JPH0992903A - Electronic member - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable mutually changing over ferromagnetism and normal magnetism at a normal temperature, combine magnetic property with electric property or optical property, and arbitrarily control them. SOLUTION: A gate electrode 15 is arranged on a semiconductor layer 11 composed of strong correlated electron material. When carrier concentration in the semiconductor layer 11 is modulated by controlling a voltage applied to the gate electrode 15, the magnetization of the carrier is changed. By the change of the magnetization, conductivity, transmittance, Kerr effect, etc., of the semiconductor layer 11 are changed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electronic member, a semiconductor device, an optical device, and an actuator which are composed of a charge transition (C-T) gap type strongly correlated electron substance.

[0002]

2. Description of the Related 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 Laid-Open No. 07-957.
No. 54 discloses this. In the semiconductor device disclosed in this publication, by applying an electric field to control the formation of the magnetic polaron, the magnetic semiconductor layer can be transferred alternately to a ferromagnetic substance and a paramagnetic substance.

[0003]

However, the magnetic semiconductor material disclosed in this publication is EuO doped with Gd.
The operating temperature range is 100 K (absolute temperature) or less, and it is difficult to operate at room temperature. Also, in this publication,
As an application example of this semiconductor device, only an actuator that applies switching between ferromagnetic and paramagnetic properties of a semiconductor device is disclosed, and establishment of an application technique is desired.

Further, hitherto, no electronic member has been known in which the magnetic property and the electrical property or the optical property of the semiconductor layer are combined.

The present invention has been made in view of the above circumstances, and an object thereof is to provide an electronic member capable of switching magnetic characteristics at room temperature.

[0006]

In order to achieve the above object, an electronic member of the present invention comprises a strongly correlated electronic material layer and an electric field applying means for applying an electric field to the strongly correlated electronic material layer. Is characterized by.

In the strongly correlated electron material, carrier mobility, magnetization, magnetic transition temperature, transmissivity, Faraday effect, Kerr effect, etc. change according to the applied electric field. Therefore, by controlling these characteristics of the strongly correlated electron material by the electric field applying means,
It can be used as a current switch, an optical switch, a display device or the like. Further, the actuator can be configured by using the change in the magnetization of the strongly correlated electronic material.

The strongly correlated electron material layer is La _{1 -x} Sr _x M
nO _3-y , Nd _1-x Sr _x MnO _3-y , La _1-x Ca _x MnO
_3-y , Nd _1-x Ca _x MnO _3-y , Nd _1-x Pd _x Mn
O _3-y , (LaNd) _1-x Sr _x MnO _3-y , (LaNd)
_1−x Ca _x MnO _3-y , (0 ≦ x <0.5, y ≧ 0), and the like, which are charge transition gap type strongly correlated electronic substances.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION Electronic members according to embodiments of the present invention will be described below. _First , the charge transition gap type strongly correlated electron material used in the present invention will be described by taking La _{1 -x} Sr _x MnO ₃ as an example.
Among these materials, it is the d electrons (electrons in the d orbit) of Mn that control the magnetism and electrical conductivity. As shown in FIG. 1, the manganese ion Mn ^3- is surrounded by six oxygen ions O ^2- (six-coordinated).

The d-orbitals of Mn are triple degenerate orbits (t2 _g orbits) and double degenerate orbitals (e _g ) due to the influence of the O crystal field.
Orbits), and each d orbital forms an energy band. In the case of LaMnO ₃ (La ²⁺ , Mn ³⁺ , O ²⁻ ), as shown in FIG. 2A, Mn ³⁺ accommodates four electrons in the d orbit. In a usual band approximation theory, LaMnO ₃ is a metal in this state. However, in this system, electrons cannot move due to strong Coulomb interaction between electrons, and LaMnO ₃ becomes an insulator.

