• Journal of the Korean Institute of Telematics and Electronics A
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• v.33A no.7
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• pp.121-126
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• 1996

In this paper an MMIC VCO which can be used in a double conversion TV tuner is designed, fabricated and measured. The VCO is designed using the small signal method and fabricated using ETRI GaAs MMIC foundry. The 3x200$\mu$m gate width MESFET with 1$\mu$m gate length is used for an active device and MIM capacitors, spiral inductors, thin film resitors are used as passive elements. The VCO has output power of 10.95dBm at 1955 MHz with 5V bias voltage and 4V tuning voltage. The oscillation frequency change form 1947 MHz to 1964 MHz is obtaine dby an external varactor diode connected to the gate with a tuning voltage from 0 V to 6V.

• 한국정보디스플레이학회:학술대회논문집
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• 2008.10a
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• pp.1503-1506
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• 2008

A novel white-LED (light emitting diode) backlight system for 46"LCD TVs which involves the current controlled X-Y channel driving method is proposed in this paper. There are two problems related to the LED current in the conventional X-Y channel driving driven by a constant voltage source. To solve these problems, a real time current sensing system is applied to the conventional one and the time-division current sensing method is employed.

• Journal of the Korean Institute of Telematics and Electronics
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• v.7 no.2
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• pp.33-42
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• 1970

This report is concerned with the fahrication with the falricationof silicon VVC diode by the double diffusion planer technique. At first, some design charts for VVC diode were derived by considering the voltage-capacitance relations, the critical field intensity at the metallurgical junction, and the cut-off frequency of the diode. These charts enables the fabrication engineers to design VVC diode easily without going into the sophisticated design theory. We started with a 2.5 ohm-cm n-type epitaxial silicon wafer. The phosphorous was diffused by POCl3 impurity source. Then boron diffusion followed make hyperabrupt p-n junction by BN source. The maximum to minimum capacitance ratio of the diode as a tuning diode for a TV tuner made in these experiments was 4:1. Measured electrical characteristics of the sample diodes showed in good agreement with the theoretical expectations. Slicing and polishing technique of the silicon wafer and diffusion technique of the impurity atoms, which were employed in our study, are also stated briefly in this report.

• JSTS:Journal of Semiconductor Technology and Science
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• v.14 no.1
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• pp.1-7
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• 2014

A bidirectional transient voltage suppression (TVS) diode consisting of specially designed $p^--n^{{+}+}-p^-$ multi-junctions was developed using low temperature (LT) epitaxy and fabrication processes. Its electrostatic discharge (ESD) performance was investigated using I-V, C-V, and various ESD tests including the human body model (HBM), machine model (MM) and IEC 61000-4-2 (IEC) analysis. The symmetrical structure with very sharp and uniform bidirectional multi-junctions yields good symmetrical I-V behavior over a wide range of operating temperature of 300 K-450 K and low capacitance as 6.9 pF at 1 MHz. In addition, a very thin and heavily doped $n^{{+}+}$ layer enabled I-V curves steep rise after breakdown without snapback phenomenon, then resulted in small dynamic resistance as $0.2{\Omega}$, and leakage current completely suppressed down to pA. Manufactured bidirectional TVS diodes were capable of withstanding ${\pm}4.0$ kV of MM and ${\pm}14$ kV of IEC, and exceeding ${\pm}8$ kV of HBM, while maintaining reliable I-V characteristics. Such an excellent ESD performance of low capacitance and dynamic resistance is attributed to the abruptness and very unique profiles designed very precisely in $p^--n^{{+}+}-p^-$ multi-junctions.

