JP2900861B2 - Movable piece block - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a movable piece block applied to an electrostatic relay or the like using electrostatic force as a driving source.

[0002]

Conventionally, as an electrostatic relay, an insulating film of silicon oxide (SiO ₂₎ is formed as a mask 102 on a semiconductor substrate 101 made of a silicon single crystal wafer (Si) as shown in Figure 1 4, A conductive thin film 103 is formed on the main surface of the substrate 101 through the mask 102 by vapor deposition or sputtering, and the conductive thin film 103 is used to form a driving electrode layer 104 and a movable contact piece 1.
05 and a fixed contact layer 107
Are formed, and a concave portion 108 is formed by etching on the main surface of the substrate 101 so as to face the driving electrode layer 104, so that a part of the mask 102 is formed as a movable piece 109 made of a cantilever. Ru formed was Monogaa (e.g., JP 55-109341 and JP 5
8-201218).

That is, when a DC voltage V is applied between the driving electrode layer 104 and the substrate 101, an electrostatic attraction force acts between the driving electrode layer 104 and the substrate 101, and the movable piece 109 is moved.
Is displaced downward, and the movable contact piece 105 comes into contact with the fixed contact layer 107. The silicon substrate 101 can be finely processed by a semiconductor thin film forming means, which is suitable for miniaturization.

[0004]

However, since the movable piece 109 is formed of an insulating thin film of silicon oxide having a thickness of about 1 μm, the mechanical strength of the movable piece 109 is low. When it is violent or when the liquid is put into and taken out of the liquid tank randomly, the liquid may be broken due to vibration during use. Further, if the cleaning after the etching process is insufficient, the movable piece 109 may be adsorbed to the bottom surface of the recess 108 due to the surface tension of the liquid.

In particular, since the movable piece 109 is extremely thin, warpage occurs due to a difference in linear expansion coefficient between the two when the drive electrode layer 104 is formed. Is a factor that greatly changes. Further, in order to keep the depth dimension of the concave portion 108 related to the driving force at a constant small value, it is necessary to stop the etching in the middle, so that the silicon substrate 101 is highly doped with P ⁺ . And other complicated techniques are also required, and manufacturing is extremely difficult.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and it is an object of the present invention to provide a stable and highly sensitive movable piece block which is easy to perform fine processing, has excellent productivity, can enhance mechanical strength, and is stable. The purpose is.

[0007]

According to a first aspect of the present invention, a movable piece block includes a frame formed from a semiconductor substrate, a movable piece formed in the frame, and a substantially central portion of the movable piece .
The movable piece are integrally formed on both sides and a hinge portion of a pair of displaceable hinge supported by the frame portion, the movable
The piece is configured to perform a seesaw operation around the hinge.
It is characterized by having been done . In the movable piece block according to the second aspect of the present invention , the movable piece is formed to be thinner than the frame portion.
It is characterized by having. The movable piece according to the invention of claim 3
The block has a thin part at the hinge of the movable piece
It is characterized by. Movable piece block according to the invention of claim 4
It is especially that it has formed a switching interrupt portion to the hinge portion of the movable piece
Sign.

[0008]

According to the first aspect of the present invention, the movable piece block is half
Since microfabrication is easy to form from the conductive substrate and the movable piece is integrally supported in the frame, this frame functions as a protective frame for the movable piece and enhances mechanical strength. Can be folded in the manufacturing process.
There is no risk of loss.

Further, since the movable piece and the hinge are integrally formed in the frame of the movable piece block, manufacturing and assembling operations can be performed easily and efficiently. In addition, the above-mentioned Allowed
Can the moving piece block be formed separately from the substrate?
Change the distance between the electrodes by selecting the spacer means.
The desired driving force can be obtained. Moreover, the movable piece
It is configured to operate seesaw around the hinge part as an axis.
Provides a stable and highly sensitive movable piece block
can do. According to the invention of claim 2, the movable piece is
By forming it thinner than the frame,
Position, and the movable piece is protected by a frame.
You. The movable piece block according to the invention of claim 3 is a movable piece block.
By forming a thin part in the hinge part, the movable piece
Displacement can be facilitated. According to the invention of claim 4
The moving piece block forms a notch in the hinge of the movable piece
To increase the displacement stroke of the movable piece.
can do.