As a method for making this system an electric conductor,
Sometimes the double degeneracy d orbitals (e _g orbitals) that is introduced holes. For example, when a part of La ³⁺ is replaced with Sr ²⁺ , a part of Mn ³⁺ becomes Mn ⁴⁺ , and as shown schematically in FIG. There is a space available. Therefore, electrons (holes) can move, and this system becomes an electric conductor.

The e _g orbital is relatively broad due to strong hybridization with the 2p orbital of oxygen. On the other hand, the t _2g orbital has a strong locality and can be approximately considered to be a localized spin.

Since LaMnO ₃ is antiferromagnetic, t _2g
The orbital spins are parallel in opposite directions. But,
When Sr is doped, as described above, electrons (holes) can move and work as a ferromagnetic exchange interaction between localized moments. Therefore, the spin deviates from antiparallel,
Promotes the appearance of spontaneous magnetization. This is because electrons (holes) move more easily when the localized moments are parallel to each other.

FIG. 3 shows the Faraday effect (Faraday rotation angle) θ _f K (deg) of the La _0.6 Sr _0.4 MnO ₃ film. The Faraday rotation angle θ _f K is proportional to the magnetization. Here, FIG. 3 indirectly shows changes in the magnetization of the La _0.6 Sr _0.4 MnO ₃ film. 3, by introducing holes by doping Sr to d-orbital of the double degeneracy (e _g orbitals), a LaMnO ₃ is anti-ferromagnetic La _{1 over x Sr x O 3 (0 <} x
It can be understood that it can be converted into a ferromagnetic material by setting <1).

Further, it can be understood from FIG. 3 that the localized spins become parallel by the application of the external magnetic field Hc, and as a result, the magnetization increases. Therefore, it can be seen that the magnetic transition temperature (Curie temperature) TC also increases as the concentration of Sr increases, at least at x ≦ 0.4. Similarly, the Curie temperature TC rises as the hole concentration increases. Also, as the temperature decreases, the disorder of localized spins decreases and the magnetization increases.

In the graph of FIG. 3, the external magnetic field Hc is ± 15.
The magnetization is not saturated even in KOe. This is because the localized spins are not perfectly parallel. The tendency that the magnetization is not saturated is more remarkable 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 likely to be parallel and the magnetization is likely to be saturated.

Even when an electric field is applied to the La _{1 -x} Sr _x MnO ₃ film to induce holes, the localized spins are likely to be parallel to each other as in the case of increasing the Sr concentration, and the localized spins are Fluctuations are reduced and carrier mobility is increased. Further, by applying an electric field to induce holes, 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 −x} Sr _x Mn
The magnetic characteristics and electrical characteristics of the O ₃ film can be switched variously.

The La _{1 -x} Sr _x MnO ₃ film also changes its optical characteristics as its magnetic characteristics change. Therefore, the applied electric field can be controlled to change its optical characteristics.

As described above using La _{1 -x} Sr _x MnO ₃ as an example, the CT gap type strongly correlated electron substance has its magnetic properties by controlling the hole concentration by applying an electric field. The electrical properties and optical properties change variously. Therefore, by appropriately controlling these characteristics, an electronic member, a semiconductor device, etc. having excellent characteristics can be obtained. Therefore, specific embodiments of the electronic member and the semiconductor device using the CT gap type strongly correlated electron substance will be described below.

(First Embodiment) As a first embodiment of the electronic member of the present invention, a semiconductor device using a strongly correlated electron material will be described below with reference to FIGS. This semiconductor device, as shown in FIG.
Semiconductor layer 11 made of _1-x Sr _x MnO ₃ and semiconductor layer 1
1, a source electrode 12 and a drain electrode 13 that are spaced apart from each other, an insulating film (gate insulating film) 14 that is disposed between the source electrode 12 and the drain electrode 13, and a gate insulating film 1
4 and a gate electrode 15 arranged on the upper surface of the gate electrode 4.

As shown in FIG. 4B, the gate electrode 15
When 0 V (or positive voltage) is applied to the semiconductor layer 1,
The density of holes in the channel region in 1 and its mobility are very small. Therefore, the semiconductor layer 11 maintains a high resistance state. Therefore, 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.

