TWI839913B - Method for manufacturing micro fluid pump - Google Patents

Abstract

A method for manufacturing micro fluid pump is disclose and includes steps of: providing a first substrate; etching an upper surface of the first substrate to form at least one first groove; etching the upper surface of the first substrate to form a second groove, and the first groove is located under the bottom of the second groove; depositing a first binding layer on the surfaces of the at least one first groove and the second groove; providing a third substrate; depositing a second binding layer on the surface of the third substrate; patterned etching the second binding layer; and providing a second substrate and binding the second substrate with the patterned-etched second binding layer of the third substrate.

Description

Manufacturing method of micro fluid pump

This case is about a method for manufacturing a microfluid pump, especially a method for manufacturing a microfluid pump through a semiconductor process.

With the rapid development of technology, the application of fluid transport devices is becoming more and more diversified, including industrial applications, biomedical applications, healthcare, electronic heat dissipation, etc., and even the popular wearable devices can be seen. It can be seen that traditional pumps have gradually tended towards miniaturization of devices and maximum flow rate, and MEMS pumps can greatly reduce the size of fluid transport devices. Therefore, MEMS pumps are obviously the main development direction of miniaturized fluid transport devices at present.

Please refer to FIG. 5 , which shows a prior art microfluidic pump 90 , including a first substrate 901 , a first bonding layer 902 , a second substrate 903 and a piezoelectric component 904 . The first substrate 901 is a silicon substrate having a plurality of first fluid channels 9011, which are conical in shape; the first connecting layer 902 is silicon oxide, defines a second fluid channel 9021, and is stacked on the first substrate 901; the second substrate 903 is stacked on the first connecting layer 902, and includes a silicon structure layer 9031, a second connecting layer 9035, and a silicon thinning layer 9037 stacked in order from bottom to top; the silicon structure layer 9031 has a through hole 9032, a vibration portion 9033, and a fixing portion 9034; the second connecting layer 9035 is silicon oxide. , having a resonance chamber 9036; the silicon thin layer 9037 has an actuating portion 9038, a peripheral portion 9039, a connecting portion 903A and a third fluid channel 903B, wherein the peripheral portion 9039 of the outer ring of the actuating portion 9038 is connected to the connecting portion 903A and has a third fluid channel 903B; the piezoelectric component 904 is stacked on the actuating portion 9038 of the silicon thin layer 9037, and the piezoelectric component 904 includes a lower electrode layer 9041, a piezoelectric layer 9042, an insulating layer 9043 and an upper electrode layer 9044 stacked in sequence above the actuating portion 9038.

In the prior art, the taper wet etching angle of the first fluid channel 9011 is too large due to the crystal orientation of the wafer, and the aspect ratio is too high when dry etching is used. The process is difficult and the flow resistance is large. Furthermore, the second fluid channel 9021 defined by the first bonding layer 902 must be thick enough, but it is not easy to generate thicker silicon oxide, and there will be obvious stress problems, which makes it easier to peel when bonding with the second substrate 903.

The main purpose of this case is to provide a method for manufacturing micro-electromechanical pumps, using semiconductor processes to manufacture micron-scale micro-electromechanical pumps, so as to improve the process yield and fluid transport efficiency of the structure.

To achieve the above-mentioned purpose, the general implementation of the present invention is to provide a method for manufacturing a microfluidic pump, comprising: step 1. preparing a first substrate; step 2. etching an upper surface of the first substrate to form at least one first groove; step 3. etching the upper surface of the first substrate to form a second groove, wherein the at least one first groove is located at the bottom of the second groove; step 4. depositing a first bonding layer on the surface of the at least one first groove and the second groove of the first substrate; step 5. preparing a third substrate; step 6. depositing a second bonding layer on the surface of the third substrate; step 7. pattern etching the second bonding layer; step 8. preparing a second substrate, bonding the second substrate and the patterned second bonding layer of the third substrate to each other; The layers are bonded to each other; step 9. removing a portion of the second substrate; step 10. patterning and etching the second substrate; step 11. bonding the surface of the first substrate having the at least one first groove and the second groove to the second substrate; step 12. removing a portion of the third substrate; step 13. sequentially depositing a lower electrode layer and a piezoelectric layer on the third substrate; step 1 4. Patterning the lower electrode layer and the piezoelectric layer; Step 15. Depositing an insulating layer and patterning the insulating layer; Step 16. Depositing an upper electrode layer and patterning the upper electrode layer; Step 17. Patterning the insulating layer and the third substrate; Step 18. Patterning the lower surface of the first substrate; Step 19. Etching the first connecting layer.

10, 20, 30: Micro fluid pump

101, 201, 301: first substrate

1011, 2011, 3011: Fluid channel

101A, 201A, 301A: First groove

101B, 201B, 301B: Second groove

1012, 2012, 3012: first fluid channel

102, 202, 302: First layer

103, 203, 303: Second substrate

1031, 2031, 3031: Perforation

1032, 2032, 3032: Vibration part

1033, 2033, 3033: Fixed part

104, 204, 304: Second fluid channel

105, 205, 305: Second layer

3051: Lower level

3052: Polycrystalline silicon layer

3053: Upper level

106, 206, 306: Third substrate

1061, 2061, 3061: Resonance chamber

1062, 2062, 3062: Third fluid channel

1063, 2063, 3063: Actuator

1064, 2064, 3064: Connection part

1065, 2065, 3065: Periphery

107, 207, 307: Piezoelectric components

1071, 2071, 3071: lower electrode layer

1072, 2072, 3072: piezoelectric layer

1073, 2073, 3073: Insulation layer

1074, 2074, 3074: upper electrode layer

90: Micro fluid pump

901: First substrate

9011: First fluid channel

902: First layer

9021: Second fluid channel

903: Second substrate

9031: Silicon structural layer

9032:Piercing

9033: Vibration Department

9034:Fixed part

9035: Second layer

9036:Resonance Chamber

9037:Silicon thinning layer

9038: Actuator

9039: Periphery

903A:Connection part

903B: Third fluid channel

904: Piezoelectric components

9041: Lower electrode layer

9042: Piezoelectric layer

9043: Insulation layer

9044: Upper electrode layer

S1~S19: Steps

Figures 1A to 1C are flow charts of the steps of manufacturing the microfluidic pump of this case.

