JP2780876B2 - Temperature sensor system using microcrystalline semiconductor thin film - Google Patents

Description

Description: TECHNICAL FIELD The present invention generally relates to a temperature sensor system, and particularly relates to a temperature measurement technique at a cryogenic temperature (a few Kelvin or sub-Kelvin) where phenomena such as superconductivity and superfluidity are observed. Has established a technology to accurately measure the temperature from the temperature to the extremely low temperature (for example, in the order of millikelvin), basic measurement of physical properties, stable excitation of superconducting magnets, and thus superconductivity and superfluidity. TECHNICAL FIELD The present invention relates to a temperature-sensitive element, a temperature sensor using a microcrystalline semiconductor thin film, a temperature sensor system using the temperature sensor, and a method for determining a temperature interpolation value thereof, so that the temperature sensor can be applied to the use of a device to which the invention is applied.

BACKGROUND ART Conventionally, for precise temperature measurement (hereinafter referred to as temperature measurement) in a wide temperature range from room temperature to extremely low temperature, a platinum resistance thermometer or the like has been widely used as a practical standard for temperature measurement.

However, these thermometers have the disadvantage that the resistance value changes in a magnetic field.

Therefore, it has been shown that highly accurate temperature measurement in a magnetic field by a platinum resistance thermometer is possible by resistance correction,
The usable temperature range is limited due to the residual resistance peculiar to metals at extremely low temperatures, and in the low temperature range of 30 Kelvin (hereinafter abbreviated as K) or less, the influence of the resistance magnetic field dependence on the temperature measurement is large, It has been practically difficult to correct the resistance value.

Therefore, a carbon glass resistance thermometer utilizing the temperature dependence of the resistance value of carbon glass is used for temperature measurement in a magnetic field.

However, even in this carbon glass resistance thermometer,
At a temperature of 4.2 K and a magnetic flux density of 8 Tesla (hereinafter abbreviated as T), there is a temperature measurement error of about 100 mK, and there is a large difference in temperature sensitivity between a low temperature region and room temperature.

That is, the carbon glass resistance thermometer is relatively effective for measuring the temperature in a magnetic field, but is not suitable for measurement in a wide temperature range.

For this reason, it is expected to realize a temperature sensor system that enables both high-precision temperature measurement in a magnetic field and high-precision temperature measurement in a wide temperature range.

By the way, the inventors of the present application have been trying to establish a temperature measurement technique in a low-temperature magnetic field that has solved high-precision temperature measurement in a magnetic field and high-precision temperature measurement in a wide temperature range as described above. Attention has been paid to microcrystalline semiconductor thin films that are promising materials, and their investigations have been conducted.

That is, the inventors of the present application manufactured a temperature sensor element using a microcrystalline semiconductor thin film (hereinafter, referred to as a temperature sensor element) and measured resistance temperature dependence and resistance magnetic field dependence.

As a result, in a microcrystalline silicon germanium thin film in a wide temperature range from extremely low temperature to room temperature, the temperature and the resistance value have a substantially predetermined relationship at almost zero magnetic field (R = aT ^b ... R: resistance value, T: temperature , A, b: arbitrary constants), which proved to be extremely promising as a temperature sensor element (see Anritsu Technical No. 67, Mar. 1994).

In addition, the inventors of the present application also measured the resistance magnetic field dependence in the low temperature range, and the change in the resistance value of the microcrystalline silicon germanium thin film in the magnetic field can be expressed by a simple function of the magnetic flux density. By correcting the property as a function of magnetic flux density, it has been found that a temperature sensor using a microcrystalline silicon germanium thin film is suitable for temperature measurement in a very low temperature magnetic field (see Japanese Patent Application Laid-Open No. 5-87641).

However, when the above-mentioned temperature sensor is put to practical use, the following items must be taken in order to achieve both high-precision temperature measurement in a magnetic field and high-precision temperature measurement in a wide temperature range. It is necessary to consider.

First, the most important thing to consider is to find the optimum combination of the conductivity type, material, composition ratio, conductivity, etc. of the microcrystalline semiconductor thin film used as the temperature sensor element from the viewpoint of the temperature dependence of the resistance value and the magnetoresistance effect. It is necessary.

Next, a second matter to be considered is how to mount the temperature sensor element.

In particular, when performing the correction according to the direction of the magnetic field in the magnetic field, when mounting the temperature sensor element, the temperature sensor element (the one on which the temperature sensor element is mounted, hereinafter the same) is directed in a predetermined direction. It must be installed.

That is, when the temperature sensor is used in a magnetic field, it is indispensable that the temperature sensor element can easily recognize from which direction the temperature sensor element is directed in the direction of the magnetic field.

In addition, there is a problem of whether the device can withstand repeated temperature cycles (from room temperature to extremely low temperature to room temperature) in a mounted state and be capable of reproducible measurement.

Next, as a third matter to be considered, the temperature characteristic of the resistance value of the temperature sensor element is strictly as described above. R = aT ^b (1) (R: resistance value, T: temperature, a, b: arbitrary constant), the problem is how to correct it.

That is, generally, even if a user of a temperature sensor obtains sample data of an actually measured value in order to know a temperature from a resistance value detected in a wide temperature range, it is necessary to perform interpolation between the sample data by the sensor user himself. And the interpolation is not easy and troublesome.

Therefore, the temperature is calculated from the resistance value using the coefficient by actually knowing the coefficient applied to a certain approximate expression.

Therefore, it is necessary that the error between the value obtained from the approximate expression and the actually measured value is as small as possible.

Further, a fourth matter to be considered is how to correct the resistance magnetic field dependence in a magnetic field.

DISCLOSURE OF THE INVENTION The present invention has been made in view of the above circumstances,
Its purpose is to measure temperature in a magnetic field with high accuracy,
Temperature-sensitive element using microcrystalline semiconductor thin film capable of achieving high-precision temperature measurement over a wide temperature range, temperature sensor, temperature sensor system using the temperature sensor, and method for determining temperature interpolated value thereof Is to provide.

According to one embodiment of the present invention, an insulating substrate, a microcrystalline semiconductor thin film provided on the insulating substrate, and the microcrystalline semiconductor thin film for passing a measurement current through the microcrystalline semiconductor thin film A pair of first electrodes connected to each other, and a pair of second electrodes connected to the microcrystalline semiconductor thin film for detecting a voltage drop induced in the microcrystalline semiconductor thin film by the measurement current A temperature-sensitive element, a non-magnetic cylindrical container that houses and seals the temperature-sensitive element together with helium gas, and is connected to each of the pair of first electrodes and the pair of second electrodes. And a temperature sensor comprising four conductors each of which is capable of being energized from the outside of the non-magnetic cylindrical container to each of the electrodes, wherein the temperature-sensing element is one of the four conductors. Of the two conductors connected to the pair of first electrodes, By being placed in close contact with and parallel to the longitudinal direction of the thermosensitive element, the directivity direction of the thermosensitive element housed inside the non-magnetic cylindrical container can be confirmed from the outside so that the thermosensitive element can be checked. A temperature sensor is provided that allows the temperature sensor to be oriented in a predetermined direction in a magnetic field.

According to another aspect of the present invention, an insulating substrate, a microcrystalline semiconductor thin film provided on the insulating substrate, the n-type silicon germanium, the composition ratio of silicon exceeds 50%, And less than 100%, the microcrystalline semiconductor thin film having a conductivity of 0.1 to 50 S / cm, and a pair connected to the microcrystalline semiconductor thin film to flow a measurement current through the microcrystalline semiconductor thin film. A temperature-sensitive element comprising: a first electrode; and a pair of second electrodes connected to the microcrystalline semiconductor thin film for detecting a voltage drop induced in the microcrystalline semiconductor thin film by the measurement current. A cylindrical container made of a non-magnetic material for housing and sealing the temperature-sensitive element together with helium gas, and connected to each of the pair of first electrodes and the pair of second electrodes, To the electrode What is claimed is: 1. A temperature sensor comprising four conductors which can be energized from the outside of a magnetic cylindrical container, wherein the temperature sensing element is connected to the pair of first electrodes of the four conductors. The two conductors are placed in close contact with each other in parallel with the longitudinal direction, so that the directivity direction of the temperature sensing element housed inside the nonmagnetic tubular container can be confirmed from the outside. A temperature sensor is provided which allows the temperature sensor to be installed so that the temperature-sensitive element is oriented in a predetermined direction in a magnetic field.

