JP3994444B2 - Electronic components - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an electronic member, a semiconductor device, an optical device, and an actuator composed of a charge transition (CT) gap type strongly correlated electronic material.
[0002]
[Prior art]
  A semiconductor device using a magnetic semiconductor that transitions between a ferromagnetic state and a paramagnetic state due to the presence or absence of a magnetic polaron is disclosed in Japanese Patent Application Laid-Open No. 07-95754. The semiconductor device disclosed in this publication can alternately transfer a magnetic semiconductor layer to a ferromagnetic material and a paramagnetic material by applying an electric field to control the formation of a magnetic polaron.Such a material is known as a typical material as a magnetic semiconductor, but has a possibility of being applied as a strongly correlated electron substance.
[0003]
[Problems to be solved by the invention]
However, the magnetic semiconductor material disclosed in this publication is EuO to which Gd is added, the operating temperature range is 100 K (absolute temperature) or less, and operation at room temperature is difficult.
In addition, as an application example of this semiconductor device, this publication only discloses an actuator that applies switching between ferromagnetism and paramagnetism of a semiconductor device, and establishment of application technology is desired.
[0004]
Furthermore, conventionally, an electronic member that combines the magnetic properties and electrical or optical properties of a semiconductor layer has not been known.
[0005]
This invention is made | formed in view of the said actual condition, and it aims at providing the electronic member which can switch a magnetic characteristic at normal temperature.
[0006]
[Means for Solving the Problems]
  In order to achieve the above object, an electronic member of the present invention comprises:
  La _1-x Sr _x MnO _Three (0.175 ≦ x ≦ 0.4), Nd _1-x Sr _x MnO _Three (0.2 ≦ x ≦ 0.4), La _1-x Ca _x MnO _Three (0.175 ≦ x <0.4), Nd _0.5 Pd _0.5 MnO _Three , And oxygen deficiency exists or oxygen deficiency does not existA strongly correlated electronic material layer;
  An electric field applying means for applying an electric field to the strongly correlated electron material layer so as to change carrier mobility, magnetization, magnetic transition temperature, transmittance, Faraday effect, Kerr effect, etc. of the strongly correlated electron material layer;
  It is characterized by comprising.
[0007]
In the strongly correlated electronic material, carrier mobility, magnetization, magnetic transition temperature, transmittance, Faraday effect, Kerr effect, and the like change according to the applied electric field. Therefore, these characteristics of the strongly correlated electronic material can be controlled by the electric field applying means and used as a current switch, an optical switch, a display device or the like. An actuator can also be configured by using a change in magnetization of a strongly correlated electron material.
[0008]
  The strongly correlated electronic material layer isIt is desirable to include oxygen defects.
[0009]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an electronic member according to an embodiment of the present invention will be described.
First, regarding the charge transition gap type strongly correlated electronic material used in the present invention, La_1-xSr_xMnO_ThreeWill be described as an example.
Among these materials, the Mn d electrons (d orbital electrons) are responsible for magnetism and electrical conductivity. Manganese ion Mn^3-As shown in FIG. 1, six oxygen ions O^2-(6 coordination).
[0010]
The d orbital of Mn is a triple degenerate orbital (t2 due to the influence of the O crystal field)._gOrbit) and double degenerate orbit (e_gOrbit), and each d orbit forms an energy band. LaMnO_Three(La²⁺, Mn³⁺, O^2-), As shown in FIG.³⁺Accommodates four electrons in the d orbit. In the normal band approximation band theory, in this state, LaMnO_ThreeIs a metal. However, in this system, electrons cannot move due to strong Coulomb interaction between electrons, and LaMnO_ThreeBecomes an insulator.
[0011]
As a method of making this system an electric conductor, a double degenerate d-orbit (e_gThere are times when holes are introduced into the orbit. For example, La³⁺Part of Sr²⁺When substituted with Mn³⁺Part of Mn⁴⁺Thus, as shown schematically in FIG. 2B, some of the double-degenerate d-orbits are vacant. For this reason, electrons (holes) can move, and this system becomes an electric conductor.
[0012]
e_gThe orbit is relatively broad because it is strongly hybridized with the oxygen 2p orbit. On the other hand, t_2gThe orbit has a strong locality and can be considered as a localized spin approximately.
[0013]
LaMnO_ThreeIs antiferromagnetic, so t_2gOrbital spins are parallel in opposite directions. However, when Sr is doped, as described above, electrons (holes) can move and work as a ferromagnetic exchange interaction between localized moments. For this reason, the spin deviates from anti-parallel and promotes the appearance of spontaneous magnetization. This is because the movement of electrons (holes) becomes easier when the local moments are parallel to each other.