Figures 2A to 2S are schematic diagrams of the first embodiment of the manufacturing method of the microfluid pump of this case.

Figures 3A to 3T are schematic diagrams of the steps of the second embodiment of the manufacturing method of the microfluidic pump of this case.

Figures 4A to 4S are schematic diagrams of the steps of the third embodiment of the manufacturing method of the microfluid pump of this case.

Figure 5 is a schematic diagram of a microfluid pump in the prior art.

The embodiments that embody the features and advantages of this case will be described in detail in the following description. It should be understood that this case can have various variations in different forms, all of which do not deviate from the scope of this case, and the descriptions and diagrams therein are essentially for illustrative purposes, not for limiting this case.

Please refer to FIG. 2S , which is a first embodiment of the microfluid pump of the present invention. The microfluid pump 10 includes a first substrate 101 , a first connecting layer 102 , a second substrate 103 , a second connecting layer 105 , a third substrate 106 and a piezoelectric component 107 . The first substrate 101 is provided with a fluid groove 1011 and at least one first fluid channel 1012, wherein the fluid groove 1011 is in the shape of a deep groove; the first substrate 101, the first connecting layer 102, and the second substrate 103 are stacked in sequence from bottom to top, and define a second fluid channel 104, the top of the second fluid channel 104 is provided with a through hole 1031, the through hole 1031 is located at the center of the second substrate 103, the outer periphery of the through hole 1031 is surrounded by a vibrating portion 1032, and the vibrating portion 1032 is surrounded by a fixing portion 1033; the second substrate 103, the second connecting layer 105, and the third substrate 106 are stacked in sequence from bottom to top, and define a resonance chamber 1061; the third substrate 106 further includes It includes at least one third fluid channel 1062, an actuating portion 1063, a connecting portion 1064 and a peripheral portion 1065, wherein the peripheral portion 1065 is arranged around the periphery of the actuating portion 1063, and the peripheral portion 1065 is coupled to the actuating portion 1063 through the connecting portion 1064. The third fluid channel 1062 passes through the third substrate 106, so that the third fluid channel 1062 and the resonance chamber 1061 can be connected to the second fluid channel 104, the first fluid channel 1012, and the fluid through slot 1011 in sequence through the through hole 1031; the piezoelectric component 107 is stacked on the actuating portion 1063, and includes a lower electrode layer 1071, a piezoelectric layer 1072, an insulating layer 1073 and an upper electrode layer 1074.

Please refer to Figures 1A to 1C and Figures 2A to 2S. As shown in Figure 2A, step 1. prepare a first substrate 101. It is worth noting that the first substrate 101 is a silicon substrate (Si) with a thickness of 270~430μm, but not limited to this.

As shown in FIG. 2B, step 2. Etching an upper surface of the first substrate 101 to form at least one first groove 101A. It is worth noting that this etching method can be physical or chemical etching.

As shown in FIG. 2C, step 3. Etching the upper surface of the first substrate 101 to form a second groove 101B, wherein the first groove 101A is located at the bottom of the second groove 101B. It is worth noting that this etching method can be physical or chemical etching.

As shown in FIG. 2D, step 4. depositing the first bonding layer 102 on the surface of at least one first groove 101A and the second groove 101B of the first substrate 101. It is worth noting that the first bonding layer 102 is formed on the surface of the first substrate 101 by physical vapor deposition or chemical vapor deposition or thermal oxidation. The first bonding layer 102 is silicon oxide with a thickness range of 1~5μm.

As shown in FIG. 2E, step 5. prepare the third substrate 106. It is worth noting that the third substrate 106 can be a silicon on insulator (SOI) wafer, but is not limited thereto.

As shown in FIG. 2F, step 6. depositing the second bonding layer 105 on the surface of the third substrate 106. It is worth noting that the second bonding layer 105 is formed on the surface of the third substrate 106 by physical vapor deposition or chemical vapor deposition or thermal oxidation, and the thickness of the second bonding layer 105 ranges from 1 to 5 μm.

As shown in FIG. 2G, step 7. pattern etching the second connecting layer 105. It is worth noting that after step 7. pattern etching the second connecting layer 105, a resonant chamber 1061 is generated.

As shown in FIG. 2H, step 8. prepare the second substrate 103, and bond the second substrate 103 and the patterned second bonding layer 105 of the third substrate 106 to each other. It is worth noting that the second substrate 103 can be a silicon-on-insulation layer (SOI) wafer, but is not limited thereto.

As shown in Figure 2I, step 9. removes part of the second substrate 103. It is worth noting that the remaining thickness of the second substrate 103 after step 9. removes part of the second substrate 103 is in the range of 1-5μm.

As shown in FIG. 2J, step 10. patterning and etching the second substrate 103. It is worth noting that after step 10. patterning and etching the second substrate 103, the second substrate 103 is divided into a through hole 1031, a vibration portion 1032 and a fixed portion 1033.

As shown in FIG. 2K, step 11. The surface of the first substrate 101 having at least one first groove 101A and a second groove 101B is bonded to the second substrate 103. It is worth noting that the order of bonding the second substrate 103 to the third substrate 106 is prior to bonding the second substrate 103 to the first substrate 101. The order of bonding the substrates is considered to avoid the yield problem of the microfluid pump 10 caused by poor bonding during bonding. Therefore, bonding the second substrate 103 to the third substrate 106 first and then to the first substrate 101 can improve the bonding yield.

As shown in Figure 2L, step 12. removes part of the third substrate 106. It is worth noting that the remaining thickness of the third substrate 106 after the part of the third substrate 106 is removed in step 12. ranges from 5 to 20 μm.

As shown in Figure 2M, step 13. Sequentially deposit the lower electrode layer 1071 and the piezoelectric layer 1072 on the third substrate 106.

