CN1203995C - Microfluidic module - Google Patents

Abstract

The invention relates to a micro-fluidic module, which uses a barrier layer of a micro-fluidic flow channel, and is provided with an actuating element, a fluid injection cavity, a plurality of fluid output channels and fluid inlet channels with tapered geometric shapes, wherein the actuating element such as a heater is used for heating working fluid to generate thermal bubbles, the working fluid is injected to the outside by means of instantaneous high pressure of the generated thermal bubbles, and the compressed working fluid is discharged through the fluid output channels, and is supplemented by the fluid inlet channels, so that the flow field directions of the working fluid flowing in the fluid injection cavity are consistent, the flow field directions of adjacent fluid injection cavities are opposite, and the whole body presents a single flow direction, thereby greatly increasing the backfill speed of the working fluid and simultaneously improving the operating frequency of the system.

Description

Microfluidic module

technical field

The invention relates to a microfluidic module, which is applied to the manufacturing industry related to microelectromechanical systems, in particular to a microfluidic module with consistent flow field direction.

Background technique

The rapid progress of science and technology in today's society has brought people a more convenient life, especially in the research and development of micro-electromechanical systems (MEMS, Micro-Electro Mechanical Systems). In recent years, the domestic semiconductor and information electronics industry has continued to flourish and has become the main force of my country's product exports. As electronic products continue to become "light, thin and short", the accuracy and size of various components and processing equipment that affect their use are becoming increasingly stringent, which has also contributed to another wave of manufacturing technology revolution, towards ultra-precision , high-density, high-speed, intelligent, and miniaturization, etc., and then derived the "Next Generation Manufacturing Technology" (Next Generation Manufacturing Technology) required by the industry in the 21st century. The main development directions of next-generation manufacturing technology are two major projects: nanotechnology (Nano Technology) and MEMS technology. The former is a manufacturing technology with a processing accuracy in the range of 10 ² nm to 10 ^-1 nm; the latter is a system that uses nano and micro processing technology to develop micro components and components, and integrates microelectronic circuits and controllers.

Among them, related technologies of microfluidics, common microfluidic nozzles such as inkjet print heads (InkJet Print Head), injectors (Injector) and other related applications of various fluid ejection components, have gradually become an important direction of research and development. Please refer to FIG. 1A , which is a schematic diagram of a conventional microfluidic flow channel structure, in which a single fluid channel 13 flows into the ejection cavity 15 of the barrier layer 12 . Therefore, when the heater 11 heats the working fluid in the injection chamber 15 to generate hot bubbles, they are sprayed out of the outside by instantaneous pressure, and at the same time part of the working fluid is pushed out from the fluid channel 13 . Then, the hot air bubbles on the heater 11 dissipate, and at this time, the supplementary tank 14 provides the working fluid, and fills the injection cavity 15 through the fluid channel 13 again. It can be known from the above that the direction of the flow field of the working fluid is from inside to outside when spraying, and from outside to inside when replenishing, both of which are carried out through the fluid channel 13 .

However, the injection action of the nozzle hole of the adjacent injection cavity causes the working fluid in the adjacent injection cavity to be attracted and cause the liquid level to be unstable, resulting in the interference phenomenon of "Cross talk", and the speed of backfilling of the working fluid will definitely slow down. The frequency of nozzle operation cannot be effectively increased. For the same design, please refer to FIG. 1B, which is a schematic diagram of the flow field of the existing microfluidic flow channel. Among them, U.S. Patent No. 6,042,222 discloses that when the heater 11 performs the injection action, the injection and backfilling of the working fluid supplement the two action cycles. The direction of the flow field in the fluid channel 13 is in the opposite direction. Therefore, the fluid flow resistance generated by the working fluid will seriously slow down the speed of fluid backfilling and replenishment during spraying and supplementary backfilling, thereby seriously affecting the operating frequency of the nozzle.

Contents of the invention

In view of the above problems in the prior art, the purpose of the present invention is to overcome the deficiencies and defects of the prior art, and provide a microfluidic module that guides the flow of the working fluid by using the alternate operation of the microfluidic flow channel and the driving sequence.