[0014]
Figure 3 shows La_0.6Sr_0.4MnO_ThreeFaraday effect of membrane (Faraday rotation angle) θ_fK (deg) is indicated. Faraday rotation angle θ_fK is proportional to the magnetization. Here, FIG. 3 shows La_0.6Sr_0.4MnO_ThreeIt shows indirectly the change in magnetization of the film. From FIG. 3, the d-orbit (e_gLaMnO, which is an antiferromagnetic material, by introducing holes into the orbit)_ThreeLa_1-xSr_xO_ThreeIt can be understood that (0 <x <1) can be converted into a ferromagnetic material.
[0015]
Further, it can be understood from FIG. 3 that the application of the external magnetic field Hc makes the localized spins parallel, and as a result, the magnetization increases. For this reason, it can be seen that the magnetic transition temperature (Curie temperature) TC also increases as the concentration of Sr increases at least when x ≦ 0.4. Similarly, the Curie temperature TC increases as the hole concentration increases. Further, as the temperature decreases, the disorder of localized spins decreases and the magnetization increases.
[0016]
In the graph of FIG. 3, the magnetization is not saturated even when the external magnetic field Hc is ± 15 KOe. This is because the localized spins are not completely parallel. The tendency for magnetization not to saturate is more pronounced when the concentration of Sr is lower. That is, as the Sr concentration is higher and the hole concentration is higher, the localized spins are more likely to be parallel and the magnetization is more likely to be saturated.
[0017]
La_1-xSr_xMnO_ThreeWhen holes are induced by applying an electric field to the film, as in the case of increasing the concentration of Sr, localized spins are likely to be parallel, local spin fluctuations are reduced, and carrier mobility is high. Become. Further, by inducing holes by applying an electric field, the magnetic transition temperature (Curie temperature) TC also changes according to the applied electric field. Therefore, by setting the magnetic transition temperature TC to an appropriate value and controlling the applied electric field, La_1-xSr_xMnO_ThreeVarious magnetic and electrical properties of the film can be switched.
[0018]
La_1-xSr_xMnO_ThreeThe film also changes its optical properties as its magnetic properties change. Therefore, the applied electric field can be controlled to change its optical characteristics.
[0019]
La_1-xSr_xMnO_ThreeAs described above, the CT gap type strongly correlated electronic material changes its magnetic property, electrical property, and optical property in various ways by controlling the hole concentration by applying an electric field. . Therefore, by appropriately controlling these characteristics, an electronic member, a semiconductor device, and the like having excellent characteristics can be obtained.
Therefore, specific embodiments of an electronic member and a semiconductor device using a CT gap type strongly correlated electronic material will be described below.
[0020]
(First embodiment)
Hereinafter, as a first embodiment of an electronic member of the present invention, a semiconductor device using a strongly correlated electronic material will be described with reference to FIGS.
As shown in FIG. 4A, this semiconductor device has an La_1-xSr_xMnO_ThreeA semiconductor layer 11, a source electrode 12 and a drain electrode 13 which are spaced apart from each other on the semiconductor layer 11, an insulating film (gate insulating film) 14 which is disposed between the source electrode 12 and the drain electrode 13, and a gate And a gate electrode 15 disposed on the insulating film 14.
[0021]
As shown in FIG. 4B, in the state where 0 V (or positive voltage) is applied to the gate electrode 15, the density and mobility of holes in the channel region in the semiconductor layer 11 are very small. Therefore, the semiconductor layer 11 maintains a high resistance state. For this reason, even if a positive voltage is applied to the source electrode 12 and a negative voltage is applied to the drain electrode 13, no current flows in the channel region between the source electrode 12 and the drain electrode 13.
[0022]
On the other hand, as shown in FIG. 4C, when a negative voltage is applied to the gate electrode 15, holes are induced in the channel region of the semiconductor layer 11, and the mobility is further increased. Becomes conductive. For this reason, a current flows from the source electrode 12 to the drain electrode 13 through the channel.
[0023]
That is, the semiconductor device having the configuration of FIG. 4 functions as a current switch that switches by controlling the gate voltage, that is, a transistor.
The operation of the current switch of this semiconductor device is the same as that of a normal FET using silicon or the like. However, the operation mechanism is completely different from the conventional FET.
[0024]
Below, La_0.7Sr_0.3MnO_ThreeAs an example, the operation mechanism of the semiconductor device having the above configuration will be described.
