Abstract: Provided are a composition for an oxide semiconductor thin film, a field effect transistor using the same and a method of fabricating the field effect transistor. The composition includes an aluminum oxide, a zinc oxide, an indium oxide and a tin oxide. The thin film formed of the composition is in amorphous phase. The field effect transistor having an active layer formed of the composition can have an improved electrical characteristic and be fabricated by a low temperature process.

Abstract: A composition for an oxide semiconductor thin film, a field effect transistor (FET) using the composition, and a method of fabricating the FET are provided. The composition includes an aluminum oxide, a zinc oxide, and a tin oxide. The thin film formed of the composition remains in amorphous phase at a temperature of 400° C or less. The FET using an active layer formed of the composition has improved electrical characteristics and can be fabricated using a low-temperature process without expensive raw materials, such as In and Ga.

Abstract: Provided is an LC resonance voltage-controlled oscillator (VCO) used for a multi-band multi-mode wireless transceiver. In order to generate a multi-band frequency, a capacitor bank and a switchable inductor are included in the LC resonance voltage-controlled oscillator. The LC resonance voltage-controlled oscillator employs an adjustable emitter-degeneration negative resistance cell in place of tail current sources in order to compensate for non-uniform oscillation amplitude caused by the capacitor bank and prevent the degradation of a phase noise due to the tail current sources.

Abstract: Provided are bipolar transistor, BiCMOS device and method of fabricating thereof, in which an existing sub-collector disposed beneath a collector of a SiGe HBT is removed and a collector plug disposed at a lateral side of the collector is approached to a base when fabricating a Si-based very high-speed device, whereby it is possible to fabricate the SiGe HBT and an SOI CMOS on a single substrate, reduce the size of the device and the number of masks to be used, and implement the device of high density, low power consumption, and wideband performance.

Abstract: Provided is a wristwatch-type mobile device. The wristwatch-type mobile device includes a wristwatch device, a mobile device, and an I/O device. The I/O device is selectively used as one of an output device of the wristwatch device and an I/O device of the mobile device.

Abstract: Provided are an NMOS device, a PMOS device and a SiGe HBT device which are implemented on an SOI substrate and a method of fabricating the same. In manufacturing a Si-based high speed device, a SiGe HBT and a CMOS are mounted on a single SOI substrate. In particular, a source and a drain of the CMOS are formed of SiGe and metal, and thus leakage current is prevented and low power consumption is achieved. Also, heat generation in a chip is suppressed, and a wide operation range may be obtained even at a low voltage.

Abstract: A narrowband microstrip type bandpass filter adapted for a home network, telematics, an intelligent traffic system, and a satellite Internet, includes: an input terminal for receiving a predetermined signal; an output terminal for outputting a selection signal in a characteristic band; a first resonator electrically coupled with at least a portion of the input terminal; a second resonator electrically coupled with at least a portion of the first resonator; and a third resonator electrically coupled with at least a portion of the output terminal and the second resonator. A magnetic coupling is provided using a cross coupling gap or a cross coupling line between non-adjacent resonators, so that a pattern can be simplified by optimizing the design and the manufacturing process to provide low-cost millimeter-wave parts. The manufacturing cost can be reduced by miniaturizing the parts, and the mass production can be readily realized.

Abstract: Provided are an NMOS device, a PMOS device and a SiGe HBT device which are implemented on an SOI substrate and a method of fabricating the same. In manufacturing a Si-based high speed device, a SiGe HBT and a CMOS are mounted on a single SOI substrate. In particular, a source and a drain of the CMOS are formed of SiGe and metal, and thus leakage current is prevented and low power consumption is achieved. Also, heat generation in a chip is suppressed, and a wide operation range may be obtained even at a low voltage.

Abstract: Provided is a millimeter-wave band frequency optical oscillator that can be used as an oscillation frequency signal source for a millimeter-wave forwarded to wireless subscribers from a base station of a millimeter-wave wireless subscriber communication system for a next generation (e.g., fifth generation) ultra-high speed wireless internet service. A pair of an optical fiber amplifier and an optical fiber grating mirror is connected to each of input/output ports of a loop mirror in parallel, so that a dual mode laser resonator is formed which can make simultaneous oscillation in two laser modes suitable for each wavelength. Accordingly, it is possible to obtain a light source that is modulated to a ultra-high frequency (over 60 GHz) by a beat phenomenon between the two laser modes.

Abstract: Provided is a method of fabricating an optoelectronic integrated circuit chip. In particular, a method of fabricating an optoelectronic integrated circuit chip is provided, in which an optical absorption layer of a wave-guide type optical detector is grown to be thicker than a collector layer of a hetero-junction bipolar transistor by using a selective area growth by metal organic chemical vapor deposition (MOCVD) method, and the wave-guide type optical detector and the hetero-junction bipolar transistor are integrated as a single chip on a semi-insulated InP substrate, thereby readily realizing the wave-guide type optical detector improved in quantum efficiency and having the ultra-high speed characteristics.

Abstract: The present invention relates to a millimeter wave frequency band optical oscillator used for an oscillating frequency signal source of millimeter waves transmitted from a repeater to a wireless subscriber in a millimeter wave wireless subscriber communication system for a next-generation (i.e., 5th generation or less) very high speed wireless internet service, wherein a loop mirror and a pair of optical fiber grating mirrors are used. A wavelength fixed type and a wavelength tunable type optical fiber grating mirrors are connected in a serial manner to constitute a dual laser mode resonator capable of simultaneously oscillating two laser modes, which are appropriate to each wavelength. Therefore, it is possible to obtain a laser light source capable of an extremely high frequency (60 GHz or more) modulation by using beat phenomena between two laser modes.

