Abstract: A two-step analog-digital converting circuit includes a comparator, an upper bit counter and a pulse residue conversion unit. The comparator is configured to compare a ramp signal and an input signal, and to output a resulting comparative signal. The upper bit counter is configured to receive the comparative signal and a clock signal, and to output upper bit values corresponding to a first time interval between a generation time point of the ramp signal and a first edge of the clock signal, the first edge of the clock signal immediately preceding a state transition time point of the comparative signal. The pulse residue conversion unit is configured to receive the comparative signal and the clock signal, and to output lower bit values corresponding to a second time interval between the first edge of the clock signal and the state transition time point of the comparative signal.

Abstract: A semiconductor device includes a channel region extending in a vertical direction perpendicular to a substrate and having a nitrogen concentration distribution, a plurality of gate electrodes arranged on a side wall of the channel region and separated from each other in a vertical direction, and a gate dielectric layer disposed between the channel region and the gate electrodes. The nitrogen concentration distribution has a first concentration near an interface between the channel region and the gate dielectric layer.

Abstract: An image sensor includes a pixel array and a plurality of pairs of column lines. The pixel array includes a plurality of unit pixel areas arranged in a plurality of rows and columns. Each of the unit pixel areas includes a readout circuit connected to a corresponding pair of column lines, and first and second photo-electric conversion devices sharing the readout circuit. Each of the unit pixel areas is configured to output a first pixel signal corresponding to a photoelectron generated by the first photo-electric conversion device through the first column line, and to output a second pixel signal corresponding to a photoelectron generated by the second photo-electric conversion device through the second column line.

Abstract: An analog to digital converter (ADC) can include a multi-input comparison unit configured to compare a pixel voltage from an image sensor, a comparison voltage comprising a stepped voltage modified during a coarse mode of operation, and a ramp voltage comprising a ramped voltage modified to one another during a fine mode of operation, to provide a comparison result signal that indicates whether the comparison voltage combined with the ramp voltage is greater than or less than the pixel voltage. A selection control signal generation unit can receive the comparison result signal and a mode control signal, to indicate the coarse or fine mode, to provide a selection control signal allowing modification of the comparison voltage in the coarse mode and to hold the comparison voltage constant in the fine mode. A reference voltage selection unit can receive the selection control signal to control modification of the comparison voltage.

Abstract: An image sensor includes a first column pair and a second column pair among a plurality of columns of a pixel array, an analog-to-digital converter pair, and a switch arrangement circuit configured to connect the first column pair with the analog-to-digital converter pair in response to first switch control signals such that two rows among a plurality of rows in the pixel array are read during a single access time.

Abstract: A solid state imaging device includes a pixel array comprising a plurality of photoelectric conversion devices and an analog to digital conversion (ADC) circuit configured to convert an image signal received from the pixel array to a digital signal responsive to a ramp signal and a gain setting. The solid state imaging device further includes a ramp signal generator circuit configured to generate the ramp signal with a slope that varies responsive to a control signal and a dark level offset compensation circuit configured to generate the control signal responsive to the gain setting and a dark level measurement.

Abstract: An offset canceling circuit stores charge corresponding to a voltage difference between a reset voltage received from a unit pixel and a reference voltage, thereby canceling an offset of the unit pixel.

Abstract: Methods of fabricating vertical memory devices are provided including forming a plurality of alternating insulating layers and sacrificial layers on a substrate; patterning and etching the plurality of insulating layer and sacrificial layers to define an opening that exposes at least a portion of a surface of the substrate; forming a charge trapping pattern and a tunnel insulating pattern on a side wall of the opening; forming a channel layer on the tunnel insulating layer on the sidewall of the opening, the channel layer including N-type impurity doped polysilicon; forming a buried insulating pattern on the channel layer in the opening; and forming a blocking dielectric layer and a control gate on the charge trapping pattern of one side wall of the channel layer.

Abstract: A semiconductor device includes a channel region extending in a vertical direction perpendicular to a substrate and having a nitrogen concentration distribution, a plurality of gate electrodes arranged on a side wall of the channel region and separated from each other in a vertical direction, and a gate dielectric layer disposed between the channel region and the gate electrodes. The nitrogen concentration distribution has a first concentration near an interface between the channel region and the gate dielectric layer.

Abstract: An analog-to-digital converter includes a comparison signal generation unit and a control unit. The comparison signal generation unit determines a logic level of a comparison signal by comparing an input signal with a selected reference signal based on a switch control signal in a first comparison mode, and by comparing a difference voltage with a ramp signal based on the switch control signal in a second comparison mode. The difference voltage is generated based on the input signal and the selected reference signal such that a level of the difference voltage is lower than a fine voltage level corresponding to a voltage level of the selected reference signal in the second comparison mode. The control unit generates the switch control signal based on the comparison signal and a mode selection signal.