Further, since the movable piece and the hinge are integrally formed in the frame of the movable piece block, manufacturing and assembling operations can be performed easily and efficiently. Furthermore, by specifying the plane orientation of the semiconductor substrate made of a single crystal, the movable piece block is subjected to fine processing of the movable piece and the like with higher precision, and the movable piece and the hinge portion which is a pivot portion thereof are removed. The movable piece can be easily displaced and its operation performance can be improved by making it thinner or forming a notch or the like in the hinge part itself.

[0010]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is an exploded perspective view showing an example of a movable piece block according to the present invention applied to an electrostatic relay, and FIG.
FIG. 2 is a sectional view taken along line II - II of FIG.

In FIG. 1, reference numeral 1 denotes an electrically insulating substrate, for example, a rectangular glass substrate, and a pair of front and rear driving electrode layers 2 located on the main surface thereof at a central portion in the front and rear direction (longitudinal direction). , 3 are juxtaposed. Reference numerals 4 and 5 denote a pair of front-side fixed contact layers formed on the main surface of the substrate 1 in front of the front drive electrode layer 2, and reference numerals 6 and 7 denote the rear drive electrodes. A pair of fixed contact layers on the rear side formed on the main surface of the substrate 1 behind the layer 3. The drive electrode layers 2 and 3 and the fixed contact layers 4 to 7 are formed by known means such as vapor deposition.

Reference numeral 8 denotes a movable piece block. The movable piece block 8 is formed from a semiconductor single crystal substrate, for example, a rectangular plate-like silicon single crystal wafer, and is a mixture of glass rods 9 and 9 as spacer means and an adhesive 10. , And is pressed and fixed to the main surface side of the substrate 1. As the spacer means, particles of alumina (Al ₂ O ₃ ) may be used instead of the glass rods 9, 9. The movable piece block 8 is formed with a rectangular movable piece 11 surrounded by a square frame portion 8A. The movable piece 11 is coupled between a center portion in the front-rear direction and the frame portion 8A. Hinge part 12
The front piece 11A and the rear piece 11B are set to be swingable about.

The movable piece 11 is formed in a desired shape by forming an insulating thin film 13 of, for example, silicon oxide (FIG. 2) in a predetermined pattern as a mask on the upper surface of the wafer and etching the wafer. You. The two pieces 11A and 11B of the movable piece 11 form a counter electrode for driving together with the electrode layers 2 and 3, respectively. 14 and 15 are front pieces 11 of the movable piece 11
The movable contact layer 14 is fixed to the lower surface of each of the front contact portions A and the rear piece portion 11B via an insulating thin film 16 of silicon oxide (FIG. 2), and the movable contact layer 14 is provided between the front fixed contact layers 4 and 5. The movable contact layer 15 is set for opening and closing and for opening and closing the rear fixed contact layers 6 and 7. The movable piece 1
1 and the movable contact layers 14 and 15, the movable piece block 8 is attached to the main surface side of the substrate 1 by the glass rods 9 and
In this case, it is recommended to set a positioning mark 17 shown in FIG. 3 on the back surface of the substrate 1 in order to ensure the accuracy of the alignment between the two.

Next, the operation of the above configuration will be described. When a DC voltage is applied between the front piece 11A of the movable piece 11 and the drive electrode layer 2, an electrostatic attraction force is generated between the front piece 11A and the electrode layer 2, and the front piece 11A is displaced by bending toward the electrode layer 2 with the hinge portion 12 as a fulcrum, so that the movable contact layer 14 comes into contact with the fixed contact layers 4 and 5, and the space between the fixed contact layers 4 and 5 is closed. When the application of the DC voltage is stopped, the front piece 11A returns to the original state by the torsion restoring force of the hinge 12 and the fixed contact layers 4 and 5 are opened.
When a DC voltage is applied between the rear piece 11B of the movable piece 11 and the driving electrode layer 3, the rear piece 11B performs substantially the same operation as the front piece 11A.

According to the above configuration, since the movable piece block 8 is formed from a silicon single crystal wafer, it is easy to perform fine processing, and the movable piece 11 is integrally supported in the frame portion 8A. The portion 8A functions as a protective frame for the movable piece 11 and can enhance mechanical strength, so that there is no possibility of the movable piece 11 being broken in a manufacturing process.

Since the movable piece block 8 has the movable piece 11 and the hinge portion 12 integrally formed in the frame portion 8, the manufacturing and assembling work can be performed easily and efficiently.
Further, since the movable piece block 8 is formed separately from the substrate 1, a desired driving force can be obtained by changing the distance between the electrodes by selecting the spacer means 9. By the way, the movable piece 11 is obtained by finely processing the movable piece block 8 by etching, and anisotropic etching is employed for further precise fine processing.