On the other hand, as shown in FIG. 4C, when a negative voltage is applied to the gate electrode 15, the semiconductor layer 1
Holes are induced in the first channel region, the mobility thereof further increases, and the semiconductor layer 11 becomes conductive. Therefore, a current flows from the source electrode 12 to the drain electrode 13 via the channel.

That is, the semiconductor device having the structure shown in FIG. 4 functions as a current switch that switches by controlling the gate voltage, that is, a transistor. The operation itself 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 that of the conventional FET.

The operation mechanism of the semiconductor device having the above structure will be described below by taking La _0.7 Sr _0.3 MnO ₃ as an example. FIG.
The temperature change of the resistivity R of the La _0.7 Sr _0.3 MnO ₃ film prepared by the thermal decomposition method is shown in FIG. The horizontal axis in FIG. 5A is the absolute temperature T
And the vertical axis represents the logarithmic value of the resistivity R. Also,
The horizontal axis in FIG. 5B represents the absolute temperature T, and the vertical axis represents the resistivity R.
Represents

As shown in FIG. 5A, the magnetic transition temperature (Curie temperature) near TC (about 350 K, 1 / T = about 0.00286) to 500 K (1 / T = about 0.00).
In the temperature region of 2), the resistivity R changes linearly with the reciprocal 1 / T of the temperature on the logarithmic graph. Therefore, the activation of carriers is the main factor in the change in the resistivity R in this temperature region. The activation energy is about 140 meV in the presence of oxygen vacancies, and about 50 meV in the absence of oxygen vacancies.

On the other hand, the magnetic transition temperature TC (350
The characteristics on the lower temperature side (1 / T> about 0.00286) than K) deviate from the activation characteristics as shown in FIG. 5 (A). This is because the localized spins start to align in a predetermined direction at a temperature below the magnetic transition temperature TC. As shown by the 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 one digit or more higher than the resistivity of LaMnO _{3 in} the bulk state. This is because the introduction of holes by substituting a part of La with Sr is suppressed by oxygen deficiency.

When the temperature is further lowered, the resistivity R becomes 25
It has a broad peak near 0K. At a temperature lower than the broad peak, the fluctuation of the localized spin is reduced and the resistivity R is also reduced. Further, on the low temperature side, there is a temperature region having almost no temperature dependence.

When a negative voltage is applied to the gate electrode 15, holes which are carriers are induced in the channel region of the semiconductor layer 11. Assuming that the temperature of the semiconductor layer 11 is room temperature TA lower than the magnetic transition temperature TC, the holes cause the following phenomena i) to iii).

I) Fluctuations of localized spins are reduced, the magnetization of the semiconductor layer 11 is changed, the magnetic transition temperature TC of the channel region is increased, and the mobility of carriers is increased. Therefore, the conductivity of the channel layer increases. That is, fluctuations of localized spins are reduced by the induction of holes, and the magnetic transition temperature TC rises. Therefore, as indicated by a broken line in FIG. 5B, the resistivity R is in a state of being shifted to the right in the graph when no voltage is applied, and the resistivity R is the same as that when the temperature is relatively decreased. State (state of temperature TB) and resistivity R
Is greatly reduced. Therefore, the conductivity of the channel layer increases.

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 is increased and the conductivity of the channel is increased. That is, in this substance, when an electric field or an external magnetic field is applied, the localized spins become parallel and the mobility of carriers increases. For example, FIG. 6 shows changes in the resistivity of the La _0.7 Sr _0.3 MnO ₃ film due to the application of a magnetic field, and the resistivity R due to the application of an external magnetic field.
Indicates a decrease.

Iii) The conductivity of the channel layer increases due to the increase of the carrier concentration in the semiconductor layer 11 due to the electric field. This mechanism is the same as the mechanism of increasing the conductivity of a normal FET.

