KR100323715B1 - micro switch and method for fabricating the same - Google Patents

Abstract

SUMMARY OF THE INVENTION The present invention provides a micro switch that can be driven at a low voltage and has a low power consumption, comprising: a micro switch having at least one signal line, a ground line, and a wiring pad, the micro switch supporting at least one signal line, a ground line, and a wiring pad; A substrate, a moving plate positioned above the signal line to have a predetermined gap in the signal line, a driver connected to the moving plate and moving the moving plate in contact with the signal line according to an externally applied voltage; It is characterized in that it consists of a second substrate which is fixed to only the edge portion of the driver so that the central portion of the driver is released (released), spaced apart from the first substrate by a predetermined interval. Such a micro switch is driven at low voltage by using piezoelectric force and electrostatic force at the same time, and has high performance.

Description

Micro switch and method for manufacturing the same {micro switch and method for fabricating the same}

The present invention relates to a micro switch, and more particularly, to a micro switch using a piezoelectric force and an electrostatic force at the same time, and a manufacturing method thereof.

Many electronic systems used in the high frequency bands are becoming smaller, lighter, and higher in performance, and thus to replace semiconductor switches such as field effect transistors (FETs) and pin diodes that are used to control signals in the system. Mechanical micro-switches that move mechanically using a new technique called macromachining have been widely studied. There are many disadvantages such as large power loss, distortion, and incomplete on / off isolation when the semiconductor switches are driven. Therefore, mechanically moving microswitches developed using micromachining technology are used in IMT 2000, mobile communication terminals, military wireless communication systems, ideal phases, antenna tuners, receivers, transmitters, phased in the high frequency band. It will be widely used in commercial equipment such as phased array antenna. Tunable capacitors are also desirable for applications in RF (radio frequency) modules or systems.

The mechanically moving microswitches and tunable capacitors developed and proposed so far are driven using electrostatic or magnetic forces. Electrostatically driven switches and tunable capacitors consume less power when operating these devices.

Although almost negligible, the voltage being driven was still large, making it unsuitable for use in mobile terminals or systems. Magnetically driven switches and tunable capacitors can be driven at low voltages, but they consume too much power when operating these devices.

Accordingly, an object of the present invention is to provide a micro switch that can be driven at a low voltage and has low power consumption.

1 is a cross-sectional view of a micro switch according to the present invention.

Figure 2 is a process cross-sectional view showing the manufacturing method of the actuator and the moving plate of the micro switch according to the present invention.

Figure 3 is a process cross-sectional view showing another manufacturing method of the driver and the moving plate of the micro switch according to the present invention.

Figure 4 is a cross-sectional view showing the structure of the driver of the micro switch according to the present invention

Figure 5 is a cross-sectional view showing the operation principle of the driver of the micro switch according to the invention

FIG. 6 is a perspective view showing a structure formed on a first substrate for implementing the resistance type switch shown in FIG. 1A; FIG.

7 is a perspective view showing a structure formed on a first substrate for implementing the capacitive type switch shown in FIG. 1B;

8 is a perspective view showing a structure formed on a first substrate for implementing the capacitive type switch shown in FIG. 1C;

9 is a perspective view showing a structure deformation formed on a first substrate for implementing the resistance type switch shown in FIG.

10 is a perspective view showing a modification of a structure formed on a first substrate for implementing the capacitive type switch shown in FIG.

FIG. 11 is a perspective view showing a modification of a structure formed on a first substrate for implementing the capacitive type switch shown in FIG. 8; FIG.

12 is a cross-sectional view illustrating a method of manufacturing structures formed on the first substrate illustrated in FIGS. 6 and 9.

FIG. 13 is a cross-sectional view illustrating a method of manufacturing structures formed on the first substrate illustrated in FIGS. 7 and 10.

14 is a cross-sectional view illustrating a method of manufacturing a structure formed on the first substrate illustrated in FIGS. 8 and 11.

* Explanation of symbols for main parts of the drawings

11-1: First Substrate 11-2: Second Substrate

12: signal line 13: ground line

14: wiring pad 15: moving plate

16: bend 17: solder bump

18: dielectric material 19: metal material

20: metal seed layer 21: first sacrificial layer

22: second sacrificial layer 23: anchor

31: silicon nitride 32: first metal

33: piezoelectric material 34: second metal

35: silicon oxide 36: high molecular material

37: spacer

Features of the micro switch according to the present invention for achieving the above object is a micro switch having at least one signal line, a ground line and a wiring pad, the first substrate for supporting at least one signal line, ground line and the wiring pad, A moving plate positioned above the signal line so as to have a predetermined constant space on the signal line, a driver connected to the moving plate and moving the moving plate to be in contact with the signal line according to an externally applied voltage; and It is characterized in that it consists of a second substrate which is fixed to only the edge portion of the driver so that the central portion is released (released), and spaced apart from the first substrate by a predetermined interval.