Further, according to another aspect of the present invention, there is provided a temperature interpolation value determination method and a temperature sensor system for interpolating a temperature inside and outside a magnetic field with respect to a temperature sensor using the above-described temperature sensing element.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a diagram showing the temperature dependence of the resistance of p-type and n-type Si: H and p-type and n-type SiGe: H; FIG. 2 is a graph showing the temperature dependence of the resistance of n-type Ge: H. FIG. 3 is a diagram showing the temperature dependence of the resistance value of n-type SiGe: H; FIG. 4 is a diagram showing the magnetoresistance effect of n-type SiGe: H and n-type Si: H; FIG. FIG. 6 is a diagram showing the EPMA analysis result of H; FIG. 6 is a diagram showing the EPMA analysis result of n-type SiGe: H; FIG. 7 is a diagram showing the relationship between the conductivity of n-type SiGe and the temperature dependence of resistance; FIG. 9 shows a comparison between an error caused by a conventional carbon glass temperature sensor and a Chebyshev polynomial approximation error of the temperature sensor according to the present invention; FIG. 9 is a view schematically showing a temperature sensor element used in the present invention; FIG. 11 shows the concept of the cold head of the cryostat; FIG. 12 shows the temperature dependence of resistance of the temperature sensor of the present invention and its reproducibility. FIG. 13 is a diagram showing resistance temperature dependency and reproducibility of the temperature sensor of the present invention; FIG. 14 is a diagram showing an interpolation curve obtained by Chebyshev polynomial approximation of the temperature sensor of the present invention; FIG. FIG. 16 is a diagram showing an interpolation curve obtained by Chebyshev polynomial approximation of the temperature sensor of FIG. 16; FIG. 16 is a diagram showing the resistance magnetic field dependence of the temperature sensor of the present invention; FIG. FIG. 18 shows a logarithmic plot of the resistance magnetic field dependence of the temperature sensor of the present invention; FIG. 19 shows a corrected result obtained by the least square approximation of the measurement result of FIG. FIG. 20 is a block diagram showing an overall configuration of a measurement system; FIG. 21 is a block diagram showing a schematic configuration of a temperature sensor system; and FIG. 22 is a flowchart for explaining the operation of FIG. It is.

BEST MODE FOR CARRYING OUT THE INVENTION First, some items considered in the present invention will be described.

In the present invention, one of the microcrystallized semiconductor thin films used in the temperature-sensitive element portion is the n-type conductivity type and the material is silicon germanium (SiGe) as described in the disclosure section of the invention described above. Among them, the composition ratio of silicon is more than 50% and less than 100%, and its electric conductivity is limited to 0.1 to 50 S / cm.

That is, the limitation on such a microcrystalline semiconductor thin film is based on a temperature-sensitive material for realizing temperature measurement in a wide temperature range from extremely low temperature to room temperature and capable of correcting a magnetoresistance effect in a low temperature magnetic field. In order to clarify in more detail, the grounds for these limitations are shown below.

(1) Reasons for limiting to n-type SiGe 1-1 Temperature dependence of resistance value In a temperature sensor, naturally, the problem of the temperature dependence of the resistance value of the temperature sensitive element becomes a problem. As shown in FIG.
Temperature dependence of resistance of n-type SiGe and n-type Si is almost R = aT
^α (R: resistance value, T: temperature, a, α: arbitrary constant) is excellent, but p-type SiGe has no temperature sensitivity and is not suitable for temperature measurement.
Type Si has too high a temperature sensitivity and is unsuitable for temperature measurement in a wide temperature range.

As shown in FIG. 2, the temperature dependence of the resistance value of n-type Ge is substantially R = be ^βT (R: resistance value, T: temperature, b, β: arbitrary constant)
Therefore, it is impossible to measure the temperature from extremely low temperature to room temperature with the same temperature measurement accuracy (%).

Although not shown, p-type Ge has no temperature sensitivity and cannot measure temperature.

Therefore, it can be said that n-type SiGe and n-type Si are excellent in terms of the temperature dependence of the resistance value, but n-type Si is not suitable in terms of the magnetoresistance effect described later.

FIG. 3 shows again the temperature dependence of the resistance value of the n-type SiGe. From the viewpoint of the temperature dependence of the resistance value, it is understood that the n-type SiGe is extremely excellent as a temperature sensor.

1-2 Magnetoresistive Effect FIG. 4 shows the n-type Si of n-type SiGe and the magnetoresistance effect.

Magnetoresistance n-type SiGe is in a relation of approximately ε = cB ^γ, it is possible to measure the temperature in the low temperature field by correcting the magnetoresistance effect.

Originally, the magnetoresistive epsilon semiconductor, ε = cB γ ^(γ is approximately 2, B: magnetic flux density) is expressed by the relational expression, the magnetoresistance effect of the n-type Si as shown in FIG. 4 is epsilon = cB not in the relation of ^gamma, it is difficult to correct the magnetoresistance effect of the n-type Si by this equation.

Therefore, n-type Si is not suitable for a temperature-sensitive element from the viewpoint of the magnetoresistance effect.

Accordingly, there are two types of temperature measurement: a temperature measurement in a wide temperature range from extremely low temperature to room temperature, and a temperature measurement capable of correcting the magnetoresistance effect in a low temperature magnetic field.
This is limited to n-type SiGe as a temperature-sensitive material for simultaneously realizing the two.

(2) Reason for limiting the content of Si in n-type SiGe n-type
The excellent temperature dependency of the resistance value of Si is as described above.

Therefore, it is necessary that the n-type SiGe also has the temperature dependence of the resistance value of the n-type Si, not the n-type Ge.

That is, since it is considered that Si needs to be present more than Ge, the content of Si in the n-type SiGe exceeds 50% to 100%.
%.

5 and 6 show the results of measuring the Si content of the fabricated n-type SiGe temperature sensor by EPMA.

As shown in FIGS. 5 and 6, the n-type Si
The Si contents of Ge are 85% and 92%, respectively, which are within the limits.

It has been confirmed that n-type SiGe having these composition ratios is suitable for a temperature sensor in a wide temperature range under a very low temperature and a high magnetic field.

(3) Limitation of conductivity When using n-type SiGe as a temperature-sensitive material for a temperature sensor,
It is necessary that its conductivity be in a certain range.

In other words, if the electrical conductivity is too high, the metallic properties are strengthened and the temperature dependence of the resistance value is reduced. If the electrical conductivity is too low, the semiconductor properties are enhanced and the temperature dependence of the resistance value is abnormally increased. This is because the temperature cannot be measured.

FIG. 7 shows a conductivity distribution in characteristics of a temperature sensor using n-type SiGe as a temperature-sensitive material.

As shown in FIG. 7, a temperature sensor using n-type SiGe as a temperature-sensitive material has a predetermined appropriate conductivity range of 0.1 to 50 S / c.
Temperature-sensitive materials distributed within m and outside this range are unsuitable as temperature sensors because the temperature measurement range is reduced or the temperature measurement sensitivity is reduced.

In the present invention, as a mounting form of the temperature sensor element (also referred to as a temperature sensing element), specifically, a cylindrical temperature sensor (hereinafter, referred to as a cylindrical temperature sensor covered with a cylindrical container of a nonmagnetic metal which is a cylinder made of aluminum) , A cylindrical temperature sensor).

This is because the temperature sensor element requires correction for the magnetic field, which requires that it be mounted in a predetermined direction with respect to the temperature sensor, that is, with respect to a reference in the temperature sensor. is there.

In addition, as a result of measuring the temperature dependence of the resistance value of the cylindrical temperature sensor, its reproducibility, and the dependence of the resistance value on the magnetic field,
It has been confirmed that the cylindrical temperature sensor has high resistance to the cooling cycle and has excellent reproducibility of the temperature dependency of the resistance value.

