• Title/Summary/Keyword: MIS 5a

Search Result 256, Processing Time 0.024 seconds

Efficiency Improvement of Al-MIS Solar Cell Using Texturization (Texturization을 이용한 Al-MIS 태양 전지의 효율 개선)

  • Kim, Jin-Seop;Lee, U-Il;Kim, Gi-Wan;Jeong, Ho-Seon
    • Journal of the Korean Institute of Telematics and Electronics
    • /
    • v.19 no.5
    • /
    • pp.26-31
    • /
    • 1982
  • Texturization technique has been employed to improve the efficiency of Al-MIS solar cells. The best condition for the formation of insulating layer was 50$0^{\circ}C$ in N2 ambient for 20 minutes, and the appropriate thickness of the Al barrier metal layer was about 100$\AA$ For the texturization of the face a mixture of hydrazinehydrate and pyrocathecol was used. The efficiency improvement of the texturized cells ranged from 1.2 to 1.6% under 100mW/$\textrm{cm}^2$ illumination.

  • PDF

A Study on Hydrogen Detection Characteristics of the Pt-MIS Capacitor Device (Pt-MIS 커패시터 소자의 수소가스 검지특성 연구)

  • Sung, Yung-Kwon;Yi, Seung-Hwan;Koh, Jung-Hyuk;Rhie, Dong-Hee
    • The Transactions of the Korean Institute of Electrical Engineers C
    • /
    • v.48 no.2
    • /
    • pp.69-75
    • /
    • 1999
  • The characteristics of $H_2$ gas detection have been investigated using the Pt-MIS capacitor composed of the LPCVD nitride on the oxide. The flat band voltage shift is measured as 0.1 V in 1,000 ppm $H_2$ gas ambient and to be independent of Pt catalyst thickness. It is found that the flatband voltage shift is proportional to the hydrogen concentrations. The response and recovery time of Pt-MIS capacitor are 5 mins and 25 mins respectively. The samples of 30nm thick Pt revealed much higher sensitivity than that of 150nm samples. The samples of 150nm Pt showed that the flatband voltage shift of the device is due to the formation of the dipole layer of the adsorbed hydrogen atoms at the Pt-insulator interface.

  • PDF

Revisiting the OSL Ages of Marine Terrace Sediments at Suryum Fault Site, Gyeongju, South Korea: Single Grain OSL Dating (수렴단층노두 해안단구 퇴적층의 OSL 연대에 대한 재고찰: 단일입자 OSL 연대측정 연구)

  • Heo, Seoyoung;Choi, Jeong-Heon;Hong, Duk-Geun
    • The Journal of the Petrological Society of Korea
    • /
    • v.23 no.3
    • /
    • pp.187-195
    • /
    • 2014
  • In this paper, we report new OSL ages of the marine terrace sediments at Suryum fault site, using single grains of quartz, and briefly discuss their chronological implications on the timing of terrace formation along the southeastern coast of Korea. Of 1200 grains measured, 93 quartz grains were found to have OSL properties suitable for dating, the equivalent dose ($D_e$) values of which varied significantly, ranging from 50 Gy to 610 Gy with the overdispersion of $30{\pm}4%$. Applied to the Central Age Model (CAM) and Minimum Age Model (MAM), these quartz grains showed the OSL ages of $83{\pm}4ka$ and $60^{+3}{_{-7}}ka$, respectively, both of which are stratigraphically inconsistent with the previously reported OSL ages of lower $2^{nd}$ terrace (MIS 5a; ~80 ka). However, Finite Mixture Model (FMM) revealed that a small fraction of the measured quartz grains ($6{\pm}4%$) were of the ages ($194{\pm}24ka$) corresponding to MIS 7. Conclusively, based on single grain OSL ages, it would be prudent not to exclude the possibility that the marine terrace sediments at Suryum fault site have formed during MIS 7. Further, our single grain OSL ages imply that multiple grain(single aliquot) OSL dating methods are not applicable to the marine sediments at Suryum fault site.