As shown in Figure 2N, step 14. Patterning and etching the lower electrode layer 1071 and the piezoelectric layer 1072.

As shown in FIG. 20, step 15. depositing an insulating layer 1073 and patterning and etching the insulating layer 1073.

As shown in FIG. 2P, step 16. depositing the upper electrode layer 1074 and patterning and etching the upper electrode layer 1074.

As shown in FIG. 2Q, step 17. patterning the insulating layer 1073 and the third substrate 106. It is worth noting that after step 17. patterning the insulating layer 1073 and the third substrate 106, at least one third fluid channel 1062 is generated, and the third substrate 106 is divided into an actuating portion 1063 and at least one peripheral portion 1065, wherein at least one connecting portion 1064 connects the actuating portion 1063 and the peripheral portion 1065, and at least one third fluid channel 1062 is also between the actuating portion 1063 and the peripheral portion 1065. In addition, it is worth noting that the lower electrode layer 1071, the piezoelectric layer 1072, the insulating layer 1073 and the upper electrode layer 1074 located on the actuating portion 1063 of the third substrate 106 are the piezoelectric component 107. In addition, it is worth noting that the piezoelectric layer 1072 is circularly disposed above the actuating portion 1063 of the third substrate 106, so that the actuating portion 1063 is also circular.

As shown in FIG. 2R, step 18. patterning and etching the lower surface of the first substrate 101.

As shown in FIG. 2S, step 19. Etch the first bonding layer 102. The production of the microfluid pump 10 is completed.

It is worth noting that the fluid channel 1011 shown in FIG. 2S is segmented etching, which solves the problem of excessive etching angle or high aspect ratio etching in the previous technology, and reduces the flow resistance of the fluid flowing through the first fluid channel 1012. In addition, the first connecting layer 102 is silicon oxide, but the thickness is adjusted to 1~5μm, which can avoid the stress peeling problem caused by bonding with the second substrate 103. In addition, the second fluid channel 104 is defined by etching the first substrate 101.

Furthermore, it is worth noting that the second substrate 103 shown in FIG. 2S is a silicon structure layer, which can be transferred from an SOI chip, and has a thickness of 1 to 5 μm, but is not limited thereto. The thickness of the second substrate 103 can be adjusted according to design requirements. The second substrate 103 is divided into three areas: a through hole 1031, a vibration part 1032, and a fixed part 1033. The through hole 1031 is located at the center, the vibration part 1032 is located at the peripheral area of the through hole 1031, and the fixed part 1033 is located at the peripheral area of the second substrate 103.

In addition, it is worth noting that the second bonding layer 105 shown in FIG. 2S is silicon oxide with a thickness of 1 to 5 μm. The thickness of the first bonding layer 102 can be equal to the thickness of the second bonding layer 105, which can be 1.1 μm, but is not limited thereto. The thickness of the first bonding layer 102 and the thickness of the second bonding layer 105 can also be unequal and can be adjusted according to design requirements. The second bonding layer 105 is stacked on the second substrate 103.

In addition, it is worth noting that the third substrate 106 shown in FIG. 2S is a silicon structure layer, which can be transferred from an SOI chip, and has a thickness of 10~20μm, but is not limited thereto. The thickness of the third substrate 106 can be adjusted according to design requirements; the third substrate 106 is stacked on the second bonding layer 105 to form a resonance chamber 1061; the third substrate 106 has an actuating portion 1063 and a peripheral portion 1065, and the outer ring of the actuating portion 1063 has a third fluid channel 1062 and a connecting portion 1064, and the connecting portion 1064 is used to connect the actuating portion 1063 and the peripheral portion 1065.

It is worth noting that the second substrate 103 and the third substrate 106 can be single crystal silicon, polycrystalline silicon or amorphous silicon. The second substrate 103 and the third substrate 106 can also be made using a deposition or thinning process.

The piezoelectric component 107 further includes a lower electrode layer 1071, a piezoelectric layer 1072, an insulating layer 1073, and an upper electrode layer 1074. The piezoelectric layer 1072 is stacked on the lower electrode layer 1071; the insulating layer 1073 is laid on a portion of the surface of the piezoelectric layer 1072 and a portion of the surface of the lower electrode layer 1071, wherein the insulating layer 1073 is electrically insulating; and the upper electrode layer 1074 is stacked on the insulating layer 1073 and on the remaining surface of the piezoelectric layer 1072 where the insulating layer 1073 is not provided. It is worth noting that the piezoelectric layer 1072 is circularly disposed above the actuating portion 1063 of the third substrate 106, so that the actuating portion 1063 is also circular. In addition, it is worth noting that the diameter of the piezoelectric layer 1072 is 140~500μm, but it is not limited to this. The diameter of the piezoelectric layer 1072 can be adjusted according to the overall size of the microfluidic pump 10. In addition, it is worth noting that the diameter ratio of the piezoelectric layer 1072 to the actuating portion 1063 ranges from 1:1.3 to 1:3.6. In other words, the size of the piezoelectric layer 1072 is smaller than the size of the actuating portion 1063.

Through the actuation of the piezoelectric component 107, the actuator 1063 also vibrates up and down, and the vibrating portion 1032 of the second substrate 103 vibrates in different phases, so that the resonance chamber 1061 forms a negative pressure, and the fluid passes through the first fluid channel 1012 from the fluid groove 1011, and then passes through the second fluid channel 104, and continues to flow through the resonance chamber 1061 through the through hole 1031 of the second substrate 103, and finally passes through the third fluid channel 1062 of the third substrate 106 to complete the fluid delivery. It is worth noting that the actuation frequency of the actuator 1063 is in the high frequency range of 0.1~1.5MHz, so that the microfluid can accumulate a small amount to generate more flow, but it is not limited to this. The actuation frequency of the actuator 1063 can be adjusted by the design of the overall microfluid pump 10. In addition, it is worth noting that the actuator 1063 is circular and has a diameter of 400-550 μm, but is not limited thereto. The shape and size of the actuator 1063 can also be adjusted by the design of the overall microfluidic pump 10.