By applying a negative voltage to the gate electrode 15,
Since the above mechanisms i) to iii) occur in a complex manner, the conductivity of the channel region increases and the semiconductor device turns on.

As described above, according to the semiconductor device of this embodiment, by controlling the gate voltage and controlling the magnetization, it is possible to control the on / off thereof. This semiconductor device has a very high carrier density when turned on. Therefore, even if the channel is exposed to light, the change in carriers is small, and a semiconductor device that is resistant to light can be obtained. Also,
Since the influence of extrinsic impurities is small, the process control becomes easy, the material cost and the apparatus become inexpensive, and the manufacturing becomes easy at a low price.

Further, not only the on / off of the current but also the current can be modulated and amplified by controlling the gate voltage.

(Second Embodiment) In the semiconductor device of the first embodiment, the magnetization of the channel region is controlled, thereby controlling the on / off of the semiconductor device. -It is also possible to control the on / off of the semiconductor device by causing a non-metal transition. Therefore, a semiconductor device that causes a magnetic transition when an electric field is applied will be described below.

FIG. 7 shows the temperature change of the resistivity R of the crystal of La _0.825 Sr _0.175 MnO ₃ . At low temperatures, the crystals are in the metallic phase and have a low resistivity R. When approaching the magnetic transition temperature TC, the resistivity R rapidly rises and reaches a maximum in the vicinity of TC. Furthermore, the resistivity R of the crystal gradually decreases as the temperature rises.

The magnetic transition temperature TC of this crystal is 290 K, and the room temperature (temperature of the crystal) is slightly higher than the magnetic transition temperature TC. Therefore, in a normal temperature state, this crystal has 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 TC '
Becomes For this reason, the temperature becomes relatively low, and the crystal temperature becomes lower than the magnetic transition temperature TC '. Therefore, this crystal becomes a metal state and its resistivity R decreases.

Therefore, as shown in FIG.
_0.825 Sr _0.175 MnO ₃ is used as the semiconductor layer 21, the gate electrode 25 is arranged on the semiconductor layer 21 via the gate insulating film 24, and the gate voltage is controlled so that the channel region transitions between the metal state and the non-metal state. Can be made.

That is, as shown in FIG. 8B, a positive voltage is applied to the source electrode 22 and a negative voltage is applied to the drain electrode 23,
When 0 V (or a positive voltage) is applied to the gate electrode 25, the magnetic transition temperature TC of the semiconductor layer 21 is lower than room temperature (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.

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 the temperature becomes higher than the temperature of the semiconductor layer 21. Become. Therefore, magnetic transition occurs, and the channel region becomes a metal state and becomes a conductive state.
That is, a channel is created. Therefore, the source electrode 22
An electric current flows between the drain electrode 23 and the drain electrode 23. For this reason,
This transistor is turned on.

According to the semiconductor device having such a structure, the carrier density when turned on is very high. Therefore, even if the channel is exposed to light, the change in carriers is small, and a semiconductor device that is resistant to light can be obtained. Further, since the influence of external impurities is small, the process management becomes easy, the material cost and the apparatus become inexpensive, and the manufacturing becomes easy at a low price.

Further, not only the on / off of the current but also the current can be modulated and amplified by controlling the gate voltage. The semiconductor material is La _0.825 Sr.
Not limited to _0.175 MnO ₃ , for example, Nd _0.5 Pd _0.5 M
Similarly, nO ₃ , La _0.825 Ca _0.175 MnO _{3 and the} like can be used.

(Third Embodiment) In the first and second embodiments, the present invention has been described by taking the current switch for controlling the on / off of the current as an example, but the present invention is also applicable to the optical switch. Applicable. Therefore, an optical switch using a strongly correlated electron material that causes a magnetic transition when an electric field is applied will be described below.

As shown in FIG. 9, the optical switch of this embodiment has a semiconductor layer 31 made of a strongly correlated electron substance such as La _0.825 Sr _0.175 MnO ₃ and a ground electrode 32 connected to the semiconductor layer 31. And a gate electrode 34 arranged with the gate insulating film 33 interposed therebetween.

