TWI657040B - 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 and etching at least one air inlet hole in the first substrate; (b) providing a second substrate Thinning the second substrate to a second thickness, providing a first first oxide layer and a second oxide layer on the second substrate, and etching the via holes on the second substrate; (c) bonding the second substrate to the first substrate a substrate, wherein the first oxide layer is located between the first substrate and the second substrate, the air inlet hole and the through hole are misaligned; (d) providing a third substrate, thinning the third substrate to a third thickness and etching at least one gas channel (e) disposing a piezoelectric component on the third substrate; (f) and 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 passage and the perforation being misaligned.

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, electronic heat dissipation, etc., even the most popular wearable devices can be seen in the past. The pump has gradually become the trend toward miniaturization of the device 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, thinning the first substrate to a first thickness, and The first substrate etches at least one air inlet hole; (b) provides a second substrate, the second substrate is thinned to a second thickness, and the second substrate is provided with a first oxide layer and a second substrate An oxide layer is formed on the second substrate; (c) the second substrate is bonded 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; (d) providing a third substrate, thinning the third substrate to a third thickness and etching at least one gas passage; (e) disposing a piezoelectric component on the third substrate And (f) 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.

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~f‧‧‧Steps in the manufacturing method of MEMS pump

E1~e4‧‧‧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 view of the microelectromechanical pump profile of the present 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 is to be understood that the present invention is capable of various modifications in various embodiments, and is not intended to limit the scope of the invention.

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 view of the manufacturing process of the MEMS pump 100. The process of manufacturing the MEMS pump 100 is as follows: Step a, providing a first substrate 1 , thinning the first substrate 1 to a first thickness and etching at least the first substrate 1 An air inlet hole 11; step b, providing a second substrate 2, thinning the second substrate 2 to a second thickness, and providing a first oxide layer 3 and a second oxide layer 5 on the second substrate 2 And etching a through hole on the second substrate 2; in step c, the second substrate 2 is bonded to the first substrate 1, and the first oxide layer 3 is located on the first substrate 1 and the second substrate 2 The air inlet hole 11 is offset from the through hole 21; in step d, 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; step e, The third substrate 4 is provided with a piezoelectric component 6; and step f is used to bond the third substrate 4 to the second substrate 2, The second oxide layer 5 is located between the second substrate 2 and the third substrate 4, the gas passage 41 and the through-hole 21 offset.

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, cutting, or the like, and the first substrate 1 is thin. After the first thickness, the first upper surface 12 and the first lower surface 13 are formed, and then the first lower surface 13 of the first substrate 1 is formed by at least one air inlet 11 by dry etching or wet etching. 11 will penetrate the first upper surface 12 and the first lower surface 13 of the first substrate 1, and the aperture of the air inlet hole 11 may be tapered from the first lower surface 13 to the first upper surface 12.

As shown in step b, the 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. The second upper surface 22 and the second lower surface 23 are further formed on the second lower surface 23 of the second substrate 2 The oxide layer 3 and the second upper surface 22 form a second oxide layer 5, and a through hole 21 is formed in the center of the second substrate 2 by using an etching process. The through hole 21 penetrates the second upper surface 22 and the second lower surface of the second substrate 2. In addition, the step b further includes forming at least one of the inlet flow path 31 and the confluence chamber 32 by using an etching process on the first oxide layer 3, and the inlet flow path 31 and the confluence chamber 32 communicate with each other, and In step b, it is further included that a central portion of the second oxide layer 5 is formed into a gas chamber 51 using an etching process.

Further, as shown in step c, the second substrate 2 is bonded to the first substrate 1, and the first oxide layer 3 of the second lower surface 23 of the second substrate 2 is bonded to 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, and at this time, the through holes 21 on the second substrate 2 are offset from the air inlet holes 11 of the first substrate 1; wherein, the first oxidation is performed. The intake passage 31 of the 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. One end of the intake passage 31 is connected to the intake hole 13 and communicates with the intake hole 11 The other end of the air flow path 31 communicates with the confluence chamber 32 to allow gas to enter the intake hole 11 of the first substrate 1, respectively, and then converge through the corresponding intake flow path 31 in the confluence chamber 32.

