Abstract: A semiconductor device including a first interlayer insulating film; a conductive pattern in the first interlayer insulating film; a resistance pattern on the conductive pattern; an upper etching stopper film spaced apart from the resistance pattern, extending in parallel with a top surface of the resistance pattern, and including a first metal; a lower etching stopper film on the conductive pattern, extending in parallel with a top surface of the first interlayer insulating film, and including a second metal; and a second interlayer insulating film on the upper etching stopper film and the lower etching stopper film, wherein a distance from a top surface of the second interlayer insulating film to a top surface of the upper etching stopper film is smaller than a distance from the top surface of the second interlayer insulating film to a top surface of the lower etching stopper film.

Abstract: The present invention relates to a polyester resin. The polyester resin is useful for bottles, sheets, multilayer sheets, stretched films and fiber applications due to excellent heat resistance and transparency, and in particular, the polyester resin has little deterioration of physical properties such as yellowing, etc., during processing. A process for making the polyester resin includes an esterification reaction between a dicarboxylic acid that includes terephthalic acid and a diol that includes isosorbide in the presence of a catalyst, followed by a polycondensation reaction on a product of the esterification reaction. In some embodiments, an initial mixing ratio of the dicarboxylic acid and the diol is between 1:1.02 and 1:1.04.

Abstract: An antenna device according to an embodiment includes a dielectric layer, an antenna unit disposed on a top surface of the dielectric layer and including a radiator, and a dummy mesh pattern disposed around the antenna unit and spaced apart from the antenna unit. The dummy mesh pattern includes conductive lines and segmented regions at which the conductive lines are cut. The segmented regions formed in three parallel conductive lines neighboring each other among the conductive lines are not disposed together on an imaginary straight line extending perpendicularly to an extending direction of the conductive lines. A visual recognition of the antenna unit is prevented.

Abstract: An antenna device according to embodiments includes a dielectric layer having a central portion and a peripheral portion, a first antenna unit disposed on a top surface of the dielectric layer and including a first radiator providing a vertical radiation from the top surface of the dielectric layer, and a second antenna unit spaced apart from the first antenna unit on a plan view and comprising a second radiator providing an omni-directional radiation.

Abstract: An antenna structure according to an embodiment includes a radiator including a plurality of radiating portions integrally connected to each other, the plurality of radiating portions having sequentially reducing widths, a transmission line electrically connected to the radiator, and a pair of ground patterns facing each other with the transmission line interposed therebetween to be physically spaced apart from the radiator and the transmission line. A broadband antenna structure capable of providing a multi-band radiation can be implemented.

Abstract: An antenna structure according to an embodiment of the present disclosure includes a transmission line, and a radiator connected to the transmission line, the radiator having a linear perimeter region and a plurality of curved perimeter regions separated by the linear perimeter region, wherein an outermost portion of the radiator from the transmission line in a planar view has any one of the curved peripheral regions. A broadband antenna structure covering low frequency and high frequency bands is provided.

Abstract: Circuit for operating a microwave oven including a DC voltage source, a switching part having at least two switching devices electrically connected to the DC voltage source for switching a voltage from the DC voltage source, controlling part for controlling the switching part, a magnetron for generating a microwave, and a converting part for converting the voltage from the DC voltage source to a voltage for operating the magnetron by switching of the switching part, thereby permitting operation of the microwave oven by using a car battery.

Abstract: An inverter circuit of a microwave oven employs a technique which decreases the unit manufacturing cost of production and controls an output of a magnetron correctly. The invert circuit includes a micom outputting a reference voltage preset by a user; an input current detector converting a current provided from the power source to a voltage level; and comparator comparing an output signal of the input current detector with the reference voltage; an integrator increasing or decreasing a level of an output signal for the comparator a trigger circuit connected to the high voltage transformer, and generating a trigger signal; and a PWM controller receiving an output signal of the integrator and an output al of the trigger circuit, for controlling drive of the magnetron.

Abstract: A variable-frequency inverter microwave oven and a method for controlling the same. The inverter microwave oven comprises a magnetron for generating electromagnetic waves, a direct current (DC) voltage generator for rectifying and smoothing a commercial alternating current (AC) voltage, which is an inverter drive voltage, to generate a DC voltage, and a switching device for performing a switching operation based on the DC voltage from the DC voltage generator to generate an AC voltage for the driving of the magnetron. The switching device includes a plurality of switches turned on/off in response to the DC voltage from the DC voltage generator.

Abstract: An inverter circuit of a microwave oven is disclosed, in which it is possible to decrease the unit manufacturing cost of production, and to control an output of a magnetron correctly. The inverter circuit of the microwave oven according to the present invention is provided with a micom outputting a reference voltage preset by a user; an input current detector converting a current provided from the power source to a voltage level; a comparator comparing an output signal of the input current detector with the reference voltage; an integrator increasing or decreasing a level of an output signal of the comparator; a trigger circuit connected to the high voltage transformer, and generating a trigger signal; and a PWM controller receiving an output signal of the integrator and an output signal of the trigger circuit, for controlling drive of the magnetron.