When the reflectance R is small and multiple reflections can be ignored, the transmittance of the semiconductor layer 31 is expressed by the equation 1.

## EQU1 ## T = I / I ₀ = (1-R) ² exp (-βt) I ₀ : Incident light intensity t: Semiconductor layer thickness I: Transmitted light intensity R: Semiconductor layer reflectance β : Damping coefficient

The attenuation coefficient β is expressed by the equation 2.

## EQU2 ## β = α + S _im + S _op α: Absorption coefficient S _im : Scattering due to structural imperfections such as precipitates, residual pores, and grain boundaries (Rayleigh scattering, Mie scattering, etc.) S _op : Optical difference Scattering based on directionality

As shown in FIG. 9A, the gate voltage is 0
In the state of V, the temperature of the semiconductor layer 31 is the magnetic transition temperature TC.
Since it is higher, the semiconductor layer 31 is in a semiconductor state or an insulator state, and the reflectance R and the absorption coefficient α are small. Therefore, (1-R) in the equation 1 becomes a value close to 1, and exp (-
βt) also becomes a value close to 1. Therefore, the transmittance T becomes a value close to 1.

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 transitions to the metal state. . In the metallic state, the reflectance R and the absorption coefficient α increase, and (1-R) becomes a value close to 0,
exp (-βt) also has a value close to 0. Therefore, the transmittance T is significantly reduced, and the incident light from the light source 38 can hardly pass through the semiconductor layer 21.

Among the other parameters, the thickness t (material thickness) and _Sim are independent of the metal-nonmetal transition. Further, S _op is small even if it is effective. Therefore, by controlling the voltage applied to the gate electrode 24 to control the carrier concentration, the light can be switched.

It is also possible to modulate the intensity of the transmitted light of the semiconductor layer 31 by controlling the applied voltage as well as turning the light on and off.

The carrier density of the semiconductor layer 31 is very high. Therefore, the influence of external impurities is small, the process control is easy, the material cost and the apparatus are inexpensive, and the manufacturing is easy at a low price.

(Fourth Embodiment) The strongly correlated electron substance is
By controlling the carrier concentration, the Faraday rotation angle changes. Therefore, it is possible to configure an optical switch by controlling the Faraday rotation angle.
The configuration of the optical switch by controlling the Faraday rotation angle will be described below.

The optical switch of this embodiment is shown in FIG.
(A), the semiconductor layer 41 which is composed of correlated electron materials such as La _0.825 Sr _{0 .175} MnO _3, a ground electrode 42 connected to the semiconductor layer 41, a gate insulating film 43
A pair of polarizing plates arranged on both sides of the semiconductor layer 41 and a transparent magnetic body 45 arranged on the lower surface of the semiconductor layer 41 for aligning the magnetization directions of the semiconductor layer 41. 46 and 47, and a light source 48.

FIG. 11 shows the wavelength dependence of the Faraday rotation angle of the strongly correlated electron material La _{1 -x} Sr _x MnO ₃ forming the semiconductor layer 41. As shown in the figure, the Faraday rotation angle rapidly increases in the wavelength range of 550 nm or less,
It becomes a maximum near m, the positive and negative signs are reversed at 400 nm or less, and further increases at the short wavelength side. Further, the Faraday rotation angle changes according to the ratio x of Sr. When the Faraday rotation angle is large, it is on the order of 10 ⁴ deg / cm, which is one digit or more larger than that of YIG-based materials.

Now, the temperature of the semiconductor layer 41 is the magnetic transition temperature T.
Slightly below C. When 0 V is applied to the gate electrode 44, the semiconductor layer 41 is in the semiconductor state,
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 the light from the light source 48 is not transmitted.

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. Grows. Therefore, the pair of polarizing plates 4 are arranged so that light is transmitted in this state.
By adjusting 6, 47, it is possible to function as an optical shutter or a display element.