Furthermore, in the present invention, the Chebyshev polynomial approximation is performed after performing the cubic spline interpolation on the temperature dependency of the resistance value of the temperature sensor element, but the error between the approximate expression and the measured value is reduced. Thus, it has been confirmed that the conversion between the resistance value and the temperature can be performed accurately and easily.

Further, in the present invention, the resistance value of the temperature sensor element also depends on the magnetic field, so that the change in the resistance value in the magnetic field can be expressed by a simple function of the magnetic flux density, and optimization of the function is also studied. It has been confirmed that a good value can be obtained for the error after correction of the resistance magnetic field dependence.

Next, an outline of the cylindrical temperature sensor according to the present invention will be described (see FIG. 9).

 This cylindrical temperature sensor 1 has the following configuration.

That is, a microcrystalline semiconductor thin film 2 (hereinafter, referred to as a microcrystalline silicon germanium thin film) provided on a substrate.
Based on the embodiment, the microcrystalline semiconductor thin film 2 is also referred to as a microcrystalline silicon germanium thin film 2) and four electrodes connected to the thin film. The temperature-sensitive element 3 is also referred to as a temperature sensor element 3), a cylindrical container 4 made of a nonmagnetic metal for housing and sealing the temperature-sensitive element 3 together with helium gas, and a cylindrical container 4
And four conductors 5 (hereinafter, conductors 5 are also referred to as Kovar wiring pins 5 based on the embodiments) which are sealed and attached to the bottom of the thermosensitive element 3 and connected to the electrodes of the temperature sensing element 3 respectively.

A temperature sensor element 3 is formed on an insulating substrate 6 made of alumina (hereinafter, the insulating substrate 6 is also referred to as an alumina substrate 6 based on the embodiment) by a plasma CVD method.
And

The temperature sensing element 3 is an element having a four-electrode structure, of which two electrodes are current terminals 7, which are arranged opposite to both ends of the temperature sensor element 3.

The other two electrodes are voltage pickup terminals 8 arranged along the flow of current.

The current terminal 7 is in contact with the microcrystalline silicon germanium thin film 2 which is the microcrystalline semiconductor thin film 2 in a wide range in order to reduce the electric resistance of the microcrystalline semiconductor thin film 2.

The voltage pickup terminal 8 is in contact with the microcrystalline silicon germanium thin film 2 with a smaller dimension than the current terminal 7.

Note that the cylindrical container 4 is made of a nonmagnetic metal such as aluminum or copper.

Further, the four conductors 5 connected to the electrodes of the temperature-sensitive element 3 are composed of Kovar wiring pins 5, but a nonmagnetic metal such as aluminum or copper can be used.

By the way, since low temperature and cryogenic temperature are temperatures at which gas molecules become liquid, temperature measurement is often performed in a liquid. However, immersing the temperature-sensitive element 3 directly in the liquid may cause destruction of the element. As a result, the temperature sensitive element 3 must be protected in the container.

In a cryostat or the like, a circular hole is usually formed at the interface with the outside to improve heat conduction (to eliminate a temperature measurement error). It assumes a cylindrical shape.

The cylindrical container 4 is sealed with the temperature-sensitive element 3 and filled with helium gas so as to maintain a gas atmosphere in almost all the operating range of the temperature-sensitive element 3. ing.

Further, the cylindrical container 4 is provided with four legs by Kovar wiring pins 5 for electrical connection inside and outside.

The reason for using the Kovar wiring pins 5 is to make it difficult to generate thermal distortion due to a temperature difference. However, as described above, nonmagnetic metals such as aluminum and copper can be used.

In general, since cryogenic temperature measurement is often performed in a strong magnetic field, it is desirable not to use a magnetic material as the material of the cylindrical temperature sensor 1.

Therefore, for example, aluminum, copper, or the like, which is a nonmagnetic material, is used for the cylindrical container 4.

Here, the characteristic point is that the temperature sensor element 3 is brought into close contact with the two Kovar wiring pins 5 on the side connected to the current terminals 7 of the four legs of the Kovar wiring 5 in parallel with the longitudinal direction.
Is placed.

Thereby, depending on the direction of the leg of the Kovar wiring pin 5,
The orientation of the surface of the temperature sensor element 3 is known, and the correction of the dependency on the resistance magnetic field described later becomes easy.

Next, an outline of a method for determining a temperature interpolation value of the temperature sensor according to the present invention will be described.

As described above, the microcrystalline semiconductor thin film 2 typified by silicon germanium has a wide temperature range from room temperature to about 1.4K, and the temperature change of the resistance has a relationship substantially represented by the equation (1). If the temperature measurement is attempted at a very low temperature, the relationship strictly deviates from the relationship shown in Expression (1).

However, since the way of deviation is represented by a cubic curve as will be described later, the present invention employs an interpolation method using three spline functions.

Then, first, the resistance value of the cylindrical temperature sensor 1 is measured at each of the first temperature fixed point (for example, 1.4 K) and the second temperature fixed point (for example, 273 K).

In this case, some temperature fixed points (for example, a nitrogen evaporation point and a carbon dioxide gas freezing point) may be set between the first and second temperature fixed points in order to increase the accuracy of the interpolation later.

Alternatively, a method in which the interval between the first and second temperature fixed points is narrowed and the fixed points are moved may be adopted.

Next, based on the resistance values of the cylindrical temperature sensor 1 at the first and second temperature fixed points, the temperature of the cylindrical temperature sensor 1 in the resistance value range between the two temperature fixed point resistance values is determined as a function of the resistance value by a third order. Find the interpolation formula using the spline function.

Further, an interpolation value of the temperature at the resistance value between the two fixed points is obtained based on the interpolation formula.

Next, a single Chebyshev polynomial is determined using the interpolated value of the temperature.

According to the present invention, it is possible to cover with a single Tubyshev polynomial in a wide temperature range from room temperature to extremely low temperature regardless of how to set the first and second temperature fixed points.

And calculating the temperature from the last measured resistance value using a single Chebyshev polynomial.

In addition, a countermeasure must be taken for the correction of the dependence of the resistance of the microcrystalline semiconductor thin film 2 used in the magnetic field on the resistance of the microcrystalline semiconductor thin film 2 in the magnetic field.

In general, the magnetoresistance effect is approximately proportional to the product of the square of the mobility and the square of the magnetic flux density. Therefore, the microcrystalline semiconductor thin film 2 having a small mobility is smaller than the magnetoresistance effect of a metal even in a strong magnetic field.

In the magnetoresistive effect, the parallel effect (the effect when the current and the magnetic field are parallel) is much smaller than the orthogonal effect (the effect when the direct current and the magnetic field are orthogonal). .

In general, by rotating the magnetic field in a biaxial direction in a magnetic field, it is possible to know the relationship in which the relationship between the current and the magnetic field causes an orthogonal effect (the relationship in which the resistance change becomes maximum in the magnetic field).

Even when the orthogonal effect of the magnetoresistance effect is measured as a function of the magnetic field strength at a constant temperature, the relationship is not a linear relationship as described later, but is a curve relationship of a substantially quadratic function of the magnetic field strength. From this, it is possible to perform the correction using the same method as the correction of the temperature characteristics of the resistance in the zero magnetic field.

The characteristic comparison between the cylindrical temperature sensor 1 according to the present invention and a conventional carbon glass temperature sensor will be described below.

In the carbon glass temperature sensor, the maximum value of the error between the actually measured value and the value obtained by the equation is 54 mK, but in the cylindrical temperature sensor 1 of the present invention, the error was derived from the actually measured value and a single Chevshev polynomial. The maximum value of the error with the value is about 9.8 mK.

To be more specific, the cylindrical temperature sensor 1 of the present invention is suitable for Chebyshev polynomial approximation because its temperature dependence of resistance is substantially represented by the relational expression (1).

Therefore, it is possible to realize a single Chebyshev polynomial approximation in a temperature region indivisible over a wide temperature range from extremely low temperature to room temperature, which has been difficult in the past.

FIG. 8 shows the measurement error of the conventional carbon glass temperature sensor and the Chebyshev polynomial approximation error of the cylindrical temperature sensor 1 of the present invention.

