JP2001126603A - Micro machine switch and method of manufacturing it - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a micro machine switch with high performance that may be produced in high volume at low cost. SOLUTION: A flexible elongated member is mounted on a substrate by means of a support member arranged near a gap thereon. A contact electrode is arranged opposite to the gap in relation to the flexible elongated member. A lower electrode is arranged opposite to a part of the flexible elongated member. The flexible elongated member has a portion placed between the junction with the support member and the position opposite to the lower electrode that serves as the upper electrode. It also has a portion between the junction of with the support member and the position facing the lower electrode that comprises at least two kinds of materials with different thermal expansion coefficients in the direction of thickness perpendicular to the substrate surface. The contact electrode is arranged with interposition of an insulation member having thickness greater than that of the flexible elongated member arranged in the substrate.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a micromachine switch and a method of manufacturing the same, and more particularly to a micromachine switch capable of turning on / off a wide signal frequency from DC (direct current) to gigahertz or more, and a method of manufacturing the same.

[0002]

2. Description of the Related Art Conventionally, a "fine electromechanical switch" by Yun Jason Yao of Rockwell International Corporation (JP-A-9-17300).
The prior art will be described by taking the invention described in (1) as an example.

FIG. 16 shows a plan view (a) of a micromachine switch disclosed in Japanese Patent Application Laid-Open No. 9-17300 and a sectional view taken along line DD ′ of FIG. As shown in the drawing, an anchor structure 52 made of thermosetting polyimide, a lower electrode 53 made of gold, and a signal line 54 made of gold are provided on a substrate 51 made of gallium arsenide.

A cantilever arm 55 made of a silicon oxide film is provided on the anchor structure 52. The cantilever arm 55 extends to the position of the signal line 54 beyond the lower electrode 53. They are opposed to each other via a spatial gap.

On the upper side of the cantilever arm 55, an upper electrode 56 made of aluminum is connected to the lower electrode 53 by the anchor structure 52.
Are manufactured up to a position opposed to. A contact electrode 57 made of gold is provided below the cantilever arm 55 at a position facing the signal line 54.

When a voltage of 30 V is applied between the upper electrode 56 and the lower electrode 53 in the micromachine switch having such a structure, the upper electrode 56 is attracted toward the substrate (downward by the arrow 58) by the electrostatic force. Works.
Therefore, the cantilever arm 55 is deformed toward the substrate, and the contact electrode 57 contacts both ends of the signal line 54.

In a normal state, as shown in FIG. 16B, a gap is provided between the contact electrode 57 and the signal line 54, so that the two signal lines 54 are separated from each other. Therefore, when no voltage is applied to the lower electrode 53, no current flows through the signal line 54.

However, when a voltage is applied to the lower electrode 53 and the contact electrode 57 is in contact with the signal line 54, the two signal lines 54 are short-circuited and a current can flow between them. Therefore, by applying a voltage to the lower electrode 53, on / off of a current or a signal passing through the signal line 54 can be controlled.

However, in order to reduce the loss of the switch, particularly when this switch is used for signals in the microwave region, the upper electrode 56 and the contact electrode 57 must be electrically insulated sufficiently. is important. That is, if the upper electrode 56 and the contact electrode 57 are electrically short-circuited, a signal (including DC) flowing through the signal line 54 also flows out to the upper electrode 56.

Further, even if the upper electrode 56 and the contact electrode 57 are not short-circuited, in a state where the capacitance is considerably large, an AC signal flowing through the signal line 54 is still applied to the upper electrode 5.
6 and leak to the outside. Thus, the upper electrode 56
When the insulation between the electrode and the contact electrode 57 is not sufficient, signal leakage increases and the characteristics of the switch deteriorate. In the conventional example described above, from such a viewpoint, an insulating material (silicon oxide film) is used as a material for forming the cantilever arm 55.
You are using

[0011]

The above-mentioned conventional micromachine switch has the following problems.
The cantilever arm 55 has a large area in contact with the upper electrode 56 and the anchor structure 52 made of different materials. Further, in order to suppress the driving voltage of the switch, the cantilever arm 55 has a mechanically soft structure and can be moved by a minute voltage.

As described above, in the conventional micromachine switch, since the upper electrode 56, the cantilever arm 55, and the anchor structure 52 are formed of different materials, they have different coefficients of thermal expansion. Warpage tends to occur due to distortion.

For example, when silicon dioxide, aluminum and polyimide are compared with each other, the thermal expansion coefficient of silicon dioxide is very small, about 1/100 times that of the others. For this reason, the metal portion such as the upper electrode 56 expands due to a change in the process temperature and the temperature of the atmosphere after the device is completed, and the cantilever arm 55 is easily warped.

The presence of such a warp is caused by the substrate 51
Whether it is upward or downward, the switch characteristics are adversely affected. If the warp of the cantilever arm 55 is upward, the contact electrode 57 does not contact the signal line 54 even if the lower surface of the cantilever arm 55 contacts the lower electrode 53 when a voltage is applied. May occur. In this case, even if the contact electrode 57 and the signal line 54 come into contact with each other, the pressure at the contact portion is extremely small, and there is a problem that such a light contact increases the contact resistance.

On the other hand, when the warp of the cantilever arm 55 is downward, the contact electrode 57 contacts the signal line 54 by applying a voltage, but the entire contact electrode 57 is planarly connected to the signal line 54. Instead of contact, so-called one-side contact (contact in only a part of the area) is likely to occur. Therefore, also in this case, there is a problem that the contact resistance of the switch increases. In any case, if the cantilever arm 55 is warped, the contact resistance increases, and the switch resistance at the time of ON increases.

In fact, in the conventional example, by performing the process of manufacturing the switch at a low temperature of 250 ° C. or less,
Warpage is suppressed by the process temperature.

Specifically, a silicon dioxide film forming the cantilever arm 55 is manufactured by a plasma CVD (PECVD) process. The advantage of PECVD oxide films is that they can be made at low temperatures, and thus keeping the process temperature low is important in reducing the effects of large differences in the coefficients of thermal expansion of different materials.

On the other hand, the mechanical properties (strain, rigidity, reliability, etc.) and electrical properties (dielectric constant, maximum breakdown voltage, etc.) of the material
However, it is well known that this can be remarkably improved particularly by optimizing the temperature conditions. However, in the above-described conventional example, it is necessary to keep the process temperature low, so that the temperature parameters cannot be used sufficiently for material optimization, and it can be said that there is a large limit in material.

In general, when the thickness of the cantilever arm 55 is increased in order to keep the rigidity of the cantilever constant, there is an advantage that the width of the arm can be reduced. Therefore, there is an advantage that the size of the entire switch can be reduced, and that many switches can be manufactured in a small area.

However, the silicon dioxide cantilever arm 5
5 has a large limitation in the thickness direction of the cantilever arm 55. In principle, the thickness of the silicon dioxide film can be reduced by increasing the time of PECVD.
Although it is possible to increase the thickness even if the thickness is 10 μm or more, if the growth time is long, the processing speed of the apparatus is reduced and the cost is increased. Also, dust tends to be generated inside the apparatus, and it is necessary to frequently perform cleaning. Various problems occur in equipment maintenance.

Further, there is a problem that a large strain is generated inside the thick film and the substrate 51 is destroyed during the deposition. For these reasons, the thickness is practically limited to about 2 μm at present. For this reason, there are severe restrictions on the design dimensions of the switch structure.

Although the reduction of the process temperature as in the conventional example has a certain effect on the suppression of warpage during manufacturing,
It does not play any role in warping due to temperature fluctuations in the use atmosphere. This warpage during use is an inevitable problem in the case where laminated films having different thermal expansion coefficients are used for the arm portions. On the other hand, the switch having the conventional structure has problems in mechanical strength and durability. When the switch is driven, the largest stress occurs at the root of the cantilever arm 55 (the connection portion with the anchor structure 52). Therefore, in order to improve the mechanical strength and durability of the switch, it is necessary to optimize the structure of the root portion. However, in the structure of the conventional example, the cantilever arm 55 and the anchor structure 52 are formed of different materials, and furthermore, both are at right angles. Such a structure is not suitable for relaxing the stress generated at the root.

An object of the present invention is to solve such a problem, and an object of the present invention is to provide an inexpensive and high-performance micromachine switch which can be mass-produced and a method of manufacturing the same.

[0024]

In order to achieve the above object, one embodiment of a micromachine switch according to the present invention includes a first signal line provided on a substrate, and a first signal line provided on the substrate; A micromachine switch for controlling conduction / non-conduction between a first signal line and a second signal line provided with an end at a predetermined gap from an end of the first signal line. A flexible beam member supported on the substrate by a support member provided as above, a contact electrode provided at a position on the substrate side of the beam member at least facing the gap, and A lower electrode provided so as to face a part of the beam member, wherein the beam member has conductivity from a connection portion with the support member to a position facing the lower electrode, thereby forming an upper electrode. Functioning, and at least in a partial region from a connection portion with the support member to a position facing the lower electrode, the substrate with respect to a center plane of the beam member parallel to the substrate surface. It is made of two or more materials arranged so that the thermal expansion coefficient along the thickness direction perpendicular to the surface is symmetric, and the contact electrode is provided on the surface of the beam member on the substrate side. It is provided via an insulating member that is thicker than the insulating member that is provided.

Another embodiment of the micro machine switch according to the present invention includes the following configuration. That is,
Between a first signal line provided on the substrate and a second signal line provided on the substrate and having an end provided at a predetermined gap from an end of the first signal line; A flexible beam member supported on the substrate by a support member provided in close proximity to the gap on the substrate, and the substrate side of the beam member. A contact electrode provided at least at a position facing the gap, and a lower electrode provided on the substrate so as to face a part of the beam member, wherein the beam member is connected to the support member. It functions as an upper electrode by having conductivity from a portion to a position facing the lower electrode, and in at least a partial region from a connection portion with the support member to a position facing the lower electrode. The thermal expansion coefficient along a thickness direction orthogonal to the substrate surface is symmetrical with respect to a center plane of the beam member parallel to the substrate surface, and a region from the upper electrode to the contact electrode is formed. Includes a structure consisting only of an insulating member.

