摘要:
On the same semiconductor substrate 1, a memory cell array in which a plurality of memory elements R having a chalcogenide-material storage layer 22 storing a high-resistance state with a high electric resistance value and a low-resistance state with a low electric resistance value by a change of an atom arrangement are disposed in a matrix is formed in a memory cell region mmry, and a semiconductor integrated circuit is formed in a logic circuit region lgc. This chalcogenide-material storage layer 22 is made of a chalcogenide material containing at least either one of Ga or In of 10.5 atom % or larger to 40 atom % or smaller, Ge of 5 atom % or larger to 35 atom % or smaller, Sb of 5 atom % or larger to 25 atom % or smaller, and Te of 40 atom % or larger to 65 atom % or smaller.
摘要:
On the same semiconductor substrate 1, a memory cell array in which a plurality of memory elements R having a chalcogenide-material storage layer 22 storing a high-resistance state with a high electric resistance value and a low-resistance state with a low electric resistance value by a change of an atom arrangement are disposed in a matrix is formed in a memory cell region mmry, and a semiconductor integrated circuit is formed in a logic circuit region lgc. This chalcogenide-material storage layer 22 is made of a chalcogenide material containing at least either one of Ga or In of 10.5 atom % or larger to 40 atom % or smaller, Ge of 5 atom % or larger to 35 atom % or smaller, Sb of 5 atom % or larger to 25 atom % or smaller, and Te of 40 atom % or larger to 65 atom % or smaller.
摘要:
In a semiconductor device including a phase change memory element whose memory layer is formed of a phase change material of M (additive element)-Ge (germanium)-Sb (antimony)-Te (tellurium), both of high heat resistance and stable data retention property are achieved. The memory layer has a fine structure with a different composition ratio therein, and an average composition of MαGeXSbYTeZ forming the memory layer satisfies the relations of 0≦α≦0.4, 0.04≦X≦0.4, 0≦Y≦0.3, 0.3≦Z≦0.6, and 0.03≦(α+Y).
摘要:
The annealing process at 400° C. or more required for the wiring process for a phase change memory has posed the problem in that the crystal grains in a chalcogenide material grow in an oblique direction to cause voids in a storage layer. The voids, in turn, cause peeling due to a decrease in adhesion, variations in resistance due to improper contact with a plug, and other undesirable events. After the chalcogenide material has been formed in an amorphous phase, post-annealing is conducted to form a (111)-oriented and columnarly structured face-centered cubic. This is further followed by high-temperature annealing to form a columnar, hexagonal closest-packed crystal. Use of this procedure makes it possible to suppress the growth of inclined crystal grains that causes voids, since crystal grains are formed in a direction perpendicular to the surface of an associated substrate.
摘要:
The annealing process at 400° C. or more required for the wiring process for a phase change memory has posed the problem in that the crystal grains in a chalcogenide material grow in an oblique direction to cause voids in a storage layer. The voids, in turn, cause peeling due to a decrease in adhesion, variations in resistance due to improper contact with a plug, and other undesirable events. After the chalcogenide material has been formed in an amorphous phase, post-annealing is conducted to form a (111)-oriented and columnarly structured face-centered cubic. This is further followed by high-temperature annealing to form a columnar, hexagonal closest-packed crystal. Use of this procedure makes it possible to suppress the growth of inclined crystal grains that causes voids, since crystal grains are formed in a direction perpendicular to the surface of an associated substrate.
摘要:
With a high-speed nonvolatile phase change memory, reliability in respect of the number of refresh times is enhanced. In a memory cell forming area of a phase change memory using a MISFET as a transistor for selection of memory cells, a phase change material layer of a memory cell comprising a resistor element, using a phase change material, is formed for common use. As a result, variation in shape and a change in composition of the phase change material, caused by isolation of memory cell elements by etching, are reduced, thereby enhancing reliability of memory cells, in respect of the number of refresh times.
摘要:
A phase-change memory device including a memory cell having a memory element and a select transistor is improved in heat resistance so that it may be operable at 145° C. or higher.The memory layer is used which has a content of Zn or Cd of 20 at % or more and 50 at % or less, a content of Ge or Sb of 5 at % or more and 25 at % or less, and a content of Te of 40 at % or more and 65 at % or less in Zn-Ge-Te.
摘要:
With a high-speed nonvolatile phase change memory, reliability in respect of the number of refresh times is enhanced. In a memory cell forming area of a phase change memory using a MISFET as a transistor for selection of memory cells, a phase change material layer of a memory cell comprising a resistor element, using a phase change material, is formed for common use. As a result, variation in shape and a change in composition of the phase change material, caused by isolation of memory cell elements by etching, are reduced, thereby enhancing reliability of memory cells, in respect of the number of refresh times.
摘要:
In a non-volatile phase change memory, information is recorded by utilizing a change in resistance of a phase change portion. When the phase change portion is allowed to generate Joule's heat and is held at a specific temperature, it goes into a state of a low resistance. When the gate voltage of a memory cell selection transistor QM is controlled to afford a low resistance state, the maximum amount of current applied to the phase change portion is limited by the application of a medium-state voltage to the control gate, thereby avoiding overheating of the phase change portion.
摘要:
In a non-volatile phase change memory, information is recorded by utilizing a change in resistance of a phase change portion. When the phase change portion is allowed to generate Joule's heat and is held at a specific temperature, it goes into a state of a low resistance. When the gate voltage of a memory cell selection transistor QM is controlled to afford a low resistance state, the maximum amount of current applied to the phase change portion is limited by the application of a medium-state voltage to the control gate, thereby avoiding overheating of the phase change portion.