In this case, ground lines are formed at both sides of the signal line, and wiring pads are formed at both sides of the ground line. In addition, the second substrate has a through hole formed in the central portion to release the central portion of the driver and the moving plate, and the driver is connected to the anchor and the moving plate and the anchor attached to the second substrate to apply externally. It is composed of a curved portion for driving the moving plate in accordance with the voltage. Here, the curved portion is made of a piezoelectric material formed between the metals.

Such a micro switch is driven at low voltage by using piezoelectric force and electrostatic force at the same time, and has high performance.

Other objects, features and advantages of the present invention will become apparent from the following detailed description of embodiments with reference to the accompanying drawings.

A preferred embodiment of the micro switch according to the present invention will be described with reference to the accompanying drawings.

1 is a cross-sectional view of a micro switch according to the present invention.

Micro switches are made using a piezoelectric material called PZT, which contracts and expands greatly by an applied voltage in order to move mechanically by piezoelectric force. A cantillever beam made using a PZT film has a 1 μm movement when 1 volt is applied to a DC bias voltage. In order for a microswitch to be used in a system or module, the movable beam needs to move about 2 to 5 μm. Therefore, using the method proposed in the present invention, it is possible to implement a micro switch that moves mechanically below 5 volts. However, since the piezoelectric force is weaker than the electrostatic force, the movable plate 15 may not be in complete contact with the signal line 12 as much as the switch moved by the electrostatic force. In order to overcome this problem, in the present invention, when the moving plate 15 is sufficiently close to the signal line 12 by the piezoelectric force, electrostatic force is applied to make the complete contact with the signal line 12. At this time, the smaller the gap between the moving plate 15 and the signal line 12, the more the applied force can be maximized.

1A is a cross-sectional view of a resistance type micro switch according to the present invention.

As shown in FIG. 1A, there is a first substrate 11-1 supporting at least one signal line 12, a ground line 13, and a wiring pad 14, and a predetermined constant space is provided on the signal line 12. There is a moving plate 15 positioned above the signal line 12. In this case, the ground line 13 is formed on both sides of the signal line 12, and the wiring pads 14 are formed on both sides of the ground line 13.

In addition, there are drivers 16 and 23 connected to the moving plate 15 and moving the moving plate 15 to be in contact with the signal line 12 according to an externally applied voltage. Here, the drivers 16 and 23 are connected to the anchor 23 attached to the second substrate 11-2, the anchor 23 and the moving plate 15, and the moving plates according to an externally applied voltage. It consists of the curved part 16 which drives 15. As shown in FIG. At this time, the curved portion 16 is composed of a metal material and a piezoelectric material formed between the metals.

In addition, only the edges of the drivers 16 and 23 are fixed so that the central portions of the drivers 16 and 23 are released, and spaced apart from the first substrate 11-1 by a predetermined interval. The second substrate 11-2 is formed on the first substrate 11-1. At this time, a through hole is formed in the central portion of the second substrate 11-2 to release the central portion of the drivers 16 and 23 and the moving plate 15. Here, the first substrate 11-1 is made of any one of SiO ₂ , GaAs, and alumina, and the second substrate 11-2 is made of silicon.

1B is a cross-sectional view of a micro switch of a capacitive type according to the present invention.

As shown in FIG. 1B, FIG. 1B is similar to the structure of FIG. 1A, and a dielectric material 18 is formed over the signal line 12.

The moving plate 15 contacts the dielectric material 18 formed on the signal line to switch by on / off impedance.

In this case, the signal line 12 is used as a lower capacitor, and the moving plate 15 in contact with the signal line 12 is used as an upper capacitor.

1C is a cross-sectional view of another capacitive type micro switch in accordance with the present invention.

As shown in FIG. 1C, FIG. 1C is similar to the structure of FIG. 1B, and a metal material 19 is formed over the dielectric material 18. As shown in FIG.