Fig. 5 shows the La produced by the pyrolysis method._0.7Sr_0.3MnO_ThreeThe temperature change of the resistivity R of the film is shown. The horizontal axis in FIG. 5A represents the reciprocal of the absolute temperature T, and the vertical axis represents the logarithmic value of the resistivity R. 5B represents the absolute temperature T, and the vertical axis represents the resistivity R.
[0025]
As shown in FIG. 5A, in the temperature range from around the magnetic transition temperature (Curie temperature) TC (about 350 K, 1 / T = about 0.00286) to 500 K (1 / T = about 0.002), the resistance The rate R varies linearly with respect to the inverse 1 / T of the temperature on the logarithmic graph. Therefore, the change in resistivity R in this temperature region is mainly due to carrier activation. The activation energy is about 140 meV when oxygen vacancies are present, and about 50 meV when almost no oxygen vacancies are present.
[0026]
On the other hand, the characteristics on the low temperature side (1 / T> about 0.00286) from the magnetic transition temperature TC (350 K) deviate from the activated characteristics as shown in FIG. This is because localized spins begin to align in a predetermined direction at a temperature lower than the magnetic transition temperature TC. As indicated by a solid line in FIG. 5B, the resistivity R has a value of about 0.28 Ω · cm at room temperature (about 290 K). This value is LaMnO in the bulk state_ThreeMore than an order of magnitude greater than the resistivity. This is because introduction of holes by substituting part of La with Sr is suppressed by oxygen deficiency.
[0027]
Further, when the temperature is lowered, the resistivity R has a broad peak in the vicinity of 250K. On the lower temperature side than the broad peak, the fluctuation of the localized spin decreases and the resistivity R also decreases. Furthermore, on the low temperature side, there is a temperature region having almost no temperature dependence.
[0028]
When a negative voltage is applied to the gate electrode 15, holes that are carriers are induced in the channel region of the semiconductor layer 11. If the temperature of the semiconductor layer 11 is in a state of room temperature TA lower than the magnetic transition temperature TC, the following phenomena i) to iii) occur due to the holes.
[0029]
i) Local spin fluctuations are reduced, the magnetization of the semiconductor layer 11 is changed, the magnetic transition temperature TC of the channel region is increased, and the carrier mobility is increased. For this reason, the conductivity of the channel layer increases. That is, the induction of holes reduces local spin fluctuations and raises the magnetic transition temperature TC. For this reason, as shown by a broken line in FIG. 5B, the resistivity R is shifted to the right in the graph when no voltage is applied, and the resistivity R is the same as when the temperature is relatively lowered. (The temperature TB state), and the resistivity R is greatly reduced. For this reason, the conductivity of the channel layer increases.
[0030]
ii) By applying an electric field, a magnetic field is applied to the semiconductor layer 11 and the localized spins are parallelized, so that the mobility of carriers increases and the conductivity of the channel increases. That is, in this substance, when an electric field or an external magnetic field is applied, the localized spins become parallel and the carrier mobility increases. For example, FIG. 6 shows La by applying a magnetic field._0.7Sr_0.3MnO_ThreeIt shows the change in resistivity of the film, and shows that the resistivity R decreases with the application of an external magnetic field.
[0031]
iii) The conductivity of the channel layer increases due to the increase in the carrier concentration in the semiconductor layer 11 due to the electric field. This mechanism is the same as the mechanism for increasing the conductivity of a normal FET.
[0032]
By applying a negative voltage to the gate electrode 15, the mechanisms i) to iii) described above occur in combination, so that the conductivity of the channel region increases and the semiconductor device is turned on.
[0033]
As described above, according to the semiconductor device of this embodiment, on / off can be controlled by controlling the gate voltage and controlling the magnetization. This semiconductor device has a very high carrier density when turned on. For this reason, even if light hits the channel, there is little change in carriers, and a semiconductor device that is resistant to light can be obtained. In addition, since the influence of external impurities is small, process management is facilitated, material costs and equipment are inexpensive, and manufacture is easy at a low price.
[0034]
In addition to current on / off, current can be modulated and amplified by controlling the gate voltage.
[0035]
(Second Embodiment)
In the semiconductor device of the first embodiment, the magnetization of the channel region is controlled, and thereby the on / off of the semiconductor device is controlled. By causing a magnetic transition and the accompanying metal-nonmetal transition, the semiconductor device It is also possible to control the turning on / off. Accordingly, a semiconductor device that causes magnetic transition by application of an electric field will be described below.
[0036]
FIG. 7 shows La_0.825Sr_0.175MnO_ThreeThe temperature change of resistivity R of this crystal is shown. At low temperatures, the crystals are in the metal phase and the resistivity R is low. As the magnetic transition temperature TC is approached, the resistivity R increases rapidly and exhibits a local maximum near TC. Furthermore, the resistivity R of the crystal gradually decreases as the temperature rises.
