TWI657039B - Manufacturing method of micro-electromechanical pump - Google Patents

Abstract

A method of manufacturing a microelectromechanical pump, comprising the steps of: (a) providing a first substrate, thinning the first substrate to a first thickness; (b) forming a first oxide layer on the first substrate, and etching the first substrate Forming at least one air inlet hole; (c) providing a second substrate, thinning the second substrate to a second thickness; (d) forming a second oxide layer on the second substrate, and etching a through hole on the second substrate; e) bonding the second substrate to the first substrate, and the first oxide layer is located between the first substrate and the second substrate, the air inlet hole and the through hole are misaligned; (f) providing the third substrate, and thinning the third substrate to a third thickness, and etching at least one gas channel on the third substrate; (g) disposing the piezoelectric component on the third substrate; (h) bonding the third substrate to the second substrate, and the second oxide layer is on the second substrate The gas passage and the perforation are misaligned with the third substrate.

Description

Microelectromechanical pump manufacturing method

The present invention relates to a method of manufacturing a microelectromechanical pump, and more particularly to a method of fabricating a microelectromechanical pump through a semiconductor process.

At present, in various fields, such as medicine, computer technology, printing and energy, the products are developing in the direction of refinement and miniaturization. Among them, products such as micro pump, sprayer, inkjet head and industrial printing device are included. The pump used to transport fluids is a key component, so how to break through its technical bottlenecks with innovative structures is an important part of development.

With the rapid development of technology, the application of fluid delivery devices is becoming more and more diversified. For industrial applications, biomedical applications, medical care and electronic heat dissipation, and even the most popular wearable devices, it can be seen. Conventional pumps have gradually become the trend toward miniaturization of devices and maximization of flow.

However, although the current miniaturized pump has been continuously improved to make it miniaturized, it still cannot break through the millimeter level and then the pump is reduced to the micron level. Therefore, how to reduce the pump to the micron level and complete it for the purpose of this case The main subject.

The main purpose of the present invention is to provide a method of manufacturing a microelectromechanical pump for manufacturing a nanometer-scale microelectromechanical pump to reduce the volume limitation for the pump.

In order to achieve the above object, a generalized embodiment of the present invention provides a method for fabricating a microelectromechanical pump, comprising the steps of: (a) providing a first substrate, and thinning the first substrate to a first thickness; b) forming a first oxide layer on the first substrate, and the first substrate etches at least one air inlet hole; (c) providing a second substrate, and thinning the second substrate to a second thickness; d) forming a second oxide layer on the second substrate, and etching a via hole on the second substrate; (e) bonding the second substrate to the first substrate, and the first oxide layer is located at the first Between a substrate and the second substrate, the air inlet hole and the through hole are misaligned; (f) providing a third substrate, thinning the third substrate to a third thickness, and etching at least the third substrate a gas channel; (g) a piezoelectric component is disposed on the third substrate; (h) the third substrate is bonded to the second substrate, and the second oxide layer is located on the second substrate and the third substrate The gas passage is misaligned with the perforation.

100‧‧‧Microelectromechanical pump

1‧‧‧First substrate

11‧‧‧Air intake

12‧‧‧ first upper surface

13‧‧‧First lower surface

2‧‧‧second substrate

21‧‧‧Perforation

22‧‧‧Second upper surface

23‧‧‧Second lower surface

24‧‧‧Resonance

25‧‧‧ Fixed Department

3‧‧‧First oxide layer

31‧‧‧Intake runner

32‧‧‧Confluence chamber

4‧‧‧ Third substrate

41‧‧‧ gas passage

42‧‧‧ third upper surface

43‧‧‧ Third lower surface

44‧‧‧Vibration Department

45‧‧‧The outer part

46‧‧‧Connecting Department

5‧‧‧Second oxide layer

51‧‧‧ gas chamber

6‧‧‧ Piezoelectric components

61‧‧‧ lower electrode layer

62‧‧‧ piezoelectric layer

63‧‧‧Insulation

64‧‧‧Upper electrode layer

a~h‧‧‧Steps in the manufacturing method of MEMS pump

G1~g4‧‧‧Steps for manufacturing piezoelectric components

FIG. 1 is a schematic flow chart of a manufacturing method of a microelectromechanical pump according to the present invention.