The operating voltage of the microfluid pump 10 is 2~12V. It is worth mentioning that the operating voltage of the microfluid pump 10, the operating frequency of the actuator 1063 of the third substrate 106, the thickness of the third substrate 106 and the resonance of the vibration part 1032 of the second substrate 103 will all affect the delivery volume and efficiency of the fluid.

Please refer to FIG. 3T, which is a second embodiment of the microfluid pump of the present invention. The main difference from the first embodiment is that the third substrate 206 is etched to a depth. In this embodiment, the microfluid pump 20 comprises a first substrate 201, a first connecting layer 202, a second substrate 203, a second connecting layer 205, a third substrate 206 and a piezoelectric component 207. The first substrate 201 is provided with a fluid through groove 2011 and at least one first fluid channel 2012, wherein the fluid through groove 2011 is a deep groove; the first substrate 201, the first connecting layer 202 and the second substrate 203 are stacked from bottom to top in sequence and define a second fluid channel 204. The second fluid channel 204 is provided with a through hole 2031 at the top. The through hole 2031 is located at the center of the second substrate 203. The outer periphery of the through hole 2031 is surrounded by a vibrating portion 2032, and the vibrating portion 2032 is surrounded by a fixing portion 2033; the second substrate 203, the second connecting layer 205 and the third substrate 2 06 are stacked from bottom to top, and define a resonance chamber 2061; the third substrate 206 further includes at least one third fluid channel 2062, an actuating portion 2063, a connecting portion 2064 and a peripheral portion 2065, wherein the peripheral portion 2065 is arranged around the periphery of the actuating portion 2063, and the peripheral portion 2065 is coupled to the actuating portion 2063 through the connecting portion 2064, and the third fluid channel 206 2 penetrates the third substrate 206, so that the third fluid channel 2062 and the resonance chamber 2061 can be connected to the second fluid channel 204, the first fluid channel 2012, and the fluid channel 2011 in sequence through the through hole 2031; the piezoelectric component 207 is stacked on the actuator 2063, including a lower electrode layer 2071, a piezoelectric layer 2072, an insulating layer 2073 and an upper electrode layer 2074.

Please refer to Figures 1A to 1C and Figures 3A to 3T. As shown in Figure 3A, step 1. prepare a first substrate 201. It is worth noting that the first substrate 201 is a silicon substrate (Si) with a thickness of 270~430μm, but not limited to this.

As shown in FIG. 3B, step 2. Etching an upper surface of the first substrate 201 to form at least one first groove 201A. It is worth noting that this etching method can be physical or chemical etching.

As shown in FIG. 3C, step 3. Etching the upper surface of the first substrate 201 to form a second groove 201B, wherein the first groove 201A is located at the bottom of the second groove 201B. It is worth noting that this etching method can be physical or chemical etching.

As shown in FIG. 3D, step 4. depositing a first bonding layer 202 on the surface of at least one first groove 201A and a second groove 201B of the first substrate 201. It is worth noting that the first bonding layer 202 is formed on the surface of the first substrate 201 by physical vapor deposition or chemical vapor deposition or thermal oxidation. The first bonding layer 202 is silicon oxide with a thickness ranging from 1 to 5 μm.

As shown in FIG. 3E, step 5. prepare the third substrate 206. It is worth noting that the third substrate 206 can be a silicon-on-insulation layer (SOI) wafer, but is not limited thereto.

As shown in FIG. 3F, step 6. depositing the second bonding layer 205 on the surface of the third substrate 206. It is worth noting that the second bonding layer 205 is formed on the surface of the third substrate 206 by physical vapor deposition or chemical vapor deposition or thermal oxidation, and the thickness of the second bonding layer 205 ranges from 1 to 5 μm.

As shown in FIG. 3G, step 7. pattern etching the second connecting layer 205. It is worth noting that after step 7. pattern etching the second connecting layer 205, a resonant chamber 2061 is generated.

As shown in FIG. 3H, after step 7. patterning and etching the second connecting layer 205, the third substrate 206 is further etched to a depth. It is worth noting that etching the third substrate 206 to a depth increases the space of the resonance chamber 2061 shown in FIG. 3T, appropriately reduces the squeeze film damping, and when the piezoelectric component 207 is actuated to drive the actuating portion 2063 of the third substrate 206 to vibrate, it is less likely to produce a stiction effect with the vibrating portion 2032 of the second substrate 203.

As shown in FIG. 3I, step 8. prepare the second substrate 203, and bond the second substrate 203 and the patterned second bonding layer 205 of the third substrate 206 to each other. It is worth noting that the second substrate 203 can be a silicon-on-insulation layer (SOI) wafer, but is not limited thereto.

As shown in Figure 3J, step 9. removes part of the second substrate 203. It is worth noting that the remaining thickness of the second substrate 203 after step 9. removes part of the second substrate 203 is in the range of 1-5μm.

As shown in FIG. 3K, step 10. patterning the second substrate 203. It is worth noting that after step 10. patterning the second substrate 203, the second substrate 203 is divided into a through hole 2031, a vibration portion 2032 and a fixed portion 2033.

As shown in FIG. 3L, step 11. The surface of the first substrate 201 having at least one first groove 201A and a second groove 201B is bonded to the second substrate 203. It is worth noting that the order of bonding the second substrate 203 to the third substrate 206 is prior to bonding the second substrate 203 to the first substrate 201. The order of bonding the substrates is considered to avoid the yield problem of the microfluid pump 20 caused by poor bonding during bonding. Therefore, bonding the second substrate 203 to the third substrate 206 first and then to the first substrate 201 can improve the bonding yield.

As shown in FIG. 3M, step 12. removes part of the third substrate 206. It is worth noting that the remaining thickness of the third substrate 206 after the part of the third substrate 206 is removed in step 12. ranges from 5 to 20 μm.

As shown in Figure 3N, step 13. Sequentially deposit the lower electrode layer 2071 and the piezoelectric layer 2072 on the third substrate 206.