To achieve the above-mentioned purpose, a microfluidic module of the present invention includes a plurality of groups of micro-motion units, each micro-motion unit includes a barrier layer of a microfluidic flow channel, a fluid injection cavity, an actuating element, and a plurality of tapered Type fluid inlet channel and fluid output channel. Among them, the fluid injection cavity is arranged on the barrier layer of the microfluidic flow channel to store the working fluid; the actuating element such as a heater is installed inside the fluid injection cavity to heat the working fluid to generate hot bubbles, a plurality of The fluid output channel and the fluid inlet channel are set on both sides of the barrier layer of the microfluidic flow channel; more particularly, the fluid output channel and the fluid inlet channel have a tapered geometry, so that a port has a larger cross-section , while the opposite port has a smaller cross-section, so the working fluid is easy to enter from the large port and flow out from the other small port; It is easy to enter the fluid injection cavity from the large port, and the relatively small port can prevent the working fluid from backflow; at the same time, the large port of the microfluidic channel on the other side of the fluid injection cavity communicates with the fluid injection cavity, so that The working fluid stored in the fluid ejection cavity can easily flow out from the microfluidic channel on this side. In addition, the actuation elements of adjacent micro-motion units are input with different driving timings. Therefore, when the working fluid stored in the fluid injection cavity is heated by the actuating element to generate hot bubbles, an instantaneous pressure is generated, so that part of the working fluid is ejected to the outside; The fluid output channel is drained.

In addition, the flow of the working fluid in the micro-motion unit has a single direction by virtue of the tapered geometry of the fluid inlet channel and the fluid output channel. According to a microfluidic module of the present invention, the direction of tapering of the microfluidic flow channels of adjacent micro-motion units is opposite, so that the working fluid flow direction of adjacent micro-motion units is opposite. When a plurality of micro-motion units are connected in series When assembled, the flow direction of the overall working fluid presents an "S" shape; and with the help of different driving sequences, it avoids the interference phenomenon that the working fluid level is unstable due to the simultaneous driving of adjacent micro-motion units, so not only the working The fluid can be backfilled faster and the system can be operated more frequently.

A microfluidic module disclosed in the present invention utilizes the structure of the fluid inlet channel and the fluid output channel to have a tapered geometry, so that the flow field direction of the working fluid in the micro-motion unit is consistent, and according to different requirements, the microfluidic The barrier layer of the fluid flow channel can be changed in different types, and a plurality of fluid inlet channels and fluid output channels can also be opened separately, so that the working fluid in the system has different types of flow field movements; The driving sequence of the actuating element operates alternately to avoid the interference phenomenon of "Cross talk", thus greatly increasing the speed of backfilling and replenishing the working fluid, and at the same time increasing the operating frequency of the system.

Description of drawings

Figure 1A is a schematic diagram of the structure of an existing microfluidic flow channel;

Figure 1B is a schematic diagram of the flow field of an existing microfluidic flow channel;

2 is a schematic diagram of a first embodiment of the microfluidic module of the present invention;

3A is a schematic diagram of the movement of the microfluidic module of the present invention;

Fig. 3B is the experimental data table of the microfluidic module of the present invention;

4 is a schematic diagram of a second embodiment of the microfluidic module of the present invention;

5 is a schematic diagram of a third embodiment of the microfluidic module of the present invention;

6 is a schematic diagram of a fourth embodiment of the microfluidic module of the present invention;

7 is a schematic diagram of a fifth embodiment of the microfluidic module of the present invention;

Fig. 8 is a schematic diagram of the sixth embodiment of the microfluidic module of the present invention.

Explanation of symbols in the figure

10 micro unit

11 heater

12 Barrier layer

13 Fluid channel

14 Supplementary Slots

15 injection cavity

20 Microfluidic flow channel barrier layer

30 Fluid injection chamber

40 Actuating element 2

50 Fluid entry channel

51 Entry port

52 output port

60 microfluidic flow channels

70 Fluid replenishment tank

80 Fluid output channels

81 Entry port

82 output port

Detailed ways

According to a microfluidic module disclosed in the present invention, it is applied to the manufacturing industry related to micro-electromechanical systems. It utilizes the staggered flow field direction and the alternate operation of the driving sequence to guide the flow of the working fluid and cause The pressure source ejects the fluid out of the environment.

