KR20100128518A - Pcr chip using nanofluids and method for manufacuring pcr chip - Google Patents

Abstract

PURPOSE: A method for manufacturing PCR chip using nanofluid is provided to shorten temperature increase and decrease time of a chamber and temperature cycle for amplification. CONSTITUTION: A PCR chip comprises: an intermediate layer having a heater and sensor(50); an upper substrate having a first fluid channel; and a lower substrate having a second fluid channel for blocking and releasing chamber heat through nanofluid. The nanofluid contains titanium dioxide(TiO_2). A method for manufacturing the PCR chip comprises: a step of forming the intermediate layer; a step of forming the upper substrate and lower substrate; and a step of bonding the upper substrate, intermediate layer and lower substrate.

Description

Polymerase chain reaction chip using nanofluid and its manufacturing method {PCR chip using nanofluids and method for manufacuring PCR chip}

One aspect of the present invention relates to a microfabrication technology, and more particularly to a polymerase chain reaction chamber chip and a method of manufacturing the same.

The development of disease diagnosis chips, such as genetic disease diagnosis, must ensure the accuracy of the results and the ease of use. Until now, the disease diagnosis has been collected by the patient's blood or body fluid and sent to the analyst to inform the chemical analysis within hours or days.

Recent technology trends are incorporating fluid technology and microprocessing technology using MEMS (Microelectromechanical Systems) into existing analytical technologies. At this time, all components necessary for sample analysis can be miniaturized and integrated so that a small amount of liquid sample can be handled on a unit chip, and on-chip to be lab-on-a- chip).

In particular, one of the important parts in the production of lab-on-a-chip is the part for amplifying and culturing genes. Polymer chain reaction (PCR) is used for gene amplification and culture. PCR is one of the innovations in molecular biology of the century, and one of the most critical aspects of lab-on-a-chip implementation, the most difficult to integrate into microchips.

According to one aspect, a polymerase chain reaction chip capable of efficiently implementing gene amplification and culture of analytes present in a biological sample and a method of manufacturing the same are proposed.

According to one aspect, a polymerase chain reaction chip includes an intermediate layer including a heater and a sensor, a chamber accommodating the heater and the sensor, and a polymerase chain reaction of a sample, and a first material through which a reactant for polymerase chain reaction can flow. An upper substrate comprising a fluid channel and a lower substrate comprising a second fluid channel for blocking or dissipating heat in the chamber through the nanofluid.

Here, the chamber is formed below the upper substrate, and the heater and the sensor are formed above the intermediate layer. In addition, the nanofluid of the lower substrate blocks heat when the chamber is heated, and dissipates heat when cooled. The nanofluid may include titanium dioxide (TiO ₂ ).

Further, the chamber may be formed by etching through the anisotropic etching solution. The first fluid channel and the second fluid channel may be formed by etching through a micro blaster process.

Meanwhile, the polymerase chain reaction chip according to another aspect includes a top substrate, a heater, and a sensor, in which a heater and a sensor are formed, and including a first fluid channel through which a reactant for a polymerase chain reaction of a sample can flow. An intermediate layer including a chamber for performing the polymerase chain reaction, and a lower substrate including a second fluid channel for blocking or dissipating heat of the chamber through the nanofluid.

Here, the heater and the sensor are formed under the upper substrate, and the chamber is formed over the intermediate layer. In addition, the nanofluid of the lower substrate blocks heat when the chamber is heated, and dissipates heat when cooled. The nanofluid may include titanium dioxide (TiO ₂ ).

Further, the chamber may be formed by etching through the anisotropic etching solution. The first fluid channel and the second fluid channel may be formed by etching through a micro blaster process.

Meanwhile, a method of manufacturing a polymerase chain reaction chip according to another aspect includes forming a middle layer including a heater and a sensor, a chamber accommodating the heater and the sensor, and performing a polymerase chain reaction of a sample, and for a polymerase chain reaction. Forming an upper substrate including a first fluid channel through which a reactant can flow, forming a lower substrate including a second fluid channel for blocking or dissipating heat in the chamber through the nanofluid, and an upper substrate and an intermediate layer And bonding the lower substrate.