When the movable piece block 8 is formed by anisotropic etching of a silicon single crystal wafer, it is important to note the following. That is, when the upper surface of the movable piece block 8 is the (110) plane, the orientation fuzzet (hereinafter, referred to as OF) is (00).
1) When it is a surface, if the movable piece 11 is manufactured in a rectangular shape,
As shown in FIG. 4A, although the side 11a parallel to the OF can be formed into a precise straight line, the side 11b perpendicular to the OF is indented. If the mold is obliquely formed with respect to the OF, a complicated shape is obtained. Therefore, (10
When the 0) plane is used, it is difficult to obtain the movable piece 11 having a precise shape.

On the other hand, when the upper surface of the movable piece block 8 is the (100) plane, if it is formed obliquely with respect to the OF, as shown by the broken line in FIG. Parallel and vertical sides 11a, 11
A precise straight line is obtained for b, and matches the mask pattern with high precision. Therefore, in consideration of the above plane orientation, the movable piece 1 has high dimensional accuracy and high three-dimensional reproducibility of the shape.
No. 1 can be easily obtained, and this can surely eliminate the risk of malfunction due to formation of burrs on the mask or residual silicon. In addition to the (100) plane, (010), (00)
Each surface such as 1) is equivalent, and these are the surface group [100].
Is a common property. Also, for the OF, the movable piece 1
It is preferable to dispose 1 in a direction perpendicular or parallel to the OF formed parallel to the surface group [011]. Note that the surface group [011] includes other surfaces such as a (011) surface having common properties.

If the movable piece 11 is formed as thin as possible, the movable piece 11 is easily displaced and the operability is improved. This can be easily realized by etching in two steps from the upper and lower surfaces of the movable piece block 8, as shown in FIGS. 5A and 5B. 5A is formed by anisotropic etching from both directions of arrows a and b.
The part indicated by B is formed by isotropic etching from the direction of arrow a and formed by anisotropic etching from the direction of arrow b.
Is formed.

Normally, a depth d for controlling the thickness from the direction of arrow a
After performing only one etching, etching is performed to a depth d2 in the direction of arrow b. When etching one side,
On the other side, a stainless steel plate or the like is stuck via wax or the like to prevent influence from one direction. It should be noted that if the etching is performed first in the direction of the arrow b, the concave portion 8B (FIGS. 5A and 5B) becomes a negative pressure, and the movable piece 11 may be deformed or broken.

FIGS. 6 and 7 show the movable piece block 8 manufactured by the two-stage etching method shown in FIGS. 5A and 5B applied to an electrostatic relay. In this case, the movable piece 11 is formed thinner than the frame portion 8A, so that the movable piece 11 can be easily displaced.
There is an advantage that the movable piece 11 is protected by the frame 8A.
Further, in order to facilitate the displacement of the movable piece 11, for example, as shown in FIG. 8, a thin portion 18 may be formed in the hinge portion 12 by isotropic etching.

Further, as shown in FIG.
If the notch 19 is formed in the movable piece 11 along, the stroke for displacing the movable piece 11 can be increased.

By the way, during the operation of the movable piece 11, per one side substrate horizontally both corners or the like of the distal end side, if there is a risk of damaged by the repetition, the chamfered portion 21 as shown in FIG. 1 0 What is necessary is just to form. When burrs or the like are formed on the silicon oxide insulating thin film 16 as a mask corresponding to the corners, the movable contact layer 14
There is a possibility that the corners of (15) are peeled off and short-circuited. In this case, if a silicon oxide thin film obtained by thermal oxidation is used as a mask, there is no possibility that flash will occur immediately after etching.

[0024] Of course, the portions corresponding to the two corners of the movable contact layer 14 (15), by forming the cutout portion 22 as shown in Figure 1 0, the risk of separation of the movable contact layer 14 (15) Therefore, occurrence of a short circuit accident can be effectively prevented. When Figure 1 1 is for forming the movable piece 11, the upper and lower surfaces by performing anisotropic etching alternately, according to the pattern of the insulating film 13, 16 of silicon oxide on its distal end side, the chamfered portion 23 at its upper and lower surfaces This is effective as a measure for preventing the movable piece 11 from being damaged.