As shown in step d, a third substrate 4 is provided, and the third substrate 4 is also thinned to a third thickness by grinding, etching or cutting, etc., so that the third substrate 4 has a third upper surface 42 and a first Three lower surfaces 43 are formed on 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 vibrating portion 44 and an outer circumference. The portion 45 and the three portions of the plurality of connecting portions 46 (shown in FIG. 5) are respectively the vibrating portion 44 surrounded by the gas passage 41, the outer peripheral portion 45 surrounding the periphery of the gas passage 41, and the respective gas passages 41. A plurality of connecting portions 46 are 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. Referring to the step e, a piezoelectric assembly 6 is formed on the third upper surface 41 of the third substrate 4.

Finally, as shown in step (f), the third lower surface 43 of the third substrate 4 is bonded to the second oxide layer 5 of the second upper surface 22 of the second substrate 2, so that the second oxide layer 5 is located at the second Between the substrate 2 and the third substrate 4, and the perforations 21 of the second substrate 2 and the gas passages 41 of the third substrate 4 are dislocated, wherein the perforations 21 of the second substrate 2 and the gas chamber of the second oxide layer 5 The 51 is in communication with each other, and the gas passage 41 of the third substrate 4 and the gas chamber 51 communicate 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 e is as follows: step e1, depositing the electrode layer 61; step e2, under A piezoelectric layer 62 is deposited on the electrode layer 61; in step e3, 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 e4, 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 e1, 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 e2. The piezoelectric layer 62 is also deposited on the layer 61 by physical or chemical vapor deposition such as sputtering, evaporation or the like on the lower electrode layer 61, or the piezoelectric layer 62 is deposited by a sol-gel process. Formed on the lower electrode layer 61, and the regions through which the two are in contact are electrically connected, and the area of the piezoelectric layer 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; In step e3, the insulating layer 63 is deposited in a partial region of the piezoelectric layer 62 and a region where the lower electrode layer 61 is not shielded by the piezoelectric layer 62 by physical or chemical vapor deposition such as sputtering or evaporation; finally, step e4 is performed. The upper electrode layer 64 is formed on the insulating layer 63 and another portion of the piezoelectric layer 62 where the insulating layer 63 is not deposited by physical or chemical vapor deposition such as sputtering or evaporation, and the upper electrode layer 64 and the piezoelectric layer are formed. 62 is electrically connected, and is blocked by the upper layer 64 through the insulating layer 63. Between the electrode layers 61, electrically connected to both avoid yield A short circuit occurs, wherein the lower electrode layer 61 and the upper electrode 64 can extend the conductive pins (not shown) through the fine pitch wire bonding technology for receiving the external driving signals 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 (SiO2) film. It is produced by sputtering, high temperature oxidation, and the like.

Referring to FIG. 2, the microelectromechanical pump 100 is combined by the first substrate 1, the second substrate 2 provided with the first oxide layer 3 and the second oxide layer 5, and the third substrate 4 in a stacked manner. In the embodiment, the number of the air inlet holes 11 on the first substrate 1 is two, and the two air inlet holes 11 are tapered to form a tapered shape. When combined with the second substrate 2, on the second substrate 2 The first oxide layer 3 of the second lower surface 23 is connected to the first substrate 1, and the position and the number of the inlet runners 31 of the first oxide layer 3 correspond to the inlet holes 11 of the first substrate 1, thereby In the present embodiment, the intake flow passages 31 are also two, and one end of the two intake flow passages 31 is connected to the two intake holes 11, respectively, and the other end of the two intake flow passages 31 is connected to the confluence. The chamber 32 allows the gas to enter the two intake holes 11 respectively, and then passes through the corresponding intake passage 31 and accumulates in the confluence chamber 32, and The perforations 21 of the two substrates 2 communicate with the confluence chamber 32 for gas passage, and when the third substrate 4 is bonded to the second substrate 2, adjacent to the second oxide layer 5 of the second upper surface 22 of the second substrate 2. The gas chambers 51 of the second oxide layer 5 are respectively in communication with the perforations 21 of the second substrate 2 and the gas passages 41 of the third substrate 4, so that the gas can enter the gas chamber 51 through the perforations 21 and then be discharged by the gas passages 41. .