Also, a first signal line provided on the substrate and a second signal line provided on the substrate and having an end provided at a predetermined gap from an end of the first signal line. A micromachine switch for controlling conduction / non-conduction between a signal line and a flexible beam member supported on said substrate by a support member provided on said substrate in proximity to said gap; A contact electrode provided at a position facing the gap at least on the substrate side of the member, and a lower electrode provided on the substrate so as to face a part of the beam member; It functions as an upper electrode by having conductivity from a connection portion with a support member to a position facing the lower electrode, and
At least in a part of a region between the connection portion with the support member and a position facing the lower electrode, a thickness direction perpendicular to the substrate surface with respect to a center plane of the beam member parallel to the substrate surface. Are configured to be symmetrical with each other, and the lower electrode is provided on the substrate between the support member and the gap, and has a thickness of the second electrode. It is made of a conductive material thinner than the thickness of the first and second signal lines.

The angle between the surface of the beam member on the substrate side and the surface of the beam member connected to the support member is an obtuse angle. Further, the support member protrudes to a position higher than a surface of the beam member opposite to the substrate at a connection portion with the beam member. Also,
The angle between the surface of the beam member opposite to the substrate and the surface of the support member protruding higher than the opposite surface is an obtuse angle.

The angle between the surface of the beam member on the substrate side and the side surface of the support member to which the beam member is connected is an obtuse angle.

Further, the beam member has a reinforcing member provided on a surface opposite to a surface on which the contact electrode is provided, facing the contact electrode. Further, the contact electrode includes the first and second contact electrodes.
Is covered with an insulator film that can be connected to the signal line with a capacitor. Further, the support member and at least a part of the beam member have an integral structure made of the same conductive member.

Further, the conductive member is made of a semiconductor material. Further, the beam member is formed of a semiconductor material, and at least a region from a portion where the contact electrode is provided to a portion facing the lower electrode is insulated. Further, the semiconductor material is a single crystal semiconductor. Further, the semiconductor material is an amorphous semiconductor or a polycrystalline semiconductor.

Further, the substrate is a glass substrate or a ceramic substrate. Further, the substrate is a gallium arsenide substrate. Further, the micromachine switch is used for a phased array antenna device. Further, a micromachine switch including a plurality of beam members supporting the same contact electrode and a plurality of support members supporting the beam members.

[0032] In one embodiment of the method of manufacturing a micromachine switch according to the present invention, the first signal line provided on the substrate and the end of the first signal line provided on the substrate have a predetermined length. A second end provided with a gap
Forming a lower electrode on the substrate, a supporting member having a predetermined height, and a supporting member provided on the supporting member. A member composed of a flexible beam member and a contact electrode provided on the beam member is placed on the substrate in a state where the contact electrode faces the gap and is separated from the first and second signal lines. Bonding, the beam member functions as an upper electrode by having conductivity from a connection portion with the support member to a position facing the lower electrode, and at least a connection with the support member. In a part of the region from the portion to the position facing the lower electrode, the coefficient of thermal expansion along the thickness direction perpendicular to the substrate surface is smaller than the center plane of the beam member parallel to the substrate surface. An insulating member made of two or more kinds of materials arranged so as to have a thickness larger than an insulating member when the contact electrode is provided on the surface of the beam member on the substrate side. It is provided through.

Further, other aspects of the method of manufacturing a micromachine switch according to the present invention include the same configuration as that of the above-described micro my switch for each component.

With this configuration, the present invention provides
The thermal expansion coefficient is substantially symmetrical along the thickness direction orthogonal to the substrate surface of the beam member. For this reason, the warpage caused by the strain generated between different materials as in the conventional example is remarkably reduced. Thus, the simplest way to make the coefficient of thermal expansion symmetrical in the thickness direction is to construct the beam member from a single material. In addition, it is of course possible to adopt a vertically symmetric laminated structure.

Here, in order to suppress the warpage of the beam member, in particular, in the vicinity of the portion where the beam member is connected to the support member, more specifically, in the vicinity of the position facing the lower electrode from the connection portion with the support member It is effective to make the coefficient of thermal expansion symmetrical as described above in the region up to. Conversely, in the vicinity of the tip of the beam member, the occurrence of warpage is small even if the thermal expansion coefficient is not symmetrical along the thickness direction. By the way, when a switch manufactured as a trial was measured, a variation in contact resistance caused by one-sided contact and the like was reduced, and a large number of switches having uniform characteristics could be manufactured.

It has also been found that the change in switch operation is extremely small even when the ambient temperature of the switch changes. Further, according to the configuration of the present invention, the mechanical strength, durability and high-speed operation of the switch are significantly improved as compared with the related art. For example, by making the angle between the beam member and the support member an obtuse angle on the surface on the substrate side, it is possible to prevent the root of the beam member from being broken by stress concentration. In addition, by projecting the support member higher than the beam member, the structure near the root of the beam member can be made to be nearly symmetrical in the vertical direction. This makes it possible to make the thermal expansion coefficient distribution in the vicinity of the root of the beam member including the support member symmetrical, which is effective for preventing the warpage of the beam member.

The fact that the support member protrudes upward is also effective for improving the operation speed of the switch. That is, it is possible to obtain the effect that the speed at which the switch returns from the on state (down state) to the off state (up state) is increased. This is because the stress generated at the root of the beam member increases when the support member protrudes above the beam member. Further, when the switch is turned on / off, the operation is abrupt, so that a phenomenon in which the beam member vibrates up and down (called bound chattering) may occur. Therefore, in order to end such bouncing chattering promptly, it is necessary to generate an appropriate stress at the root of the beam member and to absorb the dynamic energy of the beam member to the supporting member. A structure in which the support member protrudes from the beam member is effective.

Further, in such a micromachine switch, the beam member has the most mechanically weak structure. Therefore, it is desirable to have a structure that prevents the beam member from being broken by contact with the substrate or the like when the switch is mounted on the substrate in the manufacturing process. Therefore, by making the supporting member project from the beam member, a contact accident of the beam member can be suppressed, and the risk of breakage of the switch can be reduced.

Also, when the support member is made to protrude beyond the beam member, it is desirable that the angle between the beam member and the support member be obtuse on the surface opposite to the substrate. This is because the root of the beam member can be prevented from being broken by stress concentration. In the case where the angle between the beam member and the support member is an obtuse angle on the substrate surface side or the opposite surface side, the angle is 100 to 100.
It is preferable that the angle be in the range of 170 °, more preferably in the range of 110 ° to 150 °. By doing so, the effect of reducing the stress concentration described above, and
The action of generating an appropriate stress to improve the operation speed,
Can be compatible.

Further, by forming at least a part including the root portion of the support member and the beam member from the same material, it is possible to reduce the distortion between the two members, suppress the concentration of stress at one point, and improve the strength. The durability for use is improved. Here, the maintenance member, the beam member and the upper electrode are:
When using the same material, the manufacturing process can be simplified.

Further, since the high-temperature process can be used, the selection of the material forming the beam member and the like is widened, and various conductors and semiconductors can be used, and the degree of freedom in material selection is increased. In particular, an insulator film manufactured at a high temperature has excellent withstand voltage characteristics and can be said to contribute to the electrical characteristics of a device.

Further, since the degree of freedom in the thickness direction is increased, the width of the arm can be reduced, and the size of the switch can be reduced. The beam member constituting the present invention has conductivity from at least a portion connected to the support member to a position facing the lower electrode, and the conductivity referred to here is a conductor such as a metal. Not limited to In short, it is only necessary to be able to apply a voltage to the position facing the lower electrode through the support member,
Current hardly flows in this part. Therefore, as the material of the beam member up to the position facing the connection portion with the support member, a metal, a semiconductor material, or the like can be widely used. In the case of using a semiconductor material, the presence or absence of impurity addition and the impurity concentration can be varied in a wide range.

Due to the above-described excellent effects, the micromachine switch of the present invention is required to be integrated not only in a simple switch application in which the micromachine switch is used individually but also in an order of tens of thousands on a large-area substrate. To a phased array antenna.

[0044]

Next, an embodiment of the present invention will be described with reference to the drawings. In each of the following embodiments, the structure of the cantilever arm 8 has a structure corresponding to FIG. 10 or FIG. 11 described later. That is, the cantilever arm 8 is provided with two or more types of two or more kinds arranged so that the coefficient of thermal expansion along the thickness direction perpendicular to the substrate surface is symmetric with respect to the center plane of the cantilever arm 8 parallel to the substrate surface. It is made of material.

[First Embodiment] FIG. 1 shows a plan view (a) of the first embodiment of the present invention and a sectional view (b) taken along the line AA ′ of the first embodiment of the present invention. As shown in the figure, in the present embodiment, a switch body 14 made of silicon and a lower electrode 4 made of gold are provided on a glass substrate 1 having a large dielectric constant.
And a signal line 3 made of gold. An earth plate 2 is formed on the back surface of the substrate 1.

The switch body 14 has an integral structure of the supporting member 7, the cantilever arm 8, and the upper electrode 9. From the support member 7, two cantilever arms 8 made of silicon extend substantially horizontally with respect to the substrate surface. The two cantilever arms 8 can reduce the rotational movement of the arm as compared with a single arm in the conventional example, and help prevent a contact of the switch with one side. However, the number of the cantilever arms 8 may be changed according to conditions, and the present invention includes a structure having one and two or more cantilever arms 8.