Figure 2 is a schematic cross-sectional view of the microelectromechanical pump in this case.

Figure 3 is a flow chart showing the manufacture of the piezoelectric component of the microelectromechanical pump.

4A to 4C are schematic views of the operation of the microelectromechanical pump of the present invention.

Fig. 5 is a schematic view showing the top view of the third substrate of the microelectromechanical pump of the present invention.

Some exemplary embodiments embodying the features and advantages of the present invention are described in detail in the following description. It should be understood that the present case can have various changes in different aspects, and it does not deviate from this. The scope of the case, and the descriptions and illustrations thereof are used in the nature of the description, and are not intended to limit the case.

The present invention provides a manufacturing method of a microelectromechanical pump, which can be used in the fields of medical technology, energy, computer technology or printing, for guiding fluids and adding or controlling The flow rate of the fluid. Please refer to FIG. 1 and FIG. 2 at the same time. FIG. 1 is a schematic flow chart of the manufacturing method of the microelectromechanical pump 100 of the present invention, and FIG. 2 is a microelectromechanical pump manufactured by the manufacturing method of the microelectromechanical pump 100 of the present invention. 100 is a schematic cross-sectional view; the flow of the manufacturing method of the MEMS pump 100 of the present invention is summarized as follows: Step a, providing a first substrate 1 to thin the first substrate 1 to a first thickness; Step b, The first substrate 1 forms a first oxide layer 3, and the first substrate 1 etches at least one air inlet hole 11; in step c, a second substrate 2 is provided, and the second substrate 2 is thinned to a second thickness (not shown); in step d, a second oxide layer 5 is formed on the second substrate 2, and a through hole 21 is etched on the second substrate 2; in step e, the second substrate 2 is bonded to the first substrate a substrate 1 , and the first oxide layer 3 is located between the first substrate 1 and the second substrate 2 , the air inlet hole 11 is offset from the through hole 21; in step f, a third substrate 4 is provided, The third substrate 4 is thinned to a third thickness, and at least one gas passage 41 is etched from the third substrate 4; step g, at the third base 4, a piezoelectric component 6 is disposed; and step h, the third substrate 4 is bonded to the second substrate 2, and the second oxide layer 5 is located between the second substrate 2 and the third substrate 4, the gas The passage 41 is misaligned with the perforation 21.

First, as shown in step a, the first substrate 1 is first provided, and the first substrate 1 is thinned to a first thickness (not shown) by grinding, etching or cutting, and the first substrate 1 is thin. After the first thickness, the first upper surface 12 and the first lower surface 13 are formed.

Continuing to perform step b, a first oxide layer 3 is formed on the first upper surface 12 of the first substrate 1, and at least one is formed by dry etching or wet etching on the first lower surface 13 of the first substrate 1. The air hole 11 , the air inlet hole 11 will penetrate the first upper surface 12 and the first lower surface 13 of the first substrate 1 , and in the embodiment, the aperture of the air inlet hole 11 is from the first lower surface 13 to the first upper surface 12 shows a tapered conical shape. In addition, step b further includes forming at least one inlet flow path 31 and a confluence chamber 32 on the first oxide layer 3 by an etching process.

Further, as shown in step c, a second substrate 2 is provided, and the second substrate 2 is thinned to a second thickness (not shown) by grinding, etching or cutting, and the second substrate 2 is thinned to a second thickness. There is a second upper surface 22 and a second lower surface 23.

Further, as shown in step d, a second oxide layer 5 is formed on the second upper surface 22 of the second substrate 2, and a through hole 21 is etched through the center of the second substrate 2 through an etching process, and the through hole 21 will penetrate through the second surface. The surface 22 and the second lower surface 23; further, in the step d, the central region of the second oxide layer 5 is formed into a gas chamber 51 by using an etching process, and the gas chamber 51 and the through hole 21 of the second substrate 2 are connected to each other. .

