Abstract: For decreasing a recording current and suppressing a cross erase simultaneously, a three-dimensional phase-change memory for attaining higher sensitivity and higher reliability by the provision of a chalcogenide type interface layer is provided, in which an electric resistivity, a thermal conductivity, and a melting point of the material of the interface layer are selected appropriately, thereby improving the current concentration to the phase-change material and thermal and material insulation property with Si channel upon writing.

Abstract: On an insulating film (41) in which a plug (43) as a lower electrode is embedded, a laminated layer pattern of an insulating film (51) made of tantalum oxide, a recording layer (52) made of Ge—Sb—Te based chalcogenide to which indium is introduced and an upper electrode film (53) made of tungsten or tungsten alloy is formed, thereby forming a phase change memory. By interposing the insulating film (51) between the recording layer (52) and the plug (43), an effect of reducing programming current of a phase change memory and an effect of preventing peeling of the recording layer (52) can be achieved. Further, by using the Ge—Sb—Te based chalcogenide to which indium is introduced as the recording layer (52), the difference in work function between the insulating film (51) and the recording layer (52) is increased, and the programming voltage of the phase change memory can be reduced.

Abstract: A vertical chain memory includes two-layer select transistors having first select transistors which are vertical transistors arranged in a matrix, and second select transistors which are vertical transistors formed on the respective first select transistors, and a plurality of memory cells connected in series on the two-layer select transistors. With this configuration, the adjacent select transistors are prevented from being selected by respective shared gates, the plurality of two-layer select transistors can be selected, independently, and a storage capacity of a non-volatile storage device is prevented from being reduced.

Abstract: 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.

Abstract: There is provided a semiconductor storage device which is capable of further reducing a size of a memory cell, and increasing a storage capacity. Plural memory cells each including a transistor formed on a semiconductor substrate, and a variable resistive device having a resistance value changed by voltage supply and connected between source and drain terminals of the transistor are arranged longitudinally and in an array to configure a three-dimensional memory cell array. A memory cell structure has a double channel structure in which an inside of a switching transistor is filled with a variable resistance element, particularly, a phase change material. The switching transistor is turned off by application of a voltage to increase a channel resistance so that a current flows in the internal phase change material to operate the memory.

Abstract: An object of the present invention is to provide a technique for suppressing thermal disturbance of a phase change memory device having a three-dimensional structure. In the phase change memory device having a three-dimensional structure, a material having a high thermal conductivity is used as a gate insulation film of a MOS transistor for selection, and causes heat transmitted to a Si channel layer from a phase change recording film to successfully diffuse to a gate electrode. In this way, since heat generated from a recording bit diffuses to a non-selected bit adjacent to it, it is possible to suppress thermal disturbance. BN, Al2O3, AlN, TiO2, Si3N4, ZnO and the like are useful as a gate insulation film having a high thermal conductivity.

Abstract: A recording layer 52 made of a chalcogenide material which stores a high-resistance state of a high electrical resistance value and a low-resistance state of a low electrical resistance value is used as a memory element RM in a memory cell region, and it is formed so that a concentration of Ga or In of a first layer 52a positioned on a lower electrode TP side of the recording layer 52 is higher than the corresponding concentration of a second layer 52b positioned on an upper electrode 53 side. For example, the recording layer is formed so that a content of Ga or In of the second layer is 5 atomic % or more smaller than that of the first layer. Also, a circuit which can reverse the voltage polarity between the upper electrode and the lower electrode in a set operation and a reset operation is provided.

Abstract: There is provided a semiconductor storage device which is capable of further reducing a size of a memory cell, and increasing a storage capacity. Plural memory cells each including a transistor formed on a semiconductor substrate, and a variable resistive device having a resistance value changed by voltage supply and connected between source and drain terminals of the transistor are arranged longitudinally and in an array to configure a three-dimensional memory cell array. A memory cell structure has a double channel structure in which an inside of a switching transistor is filled with a variable resistance element, particularly, a phase change material. The switching transistor is turned off by application of a voltage to increase a channel resistance so that a current flows in the internal phase change material to operate the memory.

Abstract: There is provided a semiconductor storage device which is capable of further reducing a size of a memory cell, and increasing a storage capacity. Plural memory cells each including a transistor formed on a semiconductor substrate, and a variable resistive device having a resistance value changed by voltage supply and connected between source and drain terminals of the transistor are arranged longitudinally and in an array to configure a three-dimensional memory cell array. A memory cell structure has a double channel structure in which an inside of a switching transistor is filled with a variable resistance element, particularly, a phase change material. The switching transistor is turned off by application of a voltage to increase a channel resistance so that a current flows in the internal phase change material to operate the memory.