Abstract: A variable-frequency inverter microwave oven and a method for controlling the same. The inverter microwave oven comprises a magnetron for generating electromagnetic waves, a direct current (DC) voltage generator for rectifying and smoothing a commercial alternating current (AC) voltage, which is an inverter drive voltage, to generate a DC voltage, and a switching device for performing a switching operation based on the DC voltage from the DC voltage generator to generate an AC voltage for the driving of the magnetron. The switching device includes a plurality of switches turned on/off in response to the DC voltage from the DC voltage generator.

Abstract: Circuit for operating a microwave oven including a DC voltage source, a switching part having at least two switching devices electrically connected to the DC voltage source for switching a voltage from the DC voltage source, controlling part for controlling the switching part, a magnetron for generating a microwave and a converting part for converting the voltage from the DC voltage source to a voltage for operating the magnetron by switching of the switching part, thereby permitting operation of the microwave oven by using a car battery.

Abstract: A silicon carbide electric heating element includes: a terminal part to which power is supplied; a heat generation part connected to the terminal part and generating heat; and a cooling part formed at the terminal part to cool the terminal part. Since the terminal part is not heated, the electric wire can be directly connected for use to the terminal part without an additional connection member.

Abstract: The present invention relates to a microwave oven including a cavity having a certain area for cooking comprising a flow path formed between a main body and the cavity so as to be connected from a side of the cavity to the upper surface of the cavity, a heater installed on the side of the flow path corresponding to the outer upper surface of the cavity for emitting heat, a discharge hole installed on the upper surface of the cavity corresponding to the lower portion of the heater for discharging the heat of the heater into the cavity, an inlet installed on the lower portion of the side wall of the cavity for making the air inside of the cavity flow in the flow channel, and a circulating fan installed on a certain portion of the flow channel for circulating the air inside of the cavity flown through the inlet to the heater.

Abstract: A uniform heating structure for a microwave oven is provided. The structure of the invention includes: a magnetron for generating microwaves, a wave guide for guiding the microwaves generated by the magnetron, a pair of openings for radiating the microwaves guided by the wave guide in the form of circular polarized waves, and a cavity which is shaped in a polyhedron more than a rectangular and in which more than one interior walls constructing the polyhedron slope at a predetermined angle (&thgr;1) excepting a right angle with respect to a neighboring interior wall. With this structure, the microwaves generated by the magnetron are reflected to be delivered to food through a sloping interior wall of the cavity while being radiated to the cavity through the wave guide and the openings, thus ensuring a uniform distribution of the microwaves throughout the food and making the food uniformly cooked.

Abstract: A uniform heating structure for a microwave oven is provided. The structure of the invention includes: a magnetron for generating microwaves, a wave guide for guiding the microwaves generated by the magnetron, a pair of openings for radiating the microwaves guided by the wave guide in the form of circular polarized waves, and a cavity which is shaped in a polyhedron more than a rectangular and in which more than one interior walls constructing the polyhedron slope at a predetermined angle(&thgr;1) excepting a right angle with respect to a neighboring interior wall. With this structure, the microwaves generated by the magnetron are reflected to be delivered to food through a sloping interior wall of the cavity while being radiated to the cavity through the wave guide and the openings, thus ensuring a uniform distribution of the microwaves throughout the food and making the food uniformly cooked.

Abstract: The present invention relates to a device capable of cooking food products in a short time so as to concentrate the emitted light on the food product using a lamp emitting light in an infrared region. More particularly, it is capable of cooking the food product in a short time by concentrating light in the visible light region within a wavelength range of more than 1.35 &mgr;m on the food product using a luminous unit for emitting light in the infrared light region and a reflecting plate for concentrating the emitted light in the infrared light region.

Abstract: A halogen heater control apparatus of a microwave oven and a method thereof, comprises a plurality of halogen heaters which are connected to a utility AC power source, and a halogen heater switching unit. The halogen heater and incrementally alters infrared wavelengths from the halogen heater, and a microcomputer controls the operation of the halogen heater switching unit. The present invention is capable of optimum foodstuff heating and cooking by incrementally altering and controlling the infrared wavelengths from the halogen heater by controlling the utility AC power source duty cycle to the halogen heater in accordance with control signals generated by the microcomputer.

Abstract: The induction cooking apparatus includes an input filter for filtering supplied power, a first inverter module having a first working coil, a second inverter module having a second working coil, and a common switching section. The common switching section and the first and second inverter modules are connected in series with the input filter, and the first and second inverter modules operate cooperatively with the common switching section to energize the first and second working coils.