JPH0666486B2 - Recrystallized film for Hall effect element and method of manufacturing the same - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a recrystallized film for a Hall effect element and a method for manufacturing the same, and particularly to a Hall effect element that improves the performance of the recrystallized film and does not have directional magnetoelectric properties. TECHNICAL FIELD The present invention relates to a recrystallized film for use and a manufacturing method thereof.

[Conventional technology]

As the material of the Hall effect element or the magnetic resistance effect _{element, I n Sb, G a A} s, although Si or the like is used, I _n Sb deposited film is a compound semiconductor Among these materials, at room temperature Also has a high mobility of about 20000 to 50000 cm ² / Vsec.
The I _n Sb film can be obtained a method vacuum deposition, by a sputtering method or a chemical vapor deposition method, etc., it is practically duty. In particular, by using the recrystallization method for these films, the mobility of the film after recrystallization can be dramatically improved to about 2 to 20 times that of the film before recrystallization.

In the recrystallization method of the conventional I _n Sb film having a thickness of about 200 Å S
The _i O film or I _n Sb film coated with I _n2 O ₃ film, in or in a vacuum in an inert gas (Ar gas), or melted by the proximity operation of the electron beam method or a hot wire, similarly S _i the O film or I _n2 O ₃ I _n Sb film coated with film under the same atmosphere as described above, were subjected to melt uniformly heated.

[Problems to be Solved by the Invention]

However, in the former electron beam scanning method or melt method using a scanning heated by the hot wire, as shown in FIG. 8, the recrystallization film Yan connexion I _n Sb in the scanning direction, a single metal I _n and Sb There were linearly arranged in succession, a linear metal having a large number of short-circuit electrode acts to increase the magnetic resistance in the I _n Sb film is shown many phenomena arranged in parallel. If a Hall element in which a current I is flowed in a direction perpendicular to a linear single metal (I _n or Sb) arranged in parallel is manufactured, the arrangement shown in FIG. 8 is obtained. This configuration is suitable for use as a magnetoresistive element, but not as a Hall effect element. In FIG. 8, B represents the magnetic flux density to be applied, and the arrow direction represents the magnetic field application direction.

The latter method of melting, i.e., a method of melting, I _n Sb film is uniformly heated by uniformly heating the entire I _n Sb film coated with S _i O film or I _n2 O ₃ film Therefore, as shown in FIG. 9, dendritic crystals of I _n Sb containing I _n or Sb at the boundary surface, precipitates, obliquely arranged with respect to the direction of the main current I. In the vicinity of the I _n or Sb metal and this precipitate,
When the magnetic field is applied, the current path is bent, and as a result, the current path is extended, so that the resistance increases with respect to the main current I. Then, it is equivalent to that the electrode E _H provided at the midpoint of the side surface of the Hall element is electrically attached at a position deviated from the midpoint due to the action of the metal in the diagonally parallel arrangement.

Therefore, the device is sensitive to magnetic fields in one direction,
Since it is insensitive to the magnetic field in the other direction, it becomes a so-called directional magnetoelectric element. Thus, the dendrite I _n Sb is deposited obliquely arranged with respect to the main current is hard to say that the preferred Hall effect element. In FIG. 9, the output voltage V _out = V _H + V _M as shown by the solid line in FIG. 10 appears across the electrode E _H corresponding to the Hall voltage electrode. The reason for this is that the Hall voltage V _H shown by the alternate long and short dash line and the voltage drop V _M due to the magnetoresistive effect shown by the broken line overlap each other, so that a characteristic sensitive to a magnetic field in one direction (magnetic flux density = B) is exhibited. This is to show.

Above As mentioned, although improved mobility of I _n Sb raw material film by recrystallization methods were attempted for hole electrode output voltage V _out is the magnetic flux density B for the magnetoresistance effect appearing along with this Since it does not show linearity, it was difficult to produce a Hall element material having good linearity by the recrystallization method.

An object of the present invention is to solve the problems described above, E _H
It is intended to provide a film for Hall effect element having a high mobility, in which only a Hall voltage V _H appears between electrodes, an output voltage V _out that is approximately linear to an applied magnetic field is obtained, and a manufacturing method thereof. is there.

[Means for Solving the Problems]

In order to achieve such an object, the Hall effect element recrystallized film of the present invention has a structure in which a single metal that is a composition material of the compound semiconductor is finely precipitated in a compound semiconductor film, and an applied magnetic field is applied. In contrast, the Hall electrode output voltage has a linear magnetoelectric characteristic.