On the other hand, the polymerase chain reaction chip manufacturing method according to another aspect, the step of forming an upper substrate comprising a heater, a sensor and a first fluid channel through which the reactant for the polymerase chain reaction of the sample flows, the heater and the sensor Forming an intermediate layer including a chamber for accommodating and performing a polymerase chain reaction, forming a lower substrate including a second fluid channel for blocking or dissipating heat of the chamber through the nanofluid, and an upper substrate and an intermediate layer And bonding the lower substrate.

According to an embodiment, as the heater and the sensor are formed inside the chamber, it is possible to shorten the time of temperature rise and temperature drop of the chamber during the polymerase chain reaction. This can shorten the temperature cycle time for amplification in the polymerase chain reaction. In addition, the temperature of the sample can be measured in real time.

Furthermore, the temperature increase rate and the temperature decrease rate of the chamber can be improved through the nanofluid during the polymerase chain reaction. That is, when the chamber is heated, the temperature rise time can be shortened as the nanofluid is used as a heat shield. In contrast, when the chamber is cooled, the temperature drop time can be shortened as the nanofluid is used as a heat dissipating agent.

Furthermore, as the chamber is etched using an aqueous solution of tetramethylammonium hydroxide (TMAH), which is an anisotropic etching solution, the chamber is most stable and compatible with a CMOS process due to the high selectivity of silicon to an oxide film and proper anisotropy.

Furthermore, as the first fluid channel and the second fluid channel are etched through the micro blaster process, micro-abrasive particles accelerated by high pressure air or gas and sprayed through the micro nozzle are applied to the substrate having difficulty in micro machining. It can be etched in various forms.

Hereinafter, with reference to the accompanying drawings will be described embodiments of the present invention; In the following description of the present invention, if it is determined that detailed descriptions of related well-known functions or configurations may unnecessarily obscure the subject matter of the present invention, the detailed description thereof will be omitted. In addition, terms to be described below are terms defined in consideration of functions in the present invention, which may vary according to intention or custom of a user or an operator. Therefore, the definition should be based on the contents throughout this specification.

1 is a diagram illustrating a polymerase chain reaction chip (micro-PCR chip) 1 according to an embodiment of the present invention. Referring to FIG. 1, a polymerase chain reaction chip 1 according to an embodiment includes a chamber 10, a first type micro-fluidic channel 20, and a second fluid channel. (second type micro-fluidic channel) 30.

The polymerase chain reaction chip 1 analyzes analytes present in a biological sample by using polymerase chain reaction (PCR). Polymerase chain reaction is to connect each primer to the 3 'end side of two strands of DNA and perform DNA synthesis using DNA polymerase. The analyte may be any biological sample in which DNA exists.

The chamber 10 according to one embodiment houses a heater 40 and a sensor 50. That is, the heater 40 and the sensor 50 are not formed on the outside of the chamber 10, for example, the back of the chamber 10, but are housed in the chamber 10. According to one embodiment, in the case of the heater 40 and the sensor 50 embedded form, the chamber is formed at the bottom of the upper substrate of the polymerase chain reaction chip 1, and the heater and the sensor are at the top of the intermediate layer. Can be formed on. Alternatively, the heater and the sensor may be formed below the upper substrate, and the chamber may be formed above the intermediate layer.

If the heater and the sensor are formed outside the chamber, an error may occur when measuring the temperature of the sample, so temperature correction is necessary. For example, overshoot may occur when the set temperature is increased.

However, as described above, when the heater 40 and the sensor 50 are formed inside the chamber 10, the time for increasing the temperature and decreasing the temperature of the chamber 10 may be shortened. This can shorten the temperature cycle time for amplification in the polymerase chain reaction. In addition, the temperature of the sample can be measured in real time.