Further, as shown in step e, the second substrate 2 is bonded to the first substrate 1, and the second lower surface 23 of the second substrate 2 is bonded to the first oxide layer 3 on the first upper surface 12 of the first substrate 1, The first oxide layer 3 is disposed between the first substrate 1 and the second substrate 2. At this time, the through holes 21 on the second substrate 2 and the air inlet holes 11 of the first substrate 1 are disposed in a dislocation manner; wherein, the first The confluence chamber 32 of the oxide layer 3 and the perforation 21 communicate with each other, and the intake passage 31 of the first oxide layer 3 is the same as the number of the intake holes 11 of the first substrate 1, and the positions correspond to each other, and the intake passage 31 is One end is connected to the air inlet hole 11 and communicates with the air inlet hole 11, and the other end of the intake air flow path 31 communicates with the bus flow chamber 32, so that the gas can be respectively passed through the air inlet hole 11 of the first substrate 1, and then passed through. The corresponding intake runner 31 then converges in the confluence chamber 32.

As shown in step f, a third substrate 4 is provided, and the third substrate 4 is also thinned to a third thickness (not shown) by grinding, etching or cutting, etc., so that the third substrate 4 has a third on The surface 42 and a third lower surface 43 are etched into the third substrate 4 to form a plurality of gas passages 41. The gas passages 41 penetrate through the third upper surface 42 and the third lower surface 43 of the third substrate 4, and define a vibration. The portion 44, an outer peripheral portion 45, and three portions of the plurality of connecting portions 46 (shown in FIG. 5) are respectively a vibrating portion 44 surrounded by the gas passage 41, surrounding the outer peripheral portion 45 at the periphery of the gas passage 41, and A plurality of connecting portions 46 are provided between the gas passages 41 and connected between the vibrating portion 44 and the outer peripheral portion 45. In the present embodiment, the number of the gas passages 41 is four, and the number of the connecting portions 46 is also four; and in step g, a piezoelectric assembly 6 is formed on the third upper surface 42 of the third substrate 4.

Finally, as shown in step h, the third lower surface 43 of the third substrate 4 is bonded to the second oxide layer 5 on the second upper surface 22 of the second substrate 2, so that the second oxide layer 5 is located on the second substrate 2 and Between the third substrate 4, the perforations 21 of the second substrate 2 and the gas passages 41 of the third substrate 4 are disposed in a dislocation manner, wherein the gas chambers 51 of the second oxide layer 5 and the perforations 21 of the second substrate 2 and The gas chambers 51 of the second oxide layer 5 are in communication with each other. After the above steps are completed, the microelectromechanical pump 100 of a micron size can be manufactured.

In addition, please refer to FIG. 2 and FIG. 3 at the same time. The process flow of forming the piezoelectric component 6 on the third substrate 4 in the foregoing step g is summarized as follows: step g1, depositing the electrode layer 61; step g2, under A piezoelectric layer 62 is deposited on the electrode layer 61; in step g3, an insulating layer 63 is deposited on a portion of the piezoelectric layer 62 and a portion of the lower electrode layer 61; in step g4, the insulating layer 63 is not deposited on the piezoelectric layer 62. An upper electrode layer 64 is deposited on the region, and a portion of the upper electrode layer 64 is electrically connected to the piezoelectric layer 62.