A microfluidic module according to the present invention, please refer to FIG. 2 , which is a schematic diagram of the first embodiment of the microfluidic module of the present invention, wherein the microfluidic unit 10 includes a microfluidic flow channel barrier layer 20 and a fluid ejection cavity 30 , wherein the fluid ejection chamber 30 is arranged in the barrier layer 20 of the microfluidic flow channel to store the working fluid, and also includes an actuating element 40, which is installed inside the fluid ejection chamber 30, and an electric potential is input from the outside The differential signal generates a pressure source, and the actuating element 40 is usually a piezoelectric ceramic heater. The actuating element 40 is installed inside the fluid injection cavity 30 to heat the working fluid stored in the injection cavity 30; the two sides of the microfluid flow channel barrier layer 20 are respectively provided with a fluid inlet channel 50 and a fluid output channel 80, both of which have tapered geometry. Wherein the inlet port 51 at the left end of the fluid inlet channel 50 has a larger cross-section, and the output port 52 at the right end has a relatively smaller cross-section, so the working fluid enters easily from the inlet port 51 with a larger cross-section, and from the smaller one. The output port 52 of the cross section exits. Similarly, the left end of the fluid output channel 80 has an inlet port 81 with a larger cross-section, and the other end has an output port 82 with a smaller cross-section. That is to say, the fluid inlet channel 50 and the fluid output channel 80 communicate with the fluid injection cavity 30, and the fluid injection cavity 30 communicates with the working fluid through the fluid output channel 80 and the fluid input channel 50, and replenishes the tank with the stored fluid. The working fluid supplied by 70, and the fluid inlet channel 50 is from the outside of the microfluidic flow channel barrier layer 20 to the fluid ejection cavity 30, which is a tapered cross section, and the fluid output channel 80 is from the fluid ejection cavity 30 to the microfluidic flow channel The outside of the barrier layer 20 is also tapered in cross-section.

Here is a detailed description of the actual operation of the working fluid. Please refer to FIG. 3A, which is a schematic diagram of the movement of the microfluidic module of the present invention. The thermal energy of the working fluid is provided by the actuating element 40 to generate hot air bubbles and the instantaneous pressure of the fluid injection cavity. Therefore, Through the upper nozzle hole (not shown in the figure) of the fluid injection cavity 30, part of the working fluid is ejected to the outside, and at the same time, it is affected by the instantaneous pressure of the hot bubbles in the fluid injection cavity 30, and the rest of the working fluid will pass through the micro In the fluid output channel 80 on the right side of the fluid flow channel barrier layer 20 , the inlet port 81 with a larger cross-section is pushed to the microfluidic flow channel 60 . Then, the working fluid supplied by the fluid supplement tank 70 flows in the microfluidic flow channel 60 . Then, the fluid ejection chamber 30 has the phenomenon of uneven pressure between the fluid ejection chamber 30 and the external channel 60 due to the dissipation of the hot air bubbles at this time; The barrier layer 20 for the microfluid flow channel fills the fluid ejection cavity 30 with the working fluid through the output port 52 . The characteristics of the working fluid, or general fluid, are described here. When subjected to instantaneous pressure, the fluid will flow accordingly; however, when the working fluid faces an inlet port 51 with a larger cross-section, and an output port with a smaller cross-section 52, it is naturally easy to flow in the direction of the inlet port 51 with a larger cross-section. From the above, it can be seen that the working fluid easily flows from the inlet port 81 of the larger cross-section of the fluid output channel 80 on the right side of the fluid injection cavity 30 , and then flows out to the channel 60 through the output port 82 of the smaller cross-section. Similarly, the working fluid flows through the fluid inlet channel 50 on the left side of the microfluidic flow channel barrier layer 20, enters through the inlet port 51 with a larger cross-section, and then is guided to the fluid injection cavity by the input port 52 at the other end within 30. In addition, the fluid inlet channel 50 on both sides of the microfluidic flow channel barrier layer 20 is in the same direction as the fluid output channel 80, so that the flow of the working fluid in the fluid injection cavity 30 is in the same direction, and the actions of injection and filling Through different microfluidic channels 50, the backfilling speed of the working fluid is increased, and the operating frequency of the overall system is also increased accordingly.

