Abstract: A delay locked loop (DLL) includes a delay-locking unit configured to generate first and second delay clocks corresponding to first and second clock edges of a reference clock for achieving a delay-locking; a phase detection unit configured to detect a phase difference between the first and second delay clocks to output a weight selection signal; a weight storage unit configured to store the weight selection signal obtained during a predetermined period from a point of time when the first and second delay clocks are delay locked; and a phase mixing unit configured to mix phases of the first and second delay clocks to output a DLL clock by applying a weight corresponding to the stored weight selection signal in the weight storage unit.

Abstract: A method of fabricating a semiconductor device includes forming a buffer insulating film over a semiconductor substrate including a conductive pattern. The buffer insulating film is etched using a storage node mask to form a buffer insulating pattern exposing the conductive pattern. The buffer insulating pattern defines a region wider than a storage node region. An etch stop film is formed over the conductive pattern and the buffer insulating pattern. An interlayer insulating film is formed over the etch stop film. The interlayer insulating film is etched using the storage node mask to expose the etch stop film. The exposed etch stop film is etched to form the storage node region exposing conductive pattern. A lower storage node is formed over the storage node region.

Abstract: A ZQ calibration circuit performs a ZQ calibration additionally in an initial operation of a semiconductor memory device. The ZQ calibration controller of the ZQ calibration circuit includes a first signal generator, a second signal generator, and a control unit. The first signal generator generates a pre-calibration signal during an initialization of the semiconductor memory device. The second signal generator generates ZQ calibration signals in response to a ZQ calibration command. The control unit outputs signals to control a ZQ calibration in response to the pre-calibration signal and the ZQ calibration signals.

Abstract: A parallel resistor circuit that can reduce an error of a resistance value, an on-die termination having the same, and a semiconductor device having the on-die termination device. The semiconductor memory device includes a calibration circuit configured to pull up or pull down a predetermined node and compare a voltage of the predetermined node with a reference voltage to generate calibration codes, by using parallel resistor units that are turned on or off in response to the calibration codes. An output driver is configured to terminate a data output node to a pull-up or pull-down level to output data, by using the parallel resistor units. At least one of the parallel resistor units having at least two resistivities includes resistors with different resistivities connected to each other in parallel.

Abstract: A delay locked loop (DLL) of a semiconductor device includes: a first delay line for delaying a first clock signal in synchronization with a first edge of an external clock signal to output a first delayed clock signal; a second delay line for delaying a second clock signal in synchronization with a second edge of the external clock to output a second delayed clock signal; a duty cycle corrector (DCC) for mixing phases of the first and second delayed clock signals to output a DLL clock signal with a corrected duty cycle; and a DCC controller for disabling the duty cycle corrector in a section during which a phase difference between the first and second delayed clock signals is greater than a preset time after a delay locking.

Abstract: A semiconductor memory device is capable of maintaining a predetermined back-bias voltage level regardless of operation modes of the semiconductor memory device, by generating a back-bias voltage with driving force changed according to the operation modes. The semiconductor memory device includes an active pumping control signal generating unit for generating an active pumping control signal in response to a plurality of active signals, a voltage detecting unit for detecting a voltage level of a back-bias voltage terminal to output a detection signal, an oscillator for generating an oscillation signal oscillating at a predetermined frequency in response to the detection signal, and a charge pumping unit for performing a charge pumping operation in response to the oscillation signal by controlling a force of driving the back-bias voltage terminal in response to the active pumping control signal.

Abstract: A semiconductor device with an asymmetric transistor and a method for fabricating the same are provided. The semiconductor device includes: a substrate having a plurality of first active regions, at least one second active region, and a plurality of device isolation regions; gate patterns formed in a step structure over a border region between individual first active regions and second active region, wherein one side of the individual gate pattern is formed over a portion of the individual first active region, and the other side of the individual gate pattern is formed over a portion of the second active region; spacers formed on lateral walls of the gate patterns; first cell junction regions formed in the first active regions, for connecting to storage nodes; and a second cell junction region formed in the second active region, for connecting to a bit line.

Abstract: An internal voltage discharge circuit includes a differential comparator for differentially comparing a reference voltage with a feedback voltage to generate a discharge control voltage, a level detector for detecting a level of external power supply voltage and a discharge unit for adjusting an amount of discharge of an internal voltage based on the level signal detected by the level detector and the discharge control voltage from the differential comparator.

Abstract: An internal voltage generating circuit of a semiconductor device includes a first voltage driver configured to pull up an internal voltage terminal during a period where a level of the internal voltage terminal is lower than a target level, and a second voltage driver configured to pull up the internal voltage terminal during a predefined time in each period corresponding to a frequency of an external clock.

Abstract: A semiconductor device is capable of stably maintaining a voltage level of a shield line, even when a voltage level of an adjacent line is varied. The semiconductor device includes normal lines arranged for transfer of signals, a shield line arranged adjacently to the normal lines, a level shifting circuit for receiving an input signal swinging between a power supply voltage level and a ground voltage level, and shifting the input signal to an output signal swing between the power supply voltage level and a low voltage level lower than the ground voltage level by a predetermined level to output a shifted signal via the shield line, and a signal input unit for transferring the signal provided via the shield line to an output node.

