Abstract: Disclosed is a method of bonding upper and lower substrates for manufacturing a plastic micro chip comprising the upper substrate, the lower substrate and a sample filling space having a predetermined height for filling a sample between the upper and lower substrates. According to the method, the upper and lower substrates are bonded by introducing an organic solvent between the upper and lower substrates. In addition, the invention provides a method of manufacturing a micro chip using the method and a micro chip manufactured according to the method. According to the invention, it is possible to easily and precisely bond the upper and lower substrates of the plastic micro chip.

Abstract: The present invention relates to a directional coupler, in particular, to a capacitance compensation type directional coupler comprising a signal line for transmitting signals. A coupling line is formed apart from and parallel to the signal line, with its first end transmitting the extracted power and its second end terminated. At least one conductive line, electrically connected to the coupling line, is extended from the coupling line across the signal line, apart from and perpendicularly overlapping with the signal line. The present invention compensates capacitance between the signal line and the coupling line by forming capacitance in areas where the conductive line and the signal line overlapping each other perpendicularly.

Abstract: Disclosed herein are a directional coupler which is implemented with strip lines for signal coupling and inter-digital capacitors for phase compensation, and a dual-band transmitter using the same. The directional coupler includes a first transmission device, a first directional coupling device for coupling a part of a signal from the first transmission device, a first inter-digital capacitor connected between the first transmission device and the first directional coupling device, a second transmission device, a second directional coupling device for coupling a part of a signal from the second transmission device, and a second inter-digital capacitor connected between the second transmission device and the second directional coupling device.

Abstract: The invention provides a dual band transmitter available for a mobile communication terminal such as mobile phone, in which a first RF amplifier 111 amplifies the power of a high band signal BS1 at a first amplification factor that is determined according to a first bias voltage. A second RF amplifier 121 amplifies the power of a low band signal BS2 at a second amplification factor determined according to a second bias voltage. A first coupling capacitor C11 couples an output signal from the first RF amplifier 111. A second coupling capacitor C21 couples an output signal from the second RF amplifier 121. A filtering coupler 140 has a high pass filter FT1 for a first coupled signal from the first coupling capacitor C11 and a low pass filter FT2 for a second coupled signal from the second coupling capacitor C21.