[0037]
The crystal has a magnetic transition temperature TC of 290 K, and the room temperature (crystal temperature) is slightly higher than the magnetic transition temperature TC. For this reason, in a normal temperature state, the crystal is in a high resistance state.
On the other hand, when an electric field is applied to this crystal to induce holes, the magnetic transition temperature TC rises and becomes TC ′. For this reason, it is equivalent to a relatively low temperature, and the temperature of the crystal becomes lower than the magnetic transition temperature TC '. For this reason, this crystal becomes a metal state, and its resistivity R decreases.
[0038]
Therefore, as shown in FIG._0.825Sr_0.175MnO_ThreeIs a semiconductor layer 21, a gate electrode 25 is disposed thereon via a gate insulating film 24, and the gate voltage is controlled, whereby the channel region can be transitioned between a metal state and a non-metal state.
[0039]
That is, as shown in FIG. 8B, when a positive voltage is applied to the source electrode 22, a negative voltage is applied to the drain electrode 23, and 0 V (or positive voltage) is applied to the gate electrode 25, the magnetic field of the semiconductor layer 21 is increased. The transition temperature TC is lower than room temperature (the temperature of the semiconductor layer 21). Therefore, the semiconductor layer 21 is in a semiconductor or insulator state, and the channel maintains a high resistance state. Therefore, no current flows between the source electrode 22 and the drain electrode 23, and this transistor is turned off.
[0040]
On the other hand, as shown in FIG. 8C, when a negative voltage is applied to the gate electrode 25, holes are induced in the channel region, the magnetic transition temperature TC rises, and becomes higher than the temperature of the semiconductor layer 21. For this reason, a magnetic transition occurs, and the channel region becomes a metal state and becomes a conductive state. That is, a channel is generated. Accordingly, a current flows between the source electrode 22 and the drain electrode 23. Therefore, this transistor is turned on.
[0041]
According to the semiconductor device having such a configuration, the carrier density when turned on is very high. For this reason, even if light hits the channel, there is little change in carriers, and a semiconductor device that is resistant to light can be obtained. In addition, since the influence of external impurities is small, process management is facilitated, material costs and equipment are inexpensive, and manufacture is easy at a low price.
[0042]
In addition to current on / off, current can be modulated and amplified by controlling the gate voltage.
As a semiconductor material, La_0.825Sr_0.175MnO_ThreeFor example, Nd_0.5Pd_0.5MnO_Three, La_0.825Ca_0.175MnO_ThreeEtc. can be used as well.
[0043]
(Third embodiment)
In the first and second embodiments, the present invention has been described by taking the current switch for controlling on and off of the current as an example. However, the present invention can also be applied to an optical switch. Therefore, an optical switch using a strongly correlated electronic material that causes magnetic transition by application of an electric field will be described below.
[0044]
As shown in FIG. 9, the optical switch of this embodiment has an La_0.825Sr_0.175MnO_ThreeThe semiconductor layer 31 is composed of a strongly correlated electron material such as a ground electrode 32 connected to the semiconductor layer 31, and the gate electrode 34 is disposed via a gate insulating film 33.
[0045]
When the reflectance R is small and the multiple reflection can be ignored, the transmittance of the semiconductor layer 31 is expressed by Equation 1.
[Expression 1]
T = I / I₀= (1-R)²exp (-βt)
I₀: Incident light intensity t: Semiconductor layer thickness
I: intensity of transmitted light R: reflectivity of semiconductor layer
β: Damping coefficient
[0046]
The attenuation coefficient β is expressed by Equation 2.
[Expression 2]
β = α + S_im+ S_op
α: Absorption coefficient
S_im: Scattering due to structural imperfections such as precipitates, residual pores, grain boundaries, etc. (Rayleigh scattering, Mie scattering, etc.)
S_op: Scattering based on optical anisotropy
[0047]
As shown in FIG. 9A, when the gate voltage is 0 V, the temperature of the semiconductor layer 31 is higher than the magnetic transition temperature TC, so that the semiconductor layer 31 is in the semiconductor state or the insulator state, and the reflectance R and absorption are The coefficient α is small. Therefore, (1-R) in Equation 1 is a value close to 1, and exp (−βt) is also a value close to 1. For this reason, the transmittance T is a value close to 1.
