• Journal of the Korean Institute of Telematics and Electronics D
• /
• v.36D no.10
• /
• pp.51-60
• /
• 1999

For an effective phase-multiplexing in holographic memory system, four types of phase code used as reference beam are generated. In case of $32 {\times} 32$ address beam, a phase error with 0%, 5%, 10% 15%, 20%, and 25% error rate, is purposely added to the real phase values in order to consider the practical SLM's nonlinear characteristics of phase modulation in computer simulation, cross talks and SNRs are comparatively analysed for these phase-codes by the auto and cross-correlation. Pseudo-Random(PSR) Phase Code has the lowest cross-correlation mean value of 0.067 among four types of Phase Code, which means the SNR of the PSR is higher than other Phase Codes. Also, the standard deviation of the PSR phase code indicating the degree of recalled data degradation is the lowest value of 0.0113.

• JSTS:Journal of Semiconductor Technology and Science
• /
• v.16 no.3
• /
• pp.339-345
• /
• 2016

This paper presents a two-stage power amplifier MMIC using a $0.4{\mu}m$ GaN-HEMT process. The two-stage structure provides high gain and compact circuit size using an integrated inter-stage matching network. The size and loss of the inter-stage matching network can be reduced by including bond wires as part of the matching network. The two-stage power amplifier MMIC was fabricated with a chip size of $2.0{\times}1.9mm^2$ and was mounted on a $4{\times}4$ QFN carrier for evaluation. Using a downlink LTE signal with a PAPR of 6.5 dB and a channel bandwidth of 10 MHz for the 2.6 GHz band, the power amplifier MMIC exhibited a gain of 30 dB, a drain efficiency of 32%, and an ACLR of -31.4 dBc at an average output power of 36 dBm. Using two power amplifier MMICs for the carrier and peaking amplifiers, a Doherty power amplifier was designed and implemented. At a 6 dB back-off output power level of 39 dBm, a gain of 24.7 dB and a drain efficiency of 43.5% were achieved.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2002.07b
• /
• pp.694-698
• /
• 2002

Ti films were deposited onto $100{\times}100$ mm alumina substrates using dc magnetron sputtering under the following conditions; substrate temperature of R.T. ${\sim}400^{\circ}C$, annealing temperature of $100{\sim}400^{\circ}C$ and sputtering gas pressure of $1.3{\sim}3.0{\times}10^{-2}$ Torr. And the films were examined by X-ray diffraction analysis (XRD), scanning electron microscopy(SEM) and 4-point measurement system. The best electrical and structural properties obtained by substrate temperature of ${\sim}200^{\circ}C$, target-substrate distance of ~14 cm and sputtering pressure of $1.3{\sim}1.7{\times}10^{-2}$ Torr. Also at that condition the most excellent adhesion was observed.

• Proceedings of the KIEE Conference
• /
• 2009.07a
• /
• pp.1541_1542
• /
• 2009

본 논문에서는 바이오/환경센서 응용을 위해 실리콘 기판위에 나노 동공구조 백금 전극을 작동전극으로 갖는 소형화된 용존산소센서를 설계 및 제작하고 그 특성을 분석하였다. 제작된 용존산소 센서는 15 mm $\times$ 8 mm $\times$ 0.6 mm의 소형화된 크기를 가졌으며, -0.9 V의 인가전위 시에 각각 산소 포화 상태와 무산소 상태에서 2.14 mA와 0.8 mA의 환원전류 특성을 보였다. 또한, 다양한 산소 농도상태에서 각기 다른 전류응답 차이를 보였다. 이를 통해서 다양한 산소농도에 대한 센싱특성을 검증하였다. 한편, 제작된 용존산소 센서는 전극제작에 사용된 나노 동공구조 백금 전극의 높은 촉매 특성에 기인하여 90% 전류응답시간이 7초 이내로 기발표된 다른 연구들에 비해 현저히 향상된 응답특성을 보였다.

• Proceedings of the Korean Society Of Semiconductor Equipment Technology
• /
• 2004.05a
• /
• pp.259-262
• /
• 2004

투명전극용 ZnO 박막을 펄스레이저 증착방법으로 형성한 후 산소압력과 기판온도에 따른 결정학적, 전기적 특성을 조사하였다. $200^{\circ}C$의 기판온도에서 증착한 ZnO 박막은 C축의 0002 방향으로 우선 배향한 결정구조를 보여주었다. 산소 압력이 10 mTorr 일때 반가폭(FWHM)은 $0.34^{\circ}$의 값을 나타내었다. ZnO 박막의 캐리어 농도는 약 $4\times$10^{20}$\textrm{cm}^3$ 으로 산소농도에는 크게 영향을 받지 않았으며, 약 $5\times10^{-4}{\Omega}cm$ 의 저항율을 나타내었다.