In the connection portion between the support member 7 and the cantilever arm 8, angles α and β formed on the surface thereof are formed.
Are preferably adjusted so as to satisfy obtuse angles (90 ° <α, β <180 °). By doing so, the strength of the cantilever arm 8 can be increased, and 1M
The switching operation of a high frequency such as Hz or more is enabled.

At the tip of the cantilever arm 8, an upper electrode 9 made of silicon is provided. The upper electrode 9 faces the lower electrode 4 via a spatial gap. The support member 7 is connected to a signal line 3 a formed on the substrate 1, and the signal line 3 a is electrically connected to the upper electrode 9 via the support member 7 and the cantilever arm 8. .

The insulating member 6 made of an insulating film such as a silicon dioxide or silicon nitride film is
From the position facing the lower electrode 4 to the position facing the signal line 3. A contact electrode 5 made of gold is provided at a position below the insulating member 6 facing the signal line 3.

By providing the insulating member 6 in this manner, a short circuit between the contact electrode 5 and the upper electrode 9 and a contact between the upper electrode 9 and the lower electrode 4 during a switching operation can be prevented. However, the insulating member 6 may be at least between the contact electrode 5 and the upper electrode 9. When switching a high-frequency signal, the surface of the contact electrode 5 may be covered with an insulating film as long as the signal line 3 can be capacitively coupled. Conversely, the signal line 3 may be covered with an insulator film.

As described above, since the upper electrode 9 which is thicker than the cantilever arm 8 is provided above the insulating member 6 facing the contact electrode 5, the contact electrode 5 and the insulating member 6 Warpage due to distortion generated during the process can be suppressed. Therefore, the contact electrode 5 can be constantly kept parallel to the substrate 1, and an increase in contact resistance due to one contact can be suppressed.

Here, the operation of the present embodiment will be described. When a voltage of 30 V is applied between the upper electrode 9 and the lower electrode 4 via the signal line 3a, an attractive force acts on the upper electrode 9 toward the substrate (downward) due to the electrostatic force. For this reason, the cantilever arm 8 bends downward and the contact electrode 5 comes into contact with the signal line 3.

The signal line 3 is provided with a gap at a position facing the contact electrode 5 as shown in FIG. Therefore, no current flows through the signal line 3 when no voltage is applied, but current can flow through the signal line 3 when the voltage is applied and the contact electrode 5 is in contact with the signal line 3. As described above, the ON / OFF of the current or the signal passing through the signal line 3 can be controlled by applying the voltage to the lower electrode 4. When a signal of 30 GHz is handled, the conventional H
While the insertion loss of the EMT (High Electron Mobility Transistor) switch was 3 to 4 dB, the switch of the present embodiment obtained a result of 2.5 dB.

As described above, in the present embodiment, the upper electrode 9
Is a conductive support member 7 via a conductive cantilever arm 8.
Since it is electrically connected to the upper electrode 9, it is possible to easily apply a voltage to the upper electrode 9. However, the upper electrode 9 may be in an electrically floating state. In that case, the signal line 3a is unnecessary, and only a voltage needs to be applied to the lower electrode 4 to operate the switch.

Further, the support member 7, the cantilever arm 8, and the upper electrode 9 can be made of a semiconductor in which impurities are partially or wholly diffused. In that case, the current flowing between the upper electrode 9 and the lower electrode 4 during the operation of the switch is:
Since they are extremely small, it is not necessary to precisely control the content of these semiconductor impurities.

Further, as described in the following manufacturing method, it is easy to control the thickness of the cantilever arm 8 to be thinner than other components. By controlling the thickness of each element in this manner, a soft cantilever arm 8 can be manufactured in a component having high rigidity. Therefore, in the case of an element having high rigidity, the deformation at the time of applying a voltage is performed horizontally with respect to the substrate 1, and most of the deformation is performed by the thin cantilever arm 8. This helps to keep the switch hitting low.

However, the present invention includes a case where the thickness of the upper electrode 9 is the same as that of the cantilever arm 8. Such a structure has an advantage that the manufacturing method is simplified.

Table 1 shows typical dimensions of this embodiment.

[0059]

[Table 1] Here, the width is the length in the vertical direction with respect to the plan view of FIG. 1A, the length is the horizontal length with respect to the plan view of FIG.
The thickness indicates the length in the vertical direction with respect to the cross-sectional view of FIG.

However, these dimensions are to be designed according to individual applications, and are not limited to the above numerical values. In the present invention, a wide range of design is possible due to the increased design flexibility.

Here, the manufacturing process of the micromachine switch according to FIG. 1 will be described with reference to the drawings. Figures 2 and 3
FIG. 2 is a cross-sectional view showing a manufacturing process of the micromachine switch according to FIG. The manufacturing process will be described sequentially.

First, as shown in FIG. 2A, a pattern 1 made of a silicon dioxide film is formed on a substrate 11 made of silicon.
2 to form tetramethylammonium hydroxide (TMA
The substrate 11 is etched by about 6 μm using an etching solution such as H). Here, as the substrate 11, (100)
When silicon having a main surface as the main surface is used, the (111) plane has a trapezoidal shape with the side surfaces exposed after etching due to the plane orientation dependence of the etching rate.

Next, as shown in FIG. 2B, a new pattern 13 is formed on the substrate 1 and boron is diffused into a region without the mask using the pattern 13 as a mask. For example, thermal diffusion is performed at 1150 ° C. for about 10 hours. At this time, high-concentration boron is diffused to a depth of about 10 μm. As a result, the support member 7 and the upper electrode 9 are manufactured.

Next, as shown in FIG. 2C, after removing the pattern 13 in the area corresponding to the cantilever arm 8,
Using the remaining pattern 13 as a mask, boron is diffused into a region without the mask. As a result, a switch body 14 including the support member 7, the cantilever arm 8, and the upper electrode 9 is completed. In this case, to diffuse boron shallowly,
For example, thermal diffusion is performed at 1150 ° C. for about 2 hours. At this time, high concentration boron is diffused to a depth of about 2 μm.

Then, as shown in FIG. 2D, the upper electrode 9 has a silicon dioxide of 1 μm and a nitride film of 0.05 μm.
The insulating member 6 made of is manufactured.

Next, as shown in FIG. 3E, a contact electrode 5 is formed on the insulating member 6 by using gold plating.

Then, as shown in FIG. 3 (f), the substrate 11 thus manufactured was placed on the lower electrode 4 made of gold.
And the signal lines 3 and 3a made of gold. This substrate 1 is prepared in advance in a step separate from the above-described silicon process. After that, the support member 7 is bonded onto the substrate 1. At this time, electrostatic bonding technology can be used for bonding silicon and glass.

Finally, as shown in FIG.
1 is introduced into an etching solution having a high boron concentration selectivity such as ethylenediamine pyrocatechol, and a portion where boron is not diffused is dissolved. As a result, a micromachine switch can be manufactured on the substrate 1.

If the substrate 1 is made of ceramic, gallium arsenide, or the like, the support member 7 can be bonded to these substrates using an adhesive. Alternatively, apply 2 to 5 μm of glass on the surface of these substrates.
If m is sputtered, it is also possible to use electrostatic bonding technology.

As described above, in this embodiment, the switch main body 14 including the cantilever arm 8 and the like is manufactured by etching the single crystal silicon substrate. As described above, this embodiment has an advantage that a structure with the highest mechanical characteristics can be manufactured by using a single crystal as a material.

Further, since the cantilever arm 8 is made of only a single crystal, warpage due to the thermal expansion coefficient does not occur as compared with a structure in which a plurality of materials are bonded as in the conventional example. That is, the change in the coefficient of thermal expansion of the cantilever arm 8 along the direction orthogonal to the surface of the substrate 1 is symmetrical between the substrate surface side and the opposite surface side.
Warpage is suppressed.

On the other hand, besides the method described here, the substrate 1
It is also possible to fabricate a switch having the structure of the present invention by depositing various thin films thereon and using selective etching. For example, the switch body 14 is not made of single-crystal silicon but is made of amorphous silicon, polysilicon, or a high-resistance semiconductor material (such as GaAs or iron-doped InP).
It may be produced by using. Further, the switch body 14 may be made of a metal such as gold or aluminum instead of a semiconductor.

Next, another embodiment of the present invention will be described with reference to the drawings. [Second Embodiment] FIG. 4 shows a plan view (a) and a sectional view taken along the line BB 'of FIG. 4 of a second embodiment of the present invention. As shown in FIG. 1, in the present embodiment, a support member 7 made of silicon, a lower electrode 4 made of gold, and a signal line 3 made of gold are formed on a glass substrate 1 having a large dielectric constant.
Is provided. A ground plate 2 is provided on the back surface of the substrate 1.
Are formed.

The switch body 14 has an integral structure of the support member 7, the cantilever arm 8, and the upper electrode 9. From the support member 7, two cantilever arms 8 made of silicon extend substantially horizontally with respect to the substrate surface. The two cantilever arms 8 can reduce the rotational movement of the arm as compared with a single arm in the conventional example, and help prevent a contact of the switch with one side. However, the number of the cantilever arms 8 may be changed according to conditions, and the present invention includes a structure having one and two or more cantilever arms 8.

At the connection between the support member 7 and the cantilever arm 8, the angles α, β
Are preferably adjusted so as to satisfy obtuse angles (90 ° <α, β <180 °). By doing so, the strength of the cantilever arm 8 can be increased, and 1M
The switching operation of a high frequency such as Hz or more is enabled.

At the tip of the cantilever arm 8, an upper electrode 9 made of silicon is provided. The upper electrode 9 faces the lower electrode 4 via a spatial gap. The support member 7 is connected to a signal line 3 a formed on the substrate 1, and the signal line 3 a is electrically connected to the upper electrode 9 via the support member 7 and the cantilever arm 8. .

