JPH1012937A - Dielectric ultrathin film power-supply element - Google Patents

Abstract

PROBLEM TO BE SOLVED: To increase the diffusion constant of electrons in a dielectric ultrathin film by holding a neutral dielectric ultrathin film made of a Langmuir-Blodgett film having a specified thickness by two types of metals having different work functions. SOLUTION: Al is evaporated on a slide glass 1, thus forming a lower electrode 7. Al is automatically oxidized in the air and the upper surface of the lower electrode 7 is covered with an aluminum oxide thin film 9. One to ten layers of polyimide LB monomolecular films are accumulated on the thin film 9 by a Langmuir-Blodgett(LB) method, thus applying a polyimide LB film 11 having a neutral film thickness of the order of Angstrom. In addition, Au is evaporated as an upper electrode 15 having an upper electrode terminal 13 on the polyimide LB thin film 11. By closing the switch to form a short circuit between Al and Au electrodes on the basis of the difference in work function between Al and Au of the electrodes, electronic charges are induced on the Au electrode surface, and the potential difference generated between the Al and Au electrodes causes a conduction current to flow.

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a power supply element having a metal-dielectric ultra-thin film-metal structure using a dielectric ultra-thin film, and converting thermal energy of the element itself into electric energy. Then, when the temperature of the element falls, heat flows into the element from the outside, and the temperature of the element rises.
In this way, electric power is released to the outside forever as long as the surrounding heat is present. Therefore, the device of the present invention can be used as an energy source. 2. Description of the Related Art The present invention is based on a new phenomenon that has not been discovered so far. In other words, a Langmuir layer having a thickness of several tens to several hundreds of angstroms (Å) as a dielectric ultrathin film having the structure described above.
As a result of using a Blodgit (LB) film, it has been found that this structure becomes a power source. It is not necessary that the dielectric ultrathin film is an LB film, but it is considered that such a dielectric ultrathin film cannot be formed by the conventional technology except for the LB film. The cause of the new phenomenon Electric power is generated because electrons diffuse in the dielectric ultrathin film, and thermal energy is converted into electric energy by thermal motion of the electrons. The thickness of the dielectric ultra-thin film needs to be tens to hundreds of Angstroms (Å). Problems to be Solved by the Invention The ultrathin dielectric power supply of the present invention has a small output energy. It is believed that increasing this will broaden the utility of the invention. For that purpose, it is expected to produce a dielectric ultrathin film having a large electron diffusion constant. (Embodiment) Next, an embodiment of the dielectric ultrathin film power supply element of the present invention will be described with reference to the drawings. In this embodiment, the metal I having the structure of metal I-non-polar dielectric ultra-thin film-metal II has an aluminum (Al) electrode, metal II has a gold (Au) electrode, and a non-polar dielectric ultra-thin film has a polyimide LB. It was a film. Metal II to Metal I
And the same non-polar dielectric ultra-thin film as the non-polar arachidic acid LB film and the polar TC
NQ (C ₁₅ TCNQ, 2-pentadecyl)
-7,7'-8,8'-cyanoquinodime
Similarly, a metal-polar LB heterodielectric ultrathin film-metal structure in which the LB heterofilm is overlapped with a LB heterofilm is also a dielectric ultrathin film power supply element. In FIGS. 1 and 2, first, Al having a thickness of about 2000 to 3000 ° is deposited on one surface of a microscope slide glass (size is 1/4) (1) to provide a lower electrode (5) having a lower electrode terminal (5). 7) is formed. Al is automatically oxidized in air, and the upper surface of the lower electrode (7) is made of aluminum oxide (A).
l ₂ O ₃ ). The thin film (9) is approximately 30 ° thick. L on the thin film (9)
The non-polar polyimide LB film (11) is coated by accumulating 1 to 10 polyimide LB monomolecular films by the method B. The polyimide LB film (11) has a thickness of about 4 to 40 °. Further, Au is used as an upper electrode (15) having an upper electrode terminal (13) on the polyimide LB film (11).
Dielectric ultrathin film supply device of the present invention the structure of the polyimide LB film -Au is formed - _Al-Al 2 _{O 3} film by depositing.
Polyimide (11) a nonpolar LB film and polar _Al-Al 2 _O were LB film instead of LB hetero film overlapping upper electrode (15) to the deposition of Al TCNQ ₃ film -LB of arachidic acid Although there is an example of the structure of the hetero film-Al, the characteristics of the power supply element similar to those of the example of the structure described above are shown. FIG. 3 is a circuit for measuring a current i generated from the dielectric ultrathin film power supply element sample (301) of the present invention and a voltage v measured by a voltmeter M (305).