As shown in FIG. 3A , the adjacent micro-motion units 10 have opposite geometric shapes of the fluid inlet channel 50 and the fluid output channel 80 tapering, so the flow direction of the working fluid in the adjacent micro-motion units 10 is opposite, and has Such as an "S"-shaped flow field direction; moreover, according to the microfluidic module of the present invention, the driving timings of the actuating elements 40 of adjacent micromotion units 10 are different. That is to say, when a micro-motion unit 10 is spraying, the adjacent micro-motion unit 10 stops moving; as can be seen from the above, when multiple groups of micro-motion units 10 are installed, the working fluid of each micro-motion unit 10 The direction of the flow field is opposite, and the driving sequence is also different, so that the interference phenomenon that the adjacent working fluid is attracted and the liquid level is unstable can be prevented.

Please refer to FIG. 3B , which is an experimental data table of the microfluidic module of the present invention. We can find from this data that the stable value of the injection flow rate of the working fluid in the existing technology is about 2.7c.c./min, and the frequency response at this time is 5KHz. However, under the same working environment, the embodiment disclosed in the present invention has a stable injection flow rate of 3.3 c.c./min and a frequency response of 7 KHz. Therefore, from the data in the actual experiment, it can be clearly understood that compared with the existing structure, the microfluidic module disclosed by the present invention not only provides high-frequency injection movement, but also has better fluid injection flow stability. value.

The tapered geometry of the fluid inlet channel 50 and the fluid output channel 80 and the number of installations are not limited, and the purpose is to make the working fluid easily enter from the inlet port with a larger cross-section. Here is another embodiment for illustration. Please refer to FIG. 4 , which is a schematic diagram of the second embodiment of the microfluidic module of the present invention, in which a plurality of fluid inlets are respectively opened on opposite sides of the barrier layer 20 of the microfluidic flow channel. The channel 50 and the fluid output channel 80 have a tapered geometric structure; in particular, one side of the microfluidic flow channel barrier layer 20 is provided with two fluid inlet channels 50, and the other side is provided with two fluid output channels 80; such a design makes the working fluid compressed by the instantaneous pressure generated by the heated air bubbles be guided out of the fluid ejection cavity 30 more quickly through the fluid output channel 80, and the lost working fluid passes through the barrier layer 20 of the microfluidic flow channel The fluid enters the channel 50 and is quickly replenished, thereby stabilizing the liquid level of the working fluid in the fluid injection cavity 30 .

According to the microfluidic module disclosed in the present invention, the positions of the fluid inlet channel 50 and the fluid output channel 80 are not limited to the opposite sides of the barrier layer 20 of the microfluidic flow channel, as shown in FIG. Schematic diagram of the third embodiment of the flow module, wherein one side of the microfluidic flow channel barrier layer 20 is provided with a fluid inlet channel 50 with a tapered geometry as in the above-mentioned first embodiment, and the adjacent side is provided with a fluid output channel 80. Different from the above-mentioned embodiments, in the third embodiment, the working fluid stored in the fluid injection cavity has a flow field direction that turns, so different effects can be produced according to the usage conditions, and the application is more flexible.

For another preferred embodiment, please refer to FIG. 6 , which is a schematic diagram of a fourth embodiment of the microfluidic module of the present invention. The microfluidic modules disclosed in the present invention can also be arranged in a matrix. As shown in the figure, the fluid inlet channel 50 has an inlet port 51 with a larger cross-section, and an output port 52 with a smaller cross-section, so that the fluid inlet channel 50 is in a tapered state in a straight line or a geometric function, so that the working fluid can It easily flows in from the inlet port 51 and flows out from the outlet port 52 . Similarly, like the fluid inlet channel 50 , the fluid outlet channel 80 has an inlet port 81 with a larger cross-section and an outlet port 82 with a smaller cross-section at its two ends, and is tapered in a straight line or a geometric function. The microfluidic flow channel 20 is provided with two fluid injection cavities 30, and an actuating element 40 is installed inside it, and two fluid output channels 80 and a fluid inlet channel 50 are respectively communicated with one fluid injection cavity 30, so that the working fluid The direction of the flow field is to flow from the fluid inlet channel 50 into the injection chamber 30 , and then flow out through the fluid output channel 80 . The difference between this embodiment and the above-mentioned embodiments is that two fluid injection chambers 30 are provided and two fluid output channels 80 are provided, so that the working fluid can move smoothly in a limited space.