Effects of hydrogen gas addition on insulator thin film of Al/AlN/GaAs MIS system fabricated by sputtering method (스퍼터링법으로 저작한 Al/AlN/GaAs MIS 구조에서 절연박막에 수소가스첨가가 미치는 영향)

  • Kwon, Jung-Youl;Kim, Min-Suk;Kim, Jee-Gyun;Lee, Hwan-Chul;Lee, Heon-Yong
    • Proceedings of the KIEE Conference
    • /
    • 1999.07d
    • /
    • pp.1925-1927
    • /
    • 1999
  • At the study, it has fabricated Al/AlN/GaAs MIS capacitor using DC reactive sputtering method. To applicate GaAs semiconductor in a MIS devices, investigated capability of AIN thin film by the insulator layer. Also it has investigated inversion of C-V characteristics by addition of the hydrogen(hydrogen concentration: 5%) and it has investigated that leakage current has $10^{-8}A/cm^2$ for 1 MV/cm breakdown electric field of I-V characteristics.

  • PDF

Electrical Properties of MIM and MIS Structure using Carbon Nitride Films

  • Lee, Hyo-Ung;Lee, Sung-Pil
    • Transactions on Electrical and Electronic Materials
    • /
    • v.7 no.5
    • /
    • pp.257-261
    • /
    • 2006
  • Nano-structured carbon nitride $(CN_x)$ films were prepared by reactive RF magnetron sputtering with a DC bias at various deposition conditions, and the physical and electrical properties were investigated. FTIR spectrum indicated an ${alpha}C_3N_4$ peak in the films. The carbon nitride film deposited on Si substrate had a nano-structured surface morphology. The grain size was about 20 nm and the deposition rate was $1.7{\mu}m/hr$. When the $N_2/Ar$ ratio was 3/7, the level of nitrogen incorporation was 34.3 at%. The film had a low dielectric constant. The metal-insulator-semiconductor (MIS) capacitors that the carbon nitride was deposited as insulators, exhibited a typical C-V characteristics.

Characteristics of InSb MIS device prepared by remote PECVD SiO$_{2}$ (Remote PECVD SiO$_{2}$ 를 이용한 InSb MIS 소자의 특성)

  • 이재곤;최시영
    • Journal of the Korean Institute of Telematics and Electronics A
    • /
    • v.33A no.12
    • /
    • pp.59-64
    • /
    • 1996
  • InSb MIS devices prepared by remote PECVD SiO$_{2}$ were fabricated. The SiO$_{2}$ films on InSb were deposited at atemperature range of 67~190$^{\circ}$C. The effects of deposition temperature on the structural characteristics of the SiO$_{2}$ films evaluated Auger electron spectroscopy showed that atomic raito of silicon to oxygen was 0.5 and composition toms were distributed uniformaly throuout the oxide film. The transition region is about 100$\AA$ for SiO$_{2}$/InSb interface. The leakage current density at 1MV/cm and the breakdownelectric field of the MiS device using SiO$_{2}$ film deposited at 105$^{\circ}$C were about 22 nA/cm$^{2}$ and 3.5MV/cm, respectively. The interface-state density at mid-bandgap extracted from 1 MHz high frequency C-V measurement was about 2X10$^{11}$ cm$^{-2}$eV$^{-1}$.

  • PDF

Disproof of Hadwiger Conjecture (Hadwiger 추측의 반증)

  • Lee, Sang-Un
    • The Journal of the Institute of Internet, Broadcasting and Communication
    • /
    • v.14 no.5
    • /
    • pp.263-269
    • /
    • 2014
  • In this paper, I disprove Hadwiger conjecture of the vertex coloring problem, which asserts that "All $K_k$-minor free graphs can be colored with k-1 number of colors, i.e., ${\chi}(G)=k$ given $K_k$-minor." Pursuant to Hadwiger conjecture, one shall obtain an NP-complete k-minor to determine ${\chi}(G)=k$, and solve another NP-complete vertex coloring problem as a means to color vertices. In order to disprove Hadwiger conjecture in this paper, I propose an algorithm of linear time complexity O(V) that yields the exact solution to the vertex coloring problem. The proposed algorithm assigns vertex with the minimum degree to the Maximum Independent Set (MIS) and repeats this process on a simplified graph derived by deleting adjacent edges to the MIS vertex so as to finally obtain an MIS with a single color. Next, it repeats the process on a simplified graph derived by deleting edges of the MIS vertex to obtain an MIS whose number of vertex color corresponds to ${\chi}(G)=k$. Also presented in this paper using the proposed algorithm is an additional algorithm that searches solution of ${\chi}^{{\prime}{\prime}}(G)$, the total chromatic number, which also remains NP-complete. When applied to a $K_4$-minor graph, the proposed algorithm has obtained ${\chi}(G)=3$ instead of ${\chi}(G)=4$, proving that the Hadwiger conjecture is not universally applicable to all the graphs. The proposed algorithm, however, is a simple algorithm that directly obtains an independent set minor of ${\chi}(G)=k$ to assign an equal color to the vertices of each independent set without having to determine minors in the first place.