The voltage v is a voltage (expressed by the product of the current i and the resistance value R = Ri) due to a voltage drop generated in the resistor R (304).
Since the internal resistance of the voltmeter (305) is as large as 5 _× 10 ¹³ Ω or more, when the resistor R (304) is not put into the circuit, the current i is zero and the open-circuit voltage generated from the sample (301) is You can see that it is measuring. Switch S ₁ (302)
Is a short-circuit switch that is built into the voltmeter (305), switch _S 2 (303) is intended to take into measuring circuit the resistor R (304). FIG. 4 shows the sample (3
01) is incident on the window (404) of the vacuum avalanche diode, the infrared photon is converted into an electric pulse by the vacuum avalanche diode (401), and the pulse is output through the output (411). 5 is a schematic diagram of a non-contact temperature measuring device that leads to a counter (403) and counts the number of electric pulses with the photo counter (403). To operate the vacuum avalanche diode (401), it is necessary to apply a high voltage to the vacuum avalanche diode (401) through an input (412) from a high voltage power supply (402) of -10 kV and 4 kV. The vacuum avalanche diode (401) and the sample (301) are incorporated in a Teflon frame (413) as shown in the figure, and the Teflon frame (413) is made of a copper plate (405) provided with a heater (407). The heater (407) is driven by a heater power supply (408) to increase the temperature of the sample (301). The Teflon frame (413) and the copper plate (405) are placed in a vacuum vessel (406) equipped with a vacuum pump (409). The temperature of the sample (301) is measured by a thermocouple (410) attached to the Teflon frame (413). Further, both electrodes of the sample (301) have an input resistance of 5 _× 10 ¹³ Ω or more, which is an electronic voltmeter M (305).
And the voltage generated from the sample (301) is measured. Switch _S 2 (302) is a switch for short-circuiting the sample (301) both electrodes. FIG.
The upper half of FIG. 3 measures the voltage generated from the sample (301) in FIG.
A state where the value of 00mV is obtained, open it to 1 minute after closing the switch S ₂ at the 22-minute position in the figure, then the generator increases to a by going voltage the voltmeter M (305)
FIG. After 60 minutes, a voltage of about 300 mV is generated. The photo counter of Figure 3 when opening and closing the switch S ₂ in the same manner as the voltage measurement as described above (40
The temporal change of the number n of the voltage pulses measured in 3) is shown in the lower half of FIG. The pulse number n is measured every 30 seconds for 2 seconds, and the value is indicated by a black circle in the figure. Comparing the upper and lower views of FIG. 5, the voltage pulse number n is approximately 193 during 0 to 22 seconds when a constant 900 mV is generated in the sample.
_x 10 ³ (１ ／ second), but after short-circuiting the circuit for one minute and then opening it, n gradually decreases in the process of generating and increasing voltage, and about 300 mV after 60 minutes At the point in time when the voltage is generated, the decrease amount Δn of the pulse number n is about 10 _×
10 ³ (１ ／ second). The generation of a voltage in the sample means that the electric energy (1/2) CV ² (C: capacitance of the sample, V: voltage generated from the sample) is generated, considering that the sample is a capacitor. Indicates that
The decrease in n indicates a decrease in infrared photons incident on the window W (404) of the vacuum avalanche diode (401) from the surface of the sample (301) in FIG. 3, and this decrease indicates a decrease in the temperature of the sample. That is, this indicates that heat energy was converted to electric energy in the sample. In order to evaluate the outline of the temperature drop, an experiment shown in FIG. 6 was performed. That is, in the non-contact temperature measuring device of FIG. 4, the heater R (407) is heated by the power supply (408) to raise the temperature of the sample (301) by 1 to 2 ° C. above room temperature, and the power supply (408) To stop heating the sample (301), and in the process of allowing the sample (301) to cool down naturally,
The temperature of the sample (301) and the photo counter (403)
The dependence of the voltage pulse on the elapsed time with the number n of the measured voltage pulses was measured and shown as straight lines L and L ′ in the figure. The relationship between the temperature of the sample (301) and the number n of voltage pulses is obtained from the straight lines L and L ', and this is shown in the inset of FIG. The sample (301)
Was measured with a thermocouple (410). The sample (30
Since 1) is contained in the vacuum vessel (406), the natural cooling rate is very slow. From the results shown in FIG. 6, the decrease of Δn = 10 _× 10 ³ (１ ／ second) shown in FIG.