The insulating member 6 made of an insulating film such as a silicon dioxide or silicon nitride film is
And extends to a position facing the signal line 3. A contact electrode 5 made of gold is provided at a position below the insulating member 6 facing the signal line 3. When switching a high-frequency signal, the surface of the contact electrode 5 may be covered with an insulating film as long as it can be capacitively coupled to the signal line 3. Conversely, the signal line 3 may be covered with an insulator film.

Above the insulating member 6 facing the contact electrode 5, a reinforcing member 10 made of silicon is provided. This is provided in order to suppress warpage due to distortion generated between the contact electrode 5 and the insulating member 6. Thus, by providing the reinforcing member 10,
The contact electrode 5 can always keep a state parallel to the substrate 1 and can suppress an increase in contact resistance due to a contact. The reinforcing member 10 is not always necessary depending on the material and the thickness of the insulating member 6, and a structure without such a member is also included in the present invention.

Here, the operation of the present embodiment will be described. When a voltage of 30 V is applied between the upper electrode 9 and the lower electrode 4, an attractive force acts on the upper electrode 9 toward the substrate (downward) due to the electrostatic force. For this reason, the cantilever arm 8 bends downward and the contact electrode 5 comes into contact with the signal line 3.

The signal line 3 has a gap at a position facing the contact electrode 5 as shown in FIG. Therefore, no current flows through the signal line 3 when no voltage is applied, but current can flow through the signal line 3 when the voltage is applied and the contact electrode 5 is in contact with the signal line 3. As described above, the ON / OFF of the current or the signal passing through the signal line 3 can be controlled by applying the voltage to the lower electrode 4. When a signal of 30 GHz is handled, the conventional H
While the insertion loss of an EMT (High Electron Mobility Transistor) switch was 3 to 4 dB, the switch of the present embodiment obtained a result of 0.2 dB.

In the present embodiment, since the upper electrode 9 is electrically connected to the conductive support member 7 via the conductive cantilever arm 8, the voltage can be easily applied to the upper electrode 9. be able to. However, the upper electrode 9 may be in an electrically floating state. In this case, the signal line 3a is unnecessary, and the lower electrode 4 is required to operate the switch.
It is only necessary to apply a voltage to.

The supporting member 7, the cantilever arm 8, the upper electrode 9, and the reinforcing member 10 can be made of a semiconductor in which impurities are partially or entirely diffused. In this case, since the current flowing between the upper electrode 9 and the lower electrode 4 when the switch operates is extremely small, it is not necessary to precisely control the impurity content of these semiconductors.

Further, as described in the following manufacturing method, it is easy to control the thickness of the cantilever arm 8 to be thinner than other components. By controlling the thickness of each element in this manner, a soft cantilever arm 8 can be manufactured in a component having high rigidity. In the case of an element having high rigidity, the deformation at the time of applying a voltage is performed horizontally with respect to the substrate 1, and most of the deformation is performed by the thin cantilever arm 8. This helps to keep the switch hitting low.

However, the present invention includes a case where the thickness of the upper electrode 9 and the reinforcing member 10 is the same as that of the cantilever arm 8. Such a structure has an advantage that the manufacturing method is simplified.

Table 2 shows typical dimensions of the present embodiment.

[0086]

[Table 2] Here, the width is the length in the vertical direction with respect to the plan view of FIG. 4A, and the length is the horizontal length with respect to the plan view of FIG.
The thickness indicates the length in the vertical direction with respect to the cross-sectional view of FIG.

However, these dimensions are to be designed according to individual applications, and are not limited to the above numerical values. In the present invention, a wide range of design is possible due to the increased design flexibility.

Here, the manufacturing process of the micromachine switch according to FIG. 4 will be described with reference to the drawings. Figures 5 and 6
FIG. 5 is a sectional view showing a manufacturing step of the micromachine switch according to FIG. 4. The manufacturing process will be described sequentially.

First, as shown in FIG. 5A, a pattern 1 made of a silicon dioxide film is formed on a substrate 11 made of silicon.
2 to form tetramethylammonium hydroxide (TMA
The substrate 11 is etched by about 6 μm using an etching solution such as H). Here, as the substrate 11, (100)
When silicon having a main surface as the main surface is used, the (111) plane has a trapezoidal shape with the side surfaces exposed after etching due to the plane orientation dependence of the etching rate.

Next, as shown in FIG. 5 (b), a new pattern 13 is formed on the substrate 1, boron is diffused into a region without the mask by using the pattern 13 as a mask, and then deep diffusion of boron is performed. For example, thermal diffusion is performed at 1150 ° C. for about 10 hours. At this time, high-concentration boron is diffused to a depth of about 10 μm. As a result, the support member 7, the upper electrode 9, and the reinforcing member 10 are manufactured.

Next, as shown in FIG. 5C, the pattern 13 in the region corresponding to the cantilever arm is removed, and then the remaining pattern 13 is used as a mask to diffuse boron into the region without the mask. As a result, a switch body 14 including the support member 7, the cantilever arm 8, and the upper electrode 9 is completed. In this case, in order to perform shallow diffusion of boron, thermal diffusion is performed at, for example, 1150 ° C. for about 2 hours. At this time, high concentration boron is diffused to a depth of about 2 μm.

Next, as shown in FIG. 5D, from the upper electrode 9 to the reinforcing member 10, silicon dioxide 1 μm
Then, an insulating member 6 made of a nitride film having a thickness of 0.05 μm is manufactured.

Next, as shown in FIG. 6E, the contact electrode 5 is formed on the insulating member 6 facing the reinforcing member 10 by using gold plating.

Next, as shown in FIG. 6 (f), the substrate 11 thus manufactured was placed on the lower electrode 4 made of gold.
And the signal lines 3 and 3a made of gold. This substrate 1 is prepared in advance in a step separate from the above-described silicon process. After that, the support member 7 is bonded onto the substrate 1. At this time, electrostatic bonding technology can be used for bonding silicon and glass.

Finally, as shown in FIG.
1 is introduced into an etching solution having a high boron concentration selectivity such as ethylenediamine pyrocatechol, and a portion where boron is not diffused is dissolved. As a result, a micromachine switch can be manufactured on the substrate 1.

If the substrate 1 is made of ceramic, gallium arsenide, or the like, the support member 7 can be bonded to these substrates using an adhesive. Alternatively, apply 2 to 5 μm of glass on the surface of these substrates.
If about m is sputtered, it is possible to use electrostatic bonding technology.

As described above, in this embodiment, the switch body 14 including the cantilever arm 7 and the like is manufactured by etching the single crystal silicon substrate. As described above, this embodiment has an advantage that a structure with the highest mechanical characteristics can be manufactured by using a single crystal as a material.

Further, since the cantilever arm 8 is made of only a single crystal, warpage due to a coefficient of thermal expansion does not occur as compared with a structure in which a plurality of materials are bonded as in the conventional example. That is, the change in the coefficient of thermal expansion of the cantilever arm 8 along the direction orthogonal to the surface of the substrate 1 is symmetrical between the substrate surface side and the opposite surface side.
Warpage is suppressed.

On the other hand, besides the method described here, the substrate 1
It is also possible to fabricate a switch having the structure of the present invention by depositing various thin films thereon and using selective etching. For example, the switch body 14 and the reinforcing member 10 may be formed using amorphous silicon, polysilicon, or a high-resistance semiconductor material (such as GaAs or iron-doped InP) instead of single-crystal silicon. Further, the switch body 14 and the reinforcing member 10 may be manufactured using a metal such as gold or aluminum instead of a semiconductor.

[Third Embodiment] FIG. 7 shows a plan view (a) and a sectional view (b) of a third embodiment of the present invention. As shown in the figure, the components having the same reference numerals as those in FIG.
Indicates that the components are the same or equivalent.

The present embodiment differs from the second embodiment in that the insulating member 6b extends from the end surface of the upper electrode 9. The insulating member 6b can be formed by an insulating thin film such as an oxide film or a nitride film, but can be formed by using the same semiconductor material as the upper electrode 9. In this case, the insulating member 6 is made of, for example, a high-resistance semiconductor material (GaAs, InP doped with iron, or the like).
b, cantilever arm 8 and upper electrode 9 excluding b
A method of lowering the resistance by diffusing impurities only into the impurity, a method of implanting ions such as oxygen into the region of the insulating member 6b to increase the resistance, or the like can be used. In the present embodiment, the reinforcing member 10 is provided at a position facing the contact electrode 5, but a structure without such a member is also included in the present invention.

The reinforcing member 10 may have either low resistance or high resistance. In the present embodiment, an insulating member 6a is provided below the upper electrode 9 separately from the insulating member 6b. This is to prevent a short circuit from occurring when the voltage is applied between the upper electrode 9 and the lower electrode 4 due to contact with each other. This insulating member 6a
Is preferably thinner than the contact electrode 5.

The insulating member 6a may be provided on the lower surface of the upper electrode 9 as shown in FIG.
May be provided on the upper surface. Alternatively, it may be provided on both the lower surface of the upper electrode 9 and the upper surface of the lower electrode 4. Further, in the present embodiment, the insulating member 6b is positioned above the substrate 1 as compared with the first embodiment, so that the gap between the contact electrode 5 and the signal line 3 is reduced. Be able to get large. For this reason, the off-state capacitance is reduced, and the off-state leakage current can be reduced.

In the above embodiment, a glass substrate has been described as a specific example of the substrate 1. Glass substrates are cheaper than gallium arsenide substrates and are promising materials for applications such as phased array antennas that require integration of a large number of switches. However, the structure of the present invention is not limited to this, and is also effective for gallium arsenide, silicon, ceramics, printed boards, and the like.