A capacitor is formed by forming a metal material 19 on the dielectric material 18 formed on the signal line 12, and the impedance when the switch is turned on by moving the moving plate 15 on the metal material 19 electrode. This maximizes the switch's ability to maximize its on / off ratio.

In this case, the signal line 12 is used as a lower capacitor, and the metal material 19 is used as an upper capacitor.

Figure 1d is a cross-sectional view showing another embodiment of a micro switch according to the present invention.

As shown in FIG. 1D, FIG. 1D is similar to FIG. 1A, and a spacer 37 having a predetermined thickness is formed between the two substrates 11-2 and the edge portions of the drivers 16 and 23. The spacers 37 are formed to release the central portion of the drivers 16 and 23 and the moving plate 15.

Here, a dielectric material or a metal material / dielectric material may be formed on the signal line shown in FIG. 1D.

2 is a process sectional view showing a method of manufacturing a driver and a moving plate of a micro switch according to the present invention.

2 is a cross-sectional view illustrating a method of manufacturing a driver and a moving plate of the micro switch of FIGS. 1A to 1C.

As shown in FIG. 2A, silicon nitride 31 is formed on the front surface of the second substrate 11-2. At this time, the silicon nitride 31 is used as a membrane of the drivers 16 and 23 and the moving plate 15.

Here, the second substrate 11-2 is made of silicon. Before the silicon nitride 31 is formed, the silicon oxide 35 may be formed on the front surface of the second substrate 11-2.

Next, as shown in FIG. 2B, a first metal 32 is formed on the silicon nitride 31.

As shown in FIG. 2C, a film of the piezoelectric material 33 is formed on the first metal 32, and then cured and patterned.

Subsequently, as illustrated in FIG. 2D, a second metal 34 is formed on the piezoelectric material 33.

Finally, as shown in FIG. 2E, the back surface of the second substrate 11-2 is etched to release the driver and the moving plate from the second substrate 11-2.

Figure 3 is a process cross-sectional view showing another manufacturing method of the driver and the moving plate of the micro switch according to the present invention.

3 is a cross-sectional view illustrating a method of manufacturing a driver and a moving plate of the micro switch of FIG. 1D.

As shown in FIG. 3A, the polymer material 36 is formed on the front surface of the second substrate 11-2 and is patterned to expose the edge region of the second substrate 11-2.

Subsequently, as shown in FIG. 3B, a spacer 37 is formed by forming a material having an etch ratio different from that of the polymer material 36 in the exposed region.

As shown in FIG. 3C, the first metal layer 32 is formed on the polymer material 36 and the spacer 37.

In this case, before forming the first metal layer 32, a silicon nitride layer or a silicon oxide layer / silicon nitride layer may be formed on the front surface of the second substrate 11-2.

3D, the piezoelectric material 33 is formed on the first metal layer 32, and then cured and patterned.

Finally, as shown in FIG. 3E, after forming the second metal layer 34 on the piezoelectric material 33, the polymer material 36 is etched to form a driver and a moving plate on the second substrate 11-2. Release from.

4 is a cross-sectional view showing a curved portion of the micro switch according to the present invention.

As shown in FIG. 4A, the curved portion of the micro switch is formed of a silicon nitride 31, a first metal 32, a piezoelectric material 33, and a second metal 34 sequentially formed.

However, as shown in FIG. 4B, the silicon oxide 35 may be formed under the silicon nitride 31. At this time, the silicon nitride 31 and the silicon oxide 35 are used as the membrane of the driver and the moving plate.

Here, when the curved portion shown in FIG. 4A is exposed by etching the second substrate 11-2, as shown in FIG. 2E, the end of the curved portion 16 that is not fixed because the piezoelectric material 33 has high tensile stress is upward. Baking problem occurs. In order to overcome this problem, as shown in FIG. 3B, when a high compressive stress material such as silicon oxide 35 is used as the membrane together with silicon nitride 31, the stresses coming to the piezoelectric material 33 can be compensated to some extent. This prevents warping.

5 is a perspective view showing the operation principle of the curved portion of the micro-switch according to the present invention.

5A illustrates a curved portion when no voltage is applied.

5B illustrates a curved portion when a voltage is applied.

At this time, the driver and the moving plate are applied to the first metal electrode 32 and the first metal electrode 32 and the second metal electrode 34 constituting the curved portion 16 of the driver shown in FIG. The strain of the piezoelectric material 33 between the second metal electrodes 34 changes so that the curved portion moves and the movable plate moves up and down.

6 to 11 are perspective views showing the structures formed on the first substrate of the micro switch according to the present invention.

