摘要:
An address sequencer is fabricated on a semiconductor substrate having flash memory cells fabricated thereon for sequencing through the flash memory cells during BIST (built-in-self-test) of the flash memory cells. The address sequencer includes an address sequencer control logic and address sequencer buffers fabricated on the semiconductor substrate. The address sequencer buffers generate a plurality of bits indicating an address of the flash memory cells. The address sequencer control logic controls the buffers to sequence through a respective sequence of bit patterns for each of a plurality of BIST modes.
摘要:
In a method and system for repairing defective flash memory cells fabricated on a semiconductor substrate, a repair controller and a plurality of voltage sources are fabricated on the semiconductor substrate. The repair controller controls the voltage sources to apply programming voltages on respective CAM (content addressable memory) flash memory cells in a JUICE state for replacing the defective flash memory cells with a corresponding redundancy element of flash memory cells. In addition, a FAILREP logic is fabricated on the semiconductor substrate for entering a HANG state if no redundancy element of flash memory cells is available or if the defective flash memory cells have been previously repaired.
摘要:
In a method and system for diagnosing a back-end state machine used for testing flash memory cells fabricated on a semiconductor substrate, a signal selector and a diagnostic matching logic are fabricated on the semiconductor substrate. The diagnostic matching logic sets a generated match output to a pass or fail state depending on control variables from the back-end state machine. The signal selector selects the generated match output to be used in a verify step of a BIST (built-in-self-test) mode, if a diagnostic mode is invoked. The back-end state machine performs a plurality of BIST modes with the generated match output, for testing the functionality of the back-end state machine.
摘要:
For generating a margining voltage for biasing a gate of a CAM (content addressable memory) cell of a flash memory device fabricated on a semiconductor wafer, a high voltage source is provided with a voltage generator fabricated on the semiconductor wafer. A low voltage source is provided from a node coupled to the voltage generator fabricated on the semiconductor wafer. For example, the voltage generator for providing the high voltage source includes a voltage regulator and a charge pump fabricated on the semiconductor wafer, and the low voltage source is the ground node. In addition, a first transistor is coupled to the high voltage source, and a second transistor is coupled to the low voltage source. A first resistor is coupled between the first transistor and an output node, and a second resistor coupled between the second transistor and the output node. The margining voltage is generated at the output node. The first resistor and the second resistor form a resistive voltage divider at the output node between the high voltage source and the low voltage source when the first transistor and the second transistor are turned on. A logic circuit turns on the first transistor and the second transistor when a first set of control signals indicate that program margining of the CAM cell during a BIST (built-in-self-test) mode is invoked. The first transistor, the second transistor, the first resistor, the second resistor, and the logic circuit are fabricated on the semiconductor wafer. In another embodiment of the present invention, the logic circuit turns off the first transistor and turns on the second transistor such that the output node discharges to a voltage of the low voltage source for erase margining of the CAM cell.
摘要:
A memory system is programmed with minimal program disturb and reduced junction and channel leakage during self-boosting. Pre-charging bias signals are applied to word lines adjacent to a selected word line before a program signal is applied to the selected word line and a pass signal is applied to the remaining word lines. The pre-charging bias signals apply a pre-charge to the memory cells. The pre-charging bias signals are chosen to improve the isolation of the memory cells on word lines adjacent to the selected word line, improve self boost efficiency and reduce current leakage to prevent or reduce program disturb and/or programming errors especially in the inhibited memory cells on the selected word line.
摘要:
An organic memory cell made of two electrodes with a selectively conductive media between the two electrodes is disclosed. The selectively conductive media contains an organic layer and passive layer. The selectively conductive media is programmed by applying bias voltages that program a desired impedance state for a memory cell. The desired impedance state represents one or more bits of information and the memory cell does not require constant power or refresh cycles to maintain the desired impedance state. Furthermore, the selectively conductive media is read by applying a current and reading the impedance of the media in order to determine the impedance state of the memory cell. Methods of making the organic memory devices/cells, methods of using the organic memory devices/cells, and devices such as computers containing the organic memory devices/cells are also disclosed.
摘要:
A memory device having multiple banks, each bank having multiple memory cells and a method of programming multiple memory cells in the device wherein a bias voltage is applied to a common source terminal of the multiple memory cells and a time varying voltage is applied to gates of the memory cells that are to be programmed. In one embodiment, the voltage applied to the gates of the memory cells to be programmed is a ramp voltage. In a second embodiment, the voltage applied to the gates of the memory cells to be programmed is an increasing step voltage. In another embodiment, the bias voltage applied to the common source terminal and the voltage applied to the control gates of the memory cells to be programmed are selected so that the current flowing through cells being programmed is reduced and that the leakage current from memory cells that are not to be programmed is substantially eliminated. In another embodiment, a bias voltage is applied to the common source terminal and a bias voltage is applied to the common well voltage. The combination of the voltages applied to the control gates and to the sources decreases loading on the bitlines to ensure that VDS does not fall below a required level necessary for the maintenance of the hot carrier effect during programming. A bias voltage can also be applied to the wells of the memory cells while the common source terminal is held at ground. Feedback control of the programming gate voltages can be used to control the power required for programming.
摘要:
A memory cell made of two electrodes with a controllably conductive media between the two electrodes is disclosed. The controllably conductive media contains an active low conductive layer and passive layer. The controllably conductive media changes its impedance when an external stimuli such as an applied electric field is imposed thereon. Methods of making the memory devices/cells, methods of using the memory devices/cells, and devices such as computers containing the memory devices/cells are also disclosed.
摘要:
Systems and methods employing at least one constant current source to facilitate programming of an organic memory cell and/or employing at least one constant voltage source to facilitate erasing of a memory device. The present invention is utilized in single memory cell devices and memory cell arrays. Employing a constant current source prevents current spikes during programming and allows accurate control of a memory cell's state during write cycles, independent of the cell's resistance. Employing a constant voltage source provides a stable load for memory cells during erase cycles and allows for accurate voltage control across the memory cell despite large dynamic changes in cell resistance during the process.
摘要:
The present invention facilitates semiconductor devices by aiding the efficiency in the way individual devices change states in a semiconductor array. State change voltages can be applied to a single device in the array of semiconductor devices without the need for transistor-type voltage controls. The diodic effect of the present invention facilitates this activity by allowing specific voltage levels necessary for state changes to only occur at the desired device. In this manner, an array of devices can be programmed with varying data or states without utilizing transistor technology. The present invention also allows for an extremely efficient method of producing these types of devices, eliminating the need to manufacture costly external voltage controlling semiconductor devices.