As described above, the gas passage 41 of the third substrate 4 divides the third substrate 4 into three parts, which are the vibrating portion 44 located at the center of the gas passage 41, the outer peripheral portion 45 around the gas passage 41, and the gas passage 41. And a connecting portion 46 for elastically connecting the vibrating portion 44 and the outer peripheral portion 45, wherein the region of the vibrating portion 44 corresponds to the gas chamber 51 of the second oxide layer 5, and the piezoelectric component 6 is located at the vibrating portion 44 In the region, 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 peripheral 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 5 The gas chambers 51 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 is started 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 third is driven. The vibrating portion 44 of the substrate 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 facing away from Vibration of the second oxide layer 5 In the direction, 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 is sucked into the gas inlet hole 11 and introduced therein. In the confluence chamber 32 of the first oxide layer 3, please continue to refer to FIG. 4B. When the vibrating portion 44 is displaced by the piezoelectric assembly 6, the resonance portion 24 of the second substrate 2 may be affected by the resonance principle. When displaced in the first direction and 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, so that the gas can Discharged through the gas passage 41, and when the resonance portion 24 is displaced toward the first direction to compress the gas chamber 51, the volume of the confluence chamber 32 is increased by the displacement of the resonance portion 24, and a negative pressure is formed therein to continuously absorb The air outside the MEMS pump 100 enters the air through the air inlet 11; finally, as shown in FIG. 4C, the piezoelectric component 6 drives the vibration portion 44 of the third substrate 4 to vibrate toward a second direction, wherein the second direction Approaching the vibrating portion 44 The vibration direction of the dioxide layer 5, and the first direction and the second direction are opposite directions, whereby the resonance portion 24 of the second substrate 2 is also displaced by the vibration portion 44 toward the second direction, and the synchronous compression confluence The gas in the chamber 32 moves through the perforations 21 toward the gas chamber 51, and the gas outside the microelectromechanical pump 100 is temporarily suspended by the intake holes 11, and the gas in the gas chamber 51 is pushed to the gas passage of the third substrate 4. 41, the gas of the gas passage 41 is discharged outside the microelectromechanical pump 100, and when the subsequent piezoelectric assembly 6 resumes to move the vibrating portion 44 toward the first direction, the volume of the gas chamber 51 is greatly increased, thereby being higher. The drawing force draws the gas into the gas chamber 51 (as shown in FIG. 4A), and repeats the operation operations of FIG. 4A to FIG. 4C, so that the vibration component 44 can be continuously driven and transmitted through the piezoelectric component 6 and synchronously linked. The resonance portion 24 vibrates and shifts to change the internal pressure of the microelectromechanical pump 100, so that the gas is continuously extracted and exhausted to complete the gas transmission operation of the microelectromechanical pump 100.

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, thereby further reducing the volume of the pump to make it more thin and light. Short, reaching the size of the micron level, reducing the problem that the previous pump volume is too large to reach the micrometer size limit, and it is of great industrial value.

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 steps of: (a) providing a first substrate, thinning the first substrate to a first thickness, and etching, by the first substrate, at least one air inlet hole; (b Providing a second substrate, thinning the second substrate to a second thickness, forming a first oxide layer and a second oxide layer on the second substrate, and etching a second substrate (c) 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 is misaligned with the through hole; (d) providing a a third substrate, the third substrate is thinned to a third thickness and a plurality of gas channels are etched; (e) a piezoelectric component is disposed on the third substrate; and (f) the third substrate is bonded to the third substrate a second substrate, and the second oxide layer is located between the second substrate and the third substrate, and the gas channel is 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 Connected between the confluence chamber and the air inlet aperture. The method of fabricating a microelectromechanical pump according to claim 1, wherein the step (b) 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 (e) comprises the steps of: (e1) depositing an electrode layer; and (e2) depositing a piezoelectric layer on the lower electrode layer; (e3) depositing an insulating layer on a portion of the piezoelectric layer and a portion of the lower electrode; and (e4) depositing an upper electrode layer on the region where the insulating layer is not deposited on the piezoelectric layer, and the upper electrode layer is electrically connected to the piezoelectric layer. The method for manufacturing a microelectromechanical pump according to claim 4, wherein the step (e1) is performed by a physical vapor deposition process. The method for manufacturing a microelectromechanical pump according to claim 4, wherein the step (e1) is performed by a chemical vapor deposition process. The method for manufacturing a microelectromechanical pump according to claim 4, wherein the step (e2) is performed by a sol-gel process. The manufacturing method of the microelectromechanical pump shown in claim 1, wherein the pores of the gas inlet hole of the first substrate are tapered by an isotropic 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.