The polarizing plate 46 is arranged so that the light from the light source 48 is transmitted while 0 V is applied to the gate electrode 44, and the light from the light source 48 is blocked while the negative voltage is applied to the gate electrode 44. , 47 may be arranged.

Similar to the Faraday effect, the Kerr effect also changes by controlling the carrier concentration. Therefore, FIG.
As shown in FIG. 2, the light source 48 and the incident side polarization plate 46 may be arranged and the reflected light may be detected by the output side polarization plate 47.

(Fifth Embodiment) In the first or second embodiment, the current switch is shown, and in the third and fourth embodiments, the optical switch is shown as a single unit. As shown in FIG. It is also possible to display an arbitrary image by arranging the optical switches 51 and the current switches 52 in a matrix, and further arranging a color filter or the like if necessary.

As shown in FIG. 14, the optical switch 51 and the current switch 52 are electrically insulated by a dielectric 53 or the like and formed in the same substrate 54. The drain electrode of the current switch 51 is an optical switch. Of the transparent gate electrode 55, and the transparent gate electrode 55 is grounded via a resistor 56.

According to such a configuration, the current switch 5
By applying 0V or a positive voltage to the second gate electrode 57, the current switch 52 is turned off, the gate electrode 55 of the optical switch 51 is pulled down, and the ground voltage is applied. Therefore, the optical switch 51 is turned on, and light passes through the optical switch 51. On the other hand, the current switch 52
The current switch 52 is turned on by applying a negative voltage to the gate electrode 57 of the optical switch 51,
A positive voltage is applied to 5. Therefore, the optical switch 51
Turns off and the light is blocked.

In this way, a display device can be constructed using the current switch of the first or second embodiment and the optical switch of the third or fourth embodiment.

(Sixth Embodiment) In the above embodiment, an example in which the present invention is applied to a semiconductor device or an optical device has been described, but it can be applied to an actuator or the like. An embodiment applied to an actuator will be described below. FIG. 15 shows an example of the actuator. In this actuator, a plurality of semiconductor devices 62a, 62b, 62c, ... Are linearly arranged at regular intervals on the film substrate 61, and the semiconductor devices 62a, 62b, 6
One permanent magnet plate 63 is movably arranged for the information 2c ... Each semiconductor device 62a, 6
.. are composed of a grounded semiconductor layer 64, a gate insulating film 65, and a gate electrode 66.

Semiconductor devices 62a, 62b, 62c ...
A voltage is applied to each gate electrode 64 every four such as 0V, -2V, -3V, -4V. Then, the semiconductor layer 64 to which the gate voltages -2V, -3V, and -4V are applied
However, the larger the absolute value of the applied voltage, the stronger the ferromagnetism becomes, 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 the ferromagnetic state, and the semiconductor device 62d
held on d. Next, when the applied voltage state is shifted rightward 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 onto it. With such an operating principle, the permanent magnet 63 moves linearly.

FIG. 16 shows the structure of another example of the actuator. In this actuator, a plurality of semiconductor devices 72 are arranged on the outer peripheral portion of the upper surface of a disk-shaped film substrate 71 at regular intervals, and an output shaft 73 is rotatably provided at the center of the film substrate 71. A disk-shaped permanent magnet 75 is attached to the lower surface of the distal end of an arm 74 having a proximal end attached to 73. In this actuator, the permanent magnet 7 is operated by the operation described above.
5 moves on the plurality of semiconductor devices 72, 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.

As shown in FIG. 17, the metal electrode 8 is formed on the same radius of the lower peripheral portion of the disk-shaped film substrate 81.
2, two insulating devices 83 and a semiconductor layer 84 are stacked in this order to provide two semiconductor devices, and the two semiconductor devices 85 are provided.
The permanent magnet 8 arranged above the film substrate 81 by
6 may be sucked at the same time. Further, as shown in FIG. 15, a plurality of semiconductor devices 62a, 62b, 62c, ... Are linearly arranged at regular intervals on the upper surface of the film substrate 61, and the semiconductor devices 62a, 62b, 62c ,. It may be configured such that it is wound around the outer peripheral surface of and the permanent magnet is movably arranged outside thereof.