The present invention also includes a method of forming a hole in the upper electrode 9 to reduce the squeezing effect due to air existing between the upper electrode 9 and the lower electrode 4. In the present invention, it is easy to reinforce the strength of the insulating member 6b by the upper electrode 9 and the reinforcing member 10.
For this reason, even if a plurality of holes are provided inside, the rigidity of the entire movable portion can be kept sufficiently large. Further, holes are formed in the insulating member 6b, the contact electrode 5, and the reinforcing member 10 so that the air can be easily passed through, so that the squeeze effect can be significantly suppressed.

[Fourth Embodiment] FIG. 8 is a plan view showing a fourth embodiment of the present invention. In the figure, the same reference numerals in FIG. 1 indicate the same or equivalent components. As shown in FIG. 8, in the present embodiment, the lower electrode 4
Are provided in the gaps of the signal lines 3. Of course, the lower electrode 4 is provided at a position lower than the end of the signal line 3, and the cantilever arm 8 may bend downward and the contact electrode 5 may come into contact with the end of the signal line 3. Also, the contact electrode 5 does not come into contact with the lower electrode 4.

As described above, by providing the lower electrode 4 even slightly ahead of the arm, the arm can be operated with a slight electrostatic force, and the voltage value applied to the lower electrode 4 can be reduced. it can. Of course, when a high-frequency signal is handled in such a configuration, it can be said that a signal flowing through the signal line 3 easily leaks to the lower electrode 4. Therefore, in such a configuration, it is preferable to handle only DC or low frequency signals.

[Fifth Embodiment] FIG. 9 is a sectional view showing a fifth embodiment of the present invention. In the figure, the same reference numerals in FIG. 1 indicate the same or equivalent components. As shown in FIG. 9, in the present embodiment, two support members 7 are arranged on the substrate 1 with the signal line 3 interposed therebetween. Therefore, the upper electrode 9 is connected to the cantilever arms 8 extending from the support members 7 and supported on both sides. Further, in order to generate a sufficient electrostatic force, the lower electrodes 4 are provided at two places under the upper electrode 9 with the signal line 3 interposed therebetween.

As described above, a configuration in which the upper electrode 9 is supported using the plurality of support members 7 is also included in the present invention. Also,
The number of support members 7 may be further increased to two or more, and such a structure is also included in the present invention.

[Sixth Embodiment] FIG. 10 is a sectional view showing a sixth embodiment of the present invention. In the figure,
1 indicate the same or equivalent components. As shown in FIG. 10, in the present embodiment, the surface of the switch body 14 is oxidized to form the cantilever arm 8 into a silicon layer 8a and a silicon oxide layer 8b sandwiching the silicon layer 8a from both sides. is there. in this way,
If the silicon oxide layers 8b on both sides are made equal in thickness,
Since the thermal expansion coefficients of the substrate 1 and the opposite side are symmetric,
Even if the high-temperature processing is performed, the warpage of the cantilever arm 8 is suppressed.

[Seventh Embodiment] FIG. 11 is a sectional view showing a seventh embodiment of the present invention. In the figure,
The same reference numerals in FIG. 10 indicate the same or equivalent components. As shown in FIG. 11, the present embodiment has a superlattice structure in which cantilever arms 8 are alternately stacked with thin films made of two or more materials. As in the sixth embodiment, also in the present embodiment, since the thermal expansion coefficient on the substrate 1 side and the thermal expansion coefficient on the opposite side can be made symmetric, the cantilever arm 8 warps due to a temperature change. Can be suppressed.

[Eighth Embodiment] An example in which the micromachine switch according to the first to seventh embodiments is applied to a phased array antenna will be described. As described below, the above-described micromachine switch can be widely applied to DC to high-frequency signals, and is particularly effective when applied to a phased array antenna device.

FIG. 12 is a block diagram showing a phased array antenna device disclosed in Japanese Patent Application No. 10-176367. As shown in the figure, the phased array antenna device has M antennas (M is a natural number of 2 or more).
3 and the antenna 23 is connected to the phase shift circuit 24. The phase shift circuit 24 includes a data distribution circuit 24a, M data latch circuits 24b connected to the data distribution circuit 24a, and a phase shifter 24c connected to the data latch circuit 24b.

Therefore, each antenna 23 is connected to an N-bit (N is a natural number) phase shifter 24 c, and each phase shifter 24 c is connected to the feeder 21 via the distributor / combiner 22.

The data distribution circuit 24a is connected to the control device 20. Note that the data distribution circuit 24a and the data latch circuit 24b are realized by a thin film transistor circuit (TFT circuit) on a substrate.

The phase shifter 24c has the above-described micromachine switch for each bit, and each data latch circuit 24b is connected to the micromachine switch of each phase shifter 24c. As described above, in the phased array antenna device shown in the figure, the driving circuit of the phase shifter, which has conventionally been an external IC, is constituted by the TFT circuit, and the phase shifter 24c
Etc. are formed in the same layer.

Next, the operation of the phased array antenna device shown in FIG. 12 will be described. Control device 20
Calculates a phase shift amount optimal for directing a radiation beam in a desired direction with N-bit accuracy based on a preset position of the antenna 23 and a frequency to be used, and uses the result as a control signal. Output to the data distribution circuit 24a. The data distribution circuit 24a distributes a control signal to each data latch circuit 24b.

The radiation direction of the radio wave from the antenna 23 is
All antennas 23 can be switched simultaneously. At this time, each data latch circuit 24b rewrites the held data into a control signal as input data in synchronization with a timing signal for switching the beam direction, and requires a phase shifter 24c based on the held data (control signal). Drive voltage is simultaneously applied to the micromachine switch of the bit to be set.

When a drive voltage is applied to a micromachine switch, the micromachine switch closes a circuit and turns on a bit including the micromachine switch. The phase shift amount of the phase shifter 24c is set depending on which bit of the phase shifter 24c is turned on.

Each phase shifter 24c changes the phase of the high-frequency signal by the phase shift amount set in this way,
3 is fed. Each of the antennas 23 emits radiation having a phase corresponding to the feeding phase, and the radiation forms an equiphase plane, thereby forming a radiation beam in a direction perpendicular to the equiphase plane.

Next, a detailed structure of the phased array antenna device according to FIG. 12 will be described. FIG. 13 is an exploded perspective view showing the phased array antenna device.
As shown in the figure, the overall configuration is a multilayer structure. That is, the distribution / combination layer L1, the dielectric layer L2, the feeding slot layer L3, the dielectric layer L4, a layer (hereinafter, referred to as a phase shift circuit layer) L5 including a radiating element, a phase shifter, and a TFT circuit. And the dielectric layer L6 and the parasitic element layer L7 are adhered to each other in close contact.

Each layer is multi-layered using photolithography and etching technology, bonding technology and the like. For example, the parasitic element layer L7 and the phase shift circuit layer L5
Is for the metal film formed on each surface of the dielectric layer L6.
It is formed by performing photolithography and etching techniques. The power supply slot layer L3 is formed by applying photolithography and etching techniques to a metal film formed on one surface of the dielectric layer L4.

A plurality of parasitic elements 32 are formed in the parasitic element layer L7. This parasitic element 32
The dielectric layer L6 is used to extend the band of the antenna.
Through the radiating element of the phase shift circuit layer L5. Further, a dielectric having a relative dielectric constant of about 2 to 10 is used for the dielectric layer L6. For example, if glass is used, the manufacturing cost can be reduced, and it is desirable to use glass for at least one of the dielectric layers. If the problem of the manufacturing cost is ignored, a dielectric such as alumina having a high relative dielectric constant or a foam material having a low relative dielectric constant may be used for the dielectric layer L6.

Next, in the phase shift circuit layer L5, a part of the antenna 23 shown in FIG. 12, a phase shift circuit 24, a strip line for feeding power to the antenna 23, and the like are formed.

Next, the dielectric layer L4 is formed of a dielectric having a relative dielectric constant of about 3 to 12, such as alumina. Next, the power supply slot layer L3 is formed of a conductive metal, and serves as a power supply coupling means.
A plurality of 0s are formed. The power supply slot layer 30
Is connected to the phase shift circuit layer L5 through a through hole appropriately provided in the dielectric layer L4, and functions as a ground for the phase shift circuit layer L5.

Next, in the distribution / combination layer L1, a plurality of distribution / combination units 22 are formed. The distributor / synthesizer 22 is electromagnetically coupled to the phase shift circuit layer L5 via a power supply slot 30 provided in the power supply slot layer L3. One distributor / combiner 22 and one feed slot 30 constitute one feed unit, and the units are arranged in a matrix. However, those not arranged in a matrix are also included in the present invention.

The radiating elements 32 may be arranged in a matrix or simply arranged two-dimensionally. Alternatively, they may be arranged in one direction. In FIG. 13, the distributor / synthesizer 22 and the phase-shift circuit layer L5 are electromagnetically coupled via the power supply slot layer L3. When they are connected by another power supply coupling means, they may be formed on the same surface.

Next, the phase shift circuit layer L5 shown in FIG. 13 will be described in detail. FIG. 14 shows one of the phase shift circuit layers L5.
It is a top view showing a unit. As shown in the figure, a radiating element 41 and a phase shifter group 4 are provided on a dielectric layer L6 such as a glass substrate.
0 and a data latch circuit 46 are formed. However, the data latch circuit 46 is provided for each bit of the phase shifters 40a to 40d.

The strip line 42 is provided from the radiating element 41 via the phase shifter group 40 to a position corresponding to the power supply slot 30 shown in FIG. And as the radiating element 41, for example, a patch antenna,
A printed dipole, a slot antenna, an aperture element, and the like are used. As the strip line 42, a distributed constant line such as a microstrip line, a triplate line, a coplanar line, and a slot line is used.

The phase shifter group 40 shown in FIG. 14 constitutes a 4-bit phase shifter as a whole, that is, is constituted by four phase shifters 40a, 40b, 40c and 40d. Each of the phase shifters 40a to 40d can change the power supply phase by 22.5 °, 45 °, 90 °, and 180 °, respectively, and includes a strip line and a micromachine switch.

