• ETRI Journal
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• 제27권5호
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• pp.551-556
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• 2005

We have demonstrated a high-power widely tunable sampled grating distributed Bragg reflector (SGDBR) laser integrated monolithically with a semiconductor optical amplifier (SOA) having a lateral tapered waveguide, which is the first to emit a fiber-coupled output power of more than 10 dBm using a planar buried heterostructure (PBH). The output facet reflectivity of the integrated SOA using a lateral tapered waveguide and two-layer AR coating of $TiO_2\;and\;SiO_2$ was lower than $3\;{\times}\;10^{-4}\;over$ a wide bandwidth of 85 nm. The spectra of 40 channels spaced by 50 GHz within the tuning range of 33 nm were obtained by a precise control of SG and phase control currents. A side-mode suppression ratio of more than 35 dB was obtained in the whole tuning range. Fiber-coupled output power of more than 11 dBm and an output power variation of less than 1 dB were obtained for the whole tuning range.

• ETRI Journal
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• 제24권6호
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• pp.462-464
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• 2002

This paper presents a serial interface circuit that permits selection of the amount of data converted from serial-to-parallel and parallel-to-serial and overcomes the disadvantages of the conventional serial input/output interface. Based on the selected data length operating mode, 8 bit or 16 bit serial-to-parallel and 8 bit or 16 bit parallel-to-serial conversion takes place in data blocks of the selected data length.

• ETRI Journal
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• 제27권2호
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• pp.133-139
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• 2005

A monolithic microwave integrated circuit (MMIC) chip set consisting of a power amplifier, a driver amplifier, and a frequency doubler has been developed for automotive radar systems at 77 GHz. The chip set was fabricated using a 0.15 ${\mu}$ gate-length InGaAs/InAlAs/GaAs metamorphic high electron mobility transistor (mHEMT) process based on a 4-inch substrate. The power amplifier demonstrated a measured small signal gain of over 20 dB from 76 to 77 GHz with 15.5 dBm output power. The chip size is 2mm${\times}$ 2mm. The driver amplifier exhibited a gain of 23 dB over a 76 to 77 GHz band with an output power of 13 dBm. The chip size is 2.1mm${\times}$ 2mm. The frequency doubler achieved an output power of -6 dBm at 76.5 GHz with a conversion gain of -16 dB for an input power of 10 dBm and a 38.25 GHz input frequency. The chip size is 1.2mm ${\times}$ 1.2mm. This MMIC chip set is suitable for the 77 GHz automotive radar systems and related applications in a W-band.

• ETRI Journal
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• 제27권5호
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• pp.569-578
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• 2005

The purpose of this paper is to describe the implementation of monolithically matching circuits, interface circuits, and RF core circuits to the same substrate. We designed and fabricated on-chip 1 to 6 GHz up-conversion and 1 to 8 GHz down-conversion mixers using a 0.8 mm SiGe hetero-junction bipolar transistor (HBT) process technology. To fabricate a SiGe HBT, we used a reduced pressure chemical vapor deposition (RPCVD) system to grow a base epitaxial layer, and we adopted local oxidation of silicon (LOCOS) isolation to separate the device terminals. An up-conversion mixer was implemented on-chip using an intermediate frequency (IF) matching circuit, local oscillator (LO)/radio frequency (RF) wideband matching circuits, LO/IF input balun circuits, and an RF output balun circuit. The measured results of the fabricated up-conversion mixer show a positive power conversion gain from 1 to 6 GHz and a bandwidth of about 4.5 GHz. Also, the down-conversion mixer was implemented on-chip using LO/RF wideband matching circuits, LO/RF input balun circuits, and an IF output balun circuit. The measured results of the fabricated down-conversion mixer show a positive power conversion gain from 1 to 8 GHz and a bandwidth of about 4.5 GHz.

• ETRI Journal
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• 제25권4호
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• pp.270-273
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• 2003

This paper presents a simple process to integrate thin-film inductors with a bottom NiFe magnetic core. NiFe thin films with a thickness of 2 to 3${\mu}m$ were deposited by sputtering. A polyimide buffer layer and shadow mask were used to relax the stress of the NiFe films. The fabricated double spiral thin-film inductor showed an inductance of 0.49${\mu}H$ and a Q factor of 4.8 at 8 MHz. The DC-DC converter with the monolithically integrated thin-film inductor showed comparable performances to those with sandwiched magnetic layers. We simplified the integration process by eliminating the planarization process for the top magnetic core. The efficiency of the DC-DC converter with the monolithic thin-film inductor was 72% when the input voltage and output voltage were 3.5 V and 6 V, respectively, at an operating frequency of 8 MHz.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2002년도 ITC-CSCC -3
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• pp.1555-1557
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• 2002

We have investigated the precharge type sense amplifier, it is suitable fur voltage sensing in a NOR type single transistor ferroelectric field effect transistor (1T FeFET) memory read operation. The proposed precharge type sense amplifier senses the bit line voltage of 1T FeFET memory. Therefore, the reference celt is not necessary compared to current sensing in 1T FeFET memory, The high noise margin is wider than the low noise margin in the first inverter because requires tile output of precharge type sense amplifier high sensitivity to transition of input signal. The precharge type sense amplifier has very simple structure and can sense the bit line signal of the 1T FeFET memory cell at low voltage.