As shown in FIG. 30, step 14. Patterning and etching the lower electrode layer 2071 and the piezoelectric layer 2072.

As shown in Figure 3P, step 15. Deposit the insulating layer 2073 and pattern-etch the insulating layer 2073.

As shown in FIG. 3Q, step 16. depositing the upper electrode layer 2074 and patterning and etching the upper electrode layer 2074.

As shown in FIG. 3R, step 17. patterning the insulating layer 2073 and the third substrate 206. It is worth noting that after step 17. patterning the insulating layer 2073 and the third substrate 206, at least one third fluid channel 2062 is generated, and the third substrate 206 is divided into an actuating portion 2063 and at least one peripheral portion 2065, wherein at least one connecting portion 2064 connects the actuating portion 2063 and the peripheral portion 2065, and at least one third fluid channel 2062 is also between the actuating portion 2063 and the peripheral portion 2065. In addition, it is worth noting that the lower electrode layer 2071, the piezoelectric layer 2072, the insulating layer 2073 and the upper electrode layer 2074 located on the actuating portion 2063 of the third substrate 206 are the piezoelectric component 207. In addition, it is worth noting that the piezoelectric layer 2072 is circularly disposed above the actuating portion 2063 of the third substrate 206, so that the actuating portion 2063 is also circular.

As shown in FIG. 3S, step 18. patterning and etching the lower surface of the first substrate 201.

As shown in Figure 3T, step 19. Etch the first bonding layer 202. The production of the microfluidic pump 20 is completed.

It is worth noting that the fluid channel 2011 shown in Figure 3T is segmented etching, which solves the problem of excessive etching angle or high aspect ratio etching in the previous technology, and reduces the flow resistance of the fluid flowing through the first fluid channel 2012. In addition, the first connecting layer 202 is silicon oxide, but the thickness is adjusted to 1~5μm, which can avoid the stress peeling problem caused by bonding with the second substrate 203. In addition, the second fluid channel 204 is defined by etching the first substrate 201.

Furthermore, it is worth noting that the second substrate 203 shown in FIG. 3T is a silicon structure layer, which can be transferred from an SOI chip, and has a thickness of 1 to 5 μm, but is not limited thereto. The thickness of the second substrate 203 can be adjusted according to design requirements. The second substrate 203 is divided into three areas: a through hole 2031, a vibration part 2032, and a fixed part 2033. The through hole 2031 is located at the center, the vibration part 2032 is located at the peripheral area of the through hole 2031, and the fixed part 2033 is located at the peripheral area of the second substrate 203.

In addition, it is worth noting that the second bonding layer 205 shown in FIG. 3T is silicon oxide with a thickness of 1 to 5 μm. The thickness of the first bonding layer 202 can be equal to the thickness of the second bonding layer 205, and its thickness can be 1.1 μm, but it is not limited to this. The thickness of the first bonding layer 202 and the thickness of the second bonding layer 205 can also be unequal, and can be adjusted according to design requirements. The second bonding layer 205 is stacked on the second substrate 203.

In addition, it is worth noting that the third substrate 206 shown in FIG. 3T is a silicon structure layer, which can be transferred from an SOI chip, and has a thickness of 10~20μm, but is not limited thereto. The thickness of the third substrate 206 can be adjusted according to design requirements; the third substrate 206 is stacked on the second bonding layer 205 to form a resonance chamber 2061; the third substrate 206 has an actuating portion 2063 and a peripheral portion 2065, and the outer ring of the actuating portion 2063 has a third fluid channel 2062 and a connecting portion 2064, and the connecting portion 2064 is used to connect the actuating portion 2063 and the peripheral portion 2065.

It is worth noting that the second substrate 203 and the third substrate 206 can be single crystal silicon, polycrystalline silicon or amorphous silicon. The second substrate 203 and the third substrate 206 can also be made using a deposition or thinning process.

The piezoelectric component 207 further includes a lower electrode layer 2071, a piezoelectric layer 2072, an insulating layer 2073 and an upper electrode layer 2074. The piezoelectric layer 2072 is stacked on the lower electrode layer 2071; the insulating layer 2073 is laid on a portion of the surface of the piezoelectric layer 2072 and a portion of the surface of the lower electrode layer 2071, wherein the insulating layer 2073 is electrically insulating; the upper electrode layer 2074 is stacked on the insulating layer 2073 and on the remaining surface of the piezoelectric layer 2072 where the insulating layer 2073 is not provided. It is worth noting that the piezoelectric layer 2072 is circularly disposed above the actuating portion 2063 of the third substrate 206, so that the actuating portion 2063 is also circular. In addition, it is worth noting that the diameter of the piezoelectric layer 2072 is 140~500μm, but it is not limited to this. The diameter of the piezoelectric layer 2072 can be adjusted according to the overall size of the microfluidic pump 20. In addition, it is worth noting that the diameter ratio of the piezoelectric layer 2072 to the actuating portion 2063 is in the range of 1:1.3~1:3.6. In other words, the size of the piezoelectric layer 2072 is smaller than the size of the actuating portion 2063.

Through the actuation of the piezoelectric component 207, the actuator 2063 also vibrates up and down, and the vibrating part 2032 of the second substrate 203 vibrates in different phases, so that the resonance chamber 2061 forms a negative pressure, and the fluid passes through the first fluid channel 2012 from the fluid groove 2011, and then passes through the second fluid channel 204, and continues to flow through the resonance chamber 2061 through the through hole 2031 of the second substrate 203, and finally passes through the third fluid channel 2062 of the third substrate 206 to complete the fluid delivery. It is worth noting that the actuation frequency of the actuator 2063 is in the high frequency range of 0.1~1.5MHz, so that the microfluid can accumulate a small amount to generate more flow, but it is not limited to this. The actuation frequency of the actuator 2063 can be adjusted by the design of the overall microfluid pump 20. In addition, it is worth noting that the actuator 2063 is circular and has a diameter of 400-550 μm, but is not limited thereto. The shape and size of the actuator 2063 can also be adjusted by the design of the overall microfluidic pump 20.