Here, each of the phase shifters 40a to 40c includes two strip lines 44 connected between the strip line 42 and the ground 43, and a micromachine switch 45 connected in the middle of the strip line 44. Have been. These phase shifters constitute a loaded line type phase shifter.

On the other hand, in the phase shifter 40d, the micromachine switch 45 connected in the middle of the strip line 42
a, a U-shaped strip line 44a, and a micromachine switch 45a connected between the strip line 44a and the ground 43. This phase shifter constitutes a switched line type phase shifter.

In general, when the amount of phase shift is small, the characteristics of the loaded line type are better, and when the amount of phase shift is large, the characteristics of the switched line type are better.
Therefore, the loaded line type is used as the 22.5 °, 45 °, and 90 ° phase shifters, and the switched line type is used as the 180 ° phase shifter. Of course, the phase shifter 40
It is also possible to use a switched line type for a to 40c.

The two micromachine switches (45 or 45a) included in each of the phase shifters 40a to 40d are connected to a data latch circuit 46 disposed in the vicinity thereof, and are driven by a drive voltage output from the data latch circuit 46. Works at the same time. As described above, the power supply phase of the high-frequency signal flowing through the strip line 42 is changed by the operation of the phase shifter group 40.

Note that, instead of arranging the data latch circuit 46 near each micromachine switch, a plurality of data latch circuits are arranged at one place, and wiring is extended therefrom to drive each micromachine switch. You may. Further, one data latch circuit may be connected to a plurality of different units of micromachine switches.

FIG. 15 is an enlarged plan view of the periphery of the micromachine switch 45 used in the loaded line type phase shifter. As shown in the figure, the two micromachine switches 45 are arranged symmetrically with respect to the two strip lines 44. These micromachine switches 45 are connected to one data latch circuit (not shown), and a driving voltage (external voltage) is simultaneously supplied from the data latch circuit. Of course, as the micromachine switch 45, those described in the first to seventh embodiments can be used.

[0137]

As described above, according to the present invention, the change in the thermal expansion coefficient on the substrate surface side of the beam member having a small mechanical rigidity and the change in the thermal expansion coefficient on the opposite surface side are symmetrical to each other. For this reason, the warpage caused by the strain generated between different materials as in the conventional example is remarkably reduced.
By the way, when a switch manufactured as a trial was measured, a variation in contact resistance caused by one-sided contact and the like was reduced, and a large number of switches having uniform characteristics could be manufactured.

It was also found that the change in switch operation was extremely small even when the ambient temperature of the switch changed.

Further, by manufacturing the support member, the beam member, and the upper electrode with the same material, the manufacturing process can be simplified.

Further, since the high-temperature process can be used, the selection of the material constituting the beam member and the like is widened, various conductors and semiconductors can be used, and the degree of freedom in selecting the material is increased. In particular, an insulator film manufactured at a high temperature has excellent withstand voltage characteristics and can be said to contribute to the electrical characteristics of a device.

Further, since the degree of freedom in the thickness direction is increased, the width of the arm can be reduced, and the size of the switch can be reduced.

Due to the excellent effects described above, the micromachine switch of the present invention is required to be integrated not only in a simple switch application which is used individually but in an order of tens of thousands on a large-area substrate. To a phased array antenna.

[Brief description of the drawings]

FIG. 1A is a plan view showing a first embodiment of the present invention, and FIG. 1B is a sectional view taken along line AA ′ of FIG.

FIG. 2 is a sectional view showing a manufacturing process of the micromachine switch according to FIG. 1;

FIG. 3 is a cross-sectional view showing a manufacturing step continued from FIG. 2;

FIG. 4A is a plan view showing a second embodiment of the present invention, and FIG. 4B is a sectional view taken along line BB ′ of FIG.

FIG. 5 is a sectional view showing a manufacturing step of the micromachine switch according to FIG. 4;

FIG. 6 is a cross-sectional view showing a manufacturing step continued from FIG. 5;

FIG. 7A is a plan view showing a third embodiment of the present invention, and FIG. 7B is a sectional view taken along line CC ′ of FIG.

FIG. 8 is a plan view showing a fourth embodiment of the present invention.

FIG. 9 is a sectional view showing a fifth embodiment of the present invention.

FIG. 10 is a sectional view showing a sixth embodiment of the present invention.

FIG. 11 is a sectional view showing a seventh embodiment of the present invention.

FIG. 12 is a block diagram showing a phased array antenna device (eighth embodiment of the present invention).

13 is an exploded perspective view showing a detailed configuration of the phased array antenna device according to FIG.

FIG. 14 is a plan view showing the phase shift circuit according to FIG.

FIG. 15 is a plan view showing the periphery of the micromachine switch according to FIG. 14;

FIG. 16 (a) is a plan view showing a conventional example, and FIG.
It is a sectional view taken on the line D '(b).

DESCRIPTION OF SYMBOLS 1 ... substrate, 2 ... ground plate, 3, 3a ... signal line, 4 ... lower electrode, 5 ... contact electrode, 6, 6b ... insulating member, 6a ... insulator film, 7 ... support member, 8: cantilever arm, 8a: silicon layer, 8b: silicon oxide layer, 9: upper electrode, 10 ...
Reinforcing member, 11 ... substrate, 12, 13 ... pattern, 14 ... switch body, 20 ... control device, 21 ... power supply, 22 ...
Distributor / combiner, 23 ... antenna, 24 ... phase shift circuit, 24a
... data distribution circuit, 24b ... data latch circuit, 24c
... Phase shifter, 30 ... Power supply slot, 31 ... Phase shift circuit, 3
2 ... parasitic element, 40 ... phase shifter group, 40a, 40b, 4
0c, 40d: phase shifter, 41: radiating element, 42: strip line, 43: ground, 44, 44a: strip line, 45, 45a: micro machine switch, 46:
Data latch circuit, L1... Distribution synthesizing layer, L2, L4, L
6: dielectric layer, L3: feeding slot layer, L5: phase shift circuit layer, L7: parasitic element layer.

────────────────────────────────────────────────── ───

[Procedure amendment]

[Submission date] January 22, 2001 (2001.1.2)
2)

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] Claims

[Correction method] Change

[Correction contents]

[Claims]

[Procedure amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0024

[Correction method] Change

[Correction contents]

[0024]

In order to achieve such an object, a micromachine switch according to the present invention comprises:
A first signal line provided on the board, and a first signal line provided on the substrate.
And a predetermined gap from the end of the first signal line.
Conduction / non-conduction with a second signal line having an end
A micromachine switch for controlling communication,
Having conductivity provided on the plate in close proximity to the gap
A support member, and the gap and the support portion on the substrate.
A lower electrode provided between the support member and the support member;
Conductive and flexible provided parallel to the substrate
A cantilever arm and the lower electrode
Supported in response to a voltage applied to the lower electrode.
And an upper electrode that exerts an attractive force on the lower electrode side.
An insulating member provided in parallel with the substrate,
The upper part is supported above the gap by an edge member.
The first and second signals are responsive to the attraction to an electrode.
And the first and second signal lines by contacting the
A contact electrode that conducts between the cantilever arms;
As symmetric along the thickness direction orthogonal to the substrate.
The one having the following thermal expansion coefficient is used.

[Procedure amendment 3]

[Document name to be amended] Statement

[Correction target item name] 0025

[Correction method] Change

[Correction contents]

[0025] Also, provided below the insulating member.
Provided above the insulating member, facing the contact electrode
And a reinforcing member provided.

[Procedure amendment 4]

[Document name to be amended] Statement

[Correction target item name] 0026

[Correction method] Change

[Correction contents]

[0026] The insulating member may be provided at one end.
It is connected to the lower surface of the upper electrode. Also, the insulation
One end of which is connected to the end surface of the upper electrode.
It is. Further, the lower electrode or the lower electrode of the upper electrode may be used.
The top of the pole prevents short circuits between its upper and lower electrodes.
This is provided with a short-circuit prevention insulating member that stops. Ma
In addition, the thickness of the short-circuit prevention insulating member
It is thinner than that.

[Procedure amendment 5]

[Document name to be amended] Statement

[Correction target item name] 0027

[Correction method] Change

[Correction contents]

Further , the lower electrode is provided on the substrate,
Position lower than the first and second signal lines in the gap
And the upper electrode is provided by the cantilever arm.
It is provided to extend so as to face the lower electrode.
Further, it is provided above the upper electrode so as to face the contact electrode.
It further includes a reinforcing member that is eclipsed. Also before
The support member is connected to the support member via two or more cantilever arms.
It supports the internal electrodes. In addition, the piece
The holding arm is heated along a thickness direction orthogonal to the substrate.
Two or more types of materials arranged so that their expansion coefficients are symmetric
It is composed of fees.

[Procedure amendment 6]

[Document name to be amended] Statement

[Correction target item name] 0028

[Correction method] Change

[Correction contents]

The substrate in the cantilever arm
And before the cantilever arm is connected
The angle between the side surface of the support member and the support member is obtuse.
Things. Further, the support member may be provided with the cantilever arm.
At the connection portion with the substrate of the cantilever arm
It protrudes to a position higher than the opposite surface.
Also, a surface of the cantilever arm on a side opposite to the substrate.
And the support member projecting higher than the opposite surface.
The angle between the surface and the surface is an obtuse angle.
A surface of the cantilever arm facing the substrate,
Side of the support member to which the cantilever arm is connected
And the angle between them is an obtuse angle.

[Procedure amendment 7]

[Document name to be amended] Statement

[Correction target item name] 0029

[Correction method] Change

[Correction contents]

Further , the contact electrode is connected to the first and second contact electrodes.
2 covered with an insulator film that can be connected to the signal line and the capacitor.
It is. The support member and the cantilever arm are the same
And an integral structure made of the conductive member described above. Said
The support member, the cantilever arm, and the upper electrode are the same.
And an integral structure made of the conductive member described above.