FIG. 6 illustrates a structure formed on a first substrate for implementing the resistance type switch shown in FIG. 1A.

As shown in FIG. 6A, the signal line 12 formed vertically at regular intervals and the ground line 13 formed at a predetermined distance on both sides of the signal line 12 and formed at regular intervals on one side of each ground line 13 are formed. There is a wiring pad 14. Solder bumps 17 are formed on the ground lines 13 and the wiring pads 14, respectively.

FIG. 6B is a case where the solder bumps 17 in FIG. 6A are arranged in a line.

FIG. 7 illustrates a structure formed on a first substrate for implementing the capacitive type switch shown in FIG. 1B.

As shown in FIG. 7A, FIG. 7A is a case where the dielectric 18 is between the signal lines 12 having a predetermined interval in FIG. 6A.

As shown in FIG. 7B, FIG. 7B is a case where the dielectric 18 is between the signal lines 12 having a predetermined interval in FIG. 6B.

FIG. 8 illustrates a structure formed on a first substrate for implementing the capacitive type switch shown in FIG. 1C.

As shown in FIG. 8A, FIG. 8A is a case where a metal material 19 is formed on the dielectric 18 in FIG. 7A.

As shown in FIG. 8B, FIG. 8B is a case where a metal material 19 is formed on the dielectric 18 in FIG. 7B.

FIG. 9 illustrates a structure modification formed on a first substrate for implementing the resistance type switch shown in FIG. 6.

As shown in FIG. 8A, two wiring pads 14 are formed vertically on one side of each ground wire 13, and solder bumps 17 are formed on the respective wiring pads 14.

As shown in FIG. 9B, two wiring pads 14 are vertically formed on one side of one ground wire 13, and solder bumps 17 are formed on the respective wiring pads 14.

As shown in FIG. 9C, one wiring pad 14 is formed at one side of one ground wire 13, and a solder bump 17 is formed on the wiring pad 14.

FIG. 10 illustrates a modification of a structure formed on a first substrate for implementing the capacitive type switch shown in FIG. 7.

As shown in FIG. 10, one wiring pad 14 is formed at one side of one ground line 13, and solder bumps 17 are formed on the wiring pad 14 and each ground line 13. If it is.

FIG. 11 shows a variation of the structure formed on the first substrate for implementing the capacitive type switch shown in FIG. 8.

As shown in FIG. 11, one wiring pad 14 is formed at one side of one ground line 13, and solder bumps 17 are formed on the wiring pad 14 and each ground line 13. If it is.

Here, the solder bumps 17 formed on the ground line 13 and the wiring pad 14 may be formed side by side or alternately formed, and the solder bumps 17 may be formed on the ground line 13 and the wiring pad 14. At least one of two) is formed.

12 is a cross-sectional view illustrating a method of manufacturing structures formed on the first substrate illustrated in FIGS. 6 and 9.

FIG. 12 is a structure for implementing the resistance type switch shown in FIG. 1A.

As shown in FIG. 12A, the metal seed layer 20 is formed on the first substrate 11-1.

In this case, the first substrate 11-1 may be quartz, GaAs, alumina, or the like as a substrate having high resistance.

12B, a first sacrificial layer 21 is formed on the metal seed layer 20, and the first sacrificial layer 21 is patterned to form the signal line 12 and the ground line 13. The metal seed layer 20 in the region where the wiring pad 14 is to be formed is exposed.

In this case, the first sacrificial layer 21 uses a polymer material such as photoresist or polyimide.

As shown in FIG. 12C, a metal material is formed on the exposed metal seed layer 20 to form a signal line 12, a ground line 13, and a wiring pad 14.

Next, as shown in FIG. 12D, the second sacrificial layer 22 is formed and patterned on the entire surface to expose a predetermined region of the ground line 13 and the wiring pad 14.

12E, solder bumps 17 are formed on the exposed ground line 13 and the wiring pad 14.

Finally, as shown in FIG. 12F, the remaining first sacrificial layer 21, the second sacrificial layer 22, and the metal seed layer 20 are removed.

FIG. 13 is a cross-sectional view illustrating a method of manufacturing structures formed on the first substrate illustrated in FIGS. 7 and 10.

FIG. 13 is a structure for implementing the capacitive type switch shown in FIG. 1B, in which a dielectric material 18 is formed on the signal line 12 of FIG. 12.