• Proceedings of the KIEE Conference
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• 2001.07c
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• pp.1732-1734
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• 2001

The purpose of this experiment was to develope Triggered Vacuum Switch(TVS) and to improve understanding of the high current vacuum arc phenomena in the TVS. The TVS has an array of rods of alternate polarity in which a fixed gap spacing is maintained between the rods. The cross section of each rod has trapezoidal shape. Breakdown of the TVS produced high current vacuum arc plasma. A spectroscopic measurement was performed over 20 kA peak current in the center of electrodes, in the vicinity of cathode, and outside electrodes. The electrode material tested was Fe. Measured Fe spectrum range was from 200 nm to 900 nm. Measurement result showed that over 90 percent of the charge states were FeII and the others were FeI and FeIII. The electron temperature was determined from the relative line intensity ratio methode of FeII system by assuming the local thermal equilibrium(LTE). The electron temperature at the center of electrodes was measured as 1.5 eV at 26 kA peak current. The electron temperature varied with its peak current. Intensity of spectrums is the highest in the vicinity of the cathode. Further we will also present study result of the diode phenomena in the TVS.

• 한국정보디스플레이학회:학술대회논문집
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• 2004.08a
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• pp.943-946
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• 2004

We report the laser scanning display as an emerging technology. We show demonstration system of laser TV, Video image is made by using a high speed MEMS scanning mirror and a direct-modulated red diode laser. We designed and fabricated MEMS scanning mirror. The first demonstration system showed a NTSC-resolution video image with the image size of 5 inches. The successful development of compact laser TV will open a new area of home application of the laser light.

• Proceedings of the KIPE Conference
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• 2008.06a
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• pp.271-273
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• 2008

A novel white-LED (light emitting diode) backlight system for 46"LCD TVs which involves the average current controlled X-Y channel driving method is proposed, which is composed of 1 converter and row and column channel switches. In the conventional X-Y channel driving driven with a constant voltage source, the driving current of LED increases because the threshold voltage of LED decreases when LED temperature goes up. To maintain the luminance of backlight constant, the average current controlled X-Y channel driving will be employed. Finally the results are confirmed by experimental results.

• 한국정보디스플레이학회:학술대회논문집
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• 2008.10a
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• pp.1163-1167
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• 2008

Since Samsung SDI and Sony started mass production of AM-OLED display for mobile/TV applications, OLED technology has emerged as leading candidate among the many technologies under development for next generation Flat panel displays. P-OLED (Polymer Organic Lighting Emitting Diode) technology, a class of OLED, is gathering momentum towards commercialization. P-OLED technology has made tremendous progress in terms of display performance (including life time, efficiency and color gamut) and in the maturity of ink jet printing process and equipment. In order to get into the mobile/TV application market successfully, P-OLED display technology must meet the following display makers' requirements: (1) P-OLED Display Performance in terms of lifetime, efficiency, and color coordinates, (2) Low Cost Manufacturing Technology such as "Solution Processable Printing Technology". P-OLED technology has already overcome many of the hurdles to mass manufacturing. In this paper, the latest developments in ink jet printing technology, including P-OLED material performance, is discussed.

• 한국정보디스플레이학회:학술대회논문집
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• 2008.10a
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• pp.119-122
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• 2008

In this paper, we describe the current status and issues of the oxide thin-film transistors (OTFTs), which attract much attention as an emerging new backplane technology replacing conventional silicon-based TFTs technologies. First, the unique benefits of OTFTs will be presented as a backplane for large-sized AMOLED including note-book PC, second TV and HD-TV. And then, the state-of-the-art transistor performance and uniformity characteristics of OTFTs will be highlighted. The obtained a-IGZO TFTs exhibited the field-effect mobility of $18\;cm^2/Vs$, threshold voltage of 1.8 V, on/off ratio of $10^9$, and subthreshold gate swing of 0.28 V/decade. In addition, the world largest-sized 12.1-inch WXGA active-matrix organic light emitting diode (AMOLED) display is demonstrated using indium-gallium-zinc oxide (IGZO) TFTs.

• 한국정보디스플레이학회:학술대회논문집
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• 2007.08a
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• pp.1001-1004
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• 2007

This paper proposes a novel RGB-LED (light emitting diode) backlight system, for 32" LCD TVs, accompanied by a new X-Y Channel driving method in which its row and column switches control the individual division screen. This proposed driving method is able to produce division driving effects such as image improvement and reduced power consumption. Not only that, the number of driver needed in this method, that is 3 power supplies with 3*(m+n) switches, is much fewer than that of cluster driving method, that is 3*(m*n) driver.