In FIG. 8, the upper part shows the order of the Chebyshev coefficient used in the Chebyshev polynomial approximation, and the lower part shows the approximation error at that time.

According to FIG. 8, it can be seen that the temperature sensor of the present invention is much better in any temperature range between 1.4K, 7K, 30.8K, 129.9K, and 325K.

Next, an embodiment of the present invention based on the above outline will be described with reference to the drawings.

As shown in FIG. 9, a microcrystalline silicon germanium thin film 2 which is a microcrystalline semiconductor thin film 2 is deposited on an insulating substrate 6 by a plasma CVD method.

In this case, SiH ₄ and GeH ₄ are used as material gases, PH ₃ / H ₂ is used as a doping gas, and an alumina substrate 6 is used as the insulating substrate 6.

After the microcrystalline silicon germanium thin film 2 is deposited on the alumina substrate 6, the temperature sensor element 3, which is the temperature sensitive element 3, is manufactured according to the wafer process.

Next, a specific structure of the temperature sensor element 3 will be described.

The temperature sensor element 3 has a four-terminal structure capable of accurately measuring the resistance value of the microcrystalline silicon germanium thin film 2.

On the alumina substrate 6, a resistor made of the microcrystalline silicon germanium thin film 2 is formed.

In this case, as a specific example of the microcrystallized silicon germanium thin film 2, the above-described limiting conditions are incorporated herein.

Further, in order to investigate the influence of the metal electrode material on the distortion of the temperature sensor element 3 during cooling, the electrodes serving as the current terminal 7 and the voltage pickup terminal 8 are made of Pt / Ti or Au / Ni.
Cr is used.

The thickness of the microcrystalline silicon germanium thin film 2 is
Approximately 1 μm, and the size of the temperature sensor element 3 is 1.
It is 5 mm, 1.5 mm wide and 150 μm thick.

The resistance of the resistor at room temperature is controlled from 500Ω to 5kΩ by changing the deposition conditions.

Then, a constant current of about 1 μA flows between the electrodes 7 and 7 at both ends of the resistor, and the voltage between the electrodes 8 and 8 at the center of the resistor is measured, whereby the resistance value of the temperature sensor element 3 is obtained. .

 FIG. 10 shows a mounting diagram of the cylindrical temperature sensor 1.

As shown in FIG. 10, the size of the cylindrical temperature sensor 1 is reduced to, for example, 3.2 mm in diameter and 7.2 mm in length.

As described above, the cylindrical container 4 does not use any magnetic material in consideration of temperature measurement in a strong magnetic field.

The temperature sensor element 3 is provided with gold wiring 9, and four-terminal measurement can be performed via the Kovar wiring 5.

The temperature sensor element 3 is mounted in close contact with the longer leg of the Kovar wiring pin 5 in parallel with the longitudinal direction of the longer leg.

Further, the temperature sensor element 3 is sealed and fixed with an epoxy resin 10 having good thermal conductivity.

The epoxy resin 10 also serves as a heat sink for the temperature sensor.

Kovar wiring pin 5 is Kovar ring with glass 11
Thermally and electrically insulated from 12.

Helium gas is sealed in the cylindrical temperature sensor 1 so that liquefaction and solidification of the sealed gas itself do not occur even at an extremely low temperature.

The measurements shown below are all performed by the cylindrical temperature sensor 1
This was performed using.

FIG. 11 is a conceptual diagram of a cryostat cold head.

In this case, the temperature measurement using the six cylindrical temperature sensors is performed by a temperature measurement system combining a cryostat 110 and a superconducting magnet (SCM) 109 shown in FIG.

Liquid helium is transferred to the cryostat 110, and after the cold head 111 shown in FIG. 11 is cooled to 4.2 K and it is confirmed that the temperature is stabilized, the measurement is performed.

In the case of measurement at a predetermined temperature, the temperature is controlled by a temperature control heater 14 built in the cryostat cold head so that the measurement temperature of the carbon glass temperature sensor 13 becomes constant.

Further, the temperature of the cylindrical temperature sensor 1 using the microcrystalline silicon germanium thin film 2 at the time of temperature stabilization is measured by a rhodium iron temperature sensor 15 incorporated in the same block.

Further, for more accurate temperature measurement in a magnetic field, a capacitance temperature sensor 16 which is hardly affected by the magnetic field is incorporated.

In the measurement of the temperature dependency of the resistance value, the resistance value of the cylindrical temperature sensor 1 is measured by a four-terminal method using a measurement system shown in FIG.

The current applied from the constant current source 102 at the time of measurement by the four-terminal method is a standard resistance (1Ω-SR, 1kΩ-
The output voltages from the SRs 106 and 107 can be accurately obtained by a digital multimeter (DMM) 104.

In this case, in order to prevent the influence of the thermoelectromotive force, the applied current flows while switching between positive and negative polarities alternately.

All of these measurements are automatically performed by the measurement system shown in FIG. 20, and by using the scanner 105, all the output voltages of the six cylindrical temperature sensors 1 and the standard resistance output voltage for the cylindrical temperature sensor 1 are obtained. The output voltage of the rhodium iron temperature sensor 15, the standard resistance output voltage for the rhodium iron temperature sensor 15, the capacitance of the capacitance temperature sensor 16, the temperature of the carbon glass temperature sensor 13, and the output of the temperature control heater 14 are measured simultaneously. Personal computer
The data is read into 101 and processed.

At this time, the calorific value of the cylindrical temperature sensor 1 and the rhodium iron temperature sensor 15 is suppressed to several tens of nW or less, and the self-heating is reduced to improve the measurement accuracy.

4.2K, 10K
Six points of K, 20K, 40K, 80K and 300K are used.

In addition, in order to evaluate the reproducibility of the temperature dependency of the resistance value, the measurement is repeated five times so that the reproducibility at each measurement point is evaluated.

In the measurement of the resistance magnetic field dependence, the cryostat cold head was cooled to the cooling limit of 4.2K, and after the temperature was stabilized, the superconducting magnet (SCM) was heated at 4.2K without heating the temperature control heater 14. Exciting 109,
The resistance value at each magnetic flux density is measured.

At this time, after measuring the resistance magnetic field dependence, by measuring the temperature without generating a magnetic field, it was confirmed that there was no temperature change during the resistance magnetic field dependence measurement.

This measurement is also automatically performed by the measurement system shown in FIG. 20 including the cryostat and the superconducting magnet (SCM).

In this case, a normal temperature bore type superconducting magnet (SC
M) and a cryostat attached to its center. The measurement system includes a constant current source, a voltmeter, a scanner 10
5, temperature controller 103, capacitance LCR meter 10
8. A charging system 112 for the SCM and a level meter 113 are installed.

 Next, the measurement results in a zero magnetic field will be described.

Temperature dependence of the resistance of the cylindrical temperature sensor 1 using the temperature sensor element 3 composed of the microcrystalline silicon germanium thin film 2 (similarly in the case of the resistance magnetic field dependence measurement described later)
As a preliminary test before the measurement, a quenching resistance test of the cylindrical temperature sensor 1 is performed.

In this quenching resistance test, a cycle of quenching to liquid nitrogen and heating to room temperature is repeated 100 times, and after each cycle, the presence or absence of peeling and cracking of the helium gas-sealed portion of the epoxy resin 10 is examined.

As a result, it has been confirmed that in the cylindrical temperature sensor 1 in which the mounting form and the manufacturing conditions were optimized, none of these peeling and cracking occurred.

In this way, after the resistance of the liquid nitrogen temperature cooling cycle is confirmed, the temperature dependence of the resistance value using the cryostat and liquid helium is measured.

FIG. 12 and FIG. 13 show the temperature dependence of the resistance value of the cylindrical temperature sensor 1 having the Pt / Ti electrode and the Au / NiCr electrode, respectively, and the reproducibility thereof.

As shown in FIGS. 12 and 13, it has been confirmed that the relationship shown by the equation (1) can be substantially obtained as the temperature dependency of the resistance value in the case of the Pt / Ti electrode and the Au / NiCr electrode.