As shown in FIG. 13A, a metal material is formed on the first substrate 11-1 and patterned to form a signal line 12 in a predetermined region.

13B, a dielectric material 18 is formed on the signal line 12.

As shown in FIG. 13C, the metal seed layer 20 is formed on the first substrate 11-1, and the first sacrificial layer 21 is formed on the entire surface including the metal seed layer 20. do.

Subsequently, as shown in FIG. 13D, the first sacrificial layer 21 is patterned to form the metal seed layer 20 in the region where the ground line 13 and the wiring pad 14 are to be formed on both sides of the signal line 12. Expose

As shown in FIG. 13E, a metal material is formed on the exposed metal seed layer 20 to form a ground line 13 and a wiring pad 14.

Subsequently, as shown in FIG. 13F, the second sacrificial layer 22 is formed and patterned on the entire surface to expose a predetermined region of the ground line 13 and the wiring pad 14.

Finally, as shown in FIG. 13G, solder bumps 17 are formed on the exposed ground line 13 and the wiring pad 14, and the remaining first sacrificial layer 21 and the second sacrificial layer ( 22) and the metal seed layer 20 are removed.

14 is a cross-sectional view illustrating a method of manufacturing a structure formed on the first substrate illustrated in FIGS. 8 and 11.

FIG. 14 is a structure for implementing the capacitive type switch shown in FIG. 1C, in which a metal material 19 is formed over the dielectric material 18 of FIG. 13.

As shown in FIG. 14A, a metal material is formed on the first substrate 11-1 and patterned to form a signal line 12 in a predetermined region.

Subsequently, as shown in FIG. 14B, a dielectric material 18 is formed on the signal line 12.

As illustrated in FIG. 14C, the metal seed layer 20 is formed on the first substrate 11-1, and the first sacrificial layer 21 is formed on the entire surface including the metal seed layer 20. do.

Subsequently, as shown in FIG. 14D, the first sacrificial layer 21 over the dielectric material 18 formed on the signal line 12 is removed, and the ground line 13 and the wiring pads are formed on both sides of the signal line 12. The first sacrificial layer 21 is removed to expose the metal seed layer 20 in the region where the 14 is to be formed.

As shown in FIG. 14E, a metal material is formed on a portion where the first sacrificial layer 21 is removed to form a ground line 13 and a wiring pad 14. In addition, a metal material 19 is formed on the dielectric material 18.

Subsequently, as shown in FIG. 14F, the second sacrificial layer 22 is formed and patterned on the entire surface to expose a predetermined region of the ground line 13 and the wiring pad 14.

Finally, as shown in FIG. 14G, solder bumps 17 are formed on the exposed ground line 3 and the wiring pad 14, and the remaining first sacrificial layer 21 and the second sacrificial layer ( 22) and the metal seed layer 20 are removed.

As such, the first substrate 11-1 having the at least one signal line 12, the ground line 13, and the wiring pad 14 illustrated in FIGS. 12 to 14 may include the moving plate 15 and the driver illustrated in FIG. 2. A second substrate 11-2 having (16,23) is attached by the solder bumps 17 so that the movable plate 15 and the signal line 12 face each other with a predetermined space.

Here, when attaching the second substrate 11-2 by the solder bumps 17, a flip-chip bonding technique is used.

As described above, the micro switch according to the present invention and a method of manufacturing the same have the following effects.

First, the micro switch can be driven even at low voltage by simultaneously using the piezoelectric force and the electrostatic force.

Second, by using the piezoelectric force and electrostatic force at the same time it is possible to implement a micro switch with improved reliability.

Those skilled in the art will appreciate that various changes and modifications can be made without departing from the spirit of the present invention.

Therefore, the technical scope of the present invention should not be limited to the contents described in the embodiments, but should be defined by the claims.

Claims (24)