As described above, referring to step g1, the lower electrode layer 61 is formed on the third upper surface 42 of the third substrate 4 by physical or chemical vapor deposition such as sputtering or evaporation, and then the lower electrode is as in step g2. The piezoelectric layer 62 is deposited on the layer 61 by physical or chemical vapor deposition such as sputtering or evaporation. On the lower electrode layer 61, or by a sol-gel process, a piezoelectric layer 62 is deposited on the lower electrode layer 61, and the two are electrically connected through the contact region, and the piezoelectric layer is further connected. The area of 62 is smaller than the area of the lower electrode layer 61, so that the piezoelectric layer 62 cannot completely shield the lower electrode layer 61; the step g3 is further performed, and the partial region of the piezoelectric layer 62 and the lower electrode layer 61 are not shielded by the piezoelectric layer 62. The region is formed by deposition of physical or chemical vapor deposition such as sputtering, evaporation, or the like; finally, step g4 is performed, and sputtering is performed on the insulating layer 63 and another portion of the piezoelectric layer 62 where the insulating layer 63 is not deposited. The upper electrode layer 64 is formed by physical or chemical vapor deposition such as vapor deposition, and the upper electrode layer 64 is electrically connected to the piezoelectric layer 62. The insulating layer 63 is blocked between the upper electrode 64 and the lower electrode layer 61 to avoid two. The short circuit is electrically connected to form a short circuit. The lower electrode layer 61 and the upper electrode 64 can extend the conductive pins (not shown) through the fine pitch bonding wire package technology to receive the external driving signal and the driving voltage.

The first substrate 1, the second substrate 2, and the third substrate 4 may be substrates of the same material. In this embodiment, all of the three substrates are formed by a long crystal process, and the crystal growth process can be performed. The polycrystalline germanium growth control technique means that the first substrate 1, the second substrate 2, and the third substrate 4 are all polycrystalline germanium wafers, and the first thickness after the first substrate 1 is thinned is larger than the thinned third substrate 4 The thickness is three, and the third thickness after the third substrate 4 is thinned is larger than the second thickness after the two substrates 2 are thinned.

The first thickness is between 150 and 200 microns, the second thickness is between 2 and 5 microns, and the third thickness is between 10 and 20 microns.

In addition, the thickness of the foregoing first oxide layer 3 will be greater than the thickness of the second oxide layer 5. In the embodiment, the thickness of the first oxide layer 3 is between 10 and 20 micrometers, and the thickness of the second oxide layer 5 is The first oxide layer 3 and the second oxide layer 5 may be a film of the same material, and the first oxide layer 3 and the second oxide layer 5 may be a cerium oxide (SiO ₂ ) film. It can be produced by sputtering, high temperature oxidation, and the like.

Referring to FIG. 2, a schematic cross-sectional view of the microelectromechanical pump 100 manufactured by the manufacturing method of the present invention, the microelectromechanical pump 100 is provided with a first substrate 1 provided with a first oxide layer 3, and a second The second substrate 2 and the third substrate 4 of the oxide layer 5 are combined in a stacked manner. In the embodiment, the number of the air inlet holes 11 on the first substrate 1 is two, but not limited thereto, and two air inlet holes are provided. 11 is a tapered shape which is tapered. When combined with the second substrate 2, the first oxide layer 3 is connected to the second lower surface 23 of the second substrate 2, and the position of the intake runner 31 of the first oxide layer 3 is And the number of the intake holes 11 of the first substrate 1 correspond to each other. Therefore, in the present embodiment, the intake flow passages 31 are also two, and one end of the two intake flow passages 31 are respectively connected with two intake holes. 11. The other ends of the two intake runners 31 are in communication with the confluence chamber 32, and the gases are respectively passed through the two intake holes 11 to pass through the corresponding intake runners 31 and to the confluence chamber 32. Gathering, the perforations 21 of the second substrate 2 communicate with the confluence chamber 32 for gas passage, and when the third substrate 4 is coupled to the second substrate 2, the third substrate 4 The third lower surface 43 is adjacent to the second oxide layer 5, and the gas chambers 51 of the second oxide layer 5 are respectively in communication with the through holes 21 of the second substrate 2 and the gas passages 41 of the third substrate 4, so that the gas can be perforated 21 After entering the gas chamber 51, it is discharged by the gas passage 41.