The working voltage of the microfluid pump 20 is 2~12V. It is worth mentioning that the working voltage of the microfluid pump 20, the operating frequency of the actuator 2063 of the third substrate 206, the thickness of the third substrate 206 and the resonance of the vibration part 2032 of the second substrate 203 will all affect the delivery volume and efficiency of the fluid.

In addition, it is worth noting that the main difference between the second embodiment and the first embodiment is that the third substrate 206 has an etched depth. The improved feature is that because the space of the resonance chamber 2061 is increased, the squeeze film damping can be appropriately reduced, and when the piezoelectric component 207 is actuated to drive the actuating portion 2063 of the third substrate 206 to vibrate, it is less likely to produce a stiction effect with the vibrating portion 2032 of the second substrate 203.

Please refer to FIG. 4S, which is a third embodiment of the microfluid pump of the present invention. The main difference from the first embodiment is that the second bonding layer 305 is a composite structure of silicon oxide-polysilicon-silicon oxide. In this embodiment, the microfluid pump 30 comprises a first substrate 301, a first connecting layer 302, a second substrate 303, a second connecting layer 305, a third substrate 306 and a piezoelectric component 307. The first substrate 301 is provided with a fluid through groove 3011 and at least one first fluid channel 3012, wherein the fluid through groove 3011 is a deep groove; the first substrate 301, the first connecting layer 302 and the second substrate 303 are stacked from bottom to top in sequence and define a second fluid channel 304, wherein a through hole 3031 is provided at the top of the second fluid channel 304, and the through hole 3031 is located at the center of the second substrate 303, and the outer periphery of the through hole 3031 is surrounded by a vibrating portion 3032, and the vibrating portion 3032 is surrounded by a fixing portion 3033; the second substrate 303, the second connecting layer 305 and the third substrate 306 are provided with a vibrating portion 3032, and the vibrating portion 3032 is surrounded by a fixing portion 3033; 6 are stacked from bottom to top, and define a resonance chamber 3061; the third substrate 306 further includes at least one third fluid channel 3062, an actuating portion 3063, a connecting portion 3064 and a peripheral portion 3065, wherein the peripheral portion 3065 is arranged around the periphery of the actuating portion 3063, and the peripheral portion 3065 is coupled to the actuating portion 3063 through the connecting portion 3064, and the third fluid channel 3062 The third substrate 306 is penetrated, so that the third fluid channel 3062 and the resonance chamber 3061 can be connected to the second fluid channel 304, the first fluid channel 3012, and the fluid channel 3011 in sequence through the through hole 3031; the piezoelectric component 307 is stacked on the actuator 3063, including a lower electrode layer 3071, a piezoelectric layer 3072, an insulating layer 3073, and an upper electrode layer 3074.

Please refer to Figures 1A to 1C and Figures 4A to 4S. As shown in Figure 4A, step 1. prepare a first substrate 301. It is worth noting that the first substrate 301 is a silicon substrate (Si) with a thickness of 270~430μm, but not limited to this.

As shown in FIG. 4B, step 2. Etching an upper surface of the first substrate 301 to form at least one first groove 301A. It is worth noting that this etching method can be physical or chemical etching.

As shown in FIG. 4C, step 3. Etching the upper surface of the first substrate 301 to form a second groove 301B, wherein the first groove 301A is located at the bottom of the second groove 301B. It is worth noting that this etching method can be physical or chemical etching.

As shown in FIG. 4D, step 4. depositing a first bonding layer 302 on the surface of at least one first groove 301A and a second groove 301B of the first substrate 301. It is worth noting that the first bonding layer 302 is formed on the surface of the first substrate 301 by physical vapor deposition or chemical vapor deposition or thermal oxidation. The first bonding layer 302 is silicon oxide with a thickness ranging from 1 to 5 μm.

As shown in FIG. 4E, step 5. prepare the third substrate 306. It is worth noting that the third substrate 306 can be a silicon-on-insulation layer (SOI) wafer, but is not limited thereto.

As shown in FIG. 4F, step 6. depositing the second bonding layer 305 on the surface of the third substrate 306. It is worth noting that the second bonding layer 305 further includes at least one polysilicon layer 3052, and the lower layer 3051 and the upper layer 3053 of the polysilicon layer 3052 are each covered by a silicon oxide layer, but not limited to this. In addition to silicon oxide layer-polysilicon layer-silicon oxide layer, the second bonding layer 305 may also have multiple polysilicon layers 3052, such as silicon oxide layer-polysilicon layer-silicon oxide layer-polysilicon layer-silicon oxide layer.

As shown in FIG. 4G, step 7. patterning the second connecting layer 305. It is worth noting that after step 7. patterning the second connecting layer 305, a resonance chamber 3061 is generated. It is worth noting that the second connecting layer 305 has an etching depth, so that the space of the resonance chamber 3061 shown in FIG. 4S is increased, the squeeze film damping is appropriately reduced, and when the piezoelectric component 307 is actuated to drive the actuating portion 3063 of the third substrate 306 to vibrate, it is less likely to produce a stiction effect with the vibrating portion 3032 of the second substrate 303.

As shown in FIG. 4H, step 8. prepare the second substrate 303, and bond the second substrate 303 and the patterned second bonding layer 305 of the third substrate 306 to each other. It is worth noting that the second substrate 303 can be a silicon-on-insulation layer (SOI) wafer, but is not limited thereto.

As shown in Figure 4I, step 9. removes part of the second substrate 303. It is worth noting that the remaining thickness of the second substrate 303 after step 9. removes part of the second substrate 303 is in the range of 1-5μm.

As shown in FIG. 4J, step 10. patterning the second substrate 303. It is worth noting that after step 10. patterning the second substrate 303, the second substrate 303 is divided into a through hole 3031, a vibration portion 3032 and a fixed portion 3033.