In a micro switch having at least one signal line, a ground line and a wiring pad, A first substrate supporting the at least one signal line, a ground line and a wiring pad; A moving plate positioned above the signal line to have a predetermined gap in the signal line; A driver connected to the moving plate and moving the moving plate to be in contact with the signal line according to an externally applied voltage; And, It is composed of a second substrate which is fixed to only the edge portion of the driver so that the central portion of the driver is released (released), and is spaced apart from the first substrate by a predetermined interval. Micro switch. The method of claim 1, A ground switch is formed on both sides of the signal line, and micro pads are formed on both sides of the ground line. The method of claim 1, The second substrate is a micro switch, characterized in that the through-hole is formed in the central portion to release the central portion and the moving plate of the driver. The method of claim 1, And a spacer having a predetermined thickness is formed between the second substrate and an edge portion of the driver to release a central portion of the driver and a moving plate. The method of claim 1, The driver An anchor attached on the second substrate; And a curved part connected to the anchor and the moving plate to drive the moving plate according to an externally applied voltage. The method of claim 5, The curved portion And a piezoelectric material formed between the metals. The method of claim 6, The micro switch of any one of the metals, characterized in that the silicon nitride layer or silicon oxide layer / silicon nitride layer is formed. The method of claim 7, wherein And the silicon nitride layer or silicon oxide layer / silicon nitride layer is formed on a metal surface opposite to the direction in which the metals are bent. The method of claim 1, And the second substrate is attached to the ground line and the wiring pad by solder bumps. The method of claim 9, The solder bumps formed on the ground line and the wiring pad, respectively, are formed side by side or alternately formed with each other micro switch. The method of claim 9, And at least two solder bumps are formed in at least one of the ground wire and the wiring pad. The method of claim 1, And a dielectric material or a metal material / dielectric material formed on the signal line. The method of claim 12, When the dielectric material is formed on the signal line, the signal line is used as the lower electrode of the capacitor and the moving plate in contact with the signal line is used as the upper electrode. The method of claim 12, And a metal material / dielectric material stacked on the signal line, wherein the signal line is used as a lower electrode of a capacitor and the metal material is used as an upper electrode. 1. A method of manufacturing a micro switch comprising a first substrate having at least one signal line, a ground line, and a wiring pad, and a second substrate having a moving plate driven by a driver. Forming a signal line, a ground line, and wiring pads in a predetermined area on the first substrate, and forming an adhesive material on the ground line and the wiring pads; And a second step of attaching the second substrate to the adhesive material such that the movable plate faces the signal line in a predetermined space. The method of claim 15, Wherein the first substrate is made of SiO ₂ , GaAs, or alumina, and the second substrate is made of silicon. The method of claim 15, The first step is Forming a metal seed layer and a first sacrificial layer on the first substrate; Patterning the first sacrificial layer to expose a metal seed layer in a region where the signal line, the ground line, and the wiring pad are to be formed; Forming a metal material on the exposed metal seed layer to form the signal line, the ground line and the wiring pad; Forming and patterning a second sacrificial layer on a front surface to expose a predetermined area of the ground line and the wiring pad; Forming an adhesive material on the exposed ground wire and wiring pad; And removing the remaining first and second sacrificial layers and the seed metal layer. The method of claim 15, The first step is Forming and patterning a metal material on the first substrate to form the signal line in a predetermined region; Forming a dielectric material over the signal line; Forming a metal seed layer on the first substrate, and forming a first sacrificial layer on the entire surface including the metal seed layer; Patterning the first sacrificial layer to expose a metal seed layer in a region where a ground line and a wiring pad are to be formed on both sides of the signal line; Forming a metal material on the exposed metal seed layer to form a ground line and a wiring pad; Forming and patterning a second sacrificial layer on a front surface to expose a predetermined area of the ground line and the wiring pad; Forming an adhesive material on the exposed ground wire and wiring pad; And removing the remaining first and second sacrificial layers and the seed metal layer. The method of claim 18, And forming a metal layer on the dielectric material after forming the dielectric material on the signal line. The method of claim 15, The second step is Sequentially forming and patterning a first metal layer, a piezoelectric material, and a second metal layer on a front surface of the second substrate to form the driver and the moving plate; And etching the predetermined region behind the second substrate to release the driver and the moving plate from the second substrate. The method of claim 20, And forming a silicon nitride layer or a silicon oxide layer / silicon nitride layer on the front surface of the second substrate before forming the first metal layer. The method of claim 15, The second step is Forming a sacrificial layer on the front surface of the second substrate and patterning the semiconductor substrate to expose an edge region of the second substrate; Forming a material having an etch ratio different from that of the sacrificial layer in the exposed region; Sequentially forming and patterning a first metal layer, a piezoelectric material, and a second metal layer on the entire surface including the sacrificial layer to form the driver and the moving plate; And etching the sacrificial layer to release the driver and the moving plate from the second substrate. The method of claim 20, And forming a silicon nitride layer or a silicon oxide layer / silicon nitride layer on the front surface of the second substrate before forming the first metal layer. The method of claim 15, Attaching the second substrate to the adhesive material using a flip-chip bonding technique.