摘要:
A phase-change cell memory device includes a plurality of phase-change memory cells, an address circuit, a write driver, and a write driver control circuit. The phase-change memory cells each include a volume of material that is programmable between amorphous and crystalline states. The address circuit selects at least one of the memory cells, and the write driver generates a reset pulse current to program a memory cell selected by the address circuit into the amorphous state, and a set pulse current to program the memory cell selected by the address circuit into the crystalline state. The write driver control circuit varies at least one of a pulse width and a pulse count of at least one of the reset and set pulse currents according to a load between the write driver and the memory cell selected by the address circuit.
摘要:
Phase change memory devices may include a semiconductor substrate of a first conductivity type and a plurality of parallel word lines disposed on the semiconductor substrate. The word lines may have a second conductivity type different from the first conductivity type and substantially flat top surfaces. First and second semiconductor patterns may be sequentially stacked on each word line, and an insulating layer may be provided to fill gap regions between the word lines, gap regions between the first semiconductor patterns and gap regions between the second semiconductor patterns. A plurality of phase change material patterns may be two-dimensionally arrayed on the insulating layer and electrically connected to the second semiconductor patterns.
摘要:
A firing method of a phase change memory device and a phase change memory capable of effectively performing a firing operation are described. The phase change memory device includes a plurality of memory cell array blocks, a counter clock generation unit, a decoding unit, and a driving unit. Each memory cell array block has phase change memory cells. The counter clock generation unit outputs first through third counter clock signals in response to an external clock signal and a firing mode signal, wherein the first through third counter clock signals have different cycles. The decoding unit, in response to the first through third counter clock signals, outputs a block address which selects one of the plurality of memory cell array blocks, word line addresses which enable word lines of the selected memory cell array block, and a redundant word line address which enables a redundant word line of the selected memory cell array block. The driving unit applies a firing current to the memory cell array blocks in response to the firing mode signal. According to the phase change memory device and the initial firing method, the time taken to perform the initial firing operation can be reduced. In addition, since the numbers of the needed signals are minimized, a large number of chips on a single wafer can be simultaneously tested.
摘要:
Phase change memory devices having cell diodes and related methods are provided, where the phase change memory devices include a semiconductor substrate of a first conductivity type and a plurality of parallel word lines disposed on the semiconductor substrate, the word lines have a second conductivity type different from the first conductivity type and have substantially flat top surfaces, a plurality of first semiconductor patterns are one-dimensionally arrayed on each word line along a length direction of the word line, the first semiconductor patterns have the first conductivity type or the second conductivity type, second semiconductor patterns having the first conductivity type are stacked on the first semiconductor patterns, an insulating layer is provided on the substrate having the second semiconductor patterns, the insulating layer fills gap regions between the word lines, gap regions between the first semiconductor patterns and gap regions between the second semiconductor patterns, a plurality of phase change material patterns are two-dimensionally arrayed on the insulating layer, and the phase change material patterns are electrically connected to the second semiconductor patterns, respectively.
摘要:
A method for programming a phase-change memory array and circuit of a phase-change memory device, each having a plurality of phase-change memory cells, may enable all the phase-change memory cells therein to be changed or set at a set resistance state, and may reduce the time needed to change the phase-change memory array to the set resistance state. In the method, a set current pulse having first through nth stages may be applied to the cells of the array to change the cells to the set resistance state. A minimum current level of the set current pulse applied to the phase-change memory cells in any stage may be higher than a reference current level for the cells of the array. A given current level of the set current pulse may be sequentially reduced from stage to stage.
摘要:
A phase-change cell memory device includes a plurality of phase-change memory cells, an address circuit, a write driver, and a write driver control circuit. The phase-change memory cells each include a volume of material that is programmable between amorphous and crystalline states. The address circuit selects at least one of the memory cells, and the write driver generates a reset pulse current to program a memory cell selected by the address circuit into the amorphous state, and a set pulse current to program the memory cell selected by the address circuit into the crystalline state. The write driver control circuit varies at least one of a pulse width and a pulse count of at least one of the reset and set pulse currents according to a load between the write driver and the memory cell selected by the address circuit.
摘要:
A phase-change cell memory device includes a plurality of phase-change memory cells, an address circuit, a write driver, and a write driver control circuit. The phase-change memory cells each include a volume of material that is programmable between amorphous and crystalline states. The address circuit selects at least one of the memory cells, and the write driver generates a reset pulse current to program a memory cell selected by the address circuit into the amorphous state, and a set pulse current to program the memory cell selected by the address circuit into the crystalline state. The write driver control circuit varies at least one of a pulse width and a pulse count of at least one of the reset and set pulse currents according to a load between the write driver and the memory cell selected by the address circuit.
摘要:
Phase change memory devices having cell diodes and related methods are provided, where the phase change memory devices include a semiconductor substrate of a first conductivity type and a plurality of parallel word lines disposed on the semiconductor substrate, the word lines have a second conductivity type different from the first conductivity type and have substantially flat top surfaces, a plurality of first semiconductor patterns are one-dimensionally arrayed on each word line along a length direction of the word line, the first semiconductor patterns have the first conductivity type or the second conductivity type, second semiconductor patterns having the first conductivity type are stacked on the first semiconductor patterns, an insulating layer is provided on the substrate having the second semiconductor patterns, the insulating layer fills gap regions between the word lines, gap regions between the first semiconductor patterns and gap regions between the second semiconductor patterns, a plurality of phase change material patterns are two-dimensionally arrayed on the insulating layer, and the phase change material patterns are electrically connected to the second semiconductor patterns, respectively.
摘要:
Phase change memory devices having cell diodes and related methods are provided, where the phase change memory devices include a semiconductor substrate of a first conductivity type and a plurality of parallel word lines disposed on the semiconductor substrate, the word lines have a second conductivity type different from the first conductivity type and have substantially flat top surfaces, a plurality of first semiconductor patterns are one-dimensionally arrayed on each word line along a length direction of the word line, the first semiconductor patterns have the first conductivity type or the second conductivity type, second semiconductor patterns having the first conductivity type are stacked on the first semiconductor patterns, an insulating layer is provided on the substrate having the second semiconductor patterns, the insulating layer fills gap regions between the word lines, gap regions between the first semiconductor patterns and gap regions between the second semiconductor patterns, a plurality of phase change material patterns are two-dimensionally arrayed on the insulating layer, and the phase change material patterns are electrically connected to the second semiconductor patterns, respectively.
摘要:
A method of biasing a memory cell array during a data writing operation and a semiconductor memory device are provided. The semiconductor memory device includes: a memory cell array including a plurality of memory cells in which a first terminal of a memory cell is connected to a corresponding first line among a plurality of first lines and a second terminal of a memory cell is connected to a corresponding second line among a plurality of second lines; and a bias circuit for biasing a selected second line to a first voltage and non-selected second lines to a second voltage.