On the other hand, the first fluid channel (first type micro-fluidic channel) 20, the reaction material for the polymerase chain reaction during the polymerase chain reaction flows. Examples of the reactants may be DNA amplification agents.

On the other hand, the second fluid channel (second type micro-fluidic channel) 30 blocks or dissipates heat in the chamber 10 during polymerase chain reaction as nanofluids flow.

Nanofluid refers to a fluid in which nanoparticles having a particle size of 10 to 50 nm are uniformly dispersed and suspended in a fluid. When nanofluids are used as cooling fluids, they can increase heat transfer by increasing the thermal conductivity on their own as the temperature increases. In addition, the thermal conductivity is excellent. In addition, the critical heat flux is about three times faster than normal fluids.

According to one embodiment, the nanofluid includes titanium dioxide (TiO ₂ ). For example, nanofluid is a form in which titanium dioxide is mixed in ultrapure water (DI water) at a rate of 0.3wt%. In this case, it is possible to improve the thermal conductivity of up to 20% compared to the basic fluid is not mixed with the nanofluid.

The second fluid channel 30 serves as a heat-block and heat-sink of the chamber 10 using the above-described nanofluid. At this time, it is possible to improve the temperature increase rate and the temperature reduction rate of the chamber 10 through the nanofluid. That is, when the chamber 10 is heated, the temperature rise time may be shortened as the nanofluid is used as a heat shield. In contrast, when the chamber 10 is cooled, the temperature fall time can be shortened as the nanofluid is used as a heat dissipating agent.

2A and 2B are cross-sectional views of polymerase chain reaction chips 1a and 1a 'according to one embodiment of the present invention.

2A and 2B, the polymerase chain reaction chip 1a or 1a 'according to an embodiment may include an upper substrate 60 and a heater 40a including a first fluid channel 20a and a chamber 10a. ) And an intermediate layer 70 including the sensor 50a and a lower substrate 80 including the second fluid channel 30a or 30a '. The polymerase chain reaction chip 1a, 1a 'having the above-described structure is referred to as a first type polymerase chain reaction chip for convenience of description, and the term first type polymerase chain reaction chip is used in the following description. .

In the first type polymerase chain reaction chip 1a, 1a ', the upper substrate 60 includes a first fluid channel 20a and a chamber 10a through which the DNA amplification material can flow. The chamber 10a may be formed below the upper substrate 60. The material of the first fluid channel 20a and the chamber 10a of the upper substrate 60 may be a glass wafer, so that the DNA amplification sample may be easily identified by the eye during the reaction.

The chamber 10a may be formed by etching using an aqueous solution of tetramethylammonium hydroxide (TMAH) which is an anisotropic etching solution. The TMAH aqueous solution, a mixture of four cycles of ammonium, is the most stable of the aqueous ammonia-based solutions and is less toxic than those that can be used for other silicon wet etching solutions. In addition, the high selectivity of silicon to oxide and the proper anisotropy allow it to be used in integrated micromachining technology compatible with CMOS processes.

The intermediate layer 70 is integrated with the heater 40a and the sensor 50a. In this case, since the heater 40a and the sensor 50a are formed on the upper portion of the intermediate layer 70, the chamber 10a formed below the upper substrate 60 may receive the heater 40a and the sensor 50a described above. Can be. The material of the heater 40a and the sensor 50a of the intermediate layer 70 may be a silicon wafer, in order to maximize the cooling effect using silicon having excellent thermal conductivity.

The lower substrate 80 includes second fluid channels 30a and 30a ′ so that nanofluids, which serve as heat-blocks and heat-sinks, can flow. According to an embodiment, the nanofluid includes titanium dioxide (TiO ₂ ). The material of the second fluid channels 30a and 30a 'of the lower substrate 80 may be a silicon wafer or a glass wafer. Preferably, the material of the second fluid channels 30a and 30a' may be a silicon wafer.