Abstract: An apparatus includes an operational amplifier circuit comprising at least one operational amplifier and a feedback circuit coupled between the output terminal and input terminal of the operational amplifier circuit and configured to apply a feedback gain to an output signal at the output of the first operational amplifier. The apparatus further includes a variable compensation capacitor coupled to the output terminal of the operational amplifier circuit and configured to vary a capacitance thereof responsive to the feedback gain.

Abstract: A CMOS image sensor includes a photodiode, a switch configured to transfer a signal sensed by the photodiode to a sensing node, and a comparator electrically and directly connected to the sensing node and configured to compare the sensed signal of the sensing node and a ramp signal. Reset offset of the comparator is maintained at a constant offset voltage level during an initialization mode.

Abstract: A two-step analog-digital converting circuit includes a comparator, an upper bit counter and a pulse residue conversion unit. The comparator is configured to compare a ramp signal and an input signal, and to output a resulting comparative signal. The upper bit counter is configured to receive the comparative signal and a clock signal, and to output upper bit values corresponding to a first time interval between a generation time point of the ramp signal and a first edge of the clock signal, the first edge of the clock signal immediately preceding a state transition time point of the comparative signal. The pulse residue conversion unit is configured to receive the comparative signal and the clock signal, and to output lower bit values corresponding to a second time interval between the first edge of the clock signal and the state transition time point of the comparative signal.

Abstract: Non-volatile memory devices are provided including a control gate electrode on a substrate; a charge storage insulation layer between the control gate electrode and the substrate; a tunnel insulation layer between the charge storage insulation layer and the substrate; a blocking insulation layer between the charge storage insulation layer and the control gate electrode; and a material layer between the tunnel insulation layer and the blocking insulation layer, the material layer having an energy level constituting a bottom of a potential well.

Abstract: The device includes: a tunnel insulating layer, a charge trap layer; a blocking insulating layer; and a gate electrode sequentially formed on a substrate. The charge trap layer includes: plural trap layers comprising a first material having a first band gap energy level; spaced apart nanodots, each nanodot being at least partially surrounded by at least one of the trap layers, wherein the nanodots comprise a second material having a second band gap energy level that is lower than the first band gap energy level; and an intermediate blocking layer comprising a third material having a third band gap energy level that is higher than the first band gap energy level, formed between at least two of the trap layers. This structure prevents loss of charges from the charge trap layer and improves charge storage capacity.

Abstract: An image sensor includes a pixel array including a plurality of pixels which are arranged in a matrix of a plurality of rows and columns and each of the plurality of pixels being configured to convert intensity of incident light into an electrical image signal; and an extended counting analog-to-digital converter configured to perform a first analog-to-digital conversion to provide a digital signal from an output signal of the pixel array, to obtain a residue using the output signal of the pixel array and the digital signal, and to perform a second analog-to-digital conversion using the residue.

Abstract: An offset canceling circuit stores charge corresponding to a voltage difference between a reset voltage received from a unit pixel and a reference voltage, thereby canceling an offset of the unit pixel.

Abstract: An analog to digital converter (ADC) can include a multi-input comparison unit configured to compare a pixel voltage from an image sensor, a comparison voltage comprising a stepped voltage modified during a coarse mode of operation, and a ramp voltage comprising a ramped voltage modified to one another during a fine mode of operation, to provide a comparison result signal that indicates whether the comparison voltage combined with the ramp voltage is greater than or less than the pixel voltage. A selection control signal generation unit can receive the comparison result signal and a mode control signal, to indicate the coarse or fine mode, to provide a selection control signal allowing modification of the comparison voltage in the coarse mode and to hold the comparison voltage constant in the fine mode. A reference voltage selection unit can receive the selection control signal to control modification of the comparison voltage.

Abstract: An analog-to-digital converter includes a comparison signal generation unit and a control unit. The comparison signal generation unit determines a logic level of a comparison signal by comparing an input signal with a selected reference signal based on a switch control signal in a first comparison mode, and by comparing a difference voltage with a ramp signal based on the switch control signal in a second comparison mode. The difference voltage is generated based on the input signal and the selected reference signal such that a level of the difference voltage is lower than a fine voltage level corresponding to a voltage level of the selected reference signal in the second comparison mode. The control unit generates the switch control signal based on the comparison signal and a mode selection signal.

Abstract: An image sensor for high-speed data readout is provided. The image sensor includes a line memory block temporarily storing a digital signal in unit of lines which is generated based on an analog signal output from a pixel array. The line memory block includes a plurality of line memories, a plurality of data line pairs respectively connecting the line memories to a sense amplifying unit, and a plurality of data line prechargers each including at least two precharge units separately connected with a corresponding one of the data line pairs to precharge the corresponding data line pair with a predetermined precharge voltage. Accordingly, the image sensor performs high-speed digital signal readout based on precharge operation of the data line prechargers.