Here is another embodiment, please refer to FIG. 7, which is a schematic diagram of the fifth embodiment of the microfluidic module of the present invention, wherein the fluid inlet channel 50 and the fluid output channel 80, the two ports and the tapered shape are as mentioned above , the difference is that the microfluidic flow channel barrier layer 20 is provided with four fluid injection cavities 30, and the fluid injection cavities 30 are circular, so that the working fluid moves smoothly in the injection cavities 30, and reduces the rectangular shape. The resistance generated by the fluid ejection cavity 30 .

The microfluid flow channel barrier layer 20 may be in any shape other than a rectangle. As shown in FIG. 8 , it is a schematic diagram of the sixth embodiment of the microfluidic module of the present invention. Wherein the microfluidic flow channel barrier layer 20 has a hexagonal shape, and the design of this structure is like a honeycomb pattern, and there are channels 60 between the adjacent microfluidic flow channel barrier layers 20, which can supply working fluid flow. A plurality of fluid inlet channels 50 and fluid output channels 80 are respectively set on one side of the microfluidic flow channel barrier layer 20, as in the embodiment disclosed above, the design of tapered or geometric function makes the working fluid flow from The fluid inlet passage 50 is filled into the fluid injection cavity 30 and flows out through the fluid outlet passage 80. This design changes the opening directions of the fluid inlet passage 50 and the fluid outlet passage 80, thereby controlling the flow of the working fluid. Field direction, so different effects can be produced according to different needs, and the use is more flexible.

The above descriptions are only preferred embodiments of the present invention, and are not used to limit the implementation scope of the present invention; that is, all equivalent changes and modifications made according to the scope of the claims of the present invention are covered by the claims of the present invention .

Claims (19)

1. Microflow module, is characterized in that this Microflow module includes in order to guide the working fluid that a fluid supplemental tank is supplied with:

One microfluid circulation road barrier layer includes:

One fluid spray chamber body is opened in this microfluid circulation road barrier layer, in order to store working fluid to be sprayed;

One fluid admission passage, be opened in a side of this microfluid circulation road barrier layer with the convergent pattern of straight line or geometric function, make the two ends of this fluid admission passage have the entry port of big cross section and the output port of smaller cross-sectional area respectively, and this output port is connected with this fluid ejection chamber body;

One fluid output channel, be opened in the opposite side of this microfluid circulation road barrier layer with the convergent pattern of straight line or geometric function, make the two ends of this fluid admission passage have the entry port of big cross section and the output port of smaller cross-sectional area respectively, and this entry port is connected with this fluid ejection chamber body; And

One activates element, is installed in the inside of this fluid ejection chamber body, in order to this working fluid one pressure source to be provided;

Wherein be subjected to the influence of pressure that this actuation element provides, make the working fluid that is stored in this fluid ejection chamber body eject the external world, and by the convergent pattern of this fluid admission passage and this fluid output channel, make hard pressed this working fluid smooth-goingly certainly this fluid output channel flow out this injection cavity, simultaneously be complemented at this fluid ejection chamber body via this fluid admission passage backfill.

2. Microflow module as claimed in claim 1 is characterized in that, this actuation element is a heater, by outside input potential difference signal and supply with this working fluid heat energy, and makes this working fluid be subjected to the influence of heat energy and produces injection action.

3. Microflow module as claimed in claim 1 is characterized in that, the material of this actuation element is a piezoceramic material.

4. Microflow module as claimed in claim 1 is characterized in that, this microfluid circulation road barrier layer is an arbitrary polygon.

5. Microflow module as claimed in claim 1 is characterized in that, the kenel of this fluid ejection chamber body is an arbitrary polygon.