(Seventh Embodiment) When oxygen defects are not present in the CT gap type strongly correlated electron material, or
When the number of oxygen defects is extremely small, the maximum value of the resistivity R and the magnetic transition temperature TC substantially match. 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 Formula 1] La _1-x Sr _x MnO _3-y (Sr: less than 0.4)

[Image Omitted] Nd _1-x Sr _x MnO _3-y (Sr: less than 0.4)

The relationship between the resistivity of Nd _{1 -x} Sr _x MnO _3-y and the temperature is shown in FIGS. 18A and 18B for x = 0.2, 0.3 and 0.4. Show. From these figures, N
Also for d _{1 -x} Sr _x MnO _3-y , La _{1 -x} Sr _x MnO
_It can be understood that it works similarly to _3-y . In addition,
As shown in Chemical formula 4, Ca may be used instead of Sr.

[0070]

[Chemical Formula 3] La _1-x Ca _x MnO _3-y (Sr: less than 0.4)

Embedded image Nd _1-x Ca _x MnO _3-y (Sr: less than 0.4)

As shown in Chemical formulas 5 and 6, rare earths can be partially dissolved in other rare earths, and Sr and Ca can also be dissolved in each other.

[0072]

Embedded image (LaNd) _1-x Sr _x MnO _3-y (Sr:
(Less than 0.4)

Embedded image (LaNd) _1-x Ca _x MnO _3-y (Sr:
(Less than 0.4)

The present invention is not limited to the above embodiment, and various modifications and applications are possible. For example, the C-T type strongly correlated electron 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 configuration of the semiconductor device is not limited to the above embodiment. Other configurations may be adopted as long as the carrier concentration in the semiconductor layer can be appropriately controlled. For example, FIG.
As shown in FIG. 9, a metal electrode 92 is directly formed on the semiconductor layer 91 to form a Schottky barrier between the semiconductor layer 91 and the metal electrode 92, and the carrier concentration is controlled by the gate voltage applied to the metal electrode 82. You may do it.

[0074]

According to the electronic member of the present invention, by using the strongly correlated electronic material layer and modulating the carrier concentration from the outside, a current switching function, an amplification function, an optical switching function and the like are realized. This strongly correlated electron material layer has a very high carrier concentration as compared with other semiconductor materials. Therefore, according to the present invention, it is possible to provide a semiconductor device and an optical device in which the influence of extrinsic impurities and the influence of light irradiation on the strongly correlated electron material layer are small.

[Brief description of drawings]

FIG. 1 is a diagram of the crystal structure of MnO.

FIG. 2A is a diagram showing an electronic state of LaMnO ₃ .
(B) is a diagram showing an electronic state of LaSrMnO ₃ .

FIG. 3 is a graph showing the relationship between the temperature of La _0.6 Sr _0.4 MnO ₃ and the external magnetic field and the 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.

5A and 5B are diagrams showing the relationship between the temperature and the resistivity of La _0.7 Sr _0.3 MnO ₃ .

FIG. 6 is a diagram showing the relationship between temperature, resistivity and magnetic field of La _0.7 Sr _0.3 MnO ₃ .

FIG. 7 is a graph showing the relationship between temperature and resistivity of La _0.825 Sr _0.175 MnO ₃ .

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.

FIG. 9 is a diagram showing an optical switch according to a third embodiment of the present invention, (A) showing an ON state and (B) showing an OFF state.

FIG. 10 is a diagram showing an optical switch according to a fourth embodiment of the present invention, (A) showing an OFF state;
(B) is a diagram showing an ON state.

FIG. 11 is a diagram showing the relationship between the wavelength of La _{1 −x} Sr _x MnO ₃ and the Faraday angle and x.