This corresponds to a temperature drop of 6 ° C. Here, the magnitude of the temperature drop will be evaluated. First, as shown in FIG. 5, a voltage of 300 mV was generated in the sample. Here, the capacitance C of the sample is C = 0.15 μF. Generally, the specific heat of plastic is about 1 [Jg ^-1 K ^-1 ] and the specific gravity is also about 1. The volume V of the LB film used herein is ^{_{V = 0.2 x 4.2 x 10 -}} 7 [cm 3] (2) a (area of the sample is 0.2 ^[cm 2], LB film monomolecular (The thickness of one monolayer is 4.2 [Å] since 10 films are accumulated in layers.) If the thermal energy shown in the equation (1) is taken from the LB film, the temperature drop ΔT of the LB film is calculated by the following equation. Here _{G s} and G is the specific heat and density of the polyimide LB ^films, and to the ^{1Jg -1 K} -1 1 and. The heat conduction around the LB film is quite complicated, and there are also deposition electrodes.
Considering that the entire sample is heated in the temperature evaluation, the evaluation temperature drop value obtained by the equation (3) roughly explains 0.026 ° C. obtained in the experiment. FIG. 7 is an experimental result showing an integrated value of the power emitted from the sample (703) of the dielectric ultrathin film power supply device of the present invention. The power measurement circuit is shown in FIG. 1 _× 10 ¹¹ Ω resistor R (70
1) is always connected to both electrodes of the sample, so long as a voltage is generated between both electrodes of the sample, the current i
01). Set switch S (704) to 8 per day
Close the sample for 10 hours with a voltmeter M (702) (703)
, That is, the voltage generated at the resistor R (701). Since the internal resistance of the voltmeter M (702) is as large as 5 _× 10 ¹³ Ω or more, all the current i may pass through the resistance R (701). An example of a measurement on one day in March 1996 is shown in FIG. As can be seen, the generated voltage fluctuates at the beginning of the measurement, but eventually becomes constant. Although the measurement is performed at room temperature, when the room temperature is almost constant, the generated voltage hardly changes. It is assumed that a voltage having the magnitude as shown in FIG. 2 measured continuously during the night when the voltage is not measured continues until the next measurement, and the integrated power consumed by the resistor R (701) is calculated. The graph shown is FIG. As a result of a continuous test for about one year and three months, the integrated value W of the power emitted from this sample is W ≒ 1 _× 10 ⁻⁵ [J] (4) This value is a value (1) that can be stored in the sample (703). / 2) Cv ²
(This sample is a capacitor, C is about 0.14 μF in the capacity of the sample, and v is about 0.3 in the open voltage generated from the sample.
V). This electric energy is consumed by the resistor R (701) and becomes heat. 7 in FIG.
Although the generated power is large from Monday to September, in Japan, the temperature is high in summer in this season, and when the temperature is high, the generated voltage increases and the generated power increases. The cause of the voltage generation is considered to be that the electrons induced at the Au electrode by the difference between the work functions of Al and Au or the polarization charge of the polar dielectric ultra-thin film diffuse in the dielectric ultra-thin film. It is considered that the constant increases and the generated voltage increases. Similar releases of such electrical energy from samples continue today.
It is considered that the dielectric-to-ultra-thin film power supply element will last forever unless destroyed. As described with reference to FIG. 5, it is considered that the dielectric ultrathin film power supply element of the present invention is an element having a function of a converter for converting thermal energy into electric energy. FIG. 8 shows the circuit of FIG.
The current i flowing through this resistor and the generated voltage were measured by changing the value of 1). The resistance R (701) is 10 ⁸ Ω,
In the case of 10 ⁹ Ω and 10 ¹⁰ Ω, since the generated voltage is small and the current is constant, the characteristics of the constant current source are shown.
^{At 11} Ω, the generated voltage increases and the current decreases. 8 will be described with reference to FIG. FIG. 9 is an energy band diagram of a cross-sectional view of an element using a nonpolar polyimide LB film as a thin film of the dielectric ultra-thin film power supply element of the present invention described in claim (3). The switch S is determined by the difference between the work functions of Al and Au (ψ ₁ −φ ₂ , about 1 eV).