The second fluid channels 30a and 30a 'may be of a meander type or a chamber type. FIG. 2A illustrates a first type polymerase chain reaction chip 1a including a curved second fluid channel 30a, and FIG. 2B illustrates a first type including a chamber-type second fluid channel 30a '. It is a figure which shows a type polymerase chain reaction chip 1a '.

In an embodiment, the second fluid channels 30a and 30a 'may be formed using a micro blaster etching process. Micro blaster is a kind of physical etching process device, in which micro-based abrasives, which are accelerated by high pressure air or gas and sprayed through a micro nozzle, can etch substrates having difficulty in micromachining in various forms.

3A and 3B are cross-sectional views of polymerase chain reaction chips 1b or 1b 'according to another embodiment of the present invention.

Referring to FIG. 3, the polymerase chain reaction chip 1b or 1b ′ according to another embodiment may include an upper substrate 60 and a chamber including a heater 40b, a sensor 50b, and a first fluid channel 20b. An interlayer 70 including 10b and a lower substrate 80 including a second fluid channel 30b or 30b 'are included. The polymerase chain reaction chip 1b, 1b 'having the above-described structure is referred to as a second type polymerase chain reaction chip for convenience of description, and the term second type polymerase chain reaction chip is used in the following description. .

In the second type polymerase chain reaction chips 1b and 1b ', the upper substrate 60 includes a heater 40b, a sensor 50b and a first fluid channel 20b. The heater 40b and the sensor 50b may be formed below the upper substrate 60. In this case, the material of the first fluid channel 20b may be a glass wafer, so that the DNA amplification sample may be easily identified by the eye during the reaction.

The intermediate layer 70 includes a chamber 10b. As the chamber 10b is formed above the intermediate layer 70, the chamber 10b may accommodate the heater 40b and the sensor 50b formed below the upper substrate. The chamber 10b may be formed by etching using an aqueous solution of tetramethylammonium hydroxide (TMAH) which is an anisotropic etching solution.

Meanwhile, the lower substrate 80 includes second fluid channels 30b and 30b 'such that nanofluids, which serve as heat-blocks and heat-sinks, can flow. According to an embodiment, the nanofluids 30b and 30b 'include titanium dioxide (TiO ₂ ). The material of the second fluid channels 30b and 30b 'of the lower substrate 80 may be a silicon wafer or a glass wafer. Preferably, the material of the second fluid channels 30b and 30b' may be a silicon wafer.

The second fluid channels 30b and 30b 'may be of a meander type or a chamber type. FIG. 3A shows a second type polymerase chain reaction chip 1b including a curved second fluid channel 30b, and FIG. 3B shows a second fluid channel 30b 'including a chamber type second fluid channel 30b'. 2 shows a type 2 polymerase chain reaction chip 1b '. According to an exemplary embodiment, the second fluid channels 30b and 30b 'are formed using a micro blaster etching process.

4 is a diagram illustrating a mask according to various embodiments of the first type polymerase chain reaction chips 1a and 1a ′ of FIGS. 2A and 2B. Figure 4 (a) is a view showing a mask of the polymerase chain reaction chip having a meander-type micro-fluidic channel, Figure 4 (b) is a chamber-type fluid channel (chamber-type) Figure shows a mask of a polymerase chain reaction chip having a micro-fluidic channel.

According to one embodiment, in the case of the first type polymerase chain reaction chips 1a and 1a ', the first fluid channel 20a and the chamber 10a of the upper substrate are manufactured by using a glass wafer to see a DNA amplification sample. Make it easy to observe. In order to maximize the cooling effect, the intermediate layer includes a heater 40a and a sensor 50a embedded in a silicon wafer having excellent thermal conductivity. The lower substrate is formed with a second fluid channel 30a or 30a 'to maximize the effects of heat-block and heat-sink using a glass or silicon wafer.

