Abstract:
A nonvolatile memory element includes: a first electrode layer; a second electrode layer; and a variable resistance layer which is placed between the electrode layers, and whose resistance state reversibly changes between a high resistance state and a low resistance state based on a polarity of a voltage applied between the electrode layers. The variable resistance layer is formed by stacking a first oxide layer including an oxide of a first transition metal and a second oxide layer including an oxide of a second transition metal which is different from the first transition metal. At least one of the following conditions is satisfied: (1) a dielectric constant of the second oxide layer is larger than a dielectric constant of the first oxide layer; and (2) a band gap of the second oxide layer is smaller than a band gap of the first oxide layer.
Abstract:
A method includes applying a first polarity writing voltage pulse to a metal oxide layer to change its resistance state from high to low into a write state, applying a second polarity erasing voltage pulse different from the first polarity to the metal oxide layer to change its resistance state from low to high into an erase state, and applying an initial voltage pulse having the second polarity to the metal oxide layer before first application of the writing voltage pulse, to change an initial resistance value of the metal oxide layer. R0>RH>RL and |V0|>|Ve|≧|Vw| are satisfied where R0, RL, and RH are the resistance values of the initial, write, and erase states, respectively, of the metal oxide layer, and V0, Vw, and Ve are voltage values of the initial, writing, and erasing voltage pulses, respectively.
Abstract:
A nonvolatile memory element of the present invention comprises a first electrode (103), a second electrode (108); a resistance variable layer (107) which is interposed between the first electrode (103) and the second electrode (107) and is configured to switch a resistance value reversibly in response to an electric signal applied between the electrodes (103) and (108), and the resistance variable layer (107) has at least a multi-layer structure in which a first hafnium-containing layer having a composition expressed as HfOx (0.9≦x≦1.6), and a second hafnium-containing layer having a composition expressed as HfOy (1.8
Abstract:
A nonvolatile semiconductor memory apparatus (10) of the present invention comprises a substrate (10), lower-layer electrode wires (15) provided on the substrate (11), an interlayer insulating layer (16) which is disposed on the substrate (11) including the lower-layer electrode wires (15) and is provided with contact holes at locations respectively opposite to the lower-layer electrode wires (15), resistance variable layers (18) which are respectively connected to the lower-layer electrode wires (15); and non-ohmic devices (20) which are respectively provided on the resistance variable layers (18) such that the non-ohmic devices are respectively connected to the resistance variable layers (18). The non-ohmic devices (20) each has a laminated-layer structure including plural semiconductor layers, a laminated-layer structure including a metal electrode layer and an insulator layer, or a laminated-layer structure including a metal electrode layer and a semiconductor layer. One layer of the laminated-layer structure is embedded to fill each of the contact holes and the semiconductor layer or the insulator layer which is the other layer of the laminated-layer structure has a larger area than an opening of each of the contact holes and is provided on the interlayer insulating layer (16).
Abstract:
A nonvolatile memory apparatus and a nonvolatile data storage medium of the present invention, including nonvolatile memory elements each of which changes its resistance in response to electric pulses applied, comprises a first write circuit for performing first write in which a first electric pulse is applied to the nonvolatile memory element to switch a resistance value of the nonvolatile memory element from a first resistance value to a second resistance value and a second electric pulse which is opposite in polarity to the first electric pulse is applied to the nonvolatile memory element to switch the resistance value of the nonvolatile memory element from the second resistance value to the first resistance value.
Abstract:
The present invention is configured such that a resistance variable element (16) and a rectifying element (20) are formed on a substrate (12). The resistance variable element (16) is configured such that a resistance variable layer (14) made of a metal oxide material is sandwiched between a lower electrode (13) and an upper electrode (15). The rectifying element (20) is connected to the resistance variable element (16), and is configured such that a blocking layer (18) is sandwiched between a first electrode layer (17) located on a lower side of the blocking layer (18) and a second electrode layer (19) located on an upper side of the blocking layer (18). The resistance variable element (16) and the rectifying element (20) are connected to each other in series in a thickness direction of the resistance variable layer (14), and the blocking layer (18) is formed as a barrier layer having a hydrogen barrier property.
Abstract:
A nonvolatile memory element comprises a first electrode layer (103), a second electrode (107), and a resistance variable layer (106) which is disposed between the first electrode layer (103) and the second electrode layer (107), a resistance value of the resistance variable layer varying reversibly according to electric signals having different polarities which are applied between the electrodes (103), (107), wherein the resistance variable layer (106) has a first region comprising a first oxygen-deficient tantalum oxide having a composition represented by TaOx (0
Abstract:
A nonvolatile memory element of the present invention comprises a first electrode (103); a second electrode (109); and a resistance variable layer (106) disposed between the first electrode and the second electrode, resistance values of the resistance variable layer reversibly changing in response to electric signals applied between the first electrode and the second electrode; at least one of the first electrode and the second electrode including a platinum-containing layer (107) comprising platinum; the resistance variable layer including at least a first oxygen-deficient transition metal oxide layer (104) which is not physically in contact with the platinum-containing layer and a second oxygen-deficient transition metal oxide layer (105) which is disposed between the first oxygen-deficient transition metal oxide layer and the platinum-containing layer and is physically in contact with the platinum-containing layer; x
Abstract:
A sample stirring device of the present invention includes a driving roller and two follower rollers for coming into contact with a sample container including a cylindrical portion for containing a sample to be stirred. The driving roller is driven for rotation to stir the sample contained in the sample container. The two follower rollers have rotation axes inclined with respect to an axial direction of the cylindrical portion. This arrangement allows the sample container such as a blood collection tube to be rotated stably.
Abstract:
A spatial coupling provided between an amplified-light waveguide and an output-light waveguide includes a wavelength selecting element that selectively transmits a light having a desired wavelength band out of a spontaneous emission light generated in the amplified-light waveguide and a lens unit that couples the spontaneous emission light to the wavelength selecting unit. An input-side light reflecting unit provided between a semiconductor pumping laser and the amplified-light waveguide and an output-side light reflecting unit formed on an output side of the spatial coupling unit form a laser resonator.