[0048]
On the other hand, as shown in FIG. 9B, when the gate voltage becomes negative, holes are induced in the semiconductor layer 31, the magnetic transition temperature TC rises, and the semiconductor layer 31 changes to a metal state. In the metallic state, the reflectance R and the absorption coefficient α are large, (1-R) is a value close to 0, and exp (−βt) is also a value close to 0. For this reason, the transmittance T is greatly reduced, and the incident light from the light source 38 can hardly pass through the semiconductor layer 21.
[0049]
Thickness t (material thickness) and S among other parameters_imDoes not depend on the metal-nonmetal transition. S_opIs small even if effective.
Therefore, the light can be switched by controlling the voltage applied to the gate electrode 24 to control the carrier concentration.
[0050]
In addition to controlling on / off of light, the intensity of transmitted light of the semiconductor layer 31 can be modulated by controlling the applied voltage.
[0051]
The semiconductor layer 31 has a very high carrier density. For this reason, there is little influence of external impurities, process management is facilitated, material costs and equipment are inexpensive, and manufacturing is easy at a low price.
[0052]
(Fourth embodiment)
The strongly correlated electronic material changes its Faraday rotation angle by controlling the carrier concentration. Therefore, an optical switch can be configured by controlling the Faraday rotation angle.
Below, the structure of the optical switch by control of a Faraday rotation angle is demonstrated.
[0053]
As shown in FIG. 10A, the optical switch of this embodiment has an La_0.825Sr_0.175MnO_ThreeA semiconductor layer 41 composed of a strongly correlated electron material such as a ground electrode 42 connected to the semiconductor layer 41, a gate electrode 44 disposed via a gate insulating film 43, and a lower surface of the semiconductor layer 41. The transparent magnetic body 45 for aligning the magnetization direction of the semiconductor layer 41, a pair of polarizing plates 46 and 47 disposed with the semiconductor layer 41 interposed therebetween, and a light source 48.
[0054]
FIG. 11 shows the strongly correlated electron material La constituting the semiconductor layer 41._1-xSr_xMnO_ThreeShows the wavelength dependence of the Faraday rotation angle. As shown in the figure, the Faraday rotation angle suddenly increases in the wavelength region of 550 nm or less, reaches a maximum near 450 nm, reverses the positive / negative sign at 400 nm or less, and further increases on the short wavelength side. Further, the Faraday rotation angle changes according to the ratio x of Sr.
Faraday rotation angle is 10^FourIt is on the order of deg / cm, which is an order of magnitude larger than YIG-based materials.
[0055]
Now, it is assumed that the temperature of the semiconductor layer 41 is slightly below the magnetic transition temperature TC. In a state where 0 V is applied to the gate electrode 44, the semiconductor layer 41 is in the semiconductor state, and the Faraday rotation angle is small. In this state, the optical axes of the pair of polarizing plates 46 and 47 are set so that light from the light source 48 is not transmitted.
[0056]
On the other hand, when a negative voltage is applied to the gate electrode 44 to induce holes in the semiconductor layer 41, the effective magnetic transition temperature TC and the magnetization of the semiconductor layer 41 increase, and the Faraday rotation angle in the semiconductor layer 51 increases. . Therefore, if the pair of polarizing plates 46 and 47 are adjusted so that light is transmitted in this state, they can function as an optical shutter or a display element.
[0057]
The polarizing plates 46 and 47 are made to transmit light from the light source 48 with 0 V applied to the gate electrode 44 and to block light from the light source 48 with negative voltage applied to the gate electrode 44. You may arrange.
[0058]
Similar to the Faraday effect, the Kerr effect is changed by controlling the carrier concentration. Therefore, as shown in FIG. 12, a light source 48 and an incident side polarizing plate 46 may be arranged so that the reflected light is detected by the output side polarizing plate 47.
[0059]
(Fifth embodiment)
In the first or second embodiment, a current switch is shown, and in the third and fourth embodiments, an optical switch is shown as a single unit. However, as shown in FIG. 13, the optical switch 51 and the current switch 52 are arranged in a matrix. Arbitrary images can be displayed by arranging the color filters and the like as necessary.
[0060]
  As shown in FIG. 14, the optical switch 51 and the current switch 52 are formed in the same substrate 54 by being electrically insulated by a dielectric 53 or the like.52The drain electrode is connected to the transparent gate electrode 55 of the optical switch, and the transparent gate electrode 55 is grounded via a resistor 56.
[0061]
According to such a configuration, by applying 0 V or a positive voltage to the gate electrode 57 of the current switch 52, the current switch 52 is turned off, and the gate electrode 55 of the optical switch 51 is pulled down to apply the ground voltage. The For this reason, the optical switch 51 is turned on, and light is transmitted through the optical switch 51. On the other hand, by applying a negative voltage to the gate electrode 57 of the current switch 52, the current switch 52 is turned on, and a positive voltage is applied to the gate electrode 55 of the optical switch 51. For this reason, the optical switch 51 is turned off and the light is blocked.