The method for producing a recrystallized film for a Hall effect element of the present invention comprises uniformly heating a compound semiconductor film to form a melt, and a single metal which is a composition material of the compound semiconductor precipitated in the recrystallized compound semiconductor is The compound semiconductor recrystallized by cooling the melt at a cooling rate large enough to form fine particles, not linear, has a Hall electrode output voltage having a linear magnetoelectric characteristic with respect to an applied magnetic field. Characterize.

The recrystallized film for Hall effect element of the present invention has recrystallized grain boundaries that show random directions in the compound semiconductor film, and the Hall electrode output voltage has a linear magnetic field characteristic with respect to an applied magnetic field. And

The method for producing a recrystallized film for Hall effect device of the present invention is to uniformly heat the compound semiconductor film to form a melt, and the recrystallized grain boundaries generated in the recrystallized compound semiconductor are not parallel to each other but random to each other. The recrystallized compound semiconductor obtained by cooling the melt at a cooling rate high enough to be arranged in any direction is characterized in that the Hall electrode output voltage has a linear magnetoelectric characteristic with respect to the applied magnetic field.

[Action]

As described above, according to the present invention, in the recrystallization method of a compound semiconductor, by relatively increasing the cooling rate from the melt, the precipitated single metal has a property of causing no magnetoresistance, and has a directional magnetoelectric property. It is possible to realize a Hall element having high mobility and having no

〔Example〕

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

First, the formation of the I _n Sb film on a glass substrate method vacuum deposition, sputtering method, a chemical vapor deposition method or the like. I _n Sb film to be formed, it is desirable to control the experimental conditions such that the possible stoichiometric composition. Then, about the I _n Sb film
Coat with 200 Å thick S _i O or In ₂ O ₃ . The reason for coating the S _i O or I _n2 O ₃ is to prevent the re-evaporation and condensation of I _n Sb film when recrystallization melting process. S _i
The O or I _{n 2} O ₃ film formation method is performed by a method such as a vacuum deposition method, a sputtering method, or a film formation of I _{n 2} O ₃ by surface oxidation of I _n Sb. I _n coated in this way
The Sb film in an inert gas atmosphere such as argon gas, or placed in a container in a vacuum, 530 ± 5 ° C. which is the melting point of I _n Sb
Alternatively, heating is performed at a higher temperature. The melting time is the time that the entire I _n Sb film is uniformly melted. I _n Sb
After the film is melted, the film is cooled to room temperature and solidified to obtain a recrystallized film.

At this time, by relatively increasing the cooling rate of I _n Sb film as shown below, high mobility I _n which does not show the direction magnetoelectric properties
An Sb recrystallized film can be obtained.

FIG. 1 shows the relationship between the applied voltage density B and the power voltage V _out appearing between the Hall electrodes E _H of the Hall element made from the film obtained by recrystallizing the I _n Sb deposited film coated with In ₂ O ₃ . It is a characteristic view showing an example of the measurement result of. 1 (A) and (B) show the same I _n
Fig. 1 shows the case of cutting from the Sb raw material film.
(A) shows Hall element characteristics obtained from a film recrystallized at a melting temperature of 534 ° C., a melting time of 10 minutes, and a cooling rate of 2.67 ° C./min. FIG. 1 (B) shows a melting temperature of 534 ° C. Hall element characteristics obtained from a film recrystallized under the conditions of ℃, melting time of 10 minutes, and cooling rate of 4.17 ℃ / min.

As is clear from the comparison of FIGS. 1 (A) and (B), FIG.
In (A), the output voltage V _out is the applied magnetic field (magnetic flux density = B)
, The output voltage V _out shows almost linearity in the direction of the applied magnetic field. It can be seen that, contrary to the fact that many Hall elements made of recrystallized films show directional magnetoelectricity, this shows the linearity desirable for Hall effect elements.

Now, as a measure for evaluating the equilibrium of the output voltage appearing between the Hall electrodes shown in FIG. 9 in the positive magnetic field and the negative magnetic field, the following magnitude δ will be defined with reference to FIG.

In the above equation, V _out (+1 Tesla) represents the output voltage when the magnetic field B is +1 Tesla, and V _out (-1 Tesla) is the magnetic field B of -1 Tesla.
Indicates the output voltage when sla. In order to simplify the discussion, even if the curve is as shown in FIG. 1 (A), the output voltage V _out (+1 Tesla) and V at +1 Tesla and −1 Tesla are
The value of δ is obtained by finding _out (−1Tesla).