When (908) is closed and the Al and Au electrodes are short-circuited, an electron charge -Q (903) is induced on the Au electrode surface. The electrons forming the electron charge -Q (903) are polyimide L
The diffusion current I _D (905) is generated by diffusing in the B film (901). On the other hand, since the potential of the Au electrode becomes positive due to the diffusion of the electrons, the conduction current I _C is generated by the potential difference generated between the Al and Au electrodes. (907) flows. Further, the current I _R (910) also flows through the resistor R (905) due to this potential difference, but when the generated voltage becomes constant, a steady state occurs, and the following relationship occurs between the currents. I _D = _I C ₊ I R (5) but within the generated voltage is smaller ignore _{I C I D} ≒ _I R (6) i.e. said current _I R that is released to the outside (910) of the diffusion current _{I D} (906). On the other hand, diffusion is a phenomenon that does not depend on an electric field, and is considered to be due to the electron charge -Q (903) induced by a difference in work function between Au and Al. Therefore, the resistor R having a small generated voltage
When (905) = 10 ⁸ , 10 ⁹ , and 10 ¹⁰ Ω, it indicates the property of a constant current source. When the generated voltage is high, decreases from current I _R diffusion current I _D to be measured is not negligible conduction current I _C of the equation (5). The resistance of the sample used for the measurement in FIG. 8 is about 10 ¹⁰ to 10 ¹¹ Ω. As described above, the dielectric ultra-thin film power supply device of the present invention has a metal I- in which a non-polar dielectric ultra-thin film having a thickness of several tens to several hundreds of mm is sandwiched between metals having different work functions (eg, Al and Au). Non-polar dielectric ultra-thin film-metal II structure or structure in which a polar dielectric ultra-thin film is sandwiched between the same kind of metals Metal-polar dielectric ultra-thin film-MIM (metal-insulator-meta)
l). Such a very thin nonpolar dielectric film and a film having not only a very thin but also extremely large polarization do not exist at present except for the Langmuir-Blodgett (LB) film. If a dielectric ultrathin film having performance replacing the LB film is made in the future, it will be used instead of the LB film.
Although the energy that can be emitted from the dielectric ultrathin film power supply device of the present invention is relatively small at present, if the energy is increased by making improvements such as increasing the diffusion constant, the application will be further expanded and the energy problem of humankind will be increased. It is thought to be useful for the solution. Further, the dielectric ultra-thin film power supply element of the present invention can absorb the surrounding heat energy without any action from the outside and emit electric energy permanently. Note that the dielectric ultrathin film power supply element of the present invention may operate as a current source in some cases.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic plan view of an embodiment of a dielectric ultra-thin film power supply device according to the present invention, FIG. 2 is a sectional view taken along line 11-11 of FIG. 1, and FIG. FIG. 4 is a circuit diagram for measuring a voltage generated from the ultra-thin film power supply element. FIG. 4 is a schematic diagram of a non-contact temperature measuring device for measuring a temperature drop of the element at the same time that a voltage is generated from the dielectric ultra-thin film power supply element in FIG. FIG. 4 is a diagram showing the temperature drop of the device of the present invention by measuring infrared photons generated from the dielectric ultra-thin film power supply device of the present invention based on the measurement results shown in FIG. 4, and FIG. 6 is a diagram showing the magnitude of the temperature drop measured in FIG. Figure that roughly defines
FIG. 7 is a view showing that the dielectric ultra-thin film power supply element of the present invention continuously emits electric energy for one year and three months (currently continues to emit electric energy), and FIG. 8 is a dielectric substance of the present invention. FIG. 9 is a view showing that the ultra-thin film power supply element serves as a current source, and FIG. 9 is an energy band diagram for explaining that the dielectric ultra-thin film power supply element of the present invention serves as a current source.

Claims (1)

Claims: (1) Metal I-Non-polar dielectric ultra-thin film-Metal II in which a non-polar dielectric ultra-thin film having a thickness on the order of Angstroms (Å) is sandwiched between two metals having different work functions. Ultra-thin dielectric power supply element having the structure described above. (2) Metal-heterodielectric ultrathin film-metal thin film in which a heterodielectric ultrathin film obtained by laminating a nonpolar dielectric ultrathin film and a polar dielectric ultrathin film having a thickness on the order of angstrom is sandwiched by the same kind of metal Ultra-thin dielectric power supply device having a structure. (3) The ultra-thin dielectric thin film power supply device according to claim 1 or 2, wherein the non-polar ultra-thin dielectric film or the ultra-thin hetero dielectric thin film uses a Langmuir-Blodgett film. element.