 That is, this is replaced by the relationship shown in equation (2).

(DR / dT) / (R / T) = b (2) (b: constant) Thus, when (dR / dT) / (R / T) is constant, the temperature measurement accuracy is Since δT / T is constant in the temperature range, a result is obtained that this cylindrical temperature sensor 1 is suitable for measuring the temperature from room temperature to extremely low temperature.

Regarding differences in electrode materials, only for Pt / Ti electrodes
The result is that the slope of the temperature dependence of the resistance value increases near K.

This increase is due to the cooling strain caused by the Pt / Ti electrode.
It is considered that the change is caused by a change in the resistance value.

It has been confirmed that the relationship of the expression (1) did not change before and after mounting.

As shown in FIGS. 12 and 13, the reproducibility of the five measurement results is high, and each measurement point is plotted at the same point, and the same interpolation curve is obtained in each case.

In FIGS. 12 and 13, the cubic spline function interpolates between the measurement points, and the cubic spline function is shown as an interpolation curve approximated by a Chebyshev polynomial.

In the Chebyshev polynomial approximation, each cylindrical temperature sensor 1
For each of the measurements, 16 Chebyshev coefficients from the 0th to the 15th order are obtained, and the reproducibility of the temperature dependency of the resistance value is compared based on the obtained Chebyshev coefficients.

If a temperature / resistance characteristic actually measured at a fixed temperature point is created as a look-up table (numerical table), for example, the result of smooth interpolation by spline interpolation can be used for temporary temperature measurement. In the case of the numerical table format, it may be necessary to further interpolate between them.

Therefore, in the present invention, the use of the Chebyshev polynomial and the use of the numerical table are used together.

A calculation formula from the cubic spline function interpolation to the Chebyshev polynomial approximation is shown below.

Now, the resistance value of the cylindrical temperature sensor 1 is arbitrarily measured at each of n temperature measurement points, and the ith measurement point is a first temperature fixed point, and the (i + 1) th measurement point is a second temperature fixed point.

In the cubic spline function interpolation, since the first derivative and the second derivative on the plus side and the minus side at each temperature fixed point are equal to each other, if the temperature is T and the resistance value is R, the following relational expression is established.

_{(DT / dR) i (+} ) = (dT / dR) i (-) ... (3) (d 2 T / dR 2) i (+) = (d 2 T / dR 2) i (-) ... ( 4) However, as the boundary condition, the second derivative at the extreme ends is set to 0 as follows.

(D ² T / dR ² ) ₁ (+) = 0 (5) (d ² T / dR ² ) _n (−) = 0 (6) The i-th measurement point (first temperature fixed point) and i + 1 The cubic spline function for interpolating the second measurement point (second temperature fixed point) is as follows.

T = P / Q, P = T _i-1 (R _i -R) ³ + e _i (R _i -R) ² (R-R _i-1 ) + f _i (R _i -R) (R-R _{i- 1} ) ² + T _i (R−R _i−1 ) ³ , Q = (R _i −R _i−1 ) ³ (7) where T _i and R _i are the temperature and the resistance at the ith measurement point, respectively. E _i and f _i are coefficients in the following condition: R _i ≦ R ≦ R _{i + 1} (8)

From equations (3) and (7), S = (R _i −R _i−1 ) T ″ _i−1 +2 (R _{i + 1} −R _i−1 ) T ″ _i + (R _{i + 1} −R _i) ) T ″ _{i + 1} , S / 6 = (T _{i + 1} −T _i ) / (R _{i + 1} −R _i ) − (T _i −T _i−1 ) / (R _i −R _i−1 ) (9) Also, from equations (4) and (7), e _i = 2T _i−1 + T _i − {(R _i −R _i−1 ) ² (2T ″ _i−1 + T ″ _i ) / 6} (10) f _i = T _i−1 + 2T _i − {(R _i− R _i−1 ) ² (T ″ _i−1 + 2T ″ _i ) / 6} (11) is obtained. From equations (6) and (9), (d ² T / d
R ² ) _i (i = 1, 2,..., N) is obtained, and this is expressed as (10),
By substituting into the equation (11), e _i and f _i are obtained. Further, by substituting these into the equation (7), the ith measurement point (first temperature fixed point) and the (i + 1) th measurement point are obtained. Point (second
A cubic spline function for interpolating the temperature fixed point is obtained.

Using the cubic spline function interpolation obtained in this way, sample points are calculated and Chebyshev polynomial approximation is performed. Chebyshev coefficients used for Chebyshev polynomial approximation
C _i is obtained by the following equation.

Here, A _i is an orthogonal polynomial (see equations (19) to (26)).

Further, the maximum value of the Chebyshev polynomial approximation range R _u, the minimum value as _{R L, x j = cos (} (2j-1) π / 2n) ... (13) (j = 1,2, ..., n) R _{j = {(1 + x j} ) R u + (1-x j) R L} / 2 ... (14) where (12) as indicated by the formula, and selects the interpolation value obtained by the cubic spline function, by calculating the sum of the products obtained sample points with orthogonal polynomials, Chebyshev coefficients C _i are obtained.

 The following shows the Chebyshev polynomial.

A _i (x) = cos (i cos ⁻¹ (x)) (16) A _i (x) = ₂ × A _{i− 1} (x) −A _i−2 (x) (17) x = ｛(R− R _L ) − (R _u −R)｝ / (R _u −R _L ) (18) Note that the orthogonal polynomial A _i (x) is obtained by expanding equation (17) as follows.

A ₀ (x) = 1 (19) A ₁ (x) = x (20) A ₂ (x) = 2x ² −1 (21) A ₃ (x) = 4x ³ −3x (22) ^{_{A 4 (x) = 8x 4}} -8x 2 +1 (23) A 5 (x) = 16x 5 -20x 3 + 5x ... (24) A 6 (x) = 32x 6 -48x 4 + 18x 2 -1 ... (25) A ₁₅ (x) = 16384x ¹⁵ −61440x ¹³ + 92160x ¹¹ −70400x ⁹ + 28800x ⁷ −6048x ⁵ + 560x ³ −15x… (26) In this way, a specific sample point is selected from the cubic spline function interpolation, and By performing a predetermined calculation, Chebyshev polynomial approximation is performed.

By using the Chebyshev polynomial approximation for the resistance temperature dependency as described above, the conversion between the resistance value and the temperature of the cylindrical temperature sensor 1 can be performed accurately and easily.

For this reason, the Chebyshev polynomial approximation result can be used for evaluating the reproducibility of the temperature dependence of the resistance value, and is also effective when actually measuring the temperature with the cylindrical temperature sensor 1.

14 and 15 show the reproducibility of the resistance value at 4.2 K of the cylindrical temperature sensor 1 with the Pt / Ti electrode and the Au / NiCr electrode, respectively.

The solid lines in FIGS. 14 and 15 are interpolation curves obtained by the Chebyshev polynomial approximation shown in FIGS.

As shown in FIGS. 14 and 15, the reproducibility of the results of the five measurements is within ± 10 mK at 4.2 K, which is the temperature of the rhodium iron temperature sensor 15 measuring the temperature of the cylindrical temperature sensor 1. It is almost equal to measurement accuracy.

 Next, the measurement results in a magnetic field are shown.

This is the result of measuring the resistance magnetic field dependence after confirming that the reproducibility of the resistance temperature dependence of the cylindrical temperature sensor 1 is high as described above.

FIG. 16 shows the resistance magnetic field dependence of the cylindrical temperature sensor 1 of the Pt / Ti electrode and the Au / NiCr electrode in a magnetic field of a magnetic flux density of 0 T to 7 T measured at 4.2K.

As shown in FIG. 16, the change in the resistance value of the cylindrical temperature sensor 1 due to the magnetic field excitation has a smooth curve.
As the magnetic flux density increases, the resistance value tends to increase.

FIG. 16 shows an interpolation curve obtained by interpolating between the measurement points by a cubic spline function and approximating the cubic spline function by a Chebyshev polynomial, as in the case of the resistance value temperature dependency.

In this case, 16 Chebyshev coefficients from the 0th order to the 15th order are obtained.