A Case of Multisystem Inflammatory Syndrome in Children (MIS-C) with Acute Myocarditis

  • Lim, Jin Gyu;Lee, Da Hye;Oh, Kyung Jin;Choi, Sujin;Song, Young Hwan;Lee, Joowon;Lee, Hyunju
    • Pediatric Infection and Vaccine
    • /
    • v.28 no.3
    • /
    • pp.173-180
    • /
    • 2021
  • After initial reports of multisystem inflammatory syndrome in children (MIS-C) in April 2020 in Europe, this disease has been known to occur in children with recent history of coronavirus disease 2019 (COVID-19) and most cases have been reported in Europe and the Unites States of America. We report a case of a 14-year-old girl who was diagnosed with MIS-C with acute myocarditis and successfully treated with intravenous immunoglobulin (IVIG), methylprednisolone, and anakinra. At initial presentation, she had persistent high fever, generalized rash, generalized swelling, abdominal pain, and low blood pressure. She showed a remarkably elevated level of inflammation and cardiac enzyme markers and had a previous history of COVID-19 5 weeks before the initial presentation. After extensive work up, other infectious and non-infectious causes were excluded. She was diagnosed with MIS-C and initially treated with IVIG and high-dose methylprednisolone; however, despite treatment, her heart function deteriorated and coronary artery dilatation progressed. Therefore, anakinra, an interleukin-1 receptor antagonist, was administered on hospital day 6, after which her cardiac function exhibited improvement. She was discharged on hospital day 19 without any symptoms, and follow-up echocardiography after 1 month revealed fully recovered heart function with normal coronary arteries.

The Examination of the Limitations of Using the OSL Dates Derived from this Study in the Correlation of MIS 5 Marine Terraces Distributed in the Southeastern Coast of the Korean Peninsula (한반도 남동부 해안 해성단구의 분류와 편년에 있어서 본 연구에서 도출된 OSL 연대 적용의 한계성 검토)

  • Choi, Seong Gil;Tamura, Toshikazu;Miyauchi, Takahiro;Tsukamoto, Sumiko
    • Journal of The Geomorphological Association of Korea
    • /
    • v.25 no.4
    • /
    • pp.63-75
    • /
    • 2018
  • The lower marine terrace 1 and 2 surfaces distributed between Ulsan and Pohang coast in the southeastern coast of the Korean penninsula have been correlated with MIS 5e and 5a (or 5c) by amino acid dates, 14C dates, wide-spread tephra correlation and pollen analysis respectively. In this study, to test the reliability of the OSL method for the estimation of the numerical burial age of marine sediment deposits, we analyzed the samples from the marine terraces which have been known as typical marine terraces formed during MIS 5e and MIS 5a in the above-mentioned coast. The burial ages of the marine deposit of the lower marine terrace 1 and 2, with paleoshoreline altitudes of 18m to 19m and 10m to 11m respectively, both showed about the same age of 60 ka BP. The lower marine terraces 1 and 2, however, were divided into two terrace surfaces by a clear terrace cliff. Besides, the OSL dates of the lower and upper parts of the lower marine terrace 2 of the Bonggil coast showed the reversed burial ages. In the lower marine terrace 1 of the Sanhari coast, almost the same burial ages were derived from both the lower part (marine rounded gravel layer) and the upper part (terrestrial angular gravel layer) of the terrace deposit. Therefore, at the present time, judging from only the OSL dates measured in this study, it could be argued that the OSL method is not the best for the estimation of forming periods of the lower marine terraces 1 and 2 and their classification.

A Comparative Study on the Confidence in Venture Creation between MIS Students and Other Business Major Students in the USA (미국의 경영정보 전공학생 집단과 일반경영 전공학생 집단간의 창업 자신감에 대한 비교연구)

  • 장대성;이지영;임성배
    • Journal of the Korea Society of Computer and Information
    • /
    • v.5 no.4
    • /
    • pp.180-188
    • /
    • 2000
  • This study was conducted to identify the difference in the level of confidence about venture creation between MIS students and those of other business major in the USA. For this study, data were collected from 70 business students including ANOVA, t-test and multiple regression were employed to analyze the collected data. The results of the study show that MIS students who have interdisciplinary knowledge including IT field and business field, have much higher level of confidence about venture creation. The results of this study suggest that MIS education be required to build an effective entrepreneurship education for business major students.

  • PDF