[Procedure amendment 8]

[Document name to be amended] Statement

[Correction target item name] 0030

[Correction method] Change

[Correction contents]

Further , the conductive member is made of a semiconductor material.
It becomes. Further, the semiconductor material may be a single crystal half-crystal.
It is made of a conductor. Further, the semiconductor material is
Consisting of morphous semiconductor or polycrystalline semiconductor
You.

[Procedure amendment 9]

[Document name to be amended] Statement

[Correction target item name] 0031

[Correction method] Change

[Correction contents]

Further , as the substrate, a glass substrate or
This uses a ceramic substrate. Also, the substrate and
Then, a gallium arsenide substrate is used. Also before
The micromachine switch is a phased array antenna.
This is used for the device. Further, the support member is
A plurality of cantilever arms connected to the plurality of support members.
The arm supports the upper electrode.

[Procedure amendment 10]

[Document name to be amended] Statement

[Correction target item name] 0032

[Correction method] Change

[Correction contents]

Further, according to the method of manufacturing a micromachine switch according to the present invention, a first signal line provided on a substrate;
Provided on the substrate and from an end of the first signal line
A second signal line provided at an end with a predetermined gap
Micromachine switch that controls conduction / non-conduction between
Forming a lower electrode on the substrate.
Step, a supporting member having a predetermined height, and the supporting member
Flexible cantilever arm provided on the vehicle and this cantilever arm
Consisting of a contact electrode provided on an insulating member
The contact electrode is opposed to the gap.
At a distance from the first and second signal lines,
Adhering on a substrate, wherein the cantilever arm comprises:
Facing the lower electrode from the connection part with the support member
As a top electrode by having conductivity over the position
Function, and at least from the connection with the support member
Directly in contact with the substrate until the position facing the lower electrode
So that the coefficient of thermal expansion is symmetrical along the intersecting thickness direction
It is composed.

[Procedure amendment 11]

[Document name to be amended] Statement

[Correction target item name] 0034

[Correction method] Change

[Correction contents]

With this configuration, the present invention provides
The thermal expansion coefficient is substantially symmetrical along the thickness direction orthogonal to the substrate surface of the cantilever arm . For this reason, the warpage caused by the strain generated between different materials as in the conventional example is remarkably reduced. Thus, the simplest way to make the coefficient of thermal expansion symmetrical in the thickness direction is to construct the cantilever arm from a single material. In addition, it is of course possible to adopt a vertically symmetric laminated structure.

[Procedure amendment 12]

[Document name to be amended] Statement

[Correction target item name] 0035

[Correction method] Change

[Correction contents]

[0035] Here, in order to suppress warpage of the cantilever arm, in particular cantilever arm near the site to be connected to the support member, and more specifically, to face the lower electrode from the connecting portion between the support member It is effective to make the thermal expansion coefficient symmetrical in the region up to the vicinity of the position as described above. Conversely cantilever
That is, in the vicinity of the tip of the arm , the occurrence of warpage is small even if the coefficient of thermal expansion is not symmetrical along the thickness direction. By the way, when a switch manufactured as a trial was measured, a variation in contact resistance caused by one-sided contact and the like was reduced, and a large number of switches having uniform characteristics could be manufactured.

[Procedure amendment 13]

[Document name to be amended] Statement

[Correction target item name] 0036

[Correction method] Change

[Correction contents]

It has also been found that the change in switch operation is extremely small even when the ambient temperature of the switch changes. Further, according to the configuration of the present invention, the mechanical strength, durability and high-speed operation of the switch are significantly improved as compared with the related art. For example, by making the angle between the cantilever arm and the support member an obtuse angle on the surface on the substrate side, it is possible to prevent the root of the cantilever arm from being broken by stress concentration. Moreover, A has a supporting member pieces
By protruding higher than over arm, it can be the root neighborhood of the structure of the cantilever arm and the vertical direction close to symmetric shape. This makes it possible to make the thermal expansion coefficient distribution in the vicinity of the root of the cantilever arm including the support member symmetrical, and is effective in preventing warping of the cantilever arm .

[Procedure amendment 14]

[Document name to be amended] Statement

[Correction target item name] 0037

[Correction method] Change

[Correction contents]

The fact that the support member protrudes upward is also effective for improving the operation speed of the switch. That is, it is possible to obtain the effect that the speed at which the switch returns from the on state (down state) to the off state (up state) is increased. This is because the support member is cantilevered.
This is because the stress generated at the root portion of the cantilever arm is greater when it projects above the arm . Further, when the switch is turned on / off, the operation is abrupt, so that a phenomenon in which the cantilever arm vibrates up and down (called a bound chattering) may occur. Therefore, in order to terminate such bound chattering quickly, it is necessary to absorb dynamic energy of the cantilevered arm to generate an appropriate stress to the base portion of the cantilever arm to a support member, The supporting member is a piece
A structure that protrudes from the holding arm is effective.

[Procedure amendment 15]

[Document name to be amended] Statement

[Correction target item name] 0038

[Correction method] Change

[Correction contents]

In such a micromachine switch, the cantilever arm has the weakest mechanical structure. Therefore, it is desirable to have a structure that prevents the cantilever arm from being broken by contact with the substrate or the like when the switch is mounted on the substrate in the manufacturing process. Therefore, by setting the protruding structure than has the supporting member piece arm, it is possible to suppress the accidental contact of the cantilever arms, the switch can lower the risk of being destroyed.

[Procedure amendment 16]

[Document name to be amended] Statement

[Correction target item name] 0039

[Correction method] Change

[Correction contents]

Further, even when the in this manner projecting the supporting member than cantilevered arm <br/>, the angle between the cantilever arm support member, to be an obtuse angle on the opposite side of the surface and its substrate Is desirable. This is because the root of the cantilever arm can be prevented from being broken by stress concentration. Incidentally, in the substrate surface side or the opposite side, migraine
When the angle between the holding arm and the support member is an obtuse angle, the angle is preferably in the range of 100 to 170 °, and more preferably in the range of 110 to 150 °. By doing so, it is possible to achieve both the effect of reducing the above-described stress concentration and the effect of generating an appropriate stress to improve the operation speed.

[Procedure amendment 17]

[Document name to be amended] Statement

[Correction target item name] 0040

[Correction method] Change

[Correction contents]

Further, by forming at least a portion including the root portion of the support member and the cantilever arm from the same material, it is possible to reduce distortion between the two members, suppress concentration of stress at one point, and improve strength. The durability against repeated use is improved. Here, when the maintenance member, the cantilever arm, and the upper electrode are made of the same material, the manufacturing process can be simplified.

[Procedure amendment 18]

[Document name to be amended] Statement

[Correction target item name] 0041

[Correction method] Change

[Correction contents]

Further, since a high-temperature process can be used, selection of materials for forming the cantilever arms and the like is widened, various conductors and semiconductors can be used, and the degree of freedom in material selection is increased. In particular, an insulator film manufactured at a high temperature has excellent withstand voltage characteristics and can be said to contribute to the electrical characteristics of a device.

[Procedure amendment 19]

[Document name to be amended] Statement

[Correction target item name] 0042

[Correction method] Change

[Correction contents]

Further, since the degree of freedom in the thickness direction is increased, the width of the arm can be reduced, and the size of the switch can be reduced. The cantilever arm constituting the present invention has conductivity from at least a portion connected to the support member to a position facing the lower electrode, and the conductivity referred to here is a conductor such as a metal. It is not limited to things. In short, it suffices that a voltage can be applied to the position facing the lower electrode through the support member, and almost no current flows in this portion. Therefore, as the material of the cantilever arm up to the position facing the connection portion with the support member, a metal, a semiconductor material, or the like can be widely used. In the case of using a semiconductor material, the presence or absence of impurity addition and the impurity concentration can be varied in a wide range.

[Procedure amendment 20]

[Document name to be amended] Statement

[Correction target item name] 0044

[Correction method] Change

[Correction contents]

[0044]

Next, an embodiment of the present invention will be described with reference to the drawings. In each of the following embodiments, the structure of the cantilever arm 8 has a structure corresponding to FIG. 10 or FIG. 11 described later. That is, the cantilever arms 8, the thermal expansion coefficient along a thickness direction perpendicular to the board surface is constituted by two or more materials which are arranged symmetrically.

[Procedure amendment 21]

[Document name to be amended] Statement

[Correction target item name]

[Correction method] Change

[Correction contents]

[0137]

As described above, according to the present invention, the change of the thermal expansion coefficient on the substrate surface side of the cantilever arm having a small mechanical rigidity and the change of the thermal expansion coefficient on the opposite surface side are symmetrical to each other. . For this reason, the warpage caused by the strain generated between different materials as in the conventional example is remarkably reduced. By the way, when a switch manufactured as a trial was measured, a variation in contact resistance caused by one-sided contact and the like was reduced, and a large number of switches having uniform characteristics could be manufactured.

[Procedure amendment 22]

[Document name to be amended] Statement

[Correction target item name]

[Correction method] Change

[Correction contents]

The manufacturing process can be simplified by manufacturing the support member, the cantilever arm and the upper electrode from the same material.

[Procedure amendment 23]

[Document name to be amended] Statement

[Correction target item name] 0140

[Correction method] Change

[Correction contents]

Further, since a high-temperature process can be used, selection of a material for forming a cantilever arm or the like is widened, various conductors and semiconductors can be used, and the degree of freedom in material selection is increased. In particular, an insulator film manufactured at a high temperature has excellent withstand voltage characteristics and can be said to contribute to the electrical characteristics of a device.