By correcting the change in the resistance value in the magnetic field by such interpolation, the true temperature in the extremely low temperature and high magnetic field can be accurately obtained.

FIG. 17 is a quadratic plot of the resistance magnetic field dependence.
The abscissa indicates the magnetic flux density, and the ordinate indicates the ratio of the change ratio ε of the resistance value in the magnetic field to the magnetic flux density expressed as follows.

ε = (R (B, T) −R (0, T)) / R (0, T) (27) In FIG. 17, when the resistance magnetic field dependence is represented by a straight line, the ratio of the above change ε is expressed by a quadratic expression of magnetic flux density, such as ε = aB ² + bB + c (28) (B: magnetic flux density, a, b, c: arbitrary constants), and corrects the increase in resistance value can do.

When the correction is performed using the quadratic equation as shown in FIG.
In the region of high magnetic flux density, the deviation from the correction formula becomes large, and as a result of approximation based on the interpolation formula by the least squares method, the measurement error after correction is about ± 9 mK in terms of temperature.

Next, a correction method for reducing the temperature measurement error after correction will be described.

That is, in the present invention, even in the quadratic equation correction represented by equation (28), attention is paid to the fact that the first-order term hardly contributes to the correction, and the rate of change ε is given by ε = aB ^b (a, b: arbitrary (Constant) ... (29) We tried a correction method represented by the power of the magnetic flux density.

 FIG. 18 shows a log-log plot of the resistance magnetic field dependence.

As shown in FIG. 18, the resistance magnetic field dependence is almost represented by a straight line, and it has been confirmed that this is a good approximation method.

In addition, the inclination in FIG. 18 indicates that the Pt / Ti electrode, Au / NiCr
The result is that the ratio of change ε is proportional to the 1.8th power of the magnetic flux density in both the cylindrical temperature sensors 1 of the electrodes.

FIG. 19 shows a temperature conversion of an error after correction obtained as a result of approximation based on an interpolation formula by the least square method of the measurement result of FIG.

As shown in FIG. 19, the corrected result is good,
The temperature measurement error after correction was ± 4 mK in the case of Pt / Ti electrode and ± 5 mK in the case of Au / NiCr electrode as temperature conversion, which are more than the errors after correction by the above-mentioned quadratic equation. Has been reduced.

In the measurement results, the correction amount of the resistance value by the magnetic field was almost the same in the case of the Pt / Ti electrode and the Au / NiCr electrode,
In the cylindrical temperature sensor 1 with a Pt / Ti electrode, the slope of the temperature dependence of resistance near 4.2K increases, so that the corrected temperature error is smaller than that of the Au / NiCr electrode. ing.

Further, in the present invention, a method for performing temperature correction with high accuracy has been studied, and the effectiveness of a method using Chebyshev polynomial approximation in addition to the cubic spline function interpolation shown in FIG. 16 has been confirmed.

That is, this correction method, as shown in FIG.
It performs cubic spline function interpolation and Chebyshev polynomial approximation at 4.2K.

In order to realize the Chebyshev polynomial approximation of the resistance value magnetic field dependence in any temperature range, the temperature dependence of the Chebyshev coefficient itself may be obtained.

By obtaining the temperature dependence, the cubic spline function interpolates smoothly between the measured data, and furthermore, the Chebyshev polynomial precisely approximates the magnetic field correction amount, thereby significantly improving the correction accuracy in all temperature ranges. Becomes possible.

In this case as well, similarly to the case of the zero magnetic field, a measurement method in which a numerical table is created by spline function interpolation and is used is naturally possible.

Note that, as described above, in the present invention, the cylindrical temperature sensor 1 manufactured based on the result of studying the mounting method of the temperature sensor using the microcrystalline silicon germanium thin film 2 is made of a nonmagnetic material such as aluminum and copper. A cylindrical container 4 is used, which is reduced in size to 3.2 mm in diameter and 7.2 mm in length, and is filled with helium gas.

It has been confirmed that the cylindrical temperature sensor 1 did not cause any peeling or cracking after 100 rapid cooling operations under liquid nitrogen.

The temperature dependence of the resistance value of the cylindrical temperature sensor 1 and its reproducibility were measured at six temperatures (4.2K, 10K, 20K, 40K, 80K, 300K).
As a result of the measurement in K), the temperature dependence of the resistance value substantially satisfies the expressions (1) and (2).

FIG. 21 shows a schematic configuration of the above-described temperature sensor system according to the present invention.

That is, the temperature sensor 202 corresponding to the above-mentioned cylindrical temperature sensor 1 receives supply of a predetermined current from the current source 201, and sets the first and second temperature fixed points and the predetermined temperature described above, Similarly, it is installed in relation to the magnetic field setting unit 204 for setting the first and second magnetic field strengths and the measured unit 205.

The voltmeter 206 measures the voltage from the temperature sensor 202 and outputs the voltage value to the signal processing unit 207.

The signal processing unit 207 calculates a resistance value of the temperature sensor 202 based on the voltage value from the voltmeter 206, and determines a temperature interpolation value of the temperature sensor 202 based on the resistance value as described above. Perform arithmetic processing.

The memory 208 stores the temperature interpolation value determined by the signal processing unit 207.

After that, when the temperature measurement is performed on the measured section 205, the signal processing section 207 performs the same resistance value calculation as described above, reads the temperature interpolation value from the memory 208, and performs predetermined interpolation. Thereby, the actual temperature is calculated and displayed on the display unit 209.

The temperature control unit 210 includes a heater, a cooling trap, and the like.
When the temperature control is necessary, the temperature of the measured section 205 is controlled based on the output from the signal processing section 207.

FIG. 22 is a flowchart for explaining a series of operations performed by the temperature sensor system of FIG.

That is, in step S1, it is determined whether or not the measurement is a temperature measurement in a magnetic field.

If the decision result in the step S1 is NO, the process proceeds to a step S2, in which the above-mentioned first and second temperature fixed points for measuring the temperature dependency of the resistance value are sequentially set.

If the decision result in the step S1 is YES, the first and second magnetic field intensities (including the determination of the magnetic field direction) are sequentially set in the step S3, and the process proceeds to a step S4 in which the above-described resistance value is set. A predetermined temperature is set for the magnetic field dependence measurement.

In either case, after the resistance value of the temperature sensor 202 is measured in step S5, the above-described temperature interpolation value of the temperature sensor 202 is determined in step S6.

This step S6 includes the above-mentioned (1) cubic spline interpolation S6A, (2) Chebyshev polynomial approximation S6A and (3) least squares approximation S6C, and (1) alone or In addition, (2) and (3) are executed in combination.

After the temperature interpolation value is determined in this manner, step
In S7, the temperature sensor 202 is set to the measured section 205.

Then, the resistance value measured in step S8 is
By performing the interpolation based on the temperature interpolation value determined in step S6, the required temperature display and temperature control are performed after the actual temperature of the measured section 205 is calculated.

Therefore, as described in detail above, according to the temperature sensor using the microcrystalline semiconductor thin film of the present invention, both high-precision temperature measurement in a magnetic field and high-precision temperature measurement in a wide temperature range are achieved. can do.

Regarding the mounting form of the temperature sensor element used in the present invention, the temperature sensor element is mounted in a predetermined direction with respect to the reference in the cylindrical temperature sensor, and the temperature sensor element is oriented in either direction with respect to the direction of the magnetic field. Therefore, the correction can be easily performed in a magnetic field according to the direction of the magnetic field.

Further, it has been confirmed that the cylindrical temperature sensor according to the present invention has high resistance to a cooling cycle and excellent reproducibility of the temperature dependency of the resistance value.

Further, the cylindrical temperature sensor according to the present invention can reduce the error between the approximate expression when Chebyshev polynomial approximation is performed and the actually measured value with respect to the temperature dependence of the resistance value. It can be performed precisely and easily.

Furthermore, the cylindrical temperature sensor according to the present invention can also express the resistance change in the magnetic field with a simple function of the magnetic flux density with respect to the resistance magnetic field dependence, and by optimizing the function, the resistance magnetic field can be expressed. The error after the correction of the dependency can be a very small value.