As described above, the number of the gas passages 41 of the third substrate 4 is two, but not limited thereto, the gas passage 41 divides the third substrate 4 into three parts, which are the vibrating portions 44 located in the middle of the gas passage 41, respectively. An outer peripheral portion 45 located at the periphery of the gas passage 41, and a connecting portion 46 between the gas passages 41 and for elastically connecting the vibrating portion 44 and the outer peripheral portion 45, wherein the region of the vibrating portion 44 and the gas of the second oxide layer 5 The chamber 51 corresponds to each other, and the piezoelectric assembly 6 is located in the region of the vibrating portion 44. When the piezoelectric assembly 6 is caused to vibrate and displace the vibrating portion 44, the volume of the gas chamber 51 is compressed or expanded to generate an air flow.

In addition, the outer edge region of the through hole 21 of the second substrate 2 is a resonance portion 24, and the periphery of the resonance portion 24 is a fixing portion 25, the resonance portion 24 and the confluence chamber 32 of the first oxide layer 3 and the second oxide layer. The gas chambers 51 of 5 correspond to each other, and the resonance portion 24 can be vibrated and displaced between the manifold chamber 32 and the gas chamber 51.

Please refer to FIG. 2 and FIG. 4A to FIG. 4C. FIG. 4A to FIG. 4C are diagrams showing the operation of the microelectromechanical pump manufactured by the manufacturing method of the present invention; please refer to FIG. 4A for the pressure. The lower electrode layer 61 and the upper electrode 64 of the electrical component 6 receive the externally transmitted driving voltage and driving signal (not shown), and then conduct the same to the piezoelectric layer 62. At this time, the piezoelectric layer 62 receives the driving voltage and After the driving signal, the deformation starts to be deformed due to the influence of the piezoelectric effect, and the amount of change and frequency of the deformation is controlled by the driving voltage and the driving signal, and the piezoelectric layer 62 starts to be deformed by the driving voltage and the driving signal, and then the driving is started. The vibrating portion 44 of the three substrates 4 starts to be displaced, and the piezoelectric assembly 6 drives the vibrating portion 44 to vibrate toward a first direction to pull apart the distance from the second oxide layer 5, wherein the first direction is the vibrating portion 44 toward Away away from the vibration direction of the second oxide layer 5, the volume of the gas chamber 51 of the second oxide layer 5 is increased, and a negative pressure is formed in the gas chamber 51, so that the gas outside the MEMS pump 100 can be sucked by the air inlet hole. 11 enters it and introduces the first oxidation The gas in the confluence chamber 32 of 3 is sucked therein; further, as shown in FIG. 4B, when the vibrating portion 44 is displaced by the piezoelectric assembly 6, the resonance portion 24 of the second substrate 2 is affected by the resonance principle. Displacement toward the first direction, and when the resonance portion 24 is displaced toward the first direction, the space of the gas chamber 51 is compressed, and the gas in the gas chamber 51 is pushed to move toward the gas passage 41 of the third substrate 4, allowing the gas to When the gas passage 41 is discharged, and when the resonance portion 24 is displaced in the first direction to compress the gas chamber 51, the volume of the confluence chamber 32 is lifted by the displacement of the resonance portion 24, and a negative pressure is formed therein to continuously absorb the micro-flow. The air outside the electromechanical pump 100 enters through the air inlet 11; finally, as shown in Fig. 4C, the piezoelectric group The member 6 drives the vibrating portion 44 of the third substrate 4 to vibrate toward a second direction, wherein the second direction is the vibrating portion 44 toward the vibrating direction of the second oxide layer 5, and the first direction is opposite to the second direction. In both directions, the resonance portion 24 of the second substrate 2 is also displaced by the vibration portion 44 toward the second direction, and the gas that synchronously compresses the confluence chamber 32 moves toward the gas chamber 51 through the through hole 21 thereof, and the micro-electromechanical device The gas outside the pump 100 is temporarily entered by the air inlet hole 11, and the gas of the gas chamber 51 is pushed into the gas passage 41 of the third substrate 4, so that the gas of the gas passage 41 is discharged outside the microelectromechanical pump 100, and the subsequent piezoelectric When the assembly 6 is resumed to drive the vibrating portion 44 to be displaced in the first direction, the volume of the gas chamber 51 is greatly increased, and thus a higher drawing force is taken into the gas chamber 51 (as shown in FIG. 4A). By repeating the operation of FIG. 4A to FIG. 4C, the piezoelectric component 6 can continuously drive the vibration displacement of the vibrating portion 44, and the vibration of the resonant portion 24 can be synchronously shifted to change the internal pressure of the microelectromechanical pump 100 to continuously Drilling and exhausting gas MEMS pump 100, the gas transfer operation.