Abstract: For decreasing a recording current and suppressing a cross erase simultaneously, a three-dimensional phase-change memory for attaining higher sensitivity and higher reliability by the provision of a chalcogenide type interface layer is provided, in which an electric resistivity, a thermal conductivity, and a melting point of the material of the interface layer are selected appropriately, thereby improving the current concentration to the phase-change material and thermal and material insulation property with Si channel upon writing.

Abstract: A phase change memory is formed of a plug buried within a through-hole in an insulating film formed on a semiconductor substrate, an interface layer formed on the insulating film in which the plug is buried, a recording layer formed of a chalcogenide layer formed on the interface layer, and an upper contact electrode formed on the recording layer. The recording layer storing information according to resistance value change is made of chalcogenide material containing indium in an amount range from 20 atomic % to 38 atomic %, germanium in a range from 9 atomic % to 28 atomic %, antimony in a range from 3 atomic % to 18 atomic %, and tellurium in a range from 42 atomic % to 63 atomic %, where the content of germanium larger than or equal to the content of antimony.

Abstract: In a phase-change memory, an interface layer is inserted between a chalcogenide material layer and a plug. The interface layer is arranged so as not to cover the entire interface of a plug-like electrode. When the plug is formed at an upper part than the chalcogenide layer, the degree of integration is increased. The interface layer is formed by carrying out sputtering using an oxide target, or, by forming a metal film by carrying out sputtering using a metal target followed by oxidizing the metal film in an oxidation atmosphere such as oxygen radical, oxygen plasma, etc.

Abstract: There is provided a semiconductor storage device which is capable of further reducing a size of a memory cell, and increasing a storage capacity. Plural memory cells each including a transistor formed on a semiconductor substrate, and a variable resistive device having a resistance value changed by voltage supply and connected between source and drain terminals of the transistor are arranged longitudinally and in an array to configure a three-dimensional memory cell array. A memory cell structure has a double channel structure in which an inside of a switching transistor is filled with a variable resistance element, particularly, a phase change material. The switching transistor is turned off by application of a voltage to increase a channel resistance so that a current flows in the internal phase change material to operate the memory.

Abstract: 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 M?GeXSbYTeZ forming the memory layer satisfies the relations of 0???0.4, 0.04?X?0.4, 0?Y?0.3, 0.3?Z?0.6, and 0.03?(?+Y).

Abstract: A phase change memory is formed of a plug buried within a through-hole in an insulating film formed on a semiconductor substrate, an interface layer formed on the insulating film in which the plug is buried, a recording layer formed of a chalcogenide layer formed on the interface layer, and an upper contact electrode formed on the recording layer. The recording layer storing information according to resistance value change is made of chalcogenide material containing indium in an amount range from 20 atomic % to 38 atomic %, germanium in a range from 9 atomic % to 28 atomic %, antimony in a range from 3 atomic % to 18 atomic %, and tellurium in a range from 42 atomic % to 63 atomic %, where the content of germanium larger than or equal to the content of antimony.

Abstract: A recording layer 52 made of a chalcogenide material which stores a high-resistance state of a high electrical resistance value and a low-resistance state of a low electrical resistance value is used as a memory element RM in a memory cell region, and it is formed so that a concentration of Ga or In of a first layer 52a positioned on a lower electrode TP side of the recording layer 52 is higher than the corresponding concentration of a second layer 52b positioned on an upper electrode 53 side. For example, the recording layer is formed so that a content of Ga or In of the second layer is 5 atomic % or more smaller than that of the first layer. Also, a circuit which can reverse the voltage polarity between the upper electrode and the lower electrode in a set operation and a reset operation is provided.

Abstract: In a step of forming an InGeSbTe film which contains GeSbTe made of germanium (Ge), antimony (Sb) and tellurium (Te) as its base material and to which indium (In) is added, an InGeSbTe film is formed by sputtering on a semiconductor substrate while keeping a temperature of the semiconductor substrate between an in-situ crystallization temperature of GeSbTe serving as the base material and an in-situ crystallization temperature of InGeSbTe. As a result, it is possible to suppress the failure that the phase separation occurs in the InGeSbTe film during the following manufacturing process.

Abstract: On an insulating film (41) in which a plug (43) as a lower electrode is embedded, a laminated layer pattern of an insulating film (51) made of tantalum oxide, a recording layer (52) made of Ge—Sb—Te based chalcogenide to which indium is introduced and an upper electrode film (53) made of tungsten or tungsten alloy is formed, thereby forming a phase change memory. By interposing the insulating film (51) between the recording layer (52) and the plug (43), an effect of reducing programming current of a phase change memory and an effect of preventing peeling of the recording layer (52) can be achieved. Further, by using the Ge—Sb—Te based chalcogenide to which indium is introduced as the recording layer (52), the difference in work function between the insulating film (51) and the recording layer (52) is increased, and the programming voltage of the phase change memory can be reduced.

Abstract: 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.

Abstract: 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.