This entity, although rare, should be considered in the differential diagnosis of myelopathy in the absence of a mass lesion.

• Journal of Korean Neurosurgical Society
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• 제54권4호
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• pp.355-358
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• 2013

Spinal extradural arachnoid cyst (SEAC) is a rare disease and uncommon cause of compressive myelopathy. The etiology remains still unclear. We experienced 2 cases of SEACs and reviewed the cases and previous literatures. A 59-year-old man complained of both leg radiating pain and paresthesia for 4 years. His MRI showed an extradural cyst from T12 to L3 and we performed cyst fenestration and repaired the dural defect with tailored laminectomy. Another 51-year-old female patient visited our clinical with left buttock pain and paresthesia for 3 years. A large extradural cyst was found at T1-L2 level on MRI and a communication between the cyst and subarachnoid space was illustrated by CT-myelography. We performed cyst fenestration with primary repair of dural defect. Both patients' symptoms gradually subsided and follow up images taken 1-2 months postoperatively showed nearly disappeared cysts. There has been no documented recurrence in these two cases so far. Tailored laminotomy with cyst fenestration can be a safe and effective alternative choice in treating SEACs compared to traditional complete resection of cyst wall with multi-level laminectomy.

• 한국전기전자재료학회논문지
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• 제16권11호
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• pp.969-974
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• 2003

HgGa$_2$S$_4$ single crystals were grown by the chemical transport reaction method. The HgGa$_2$S$_4$ single crystal crystallized into a defect chalcopyrite structure (I 4). The lattice constants of the single crystal were found to be a = 5.635 $\AA$ and c = 10.473 $\AA$. The direct and indirect optical energy gaps were found to be 2.84eV and 2.78eV, respectively. Photoluminescence peaks of HgGa$_2$S$_4$ single crystal were observed at 2.37 eV, 2.18 eV, and 1.81 eV. In the single crystal, the donor level of 0.25 eV, the acceptor levels of 0.97 eV and 0.41 eV were obtained by TSC, PICTS, and absorption measurements. The photoluminescence peaks were analyzed to relate to the indirect conduction band, the donor level, and the acceptor levels.

• 대한전자공학회논문지
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• 제27권1호
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• pp.68-73
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• 1990

GaAs epilayer was grown on Si(100) substrate using the two-step growth method by MBE. The crystal growth mode have been investigated by RHEED. The hydrogenation effects of GaAs epilayer were studied by DLTS and Raman spectroscopy. The four electron traps in GaAs/Si layer were observed and their activation energy ranged from 0.47 eV to 0.81 eV below the conduction band. After hydrogenation at 250\ulcorner for 3 hours, new trap not observed and electron traps at Ec-0.68, 0.54 and 0.47 eV were almost passivated. Whereas the Ec-0.81 eV level showed no significant change in concentration. From Raman measurement, GaAs epilayer is found to be influenced by the tensile stress.