Abstract: A microwave power amplifier comprising a drive amplifying stage includes power elements, gate and drain bias circuits of the power elements, a RC parallel circuit connected between input port and gates of said power elements, a shunt resistor connected between ground terminal and said gates of power elements, and a negative feedback circuit connected in series with resistors and capacitors and in parallel with the power elements. An interstage matching circuit is connected in series with the drive amplifying stage; and a power amplifying stage including power elements connected in parallel with a power divider and a power coupler, gate and drain bias circuits of said power elements, a RC parallel circuit connected between the gates of power elements and the interstage matching circuit, and a shunt resistor connected between a ground and the gates of power elements.

Abstract: Provided is a method of fabricating an optoelectronic integrated circuit chip. In particular, a method of fabricating an optoelectronic integrated circuit chip is provided, in which an optical absorption layer of a wave-guide type optical detector is grown to be thicker than a collector layer of a hetero-junction bipolar transistor by using a selective area growth by metal organic chemical vapor deposition (MOCVD) method, and the wave-guide type optical detector and the hetero-junction bipolar transistor are integrated as a single chip on a semi-insulated InP substrate, thereby readily realizing the wave-guide type optical detector improved in quantum efficiency and having the ultra-high speed characteristics.

Abstract: There is provided a millimeter wave band frequency optical oscillator predicted to be used as a millimeter wave oscillating frequency signal source in a base station of a millimeter wave wireless transmission system. The optical oscillator has a double resonator structure in which a pair of wavelength tunable fiber grating mirrors are inserted into a unilateral fiber-ring laser resonator in order to internally and additionally form a linear laser resonator. The double resonator structure composed of the two stable laser resonators can oscillate laser of two modes. Due to a beat phenomenon occurring between the two modes, received laser is modulated to an ultra-speed frequency of 60 GHz or greater. A variation in the gain within a resonator is induced by a polarization controller using the dependency of laser modes upon polarization. A modulation frequency is consecutively changed from 60 GHz to 80 GHz by controlling the wavelength of light reflected by the fiber grating mirrors.

Abstract: A microstrip cross coupling bandpass filter includes an input port, an input resonator, an output port, and an output resonator. The input port and the input resonator are electric-coupled, and the output port and the output resonator are electric-coupled. A cross coupling gap corresponding to the distance between the input and output resonators forms magnetic coupling. The bandpass filter further includes a cross coupling line electric-coupled with the input and output ports. The cross coupling gap generates an attenuation pole on the high side of a passband. The attenuation frequency of the attenuation pole can be varied with the distance of the cross coupling gap. The cross coupling line generates an attenuation pole on the high and low sides of the passband.

Abstract: The present invention relates to a cathode for use in a field emission device. In a triode-type cathode for use in an electron emission device being a core component constituting a field emission device, the present invention includes forming a catalytic layer at the sidewall of a gate hole and then growing an emitter in the catalytic layer, thus uniformly distributing an electric field generated by a voltage applied to a gate electrode over the emitter. Therefore, the present invention can improve the brightness contrast at a low anode voltage and also can control electrons emitted from the emitter only with the gate voltage.

Abstract: A microwave power amplifier comprising a drive amplifying stage includes power elements, gate and drain bias circuits of the power elements, a RC parallel circuit connected between input port and gates of said power elements, a shunt resistor connected between ground terminal and said gates of power elements, and a negative feedback circuit connected in series with resistors and capacitors and in parallel with the power elements. An interstage matching circuit is connected in series with the drive amplifying stage; and a power amplifying stage including power elements connected in parallel with a power divider and a power coupler, gate and drain bias circuits of said power elements, a RC parallel circuit connected between the gates of power elements and the interstage matching circuit, and a shunt resistor connected between a ground and the gates of power elements.

Abstract: The present invention relates to a field emission device including a silicon substrate having an emitter electrode formed in a surface portion thereof, an insulating layer formed on the emitter electrode and having a nano hole to expose the emitter electrode. An emitter is formed on the emitter electrode exposed through the nano hole. A gate electrode is formed on the insulating layer. The present invention can reduce the driving voltage and thus lower the power consumption.

Abstract: There is provided a millimeter wave band frequency optical oscillator predicted to be used as a millimeter wave oscillating frequency signal source in a base station of a millimeter wave wireless transmission system. The optical oscillator has a double resonator structure in which a pair of wavelength tunable fiber grating mirrors are inserted into a unilateral fiber-ring laser resonator in order to internally and additionally form a linear laser resonator. The double resonator structure composed of the two stable laser resonators can oscillate laser of two modes. Due to a beat phenomenon occurring between the two modes, received laser is modulated to an ultra-speed frequency of 60 GHz or greater. A variation in the gain within a resonator is induced by a polarization controller using the dependency of laser modes upon polarization. A modulation frequency is consecutively changed from 60 GHz to 80 GHz by controlling the wavelength of light reflected by the fiber grating mirrors.

Abstract: The present invention relates to a field emission device and a method of fabricating the same. The method includes forming a hole having a nanometer size using silicon semiconductor process and then forming an emitter within the hole to form a field emission device. Therefore, the present invention can reduce the driving voltage and thus lower the power consumption.