[0062]
In this way, a display device can be configured using the current switch of the first or second embodiment and the optical switch of the third or fourth embodiment.
[0063]
(Sixth embodiment)
In the above embodiment, the example in which the present invention is applied to a semiconductor device or an optical device has been described. However, the present invention can be applied to an actuator or the like. Hereinafter, embodiments applied to the actuator will be described.
FIG. 15 shows an example of an actuator. In this actuator, a plurality of semiconductor devices 62a, 62b, 62c,... Are linearly arranged on the film substrate 61 at regular intervals, and the semiconductor devices 62a, 62b, 62c,. The structure is such that one permanent magnet plate 63 is movably arranged in the information of. Each of the semiconductor devices 62a, 62b, 62c,... Includes a grounded semiconductor layer 64, a gate insulating film 65, and a gate electrode 66.
[0064]
Voltage is applied to every four gate electrodes 64 of the semiconductor devices 62a, 62b, 62c,..., Such as 0V, −2V, −3V, and −4V. Then, the semiconductor layer 64 to which the gate voltages −2V, −3V, and −4V are applied becomes stronger as the absolute value of the applied voltage becomes larger, and the semiconductor layer 64 to which the gate voltage 0V is applied becomes paramagnetic. Therefore, the permanent magnet plate 63 is most strongly attracted to the semiconductor device 62d in a ferromagnetic state and is held on the semiconductor device 62d. Next, when the applied voltage state is shifted to the right by one, the semiconductor device 62e becomes the most ferromagnetic state. As a result, the permanent magnet 63 is attracted to the semiconductor device 62e and moves thereon. Due to such an operating principle, the permanent magnet 63 moves linearly.
[0065]
FIG. 16 shows a configuration of another example of the actuator. In this actuator, a plurality of semiconductor devices 72 are arranged at regular intervals on the outer periphery of the upper surface of the disk-shaped film substrate 71, and an output shaft 73 is rotatably provided at the center of the film substrate 71. In this structure, a disk-like permanent magnet 75 is attached to the lower surface of the distal end portion of the arm 74 to which the base end portion is attached to 73. In this actuator, the permanent magnet 75 moves on the plurality of semiconductor devices 72 by the operation as described above, and the arm 74 and the output shaft 73 rotate accordingly. In this case, the output shaft 73 and the arm 74 may be omitted, and the output may be obtained from the permanent magnet 75 itself.
[0066]
As shown in FIG. 17, two semiconductor devices are provided in which a metal electrode 82, an insulating film 83, and a semiconductor layer 84 are laminated in this order on the same radius of the outer peripheral portion of the lower surface of the disc-shaped film substrate 81. The permanent magnets 86 disposed above the film substrate 81 may be attracted simultaneously by the two semiconductor devices 85.
Further, as shown in FIG. 15, a plurality of semiconductor devices 62a, 62b, 62c,... Are linearly arranged on the upper surface of the film substrate 61 at regular intervals, and these are not shown. It is good also as a structure which wound around the outer peripheral surface of this and arrange | positioned the permanent magnet to the outer side so that a movement is possible.
[0067]
(Seventh embodiment)
When the oxygen gap is not present in the C-T gap type strongly correlated electronic material or when the oxygen defect is extremely small, the maximum value of the resistivity R and the magnetic transition temperature TC substantially coincide with each other. However, in this case, the operating temperature range of the semiconductor device is limited. Therefore, it is desirable that the strongly correlated electron material contains oxygen defects as shown in Chemical Formula 1 or Chemical Formula 2.
[0068]
[Chemical 1]
  La_1-xSr_xMnO_3-y  (x: Less than 0.4)
[Chemical 2]
  Nd_1-xSr_xMnO_3-y  (x: Less than 0.4)
[0069]
Nd_1-xSr_xMnO_3-y18A and 18B show the relationship between the resistivity and the temperature when x = 0.2, 0.3, and 0.4. From these figures, Nd_1-xSr_xMnO_3-yAlso about La_1-xSr_xMnO_3-yIt can be understood that it works similarly.
Further, as shown in Chemical Formula 3 and Chemical Formula 4, Ca may be used instead of Sr.