FIG. 5 illustrates a mask according to various embodiments of the second type polymerase chain reaction chips 1b and 1b ′ of FIGS. 3A and 3B. FIG. 5A illustrates a mask of a polymerase chain reaction chip having a meander-type micro-fluidic channel, and FIG. 5B illustrates a chamber-type fluid channel. Figure shows a mask of a polymerase chain reaction chip having a micro-fluidic channel.

According to one embodiment, in the case of the second type polymerase chain reaction chips 1b and 1b ', the chamber 10b of the intermediate layer is made of silicon having excellent thermal conductivity, and the first fluid channel 20b of the upper substrate is formed of a chamber. In order to easily observe the sample entering 10b, it is manufactured on a glass wafer, and the heater 40b and the sensor 50b are integrated on the upper substrate. The lower substrate is manufactured in the same manner as the first type polymerase chain reaction chips 1a and 1a '.

6 is a manufacturing process chart of the first type polymerase chain reaction chips 1a and 1a '.

Referring to FIG. 6, first, an initial cleaning of a silicon or glass wafer 601 is performed in order to manufacture a bottom glass / silicon of the first type polymerase chain reaction chips 1a and 1a '. (602).

Subsequently, a photoresist is laminated onto the cleaned silicon or glass wafer (603). In this case, according to an embodiment, a dry film resist (DFR) is laminated on the wafer. DFR is a kind of negative photoresist, and it is efficient in terms of quality improvement, cost reduction, and time saving because DFR can solve the existing spin coating process by simple lamination process.

After the mask is coated on the laminated photoresist, an agent capable of accommodating the nanofluid may be exposed by exposing a place for forming the second fluid channels 30a and 30a 'through an exposure and development process. Two fluid channel 30a, 30a 'patterns are formed (604). An I-Line UV light source may be used for the exposure process. In the development process, a solution in which DI water and Na ₂ Co ₃ are combined may be used.

Subsequently, the second fluid channels 30a and 30a 'are formed 605, and the pattern for the second fluid channels 30a and 30a' is removed. In this case, when the DFR is used to form the pattern for the second fluid channels 30a and 30a ', the DFR is removed and finally a lower substrate including the second fluid channels 30a and 30a' is completed.

The finally formed lower substrate is combined 606 with the upper substrate to be described later to manufacture the first type polymerase chain reaction chips 1a and 1a '. In this case, the upper substrate and the lower substrate may be bonded through polymer bonding using a dry film resist.

Meanwhile, the silicon wafer is subjected to a chemical mechanical polishing (CMP) process 610 to manufacture a middle silicon including the heater 40a and the sensor 50a, and then initial cleaning (611). In this case, for manufacturing the heater 40a and the sensor 50a, P-type silicon having a (100) orientation may be used.

Subsequently, prior to wet etching using an aqueous solution of tetramethylammonium hydroxide (TMAH), which is an anisotropic etching solution, a silicon wafer is placed in an oxidizing furnace to form a selective etch stop layer for wet anisotropic etching. In step 612, an oxide film is formed.

Subsequently, wet etching is performed on the silicon wafer on which the oxide film is formed by using a TMAH solution, and SiO ₂ is removed (SiO ₂ removal) 614.

Subsequently, after the oxide film is grown 615 on the silicon wafer from which SiO ₂ has been removed, platinum (Pt) / titanium (Ti) evaporation is performed (616). An e-beam evaporation may be used for the deposition process. Platinum (Pt) has the advantage of almost constant temperature resistance and wide temperature range.

Subsequently, after the photo process, the heater 40a and the sensor 50a are patterned 617, and then platinum (Pt) and titanium (Ti) are etched (Pt / Ti etching) 618. Here, platinum (Pt) etching may use aqua regia (hydrochloric acid: nitric acid = 3: 1), and titanium (Ti) etching may use an etching solution (D.I water: hydrofluoric acid: nitric acid = 50: 1: 1).