Here, if the characteristic expression of the output voltage V _out and the magnetic flux density B passes through the origin and is a straight line, the value of δ becomes zero, and when it deviates from the straight line, that is, it becomes unbalanced with respect to the direction of the magnetic field. δ
The value of becomes large. Therefore, by determining the value of δ, it can be determined whether or not the Hall element is suitable. The smaller the value of δ, the better the linearity becomes, and the smaller the directional magnetoelectric property becomes, which is suitable for the Hall element.

Figure 3 is cooled in recrystallization I _n Sb film, without the molten state by heating to a temperature range of five hundred and thirty to five hundred and forty ° C., the value of δ in the case of changing the cooling rate to solidus temperature thereafter It is the experimental result of the relationship with the speed. As is apparent from FIG. 3, when the cooling rate is relatively small, the value of δ is distributed in a large and small range, whereas when the cooling rate is relatively large, the value of δ is small. You can see that The cause of this is the In _{n of} the elemental metal precipitated during recrystallization by X-ray diffraction.
And Sb. Although the raw material I _n Sb film before recrystallization is approximately stoichiometric composition, showing the X-ray diffraction pattern of recrystallized film recrystallization from raw materials it seems slightly Sb exceeded in Figure 4. In Fig. 4, ΣI (I _n Sb + Sb) is 20 ° <2
θ <90 ° (here, theta is the Bragg angle) represents the sum of the diffraction intensity at each surface of the diffraction intensity and Sb on each side of I _n Sb in, .SIGMA.I (Sb) is likewise 20 ° <2θ <90 Shows the sum of diffraction intensities on each surface of Sb at °. The horizontal axis represents the cooling rate.

Comparing FIG. 3 and FIG. 4, it can be seen that the two characteristic diagrams have a similar relationship. That is, in FIG. 4, when the cooling rate is relatively low, the values of ΣI (Sb) / Σ (I _n Sb + Sb) are distributed in a large and small range, while when the cooling rate is relatively high, ΣI The value of (Sb) / Σ (I _n Sb + Sb) remains low.

Figure 5 was measured by the value and room temperature δ of recrystallized I _n Sb film
It is a characteristic diagram showing the relationship between I _n Sb Hall mobility mu _H film. It can be seen from FIG. 5 that the lower the value of δ, the higher the value of the hole mobility μ _H.

Figure 6 is a state diagram of the I _n Sb alloy. I _n stoichiometry
After melting the Sb film, cooled (in FIG. 6, the state change shown by arrows s), but it is best that making recrystallization film, in fact, slightly Sb excess or I _n excess consisting of I _n Sb film as a recrystallization raw materials. At that time, in the sixth figure, passes through the liquidus BE when the cooling from above 530 ° C. melt in film Sb excess (melt + I _n Sb), and the 500
It solidified through the ℃ solidus CE and I _n Sb crystal and Sb and I _n Sb
Of eutectic crystals (state change indicated by arrow p in the figure). I _n Sb as I _n is in excess of the film is cooled
And pass the liquidus AB from the melt, (melt + I _n Sb), and the passing through the solidus AD of 155 ° C. I _n Sb crystal and I _n and I _n Sb
A eutectic crystal of and is precipitated (state change indicated by arrow q in the figure).

Now, consider a simple metal amount to be deposited on the magnitude of the cooling rate from the results of X-ray diffraction is changed, given an alloy phase diagram shown in FIG. 6, the composition ratio of I _n and Sb component is changed It is hard to think from the "leverage theorem" of the state diagram as long as it is not done.
That is, on the solidus CE And similarly on the solidus line AD Then, their quantity ratio is determined.

Therefore, the recrystallized film thus formed was observed under a microscope. 7th
The figure is a diagram simulating a microscope observation image. FIG. 7 (A) shows the results obtained at a relatively slow cooling rate (4.77 ° C./min). In FIG (A), because the cooling rate is gradual, dendritic (dendrite) grow crystals large, Sb or I _n of the linear single metal is precipitated at the interface of the crystal. In FIG. (B), since the cooling rate is large, the small particulate elemental metal in the recrystallized I _n Sb is precipitated is observed. Further, in FIG. 6C, in the recrystallized film at a relatively high cooling rate, crystal grains may grow in random directions.