FIG. 12 is a diagram 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 present invention.

FIG. 16 is a diagram showing a modified example of the actuator.

FIG. 17 is a diagram showing a modified example of the actuator.

18 (A) and (B) are diagrams showing the relationship between temperature, resistivity and x of Nd _{1 -x} Sr _x MnO ₃ .

FIG. 19 is a cross-sectional view showing an example of a semiconductor device in which a gate electrode and a semiconductor layer are Schottky connected.

[Explanation of symbols]

11 ... Semiconductor layer, 12 ... Source electrode, 13 ... Drain electrode, 14 ... Gate insulating film, 15 ... Gate electrode, 2
DESCRIPTION OF SYMBOLS 1 ... 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, 5
DESCRIPTION OF SYMBOLS 1 ... Optical switch, 52 ... Current switch, 53 ... Dielectric material, 54 ... Semiconductor layer, 55 ... Gate electrode, 56 ... Resistor, 57 ... Gate electrode, 61. ..Film substrate, 62a
-62g ... Semiconductor device, 63 ... Permanent magnet, 64 ... Semiconductor layer, 65 ... Gate insulating film, 66 ... Gate electrode, 7
DESCRIPTION OF SYMBOLS 1 ... 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 (8)

[Claims] 1. An electronic member comprising: a strongly correlated electronic material layer; and an electric field applying means for applying an electric field to the strongly correlated electronic material layer. 2. A pair of electrodes connected to the strongly correlated electron material layer and to which different voltages are applied, wherein the electric field applying means changes the magnetization of the strongly correlated electron material layer to obtain a magnetic transition temperature. Is increased to reduce fluctuations of localized spins, and the current flowing between the pair of electrodes is controlled, The electronic member according to claim 1. 3. A pair of electrodes connected to the strongly correlated electron material layer and to which different voltages are applied, wherein the electric field applying means applies a local field to the strongly correlated electron material layer to generate localized spins. The electronic member according to claim 1, wherein the electronic members are made parallel to each other to control a current flowing between the pair of electrodes. 4. A pair of electrodes connected to the strongly correlated electron material layer and applied with different voltages, wherein the electric field applying means applies an electric field to increase the carrier concentration of the strongly correlated electron material layer. The electronic member according to claim 1, wherein the electronic member is included. 5. A pair of electrodes connected to the strongly correlated electron material layer and applied with different voltages, wherein the electric field applying means is a metal-nonmetal accompanying magnetic transition of the strongly correlated electron material layer. The electronic member according to claim 1, further comprising: an electric field applying unit that controls a current flowing between the pair of electrodes by causing a transition. 6. The strongly correlated electron material layer has a transmittance that changes according to an applied electric field, and the electric field applying means applies an electric field to the strongly correlated electron material layer to change its transmittance. It controls, The electronic member of Claim 1 characterized by the above-mentioned. 7. A magnetic material layer disposed on one surface of the strongly correlated electron material layer, and polarizing plates disposed on a light incident side and a light emitting side, wherein the strongly correlated electron material layer is an applied layer. At least one of the Faraday effect and the Kerr effect changes according to the applied electric field, and the electric field applying unit applies at least one of the Faraday rotation angle and the Kerr rotation angle by applying an electric field to the strongly correlated electronic material layer. It controls, The electronic member of Claim 1 characterized by the above-mentioned. 8. The strongly correlated electron material layer is La _{1 −x} Sr _x M
nO _3-y , Nd _1-x Sr _x MnO _3-y , La _1-x Ca _x MnO
_3-y , Nd _1-x Ca _x MnO _3-y , Nd _1-x Pd _x Mn
O _3-y , (LaNd) _1-x Sr _x MnO _3-y , (LaNd)
8. The electron according to claim 1, wherein the electron is composed of _1-x Ca _x MnO _3-y or (0 ≦ x <0.5, y ≧ 0). Element.