Meanwhile, in order to manufacture the top glass of the first type polymerase chain reaction chips 1a and 1a ', first, the glass wafer 631 is initially cleaned (632).

Subsequently, a photoresist is laminated to the cleaned silicon or glass wafer (633). In this case, according to an embodiment, a dry film resist (DFR) is laminated on the wafer.

After the mask is coated on the laminated photoresist, the first fluid channel 20a is exposed by exposing a place where the first fluid channel 20a and the chamber 10a are to be formed through an exposure and development process. And the chamber 10a pattern (634).

Subsequently, the first fluid channel 20a and the chamber 10a are formed 635, and the patterns for the first fluid channel 20a and the chamber 10a are removed. At this time, when the DFR is used to form the pattern for the first fluid channel 20a and the chamber 10a, the DFR is removed, and finally an upper substrate including the first fluid channel 20a and the chamber 10a is manufactured. do.

The prepared upper substrate is combined with the lower substrate described above to form polymerase chain reaction chips 1a and 1a '. In this case, the lower substrate and the upper substrate may be bonded 636 through polymer bonding using a dry film resist.

7 is a manufacturing process diagram of the second type polymerase chain reaction chips 1b and 1b '.

Referring to FIG. 7, first, an initial cleaning of a silicon or glass wafer 701 is performed to manufacture a bottom glass / silicon of the second type polymerase chain reaction chips 1b and 1b ′. (702).

Subsequently, photoresist is laminated to the cleaned silicon or glass wafer (703). In this case, according to an embodiment, a dry film resist (DFR) is laminated on the wafer.

After the mask is coated on the laminated photoresist, an agent capable of accommodating the nanofluid may be exposed by exposing a place where the second fluid channels 30b and 30b 'will be formed through an exposure and development process. Two fluid channel 30b, 30b 'patterns are formed (704).

Subsequently, the second fluid channels 30b and 30b 'are formed (705), and the pattern for the second fluid channels 30b and 30b' is removed. In this case, when the DFR is used to form the pattern for the second fluid channels 30b and 30b ', the DFR is removed and finally a lower substrate including the second fluid channels 30b and 30b' is formed.

The finally formed lower substrate is combined with the upper substrate, which will be described later, to be manufactured as second type polymerase chain reaction chips 1b and 1b '. In this case, the upper substrate and the lower substrate may be bonded through polymer bonding using a dry film resist.

Meanwhile, the silicon wafer is subjected to a chemical mechanical polishing (CMP) process 610 to manufacture a middle silicon including the chamber 10b, and then initial cleaning (711). In this case, for manufacturing the chamber 10b, P-type silicon having a (100) orientation may be used.

Subsequently, prior to wet etching using an aqueous solution of tetramethylammonium hydroxide (TMAH), an anisotropic etching solution, a silicon wafer is placed in an oxidizing furnace to form a selective etch stopper for wet anisotropic etching (Oxidation). An oxide film is formed through (713).

Then forming the intermediate layer (Middle silicon) comprising a chamber (10b), as do the wet etching using TMAH solution to the silicon wafer an oxide film is formed 714, and remove the _{SiO 2 (SiO 2 Removal) (} 715) do.

Meanwhile, in order to manufacture the top glass of the second type polymerase chain reaction chips 1b and 1b ', the glass wafer 730 is initially cleaned (Initial Cleaning) (731).

Subsequently, photoresist is laminated to the cleaned glass wafer (732). In this case, according to an embodiment, a dry film resist (DFR) is laminated on the wafer.

After the mask is coated on the laminated photoresist, the first fluid channel 20b pattern is formed by exposing a place where the first fluid channel 20b is to be formed through an exposure and development process. (733). Subsequently, via holes are formed in the pad portions of the heater 40b and the sensor 50b for the three-dimensional wiring process (734).

Then, the first fluid channel 20b is formed 735, and the pattern for the first fluid channel 20b is removed. Here, when the DFR is used to form the pattern for the first fluid channel 20b, the DFR is removed.