When X-ray diffraction is performed, the crystal growth of the single metal in FIG. 7 (A) is large, but in comparison with FIG. 7 (B) and (C), the single metal shows small grains or random directions. Since the crystallinity of the metal between crystal grains is poor, the X-ray diffraction intensity is relatively high in FIG. 7 (A) and relatively low in FIGS. 7 (B) and (C).

When these recrystallized films are processed into Hall elements,
In (A), in order to linear single metal acts as a short-circuit electrode in I _n Sb crystals, as compared to magnetoresistive appears strongly in the FIG. 7 (B) in I _n Sb crystals Although there is a small lump of a single metal, it does not work as a short-circuit electrode, and in Fig. 7 (C), because the crystal grains are randomly arranged, the short-circuit electrode effect does not appear, so the magnetic resistance is almost zero. Does not happen.

From the above description, the Hall element made of the recrystallized film shown in FIG. 7 (A) has a directional magnetoelectric property, and the Hall element made of the recrystallized film shown in FIGS. 7 (B) and (C) has a directional magnetoelectric property. It has no sex. Therefore, the recrystallized film shown in FIGS. 7 (B) and 7 (C) is suitable for processing and use as a Hall element.

The recrystallization method is not only I _n Sb, other compounds semiconductor such as _{AlSb, G a Sb, G a} A s, I n A s, G a P, I n P, G a A s P, G a AlA _s , I
_It can also be applied to _n G _a P, etc.

〔The invention's effect〕

As described above, according to the present invention, in the Hall element obtained from the recrystallized film produced by relatively increasing the cooling rate from the melt of the compound semiconductor, the deposited single metal has a magnetoresistance. It is a property that does not occur, and it is possible to realize a Hall element having high mobility without directional magnetoelectricity.

Furthermore, according to the present invention, it is possible to manufacture a Hall element with low mobility and high mobility without using an expensive bulk single crystal, which greatly contributes to the practical application of the magnetoelectric conversion device.

[Brief description of drawings]

FIG. 1 is an output voltage characteristic diagram of a Hall element formed of a recrystallized film illustrating the effect of the present invention, FIG. 2 is an explanatory diagram for defining the linearity of the output voltage of the Hall element, and FIG. FIG. 4 is a characteristic diagram showing the relationship between the value of δ defined in FIG. 2 and the cooling rate, and FIG. 4 is a characteristic diagram showing the relationship between the X-ray diffraction intensity of the single metal mixed in the recrystallized film and the cooling rate. 5 figures characteristic diagram showing the relationship between the value of mobility and δ of the Hall element, FIG. 6 is a state diagram of the I _n Sb alloy, FIG. 7 (a), (B) and (C), re respectively plan view simulating a microscopic image of crystal films, Figure 8 and Figure 9 is a perspective view showing the structure and the Hall elements example using the same crystal film obtained by a conventional I _n Sb recrystallized film manufacturing method, FIG. 10 is a characteristic diagram showing the relationship between the output voltage component appearing between the output voltage electrodes shown in FIG. 9 and the magnetic flux density.

Claims (4)

[Claims] 1. A compound semiconductor film has a structure in which a single metal, which is a composition material of the compound semiconductor, is finely deposited, and the Hall electrode output voltage has a linear magnetoelectric characteristic with respect to an applied magnetic field. Characterized recrystallized film for Hall effect devices. 2. The compound semiconductor film is uniformly heated to form a melt, and the simple substance metal that is the composition material of the compound semiconductor precipitated in the recrystallized compound semiconductor does not become linear but becomes fine particles. The recrystallized compound semiconductor obtained by cooling the melt at a moderately large cooling rate is characterized in that the Hall electrode output voltage has a linear magnetoelectric characteristic with respect to an applied magnetic field. Manufacturing method. 3. A Hall effect element reproducing device having a recrystallized grain boundary showing a random direction in a compound semiconductor film, wherein the Hall electrode output voltage has a linear magnetic field characteristic with respect to an applied magnetic field. Crystal film. 4. A compound semiconductor film is uniformly heated to form a melt, and the recrystallized grain boundaries generated in the recrystallized compound semiconductor are not parallel to each other but are oriented in random directions. A method for producing a recrystallized film for Hall effect element, wherein the compound semiconductor recrystallized by cooling the melt at a cooling rate has a Hall electrode output voltage having a linear magnetoelectric characteristic with respect to an applied magnetic field. .