As shown in FIG. 4K, step 11. The surface of the first substrate 301 having at least one first groove 301A and a second groove 301B is bonded to the second substrate 303. It is worth noting that the order of bonding the second substrate 303 to the third substrate 306 is prior to bonding the second substrate 303 to the first substrate 301. The order of bonding the substrates is considered to avoid the yield problem of the microfluid pump 30 caused by poor bonding during bonding. Therefore, bonding the second substrate 303 to the third substrate 306 first and then to the first substrate 301 can improve the bonding yield.

As shown in FIG. 4L, step 12. removes part of the third substrate 306. It is worth noting that the remaining thickness of the third substrate 306 after the part of the third substrate 306 is removed in step 12. ranges from 5 to 20 μm.

As shown in Figure 4M, step 13. Sequentially deposit the lower electrode layer 3071 and the piezoelectric layer 3072 on the third substrate 306.

As shown in Figure 4N, step 14. Patterning and etching the lower electrode layer 3071 and the piezoelectric layer 3072.

As shown in FIG. 40, step 15. depositing an insulating layer 3073 and patterning and etching the insulating layer 3073.

As shown in Figure 4P, step 16. depositing the upper electrode layer 3074 and patterning and etching the upper electrode layer 3074.

As shown in FIG. 4Q, step 17. patterning the insulating layer 3073 and the third substrate 306. It is worth noting that after step 17. patterning the insulating layer 3073 and the third substrate 306, at least one third fluid channel 3062 is generated, and the third substrate 306 is divided into an actuating portion 3063 and at least one peripheral portion 3065, wherein at least one connecting portion 3064 connects the actuating portion 3063 and the peripheral portion 3065, and at least one third fluid channel 3062 is also between the actuating portion 3063 and the peripheral portion 3065. In addition, it is worth noting that the lower electrode layer 3071, the piezoelectric layer 3072, the insulating layer 3073 and the upper electrode layer 3074 located on the actuating portion 3063 of the third substrate 306 are the piezoelectric component 307. In addition, it is worth noting that the piezoelectric layer 3072 is circularly arranged above the actuating portion 3063 of the third substrate 306, so that the actuating portion 3063 is also circular.

As shown in FIG. 4R, step 18. patterning and etching the lower surface of the first substrate 301.

As shown in FIG. 4S, step 19. Etch the first bonding layer 302. The production of the microfluidic pump 30 is completed.

It is worth noting that the fluid channel 3011 shown in FIG. 4S is segmented etching, which solves the problem of excessive etching angle or high aspect ratio etching in the previous technology, and reduces the flow resistance of the fluid flowing through the first fluid channel 3012. In addition, the first connecting layer 302 is silicon oxide, but the thickness is adjusted to 1~5μm, which can avoid the stress peeling problem caused by bonding with the second substrate 303. In addition, the second fluid channel 304 is defined by etching the first substrate 301.

Furthermore, it is worth noting that the second substrate 303 shown in FIG. 4S is a silicon structure layer, which can be transferred from an SOI chip, and has a thickness of 1 to 5 μm, but is not limited thereto. The thickness of the second substrate 303 can be adjusted according to design requirements. The second substrate 303 is divided into three areas: a through hole 3031, a vibration part 3032, and a fixed part 3033. The through hole 3031 is located at the center, the vibration part 3032 is located at the peripheral area of the through hole 3031, and the fixed part 3033 is located at the peripheral area of the second substrate 303.

In addition, it is worth noting that the second bonding layer 305 shown in FIG. 4S is a silicon oxide layer-polysilicon layer-silicon oxide layer with a thickness of 1-10 μm. The thickness of the first bonding layer 302 can be equal to the thickness of the second bonding layer 305, and its thickness can be 1.1 μm, but it is not limited to this. The thickness of the first bonding layer 302 and the thickness of the second bonding layer 305 can also be unequal, and can be adjusted according to design requirements. The second bonding layer 305 is stacked on the second substrate 303.

In addition, it is worth noting that the third substrate 306 shown in FIG. 4S is a silicon structure layer, which can be transferred from an SOI chip, and has a thickness of 10~20μm, but is not limited thereto. The thickness of the third substrate 306 can be adjusted according to design requirements; the third substrate 306 is stacked on the second bonding layer 305 to form a resonance chamber 3061; the third substrate 306 has an actuating portion 3063 and a peripheral portion 3065, and the outer ring of the actuating portion 3063 has a third fluid channel 3062 and a connecting portion 3064, and the connecting portion 3064 is used to connect the actuating portion 3063 and the peripheral portion 3065.

It is worth noting that the second substrate 303 and the third substrate 306 can be single crystal silicon, polycrystalline silicon or amorphous silicon. The second substrate 303 and the third substrate 306 can also be made using a deposition or thinning process.

The piezoelectric component 307 further includes a lower electrode layer 3071, a piezoelectric layer 3072, an insulating layer 3073, and an upper electrode layer 3074. The piezoelectric layer 3072 is stacked on the lower electrode layer 3071; the insulating layer 3073 is laid on a portion of the surface of the piezoelectric layer 3072 and a portion of the surface of the lower electrode layer 3071, wherein the insulating layer 3073 is electrically insulating; and the upper electrode layer 3074 is stacked on the insulating layer 3073 and on the remaining surface of the piezoelectric layer 3072 where the insulating layer 3073 is not provided. It is worth noting that the piezoelectric layer 3072 is circularly disposed above the actuating portion 3063 of the third substrate 306, so that the actuating portion 3063 is also circular. In addition, it is worth noting that the diameter of the piezoelectric layer 3072 is 140~500μm, but it is not limited to this. The diameter of the piezoelectric layer 3072 can be adjusted according to the overall size of the microfluidic pump 30. In addition, it is worth noting that the diameter ratio of the piezoelectric layer 3072 to the actuating portion 3063 ranges from 1:1.3 to 1:3.6. In other words, the size of the piezoelectric layer 3072 is smaller than the size of the actuating portion 3063.