As described above, according to the temperature sensor using the microcrystalline semiconductor thin film of the present invention, the temperature can be measured in a wide temperature range in a magnetic field, which is difficult to measure with the conventional carbon glass temperature sensor, and the resistance value is high. By performing the correction of the magnetic field dependence, it is possible to obtain ± 5 mK exceeding the temperature measurement error of 100 mK in the magnetic field of the carbon glass resistance thermometer.

Furthermore, since the temperature sensor of the present invention has a constant resistance value temperature dependency (dR / R / T) / (R / T), the temperature measurement accuracy has a constant δT / T over the entire temperature range and a room temperature. Suitable for measuring temperatures from to very low temperatures.

That is, according to the temperature sensor of the present invention, it is possible to measure the temperature from room temperature to cryogenic temperature with a single sensor, showing a relationship that can be put to practical use as a high-precision temperature sensor for cryogenic temperature and high magnetic field. It has been confirmed that did not change before and after implementation.

In addition, according to the temperature sensor of the present invention, the reproducibility of the five measurements was high, being within ± 10 mK at 4.2 K, which was confirmed to be almost equal to the temperature measurement accuracy of the rhodium iron temperature sensor for temperature measurement. .

Furthermore, according to the temperature sensor of the present invention, the resistance magnetic field dependence also shows a relationship substantially satisfying the equations (28) and (29) as a measurement result at 4.2 K and 7 T as well. ± 4mK (in the case of formula (28)) and ± 9mK (in the case of formula (29))
Has been obtained.

Continuation of the front page (58) Field surveyed (Int.Cl. ⁶ , DB name) G01K 7/16 G01K 1/08 H01C 7/00

Claims (20)