In summary, the present invention provides a manufacturing method of a microelectromechanical pump, which mainly completes the structure of the microelectromechanical pump by a semiconductor process, so as to further reduce the volume of the pump, making it lighter, thinner and shorter, reaching a micron size. The problem of reducing the volume of the previous pump is too large to meet the limitation of the micron size, and it is of great industrial value, and the application is made according to law.

This case has been modified by people who are familiar with the technology, but it is not intended to be protected by the scope of the patent application.

Claims (13)

A manufacturing method of a microelectromechanical pump includes the following steps: (a) providing a first substrate, thinning the first substrate to a first thickness; (b) forming a first oxide layer on the first substrate, And the first substrate etches at least one air inlet hole; (c) providing a second substrate, the second substrate is thinned to a second thickness; (d) forming a second oxide layer on the second substrate, And etching a through hole on the second substrate; (e) bonding the second substrate to the first substrate, and the first oxide layer is located between the first substrate and the second substrate, the air inlet hole Disposing the perforation; (f) providing a third substrate, thinning the third substrate to a third thickness, and etching a plurality of gas channels on the third substrate; (g) disposing a third substrate a piezoelectric component; (h) bonding the third substrate to the second substrate, and the second oxide layer is located between the second substrate and the third substrate, the gas channel being misaligned with the through hole. The method of manufacturing a microelectromechanical pump according to the first aspect of the invention, wherein the step (b) further comprises etching the at least one inlet flow channel and the confluence chamber in the first oxide layer, the inlet flow channel One end of the inlet is in communication with the manifold, and the other end of the inlet passage is in communication with the inlet. The method of manufacturing a microelectromechanical pump according to claim 1, wherein the step (d) further comprises etching a gas chamber in the second oxide layer. The method for manufacturing a microelectromechanical pump according to claim 1, wherein the step (g) comprises the steps of: (g1) depositing an electrode layer; (g2) depositing a piezoelectric layer on the lower electrode layer; (g3) depositing an insulating layer on a portion of the piezoelectric layer and a portion of the lower electrode layer; and (g4) depositing an upper electrode layer on a region where the insulating layer is not deposited on the piezoelectric layer, the upper electrode layer and The piezoelectric layer is electrically connected. The method of manufacturing a microelectromechanical pump according to claim 4, wherein the step (g) is performed by a physical vapor deposition process. The method of manufacturing a microelectromechanical pump according to claim 4, wherein the step (g) is performed by a chemical vapor deposition process. The method for manufacturing a microelectromechanical pump according to the fourth aspect of the invention, wherein the step (g2) is deposited by a sol-gel process. A method of fabricating a microelectromechanical pump as shown in claim 1, wherein the inlet hole of the first substrate is tapered by etching. The method of manufacturing a microelectromechanical pump according to the first aspect of the invention, wherein the first substrate, the second substrate, and the third substrate are each thinned to the first thickness and the second thickness by a polishing process. And the third thickness. The method of fabricating a microelectromechanical pump according to claim 1, wherein the first thickness is greater than the third thickness, and the third thickness is greater than the second thickness. The method of fabricating a microelectromechanical pump according to claim 1, wherein the first oxide layer has a thickness greater than a thickness of the second oxide layer. The method of fabricating a microelectromechanical pump according to claim 1, wherein the first substrate, the second substrate, and the third substrate are one of the germanium wafers formed by a long crystal process. The method of fabricating a microelectromechanical pump according to claim 12, wherein the crystal growth process is a polycrystalline germanium growth control technique.