Through the actuation of the piezoelectric component 307, the actuator 3063 also vibrates up and down, and the vibrating part 3032 of the second substrate 303 vibrates in different phases, so that the resonance chamber 3061 forms a negative pressure, and the fluid passes through the first fluid channel 3012 from the fluid groove 3011, and then passes through the second fluid channel 304, and continues to flow through the resonance chamber 3061 through the through hole 3031 of the second substrate 303, and finally completes the fluid delivery through the third fluid channel 3062 of the third substrate 306. It is worth noting that the actuation frequency of the actuator 3063 is in the high frequency range of 0.1~1.5MHz, so that the microfluid can accumulate a small amount to generate more flow, but it is not limited to this. The actuation frequency of the actuator 3063 can be adjusted by the design of the overall microfluid pump 30. In addition, it is worth noting that the actuator 3063 is circular and has a diameter of 400~550μm, but is not limited to this. The shape and size of the actuator 3063 can also be adjusted by the design of the overall microfluidic pump 30.

The working voltage of the microfluid pump 30 is 2~12V. It is worth mentioning that the working voltage of the microfluid pump 30, the operating frequency of the actuator 3063 of the third substrate 306, the thickness of the third substrate 306 and the resonance of the vibration part 3032 of the second substrate 303 will all affect the delivery volume and efficiency of the fluid.

In addition, it is worth noting that the main difference between the third embodiment and the first embodiment is that the second bonding layer 305 is a composite structure of silicon oxide-polycrystalline silicon-silicon oxide. The improved feature is that because the space of the resonance chamber 3061 is increased, the squeeze film damping can be appropriately reduced, and when the piezoelectric component 307 is actuated to drive the actuating portion 3063 of the third substrate 306 to vibrate, it is less likely to produce a stiction effect with the vibrating portion 3032 of the second substrate 303.

In summary, this case provides a method for manufacturing a microfluid pump, which uses a semiconductor process to complete the structure of the microfluid pump, so as to reduce the volume of the pump. In addition, the problem of etching the tapered first fluid channel in the prior art is improved, the flow resistance is reduced, and the efficiency of the fluid entering the microfluid pump is improved. In addition, in the second and third embodiments, the distance between the actuating portion of the third substrate and the vibrating portion of the second substrate is increased, the damping of the resonance chamber is reduced, and it is less likely to cause the actuating portion of the third substrate and the vibrating portion of the second substrate to produce a sticking effect, thereby increasing the service life of the microfluid pump. It has great industrial utilization value, and therefore an application is filed in accordance with the law.

This case can be modified in various ways by people familiar with this technology, but it will not deviate from the scope of protection of the attached patent application.

S1~S7: Steps

Claims (15)

A method for manufacturing a microfluidic pump comprises: preparing a first substrate; etching an upper surface of the first substrate to form at least one first groove; etching the upper surface of the first substrate to form a second groove, wherein the at least one first groove is located at the bottom of the second groove; depositing a first bonding layer on the surface of the at least one first groove and the second groove of the first substrate; preparing a third substrate; depositing a second bonding layer on the surface of the third substrate; pattern-etching the second bonding layer; preparing a second substrate, and bonding the second substrate and the pattern-etched second bonding layer of the third substrate. The first substrate is bonded to the second substrate; a portion of the second substrate is removed; the second substrate is patterned and etched; the surface of the first substrate having the at least one first groove and the second groove is bonded to the second substrate; a portion of the third substrate is removed; a lower electrode layer and a piezoelectric layer are sequentially deposited on the third substrate; the lower electrode layer and the piezoelectric layer are patterned and etched; an insulating layer is deposited and patterned and etched; an upper electrode layer is deposited and patterned and etched; the insulating layer and the third substrate are patterned and etched; a lower surface of the first substrate is patterned and etched; the first connecting layer is etched. A method for manufacturing a microfluidic pump as described in claim 1, wherein a resonant chamber is generated after patterning and etching the second follower layer. The manufacturing method of the microfluid pump as described in claim 1, wherein after patterning and etching the second substrate, the second substrate is divided into a through hole, a vibration portion and a fixed portion. The manufacturing method of the microfluid pump as described in claim 1, wherein after patterning the insulating layer and the third substrate, at least one third fluid channel is generated, and the third substrate is divided into an actuating portion and at least one peripheral portion, wherein at least one connecting portion connects the actuating portion and the peripheral portion, and the at least one third fluid channel is also between the actuating portion and the peripheral portion. The manufacturing method of the microfluid pump as described in claim 4, wherein the lower electrode layer, the piezoelectric layer, the insulating layer and the upper electrode layer located on the actuator portion of the third substrate are a piezoelectric component. A method for manufacturing a microfluidic pump as described in claim 1, wherein the order of bonding the second substrate to the third substrate takes precedence over bonding the second substrate to the first substrate. The manufacturing method of the microfluidic pump as described in claim 1, wherein the first connecting layer is formed on the surface of the first substrate by physical vapor deposition or chemical vapor deposition or thermal oxidation. The manufacturing method of the microfluidic pump as described in claim 1, wherein the second connecting layer is formed on the surface of the third substrate by physical vapor deposition or chemical vapor deposition or thermal oxidation. The manufacturing method of the microfluidic pump as described in claim 1, wherein the thickness of the first bonding layer ranges from 1 to 5 μm. The manufacturing method of the microfluidic pump as described in claim 1, wherein the thickness of the second bonding layer ranges from 1 to 10 μm. The manufacturing method of the microfluidic pump as described in claim 1, wherein the remaining thickness after removing part of the second substrate is in the range of 1-5μm. The manufacturing method of the microfluidic pump as described in claim 1, wherein the remaining thickness after removing part of the third substrate is in the range of 5-20μm. The manufacturing method of the microfluidic pump as described in claim 4, wherein the piezoelectric layer is circularly arranged above the actuating portion of the third substrate, and the actuating portion is also circular. The manufacturing method of the microfluid pump as described in claim 1, wherein after patterning and etching the second connecting layer, the method further includes etching the third substrate to a depth. In the manufacturing method of the microfluid pump as described in claim 1, when a second bonding layer is deposited on the surface of the third substrate, the second bonding layer further comprises at least one polycrystalline silicon layer, and the lower layer and the upper layer of the polycrystalline silicon layer are each covered by a silicon oxide layer.