Abstract: A clock generating circuit, including a pulse generating unit to generate a plurality of pulse signals based on a reference clock, the pulse signals each having the same period, a phase difference between the adjacent pulse signals being a first phase difference; and a multi-phase clock generating unit to generate a plurality of multi-phase clocks, a phase difference between the adjacent multi-phase clocks being equal to a second phase difference between pulse signals of a pulse signal pair, based on a plurality of unit-phase clock generating units receiving the pulse signal pairs.

Abstract: Calibration circuit, semiconductor memory device including the same, and operation method of the calibration circuit includes a calibration unit configured to generate a calibration code for controlling a termination resistance value, a calibration control unit configured to count a clock and allow the calibration unit to be enabled during a predetermined clock and a clock control unit configured to selectively supply the clock to the calibration control unit according to an operation mode of a semiconductor device employing the calibration circuit.

Abstract: An output driver for use in a semiconductor device includes a first pre-drive unit, a second pre-drive unit, and a main drive unit. The first pre-drive unit generates a pull-up drive control signal based on a data signal. The pull-up drive control signal swings between a power supply voltage level and a low voltage level. The data signal swings between the power supply voltage level and a ground voltage level. The second pre-drive unit generates a pull-down drive control signal based on the data signal. The pull-down drive control signal swings between a high voltage level and the ground voltage level. The main drive unit performs pull-up/down drive operations to an output terminal in response to the pull-up/down drive control signals, respectively. Herein, the high voltage level is higher than the power supply voltage level and the low voltage level is lower than the ground voltage level.

Abstract: A method for fabricating a capacitor includes: forming a storage node contact plug over a substrate; forming an insulation layer having an opening exposing a surface of the storage node contact plug over the storage contact plug; forming a conductive layer for a storage node over the insulation layer and the exposed surface of the storage node contact plug through two steps performed at different temperatures; performing an isolation process to isolate parts of the conductive layer; and sequentially forming a dielectric layer and a plate electrode over the isolated conductive layer.

Abstract: An XOR logic circuit includes a first transfer unit configured to transfer a logic high level data to an output terminal in response to data applied to first and second input terminals; a multiplexing unit configured to output a power voltage or a ground voltage in response to the data applied to the first and second input terminals; and a second transfer unit configured to transfer a logic low level data to the output terminal in response to an output signal of the multiplexing unit and the data applied to the first and second input terminals.

Abstract: A method for fabricating a semiconductor device includes forming an interlayer insulating film over a semiconductor substrate. The interlayer insulating film is selectively etched to form a hole defining a storage node region. A lower electrode is formed in the hole. A support layer is formed over the lower electrode. The support layer fills an upper part of the hole and exposes the interlayer insulating film. A dip-out process is performed to remove the interlayer insulating film. The supporting layer is removed to expose the lower electrode. A dielectric film is formed over the semiconductor substrate including the lower electrode. A plate electrode is formed over the semiconductor substrate to fill the dielectric film and the lower electrode.

Abstract: A method for fabricating a semiconductor device with a bulb-shaped recess gate pattern is provided. The method includes forming a plurality of oxide layers over a substrate; forming a silicon layer to cover the oxide layers; forming a mask over the silicon layer; etching the silicon layer using the mask as an etch mask to form a plurality of first recesses to expose the oxide layers; etching the oxide layers to form a plurality of second recesses; and forming a plurality of gate patterns at least partially buried into the first recesses and the second recesses.

Abstract: A DLL circuit and a synchronous memory device perform stable operation in a power down mode although the entry and exit into/from the power down mode is repeated rapidly. The synchronous memory device operates in a normal mode and a power down mode. A delay locked loop (DLL) generates a DLL clock having frozen locking information when exiting the power down mode. A controller precludes phase update operation of the DLL when a predetermined time passes after entering the power down mode to thereby obtain a time margin for a phase update operation undertaken in the normal mode.

Abstract: A semiconductor memory device including a bit-line sense amplifier is not affected by variation in manufacturing process and has a stable driving scheme. The semiconductor memory device includes: a unit memory cell for storing a data; a sense amplification unit including a bit-line sense amplifier (BLSA) for sensing and amplifying a voltage difference of a bit-line pair receiving the data of the unit memory cell; a variation detection unit for detecting a variation of a manufacturing process to output a detecting signal; and a sense amplifier controlling unit for controlling the BLSA to be activated after a predetermined time from an activation of unit memory cell in response to the detecting signal.

Abstract: A semiconductor memory device includes: a variable delay for delaying a delay locked loop (DLL) clock by a predetermined delay time to output a delayed DLL clock; an output driver for outputting data and data strobe signal in response to the delayed DLL clock; and a calibration controller for controlling the predetermined delay time of the variable delay in response to output AC parameters.