[0070]
[Chemical 3]
  La_1-xCa_xMnO_3-y  (x: Less than 0.4)
[Formula 4]
  Nd_1-xCa_xMnO_3-y  (x: Less than 0.4)
[0071]
As shown in Chemical Formulas 5 and 6, some of the rare earths can be dissolved in other rare earths, and Sr and Ca can also be dissolved in each other.
[0072]
[Chemical formula 5]
  (LaNd)_1-xSr_xMnO_3-y  (x: Less than 0.4)
[Chemical 6]
  (LaNd)_1-xCa_xMnO_3-y  (x: Less than 0.4)
[0073]
In addition, this invention is not limited to the said embodiment, A various deformation | transformation and application are possible. For example, the CT strongly correlated electronic material of the present invention is not limited to the configuration exemplified in the above embodiment, and various other combinations can be used.
Further, the structure of the semiconductor device is not limited to the above embodiment mode. Other configurations may be adopted as long as the carrier concentration in the semiconductor layer can be appropriately controlled.
For example, as shown in FIG. 19, a metal electrode 92 is directly formed on the semiconductor layer 91, a Schottky barrier is formed between the semiconductor layer 91 and the metal electrode 92, and a carrier concentration is applied by a gate voltage applied to the metal electrode 82. May be controlled.
[0074]
【The invention's effect】
According to the electronic member of the present invention, the current switching function, the amplification function, the optical switching function, and the like are realized by using the strongly correlated electronic material layer and modulating the carrier concentration from the outside. This strongly correlated electronic material layer has a very high carrier concentration compared to other semiconductor materials. Therefore, according to the present invention, it is possible to provide a semiconductor device and an optical device that are small in the influence of exogenous impurities and the influence of light irradiation on the strongly correlated electron material layer.
[Brief description of the drawings]
FIG. 1 is a diagram of the crystal structure of MnO.
FIG. 2 (A) shows LaMnO._Three(B) is a LaSrMnO_ThreeIt is a figure which shows the electronic state of.
FIG. 3 La_0.6Sr_0.4MnO_ThreeIt is a graph which shows the relationship between the temperature of this, an external magnetic field, and a Faraday rotation angle.
4A is a diagram showing a semiconductor device according to a first embodiment of the present invention, FIG. 4B is a diagram showing an OFF state, and FIG. 4C is a diagram showing an ON state;
FIG. 5 (A) and (B) are La_0.7Sr_0.3MnO_ThreeIt is a figure which shows the relationship between temperature and resistivity.
FIG. 6 La_0.7Sr_0.3MnO_ThreeIt is a figure which shows the relationship between temperature, resistivity, and a magnetic field.
FIG. 7 La_0.825Sr_0.175MnO_ThreeIt is a figure which shows the relationship between temperature and resistivity.
8A is a diagram showing a semiconductor device according to a second embodiment of the present invention, FIG. 8B is a diagram showing an OFF state, and FIG. 8C is a diagram showing an ON state;
9A and 9B are diagrams showing an optical switch according to a third embodiment of the present invention, where FIG. 9A is a diagram showing an ON state, and FIG. 9B is a diagram showing an OFF state.
FIGS. 10A and 10B are diagrams showing an optical switch according to a fourth embodiment of the present invention, in which FIG. 10A shows an OFF state, and FIG. 10B shows an ON state.
FIG. 11 La_1-xSr_xMnO_ThreeIt is a figure which shows the relationship between the wavelength of this, a Faraday angle, and x.
FIG. 12 is a view showing a modification of the optical switch according to the fourth embodiment of the invention.
FIG. 13 is a plan view showing a state in which optical switches and current switches are arranged in a matrix.
FIG. 14 is a cross-sectional view showing a configuration in which an optical switch and a current switch are connected.
FIG. 15 is a diagram showing a configuration of an actuator according to a sixth embodiment of the invention.
FIG. 16 is a view showing a modified example of the actuator.
FIG. 17 is a view showing a modified example of the actuator.
FIGS. 18A and 18B show Nd_1-xSr_xMnO_ThreeIt is a figure which shows the relationship between temperature, resistivity, and x.