• 기술혁신학회지
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• 제13권4호
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• pp.656-679
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• 2010

우리나라에서 기초연구에 대한 지원이 본격적으로 이루어진 것은 1990년 기초과학연구진흥법이 시행되면서부터 이다. 이후 90년대에 기초연구에 대한 지원이 확대되기 시작하였고, 이러한 추세는 21세기에 들어서면서 더욱 가속화되었다. 그 결과 기초연구의 대표적 연구성과인 SCI 논문도 크게 증가하였다. SCI 논문수는 2008년에 35,569편으로서 세계전체의 2.42%를 점유하는 등 양적으로 큰 성장을 이룩하여 왔다. 그러나 이러한 양적인 성장에도 불구하고 논문 피인용횟수로 나타나는 질적인 측면은 세계 30위권에 머무르고 있는 실정이다. 본 연구는 이러한 문제점을 해결하기 위해 교육과학기술부의 기초연구사업을 중심으로 연구관리의 범주기획 지원 평과 관리 성과확산 중에서 지원, 평가, 성과확산에 관한 개선방안을 제시하고자 한다. 특히 연구지원사업구조의 개편과 평가제도의 개선 그리고 기술료제도의 개선방안을 제시하고자 한다.

• 기술경영경제학회:학술대회논문집
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• 기술경영경제학회 1997년도 제11회 하계학술발표회 논문집
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• pp.160-171
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• 1997

This paper starts out by reviewing the literature that in different ways utilizes patent data as a output of R&D investment. The main focus, however, is an analysis of time-lag between R&D input and output. To achieve this research objective, the basic data associated with the R&D input(expenditure, researchers) and output(patent, utilities) for the past 15 years, from 1980 to 1994, in the areas of electrical-electronic, mechanical and chemical industries have been collected. And the raw output data were altered it to objective data using Laspeyres approach and analyzed using multiple regression analysis, especially stepwise regression analysis. The result of this study can be summarized as follows: a) The time-lag between R&D input and output is from 1 to 4 years. This result is equal to the research conclusion of the existing foreign studies. b) It was found that the time-lag of patents was longer than of utility models. c) It was showed that the time-lag of electrical-electronic, mechanical industry was longer than the chemical one.

• 기술혁신연구
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• 제7권1호
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• pp.176-186
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• 1999

This paper starts out by reviewing the literature that in different ways utilizes patent data as an output of Research ＆ Development (R&D) investment. The main focus, however, is an analysis of time-lag between industrial R&D input and its output. To achieve this research's purpose, the basic data associated with the industrial R&D input (expenditure, researchers) and output (applied patent and utilities) for the past 15 years, from 1980 to 1994, in the areas of electrical-electronic, mechanical and chemical industries have been collected. And the raw input data were altered into real flow data (but stock data) using Laspeyres approach and analyzed using multiple regression analysis, especially stepwise regression analysis. The result of this study can be summarized as follows: a) The time-lag; between industrial R&D input and its output is within 1 to 3 years. b) The time-lag: of patents was longer than that of utility models. c) The time-lag: in electrical-electronic, chemical industry was longer than that of the mechanical industry.

• Asian Journal of Innovation and Policy
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• 제6권2호
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• pp.152-169
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• 2017

In this paper, we analyze the basic research system in South Korea. We propose a national basic research system consisting of value, openness, input, transformation, and output. Based on this framework, we set up interview questionnaires, and 15 key informants have been interviewed. According to our results, first, in terms of value, basic research is recognized as an activity for creating knowledge in the understanding of nature. Second, as for openness, scientists and policy experts agree that active interaction with the global community is an important value for the national research system. Third, in terms of sustainable research resources, scientists are strongly required to effectively allocate research funding, maximizing the creativity of researchers and the efficient sharing of research equipment. Fourth, in transformation, basic researchers maintain that the Korean research system has is extremly dependent on the government's external control, and its self-regulative system has been weak for over half century onw. Fifth, for global competitiveness, the interviewees agreed that the quality of basic research in Korea is approaching that of its global competitors. Finally, we put forward some policy implications on the basis of these findings.