• Proceedings of the Korean Society of Broadcast Engineers Conference
• /
• 2018.06a
• /
• pp.225-226
• /
• 2018

홀로그램 콘텐츠의 정보보안을 위한 암호화 방법을 제안한다. 제안하는 암호화 기법은 실시간 처리를 위해 부분 홀로그램에 대하여 편향치를 더하고, 이중 프레넬 변환을 수행하여 에너지가 집중된 DC 영역을 획득한다. 이때 집중된 영역이 암호화 영역으로 적은 데이터롤 이용하여 고효율의 암호화를 수행한다. 제안한 기법은 기존 연구보다 변환하는 크기를 줄이기 때문에 같은 효율로 고속의 암호화를 수행할 수 있다. $1,024{\times}1,024$ 크기의 홀로그램을 $32{\times}32$ 부분홀로그램으로 구성하여 적용할 경우 약 18배 빠르게 처리할 수 있다.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2000.07a
• /
• pp.608-611
• /
• 2000

Large area plasma source becomes important as the substrate size increases. In this work, four inductively coupled plasma(ICP) unit sources are distributed 2${\times}$2 array. E-ICP concept is applied to the 2${\times}$2 array ICP and its effect is examined. Characteristics of the plasma are measured, and photoresist etching is performed with oxygen plasma. Good etching characteristic in terms of etching rate and uniformity can be obtained with E-ICP.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2006.06a
• /
• pp.157-158
• /
• 2006

$CdS_{0.69}Se_{0.31}$ single crystal grown by sublimation method. Hall effect measurement were carried out by the Van der Pauw method. The measurement values under the temperature were found to be carrier density $n\;=\;1.95\;{\times}\;10^{23}m^3$, Hall coefcient $RH\;=\;-3.21\;{\times}\;10^{-5}m^3/c$, conductivity ${\sigma}\;=\;362.41\;{\Omega}^{-1}m^{-1}$, and Hall mobility ${\mu}\;=\;1.16\;{\times}\;10^{-2}m^2/v.s$.

• Journal of the Korean Graphic Arts Communication Society
• /
• v.29 no.3
• /
• pp.143-153
• /
• 2011

Digital leader caught seat by modern's everyday life tool now by popularization of smart device such as Smart phone and Tablet PC. Therefore, desire of readers about electronic book practical use is increasing based on convenience and economic performance of electronic book. 1971, Michael S. Hart established Project Gutenberg to produced first electronic book because inputs American Independence Declaration Statement by computer and produce more electronic books. After that, an electronic book technology repeats several times development and American electronic book take is increasing rapidly. Sales volume of electronic books is dramatically increasing in Korea since digital device such as Smart phone and Tablet PC became popular. This research attempts to analyze factors influencing on shifting from paper book to electronic book. Results of this research proposed grounds for building business strategy. Finding is the factor of social influence is only significant to acceptability intention. It means user of e-Book enhance their acceptability intention along social phenomena.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2004.11a
• /
• pp.41-44
• /
• 2004

양성자 주입 기술을 pn 다이오드의 동작 속도를 향상시키기 위한 방법 이용하였다. 양성자 주입은 에너지를 2.32 MeV, 2.55 MeV, 2.97 MeV로 변화시키며 수행하여, projection 범위를 각각 접합, 공핍, 중성영역에 위치하도록 하였다. 또한 각각의 에너지 조건에서 도즈를 $1{\times}10^{11}\;cm^{-2}\;1{\times}10^{12}\;cm^{-2},\;1{\times}10^{13}\;cm^{-2}$의 세가지 조건으로 변화시켰다. 양성자 주입 조건 변화에 따른 소자 동작특성의 변화를 관찰하기 위하여 소자의 전류-전압 특성, 용량-전압 특성, 역방향 회복시간 측정을 수행하였다. 분석결과 양성자를 주입하지 않은 소자에 비해 특성의 큰 열화없이 역방향 회복시간을 약 1/5 수준으로 단축시킬 수 있는 것으로 나타났다.