FIG. 19 is a cross-sectional view illustrating an example of a semiconductor device in which a gate electrode and a semiconductor layer are Schottky-connected.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 11 ... Semiconductor layer, 12 ... Source electrode, 13 ... Drain electrode, 14 ... Gate insulating film, 15 ... Gate electrode, 21 ... Semiconductor layer, 22 ... Source electrode, 23 ... Drain electrode, 24 ... Gate insulating film, 25 ... Gate electrode, 31 ... Semiconductor layer, 32 ... Ground electrode, 33 ... Gate insulating film, 34 ... Gate electrode 41 ... Semiconductor layer, 42 ... Ground electrode, 43 ... Gate insulating film, 44 ... Gate electrode, 51 ... Optical switch, 52 ... Current switch, 53 ... Dielectric 54 ... Semiconductor layer, 55 ... Gate electrode, 56 ... Resistance, 57 ... Gate electrode, 61 ... Film substrate, 62a-62g ... Semiconductor device, 63 ... Permanent magnet 64 semiconductor layer 65 gate insulating film 66. Gate electrode, 71 ... film substrate, 72 ... semiconductor device, 73 ... output shaft, 74 ... arm, 75 ... permanent magnet, 81 ... film substrate, 82 ... metal Electrode 83 ... Insulating film 84 ... Semiconductor layer 85 ... Semiconductor device 86 ... Permanent magnet

Claims (5)

La _1-x Sr _x MnO ₃ (0.175 ≦ x ≦ 0.4), Nd _1-x Sr _x MnO ₃ (0.2 ≦ x ≦ 0.4), La _1-x Ca _x MnO ₃ (0 .175 ≦ x <0.4), Nd _0.5 Pd _0.5 MnO ₃ , and a strongly correlated electronic material layer in which oxygen defects or oxygen defects are not present ,
A pair of electrodes connected to the strongly correlated electronic material layer to which different voltages are applied;
By applying an electric field to the strongly correlated electron material layer, the magnetization of the strongly correlated electron material layer is changed, the magnetic transition temperature is increased, the local spin fluctuation is reduced, and the current flowing between the pair of electrodes Electric field applying means for controlling
An electronic member comprising: La _1-x Sr _x MnO ₃ (0.175 ≦ x ≦ 0.4), Nd _1-x Sr _x MnO ₃ (0.2 ≦ x ≦ 0.4), La _1-x Ca _x MnO ₃ (0 .175 ≦ x <0.4), Nd _0.5 Pd _0.5 MnO ₃ , and a strongly correlated electronic material layer in which oxygen defects or oxygen defects are not present ,
A pair of electrodes connected to the strongly correlated electronic material layer to which different voltages are applied;
Applying the electric field to the strongly correlated electron material layer to apply a magnetic field to the strongly correlated electron material layer to make the localized spin parallel and controlling the electric current flowing between the pair of electrodes;
An electronic member comprising: La _1-x Sr _x MnO ₃ (0.175 ≦ x ≦ 0.4), Nd _1-x Sr _x MnO ₃ (0.2 ≦ x ≦ 0.4), La _1-x Ca _x MnO ₃ (0 .175 ≦ x <0.4), Nd _0.5 Pd _0.5 MnO ₃ , and a strongly correlated electronic material layer in which oxygen defects or oxygen defects are not present ,
A pair of electrodes connected to the strongly correlated electronic material layer to which different voltages are applied;
An electric field applying means for controlling a current flowing between the pair of electrodes by causing a metal-nonmetal transition accompanying a magnetic transition of the strongly correlated electron material layer by applying an electric field to the strongly correlated electron material layer;
An electronic member comprising: La _1-x Sr _x MnO ₃ (0.175 ≦ x ≦ 0.4), Nd _1-x Sr _x MnO ₃ (0.2 ≦ x ≦ 0.4), La _1-x Ca _x MnO ₃ (0 .175 ≦ x <0.4), Nd _0.5 Pd _0.5 MnO ₃ , and a strongly correlated electronic material layer in which oxygen defects or oxygen defects are not present ,
A pair of electrodes connected to the strongly correlated electronic material layer to which different voltages are applied;
An electric field applying means for controlling a transmittance of the strongly correlated electron material layer by causing a metal-nonmetal transition accompanying a magnetic transition of the strongly correlated electron material layer by applying an electric field to the strongly correlated electron material layer;
An electronic member comprising: La _1-x Sr _x MnO ₃ (0.175 ≦ x ≦ 0.4), Nd _1-x Sr _x MnO ₃ (0.2 ≦ x ≦ 0.4), La _1-x Ca _x MnO ₃ (0 .175 ≦ x <0.4), Nd _0.5 Pd _0.5 MnO ₃ , and the presence of oxygen defects or the absence of oxygen defects, and the Faraday effect and the Kerr depending on the applied electric field. A strongly correlated electronic material layer in which at least one of the effects changes;
An electric field applying means for controlling at least one of a Faraday rotation angle and a Kerr rotation angle by applying an electric field to the strongly correlated electronic material layer;
A magnetic layer disposed on one surface of the strongly correlated electron material layer;
Polarizing plates disposed on the light incident side and the light emitting side;
An electronic member comprising:

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