Claims (36)

[Claims] 1. A first signal line provided on a substrate, and a second signal line provided on the substrate and having an end provided at a predetermined gap from an end of the first signal line. A micromachine switch for controlling conduction / non-conduction between the signal line and a signal beam; a flexible beam member supported on the substrate by a support member provided on the substrate in proximity to the gap;
A contact electrode provided at a position on the substrate side of the beam member facing at least the gap, and a lower electrode provided on the substrate so as to face a part of the beam member; Having a conductivity from a connection portion with the support member to a position facing the lower electrode, functions as an upper electrode, and at least from a connection portion with the support member to a position facing the lower electrode. In some areas of the two or more materials arranged so that the thermal expansion coefficient along the thickness direction perpendicular to the substrate surface is symmetrical with respect to the center plane of the beam member parallel to the substrate surface And the contact electrode is provided via an insulating member thicker than an insulating member when provided on the substrate side surface of the beam member. Micromachine switch. 2. A first signal line provided on a substrate and a second signal line provided on the substrate and having an end provided at a predetermined gap from an end of the first signal line. A micromachine switch for controlling conduction / non-conduction between the signal line and a signal beam; a flexible beam member supported on the substrate by a support member provided on the substrate in proximity to the gap;
A contact electrode provided at a position on the substrate side of the beam member facing at least the gap, and a lower electrode provided on the substrate so as to face a part of the beam member; Having a conductivity from a connection portion with the support member to a position facing the lower electrode, functions as an upper electrode, and at least from a connection portion with the support member to a position facing the lower electrode. In a part of the region, the upper electrode is configured so that a thermal expansion coefficient along a thickness direction perpendicular to the substrate surface is symmetric with respect to a center plane of the beam member parallel to the substrate surface. A micromachine switch including a structure including only an insulating member in a region connecting the contact electrode and the contact electrode. 3. A first signal line provided on a substrate and a second signal line provided on the substrate and having an end provided at a predetermined gap from an end of the first signal line. A micromachine switch for controlling conduction / non-conduction between the signal line and a signal beam; a flexible beam member supported on the substrate by a support member provided on the substrate in proximity to the gap;
A contact electrode provided at a position on the substrate side of the beam member facing at least the gap, and a lower electrode provided on the substrate so as to face a part of the beam member; Having a conductivity from a connection portion with the support member to a position facing the lower electrode, functions as an upper electrode, and at least from a connection portion with the support member to a position facing the lower electrode. In a partial region of the beam member is configured so that the coefficient of thermal expansion along the thickness direction perpendicular to the substrate surface is symmetrical with respect to the center plane of the beam member parallel to the substrate surface, and The lower electrode is provided on the substrate between the support member and the gap, and is made of a conductive material thinner than the first and second signal lines. Characterized micromachine switch. 4. An angle between the surface of the beam member on the side of the substrate and the surface of the beam member on the side of the support member to which the beam member is connected is an obtuse angle. A micromachine switch characterized by the following. 5. The support member according to claim 1, wherein the support member protrudes to a position higher than a surface of the beam member opposite to the substrate at a connection portion with the beam member. A micromachine switch, characterized in that: 6. The structure according to claim 5, wherein an angle between a surface of the beam member opposite to the substrate and a surface of the support member protruding higher than the opposite surface is an obtuse angle. And a micromachine switch. 7. The micromachine switch according to claim 5, wherein an angle formed between a surface of the beam member on the substrate side and a side surface of the support member to which the beam member is connected is an obtuse angle. . 8. The beam member according to claim 1, wherein a reinforcing member is provided on a surface of the beam member opposite to a surface on which the contact electrode is provided, facing the contact electrode. A micromachine switch. 9. The micromachine according to claim 1, wherein the contact electrode is covered with an insulator film that can be capacitively connected to the first and second signal lines. switch. 10. The micromachine switch according to claim 1, wherein the support member and at least a part of the beam member have an integral structure made of the same conductive member. 11. The micromachine switch according to claim 1, wherein the conductive member is made of a semiconductor material. 12. The beam member according to claim 2, wherein the beam member is formed of a semiconductor material, and at least a region from a portion where the contact electrode is provided to a portion facing the lower electrode is insulated. A micromachine switch, characterized in that: 13. The micromachine switch according to claim 11, wherein the semiconductor material is a single crystal semiconductor. 14. The micromachine switch according to claim 11, wherein the semiconductor material is an amorphous semiconductor or a polycrystalline semiconductor. 15. The micromachine switch according to claim 1, wherein the substrate is a glass substrate or a ceramic substrate. 16. The micromachine switch according to claim 1, wherein the substrate is a gallium arsenide substrate. 17. The micromachine switch according to claim 1, wherein the micromachine switch is used for a phased array antenna device. 18. The micromachine according to claim 1, further comprising: a plurality of beam members supporting the same contact electrode; and a plurality of support members supporting the beam members. switch. 19. A first signal line provided on a substrate,
A method of manufacturing a micromachine switch for controlling conduction / non-conduction between a second signal line provided on the substrate and having an end provided at a predetermined gap from an end of the first signal line. A step of forming a lower electrode on the substrate, a member comprising a support member having a predetermined height, a flexible beam member provided on the support member, and a contact electrode provided on the beam member Bonding the contact electrode on the substrate in a state where the contact electrode faces the gap and is separated from the first and second signal lines. The beam member is connected to the support member. It functions as an upper electrode by having conductivity from a portion to a position facing the lower electrode, and at least a part of a region from a connection portion with the support member to a position facing the lower electrode, It is composed of two or more types of materials arranged so that the coefficient of thermal expansion along the thickness direction perpendicular to the substrate surface is symmetrical with respect to the center plane of the beam member parallel to the substrate surface, and The contact electrode is provided on a surface of the beam member on the substrate side via an insulating member thicker than an insulating member provided as a part of the mechanical spring. Manufacturing method of micromachine switch. 20. A first signal line provided on a substrate,
A method of manufacturing a micromachine switch for controlling conduction / non-conduction between a second signal line provided on the substrate and having an end with a predetermined gap from an end of the first signal line. Forming a lower electrode on the substrate, a supporting member having a predetermined height, a member including a flexible beam member provided on the supporting member and a contact electrode provided on the beam member; Bonding the contact electrode to the substrate in a state where the contact electrode faces the gap and is separated from the first and second signal lines. The beam member includes a connection portion with the support member. To function as an upper electrode by having conductivity from the position facing the lower electrode, and at least in a partial region from a connection portion with the support member to a position facing the lower electrode, The thermal expansion coefficient along a thickness direction orthogonal to the substrate surface is symmetrical with respect to a center plane of the beam member parallel to the substrate surface, and connects the upper electrode and the contact electrode. A method for manufacturing a micromachine switch, wherein the region is formed only of an insulating member. 21. A first signal line provided on a substrate,
A method of manufacturing a micromachine switch for controlling conduction / non-conduction between a second signal line provided on the substrate and having an end with a predetermined gap from an end of the first signal line. Forming a lower electrode on the substrate, a supporting member having a predetermined height, a member including a flexible beam member provided on the supporting member and a contact electrode provided on the beam member; Bonding the contact electrode to the substrate in a state where the contact electrode faces the gap and is separated from the first and second signal lines. The beam member includes a connection portion with the support member. To function as an upper electrode by having conductivity from the position facing the lower electrode, and at least in a partial region from a connection portion with the support member to a position facing the lower electrode, The thermal expansion coefficient along the thickness direction orthogonal to the substrate surface is symmetrical with respect to the center plane of the beam member parallel to the substrate surface, and the lower electrode is provided with the support member. Manufacturing a micromachine switch provided on the substrate between the gap and the conductive material and having a thickness smaller than a thickness of the first and second signal lines. Method. 22. The angle according to claim 19, wherein an angle between a surface of the beam member on the substrate side and a surface of the support member to which the beam member is connected is obtuse. A method for manufacturing a micromachine switch. 23. The support member according to claim 19, wherein at a connection portion with the beam member, the support member protrudes to a position higher than a surface of the beam member opposite to the substrate. Forming a micromachine switch. 24. The method according to claim 23, wherein an angle between a surface of the beam member opposite to the substrate and a surface of the support member protruding higher than the opposite surface is made obtuse. A method for manufacturing a micromachine switch. 25. The micromachine switch according to claim 24, wherein an angle formed between a surface of the beam member on the substrate side and a side surface of the support member to which the beam member is connected is obtuse. Manufacturing method. 26. The beam member according to claim 19, wherein a reinforcing member is provided on a surface of the beam member opposite to a surface on which the contact electrode is provided, facing the contact electrode. A method for manufacturing a micromachine switch. 27. The manufacturing method of a micromachine switch according to claim 19, wherein the contact electrode is covered with an insulator film that can be capacitively connected to the first and second signal lines. Method. 28. The micromachine switch according to claim 19, wherein the support member and at least a part of the beam member have an integral structure made of the same conductive member. Production method. 29. The method for manufacturing a micromachine switch according to claim 19, wherein the conductive member is formed of a semiconductor material. 30. The method according to claim 20, wherein the beam member is formed of a semiconductor material, and at least a region from a portion where the contact electrode is provided to a portion facing the lower electrode is insulated. A method for manufacturing a micromachine switch. 31. The method according to claim 29, wherein a single crystal semiconductor is used as the semiconductor material. 32. The method according to claim 29, wherein an amorphous semiconductor or a polycrystalline semiconductor is used as the semiconductor material. 33. The method for manufacturing a micromachine switch according to claim 19, wherein a glass substrate or a ceramic substrate is used as the substrate. 34. The method according to claim 19, wherein a gallium arsenide substrate is used as the substrate. 35. The method for manufacturing a micromachine switch according to claim 19, wherein the micromachine switch is used for a phased array antenna device. 36. The micromachine according to claim 19, further comprising: a plurality of beam members that support the same contact electrode; and a plurality of support members that support these beam members. Manufacturing method of switch.