6. Microflow module as claimed in claim 1 is characterized in that, this microfluid circulation road barrier layer more includes a plurality of these fluid admission passages that are connected with this fluid ejection chamber body, in order to promote the speed that backfill replenishes this working fluid.

7. Microflow module as claimed in claim 1 is characterized in that, this microfluid circulation road barrier layer more includes a plurality of these fluid output channels that are connected with this fluid ejection chamber body, in order to promote the speed that this working fluid flows out this fluid ejection chamber body.

8. Microflow module as claimed in claim 1, it is characterized in that, this microfluid circulation road barrier layer more includes a plurality of these fluid ejection chamber bodies, and the both sides of this microfluid circulation road barrier layer offer a plurality of these fluid admission passages and a plurality of this fluid output channel that is communicated with this fluid ejection chamber body more respectively.

9. Microflow module as claimed in claim 8, it is characterized in that, this fluid admission passage that this adjacent fluid ejection chamber body is communicated with, the convergent direction of its straight line or geometric function is opposite, and this fluid output channel, the convergent direction of its straight line or geometric function is opposite, makes working fluid in this adjacent fluid ejection chamber body, its flow direction have uniformity and presents the flow field direction of serpentine.

10. Microflow module, is characterized in that this Microflow module includes in order to guide the working fluid that a fluid supplemental tank is supplied with:

A plurality of microfluid circulation road barrier layers, each this microfluid circulation road barrier layer includes:

One or more fluid ejection chamber body, each this fluid ejection chamber body are opened in this microfluid circulation road barrier layer, in order to store working fluid;

One or more fluid admission passage, each this fluid admission passage is opened in a side of this microfluid circulation road barrier layer with the convergent pattern of straight line or geometric function, make the two ends of this fluid admission passage have the entry port of big cross section and the output port of smaller cross-sectional area respectively, and this output port is connected with this fluid ejection chamber body;

One or more fluid output channel, each this fluid output channel is opened in the opposite side of this microfluid circulation road barrier layer with the convergent pattern of straight line or geometric function, make the two ends of this fluid admission passage have the entry port of big cross section and the output port of smaller cross-sectional area respectively, and this entry port is connected with this fluid ejection chamber body; And

A plurality of actuation elements, each this actuation element is installed in the inside of this fluid ejection chamber body respectively, in order to this working fluid one pressure source to be provided;

Wherein be subjected to the influence of pressure that this actuation element provides, make the working fluid that is stored in this fluid ejection chamber body eject the external world, and by the convergent pattern of this fluid admission passage and this fluid output channel, make hard pressed this working fluid smooth-goingly certainly this fluid output channel flow out this injection cavity, simultaneously be complemented at this fluid ejection chamber body via this fluid admission passage backfill.

11. Microflow module as claimed in claim 10 is characterized in that, this actuation element is a heater, by outside input potential difference signal and supply with this working fluid one heat energy, and makes this working fluid be subjected to the influence of this heat energy and produces injection action.

12. Microflow module as claimed in claim 10 is characterized in that, the material of this actuation element is a piezoceramic material.

13. Microflow module as claimed in claim 10 is characterized in that, this fluid output channel that this microfluid circulation road barrier layer one side is offered is corresponding to this fluid admission passage of this adjacent microfluid circulation road barrier layer one side.

14. Microflow module as claimed in claim 10 is characterized in that, this fluid admission passage that this microfluid circulation road barrier layer one side is offered is corresponding to this fluid output channel of this adjacent microfluid circulation road barrier layer one side.

15. Microflow module as claimed in claim 10 is characterized in that, a side of this microfluid circulation road barrier layer offers this fluid admission passage and this fluid output channel simultaneously.

16. Microflow module as claimed in claim 10 is characterized in that, this adjacent microfluid circulation road barrier layer be arranged as the matrix pattern.

17. Microflow module as claimed in claim 10 is characterized in that, this microfluid circulation road barrier layer is an arbitrary polygon.

18. Microflow module as claimed in claim 10 is characterized in that, the arrangement of this adjacent microfluid circulation road barrier layer is the pattern of honeycomb nido.

19. Microflow module as claimed in claim 10 is characterized in that, the kenel of this fluid ejection chamber body is an arbitrary polygon.

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