FIG. 1 2 and 1 3 is a diagram showing by applying another example of the movable piece block 8 according to the invention in an electrostatic relay. That is, the movable piece block 8 is provided with movable contact fixing arm pieces 24A, 24A and 24B, 24B protruding forward from the respective distal ends on the front and rear pieces 11A, 11B of the movable piece 11. It is a coupled one. The movable contact layers 14 and 15 are respectively formed by the arm pieces 24A and 24B to form front and rear pieces 11A and 11B.
In order to reliably contact the fixed contact layers 4 and 5 before B,
There is no danger of short-circuit, and a sufficient contact pressure can be easily obtained by the span of the arm pieces 24A, 24B.

Further, according to the above embodiment, the recessed portion 1b having a step difference from the peripheral portion 1a is formed on the substrate 1 and the bottom surface of the recessed portion 1b is used as the main surface of the substrate 1. 1
a is configured as a spacer means, and the number of parts is reduced. The shapes of the arm pieces 24A and 24B can be arbitrarily changed.

[0027]

As described above , according to the first aspect of the present invention,
For example, since the movable piece block is formed from a semiconductor substrate, fine processing is easy, and the movable piece is integrated into the frame.
This frame part serves as a protective frame for the movable piece.
Function and enhance the mechanical strength , the manufacturing process
There is no risk of breakage of the movable piece in
The movable piece and the hinge part are integrally formed inside the
Construction and assembly work can be performed easily and efficiently.
Since it can be formed separately from the substrate, the spacer means
Desired driving force by changing the distance between electrodes by selecting
be able to. Moreover, the movable piece pivots on the hinge portion.
Because it is configured to operate as a seesaw,
Can provide a fixed and highly sensitive movable piece block
You. According to the second and third aspects of the present invention, the movable piece is referred to as a frame.
Or a thin part at the hinge of the movable piece.
This makes it easy to displace the movable piece.
it can. According to the invention of claim 4, the hinge of the movable piece is provided.
By forming a notch in the part, the movable piece can be transformed.
The position stroke can be increased.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view showing an example of a movable piece block according to the present invention applied to an electrostatic relay.

FIG. 2 is a sectional view taken along the line II - II in FIG.

FIG. 3 is a plan view illustrating an example of a manufacturing process of a movable piece block according to the present invention.

FIG. 4A is a plan view illustrating an example of a manufacturing step of the movable piece block according to the present invention.

FIG. 4B is a plan view illustrating another example of the manufacturing step of the movable piece block according to the present invention.

FIG. 4C is a plan view illustrating another example of the manufacturing step of the movable piece block according to the present invention.

FIG. 5A is a sectional view showing another example of the movable piece block according to the present invention.

FIG. 5B is a sectional view showing another example of the movable piece block according to the present invention.

FIG. 6 is an exploded perspective view showing another example of the movable piece block according to the present invention applied to an electrostatic relay.

FIG. 7 is a sectional view taken along line BB of FIG. 6;

FIG. 8 is a perspective view showing a different example of the movable piece block according to the present invention.

FIG. 9 is a perspective view showing another different example of the movable piece block according to the present invention.

FIG. 10 is a perspective view of a main part showing a modification of the movable piece block according to the present invention.

FIG. 11 is a perspective view of a main part showing another example of a different movable piece block according to the present invention.

FIG. 12 is an exploded perspective view showing another example of the movable piece block according to the present invention applied to an electrostatic relay .

FIG. 13 is a sectional view taken along line CC of FIG . 6 ;

FIG. 14 shows an example of a conventional movable piece block as an electrostatic relay.
It is sectional drawing shown about .

[Explanation of symbols]

 Reference Signs List 8 movable piece block 8A frame part 11 movable piece 12 hinge part 18 thin part 19 cut part

────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Yoshitaka Sunagawa 10-storey, Todo-cho, Hanazono-ku, Kyoto-shi, Kyoto OMRON Corporation (56) References JP-A-57-197728 (JP, A) JP-A-62 -123622 (JP, A) JP-A-58-201218 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) H01H 59/00

Claims (4)

(57) [Claims] 1. A frame formed from a semiconductor substrate, a movable piece formed in the frame, and a substantially central portion of the movable piece.
The movable piece are integrally formed on the side and a hinge portion of a pair of displaceable hinge supported by the frame portion, the movable piece
Is configured to operate seesaw around the hinge
A movable piece block characterized by being made . 2. The movable piece block according to claim 1, wherein the movable piece is formed thinner than a frame portion. 3. A movable piece block according to claim 1 or 2, characterized in that the formation of the thin portion to the hinge portion of the movable piece. 4. The movable piece block according to claim 1, wherein a cut portion is formed in a hinge portion of the movable piece.