(57) [Claims] An insulating substrate, a microcrystalline semiconductor thin film provided on the insulating substrate, and a microcrystalline semiconductor thin film connected to the microcrystalline semiconductor thin film for supplying a current for measurement to the microcrystalline semiconductor thin film. A temperature-sensitive element including a pair of first electrodes and a pair of second electrodes connected to the microcrystalline semiconductor thin film for detecting a voltage drop induced in the microcrystalline semiconductor thin film by the measurement current A non-magnetic cylindrical container that stores and seals the temperature-sensitive element together with helium gum therein, and is connected to each of the pair of first electrodes and the pair of second electrodes, A temperature sensor comprising: four conductors that can be energized from the outside of the nonmagnetic cylindrical container to the electrodes of the above, wherein the temperature sensing element is one of the pair of the four conductors. The two conductors connected to the first electrode are flat in the longitudinal direction. By being placed in close contact with each other, the directivity direction of the temperature-sensitive element housed inside the non-magnetic cylindrical container can be confirmed from the outside so that the temperature-sensitive element is at a predetermined position in a magnetic field. A temperature sensor, which allows a temperature sensor to be installed so as to face the direction. 2. An insulative substrate and a microcrystalline semiconductor thin film provided on the insulative substrate, comprising n-type silicon germanium, wherein the composition ratio of silicon is more than 50% and less than 100%. , Conductivity is 0.1 to 50
The microcrystalline semiconductor thin film of S / cm, a pair of first electrodes connected to the microcrystalline semiconductor thin film for flowing a measuring current to the microcrystalline semiconductor thin film, A temperature-sensitive element including a pair of second electrodes connected to the microcrystallized semiconductor thin film for detecting a voltage drop induced in the microcrystallized semiconductor thin film; and the temperature-sensitive element is housed inside together with helium gas. A cylindrical container made of a non-magnetic material to be sealed and connected to each of the pair of first electrodes and the pair of second electrodes; What is claimed is: 1. A temperature sensor comprising four conductors that can be energized from the outside, wherein the temperature-sensitive element is a longitudinal member of two conductors of the four conductors connected to the pair of first electrodes. Is placed in close contact with Setting the temperature sensor so that the directivity direction of the temperature-sensitive element housed inside the nonmagnetic cylindrical container can be confirmed from the outside so that the temperature-sensitive element faces a predetermined direction in a magnetic field. A temperature sensor characterized by allowing. 3. A method for determining a temperature interpolation value of a resistance temperature sensor using a microcrystalline semiconductor thin film, comprising the steps of: a) determining a resistance value of each resistance temperature sensor at a first temperature fixed point and a second temperature fixed point; Measuring; b) interpolating by a cubic spline function the logarithm of the temperature of the resistance temperature sensor between the two temperature fixed points as a function of the logarithm of the resistance value, based on the resistance values at the first and second temperature fixed points. Calculating a formula, wherein the first temperature fixed point is 1.4 K and the second temperature fixed point is 273 K. A temperature interpolation value of a resistance temperature sensor using a microcrystalline semiconductor thin film, wherein Decision method. 4. A resistance temperature sensor using a microcrystalline semiconductor thin film made of n-type silicon germanium, wherein the composition ratio of silicon is more than 50% and less than 100%, and the conductivity is 0.1 to 50 S / cm. A) measuring a resistance value of each resistance temperature sensor at a first temperature fixed point and a second temperature fixed point; and b) measuring the first and second temperature fixed points. Obtaining an interpolation formula based on a cubic spline function in which the logarithm of the temperature of the resistance temperature sensor between the two temperature fixed points is a function of the logarithm of the resistance value, based on the resistance value in the above. A method for determining a temperature interpolation value of a resistance temperature sensor using a microcrystalline semiconductor thin film, wherein the temperature is 1.4K and the second temperature fixed point is 273K. 5. A method for determining a temperature interpolation value of a resistance temperature sensor using a microcrystalline semiconductor thin film, comprising: a) determining a resistance value of each resistance temperature sensor at a first temperature fixed point and a second temperature fixed point; Measuring; b) interpolating by a cubic spline function using the logarithm of the temperature of the resistance temperature sensor between the two temperature fixed points as a function of the logarithm of the resistance value based on the resistance values at the first and second temperature fixed points. Calculating an expression; c) obtaining an interpolated value of the temperature at the resistance value between the first and second temperature fixed points based on the interpolation expression; and d) calculating the interpolated value obtained in the step c). Using a microcrystalline semiconductor thin film characterized in that the first temperature fixed point is 1.4K and the second temperature fixed point is 273K. A method for determining a temperature interpolation value of a resistance temperature sensor. 6. A resistance temperature sensor using a microcrystalline semiconductor thin film made of n-type silicon germanium, wherein the composition ratio of silicon is more than 50% and less than 100%, and the conductivity is 0.1 to 50 S / cm. A) measuring a resistance value of each resistance temperature sensor at a first temperature fixed point and a second temperature fixed point; and b) measuring the first and second temperature fixed points. Obtaining an interpolation formula by a cubic spline function in which the logarithm of the temperature of the resistance temperature sensor between the two temperature fixed points is a function of the logarithm of the resistance value, based on the resistance value in c), c) based on the interpolation formula Determining an interpolated value of the temperature at the resistance between the first and second temperature fixed points; and d) determining a single Chebyshev polynomial using the interpolated value determined in step c); The first temperature A method for determining a temperature interpolation value of a resistance temperature sensor using a microcrystalline semiconductor thin film, wherein a degree fixed point is 1.4K and the second temperature fixed point is 273K. 7. A method for determining an interpolation value of a magnetoresistance effect in a magnetic field of a resistance temperature sensor using a microcrystalline semiconductor thin film, comprising: a) determining a direction of a magnetic field and an intensity of the magnetic field; C.) Measuring the resistance of the resistance temperature sensor at a predetermined temperature under the intensity of the first applied magnetic field and the intensity of the second applied magnetic field; and c) measuring the resistance at the first and second applied magnetic fields. Obtaining an interpolation formula by a cubic spline function in which the magnetoresistance effect of the applied magnetic field of the resistance temperature sensor in the applied magnetic field range between the two applied magnetic fields is a function of the magnetic flux density of the applied magnetic field. A method for determining an interpolated value of a magnetoresistance effect of a resistance temperature sensor using a method. 8. A resistance temperature sensor using a microcrystalline semiconductor thin film made of n-type silicon germanium, wherein the composition ratio of silicon is more than 50% and less than 100%, and the conductivity is 0.1 to 50 S / cm. A) determining the direction of the magnetic field and the strength of the magnetic field; and b) determining a first applied magnetic field at a predetermined temperature and a second applied magnetic field. Measuring the resistance value of the resistance temperature sensor under the strength of the magnetic field; and c) determining the resistance value of the resistance temperature sensor in an applied magnetic field range between the applied magnetic fields based on the resistance values in the first and second applied magnetic fields. Obtaining an interpolation formula by a cubic spline function in which the magnetoresistance effect caused by the applied magnetic field is a function of the magnetic flux density of the applied magnetic field, and determining an interpolation value of the magnetoresistance effect of the resistance temperature sensor using the microcrystalline semiconductor thin film. 9. A method for determining an interpolated value of a magnetoresistance effect in a magnetic field of a resistance temperature sensor using a microcrystalline semiconductor thin film, comprising: a) determining a direction of a magnetic field and a strength of the magnetic field; C.) Measuring the resistance of the resistance temperature sensor at a predetermined temperature under the intensity of the first applied magnetic field and the intensity of the second applied magnetic field; and c) measuring the resistance at the first and second applied magnetic fields. Obtaining an interpolation formula by a cubic spline function in which the magnetoresistance effect of the applied magnetic field of the resistance temperature sensor in the range of the applied magnetic field between the applied magnetic fields is a function of the magnetic flux density of the applied magnetic field; and d) E) determining an interpolated value of said resistance value in an applied magnetic field between said first and second applied magnetic fields, and e) obtaining a single Chebyshev polynomial using the interpolated value obtained in step d). Using a microcrystalline semiconductor thin film consisting of Interpolated value determination method of the magnetoresistive resistance temperature sensor. 10. A resistance temperature sensor using a microcrystalline semiconductor thin film made of n-type silicon germanium, wherein the composition ratio of silicon is more than 50% and less than 100%, and the conductivity is 0.1 to 50 S / cm. A) determining the direction of the magnetic field and the strength of the magnetic field; and b) determining a first applied magnetic field at a predetermined temperature and a second applied magnetic field. Measuring the resistance value of the resistance temperature sensor under the strength of the magnetic field; and c) determining the resistance value of the resistance temperature sensor in an applied magnetic field range between the applied magnetic fields based on the resistance values in the first and second applied magnetic fields. Obtaining an interpolation formula by a cubic spline function in which the magnetoresistance effect of the applied magnetic field is a function of the magnetic flux density of the applied magnetic field; and d) an applied magnetic field between the first and second applied magnetic fields based on the interpolation formula. Interpolation of the resistance value at E) determining a single Chebyshev polynomial using the interpolated value obtained in step d), and determining an interpolated value of the magnetoresistance effect of the resistance temperature sensor using the microcrystalline semiconductor thin film. . 11. A method for determining an interpolated value of a magnetoresistive effect in a magnetic field of a resistance temperature sensor using a microcrystalline semiconductor thin film, comprising the steps of: a) determining the direction of the magnetic field and the strength of the magnetic field; C.) Measuring the resistance of the resistance temperature sensor at a predetermined temperature under the intensity of the first applied magnetic field and the intensity of the second applied magnetic field; and c) measuring the resistance at the first and second applied magnetic fields. Obtaining an interpolation formula by a least squares method in which the logarithm of the magnetoresistance effect of the resistance temperature sensor in the range of the applied magnetic field between both applied magnetic fields is a function of the logarithm of the magnetic density. A method for determining an interpolation value of the magnetoresistance effect of the resistance temperature sensor. 12. A resistance temperature sensor using a microcrystalline semiconductor thin film made of n-type silicon germanium, wherein the composition ratio of silicon is more than 50% and less than 100%, and the conductivity is 0.1 to 50 S / cm. A) determining the direction of the magnetic field and the strength of the magnetic field; and b) determining a first applied magnetic field at a predetermined temperature and a second applied magnetic field. Measuring the resistance value of the resistance temperature sensor under the strength of the magnetic field; and c) determining the resistance value of the resistance temperature sensor in an applied magnetic field range between the applied magnetic fields based on the resistance values in the first and second applied magnetic fields. Obtaining an interpolation formula by a least squares method in which the logarithm of the magnetoresistance effect is a function of the logarithm of the magnetic density, and determining an interpolation value of the magnetoresistance effect of the resistance temperature sensor using the microcrystalline semiconductor thin film. 13. An insulative substrate and a microcrystalline semiconductor thin film provided on the insulative substrate, comprising n-type silicon germanium, wherein the composition ratio of silicon is more than 50% and less than 100%. , Conductivity is 0.1 to 50
The microcrystalline semiconductor thin film of S / cm, a pair of first electrodes connected to the microcrystalline semiconductor thin film to flow a current for measurement to the microcrystalline semiconductor thin film, A temperature-sensitive element including a pair of second electrodes connected to the microcrystalline semiconductor thin film for detecting a voltage drop induced in the microcrystalline semiconductor thin film; and the pair of first electrodes of the temperature-sensitive element. A current source that supplies the measurement current to the voltage sensor, a voltage measuring unit that measures a voltage output to the pair of second electrodes of the temperature-sensitive element, and a voltage measured by the voltage measuring unit. Temperature interpolation for measuring a resistance value of each of the temperature-sensitive elements in a state where the temperature-sensitive element is set at the first and second temperature fixed points, and determining a temperature interpolation value by a cubic spline function based on the resistance values. Value determination means and Based on the voltage measured by the voltage measuring means, while measuring the resistance value of the thermosensitive element in a state where the thermosensitive element is set in the part to be measured, the resistance value is measured by the temperature interpolation value determining means. Interpolating based on the determined temperature interpolated value, comprising: a temperature calculating means for calculating the temperature of the measured portion, wherein the first temperature fixed point is 1.4K, and the second temperature fixed point is A temperature sensor system having a temperature of 273K. 14. The temperature sensor system according to claim 13, further comprising display means for displaying the temperature of said measured part calculated by said temperature calculation means. 15. The temperature sensor system according to claim 13, further comprising temperature control means for controlling a temperature of said measured part based on an output from said temperature calculation means. 16. The temperature sensor system according to claim 13, further comprising storage means for storing a temperature interpolation value determined by said temperature interpolation value determination means. 17. An insulative substrate and a microcrystalline semiconductor thin film provided on the insulative substrate, comprising n-type silicon germanium, wherein the composition ratio of silicon is more than 50% and less than 100%. , Conductivity is 0.1 to 50
The microcrystalline semiconductor thin film of S / cm, a pair of first electrodes connected to the microcrystalline semiconductor thin film to flow a current for measurement to the microcrystalline semiconductor thin film, A temperature-sensitive element including a pair of second electrodes connected to the microcrystalline semiconductor thin film for detecting a voltage drop induced in the microcrystalline semiconductor thin film; and the pair of first electrodes of the temperature-sensitive element. A current source that supplies the measurement current to the voltage sensor, a voltage measuring unit that measures a voltage output to the pair of second electrodes of the temperature-sensitive element, and a voltage measured by the voltage measuring unit. In a state where the temperature sensing element is set at a predetermined temperature under the first and second magnetic field intensities, the resistance value of the temperature sensing element is measured, and a temperature interpolation value by a cubic spline function is calculated based on the resistance value. Determine the temperature interpolation value to be determined Means, based on the voltage measured by the voltage measuring means, while measuring the resistance value of the temperature-sensitive element in a state where the temperature-sensitive element is set in the portion to be measured, and the temperature interpolation of the resistance value A temperature sensor system comprising: a temperature calculating unit that calculates the temperature of the measured section by performing interpolation based on the temperature interpolation value determined by the value determining unit. 18. The temperature sensor system according to claim 17, further comprising display means for displaying the temperature of said measured part calculated by said temperature calculation means. 19. The temperature sensor system according to claim 17, further comprising temperature control means for controlling a temperature of said measured part based on an output from said temperature calculation means. 20. The temperature sensor system according to claim 17, further comprising storage means for storing a temperature interpolation value determined by said temperature interpolation value determination means.