Subsequently, the via hole formed in the via hole forming process 734 is filled with silver paste using dispensing equipment (736). In operation 736, platinum (Pt) / titanium (Ti) evaporation is performed. An e-beam evaporation may be used for the deposition process.

Subsequently, after the photo process, the heater 40b and the sensor 50b are patterned (PR pattering) 738 and then the platinum (Pt) and titanium (Ti) are etched (Pt / Ti etching) 739 as the heater 40b. ) And the intermediate layer on which the sensor 50b is formed are manufactured. In this case, platinum (Pt) etching may use aqua regia (hydrochloric acid: nitric acid = 3: 1), and titanium (Ti) etching may use an etching solution (D.I water: hydrofluoric acid: nitric acid = 50: 1: 1).

The upper substrate finally formed is combined with the lower substrate 740 described above to manufacture the second type polymerase chain reaction chips 1b and 1b '. The lower substrate and the upper substrate may be bonded by polymer bonding using a dry film resist.

8 is a flowchart illustrating a first fluid channel manufacturing process using a micro blaster process according to an exemplary embodiment of the present invention.

Referring to FIG. 8, a photoresist is laminated on a glass wafer 800 to manufacture the first fluid channels 20a and 20b (800). In this case, according to an embodiment, a dry film resist (DFR) is laminated on the wafer.

In addition, the first fluid channels 20a and 20b are defined through the photo process (810), and the photoresist is removed (820). Subsequently, a micro blaster process for forming an inlet and an outlet is performed 830, and the pattern for the first fluid channels 20a and 20b is removed 840. At this time, when the DFR is used to form the pattern for the first fluid channels 20a and 20b, the DFR is removed.

9 is a diagram for describing a micro blaster process, according to an exemplary embodiment.

Referring to FIG. 9, a DFR is used as a protective layer to prevent the glass from being etched during the glass wafer etching using the micro blaster process. Then, as shown in Figure 9 after the etching process to form a microfluidic channel and a micro chamber.

At this time, according to one embodiment, the movement speed of the nozzle is 10000p / s, the injection pressure is 400kPa, the movement interval of the nozzle can be set to 0.5mm. Based on the etching conditions of the above-described micro blaster is prepared for the capacity of each chamber.

10 illustrates a fluid channel according to various embodiments of the present disclosure.

FIG. 10A illustrates the first fluid channel 20a and the chamber 10a of the upper substrate of the first type polymerase chain reaction chips 1a and 1a '. The first fluid channel 20a according to an embodiment has a width of 200 μm and a depth of 300 μm.

FIG. 10B shows the first fluid channel 20b of the upper substrate of the second type polymerase chain reaction chips 1b and 1b '. The first fluid channel 20b according to an embodiment has a width of 200 μm and a depth of 150 μm. The length of the inlet is 6 mm and the length of the outlet can be 5 mm.

10 (c) and 10 (d) show second fluid channels of the lower substrate. The second fluid channels 30a and 30b shown in FIG. 10C have a meander type of 200 μm in width, 500 μm in depth, and 32 mm in length. The second fluid channels 30a 'and 30b' shown in FIG. 10 (d) have a chamber type of 200 mu m in width, 500 mu m in depth and 40 mm in length.

FIG. 11 is a view taken by a scanning electron microscope the cross section of the fluid channel etched by the pattern protection by the DFR according to an embodiment.

FIG. 11A illustrates a first fluid channel of the upper substrate, and FIG. 11B illustrates a meander type second fluid channel of the lower substrate, and FIG. 11C. Are the chamber type second fluid channels of the lower substrate, respectively.

12 is a flowchart illustrating a chamber manufacturing using a TMAH etching technique according to an embodiment.

Referring to FIG. 12, a TMAH etching technique is used to manufacture the chamber 10b of the second type polymerase chain reaction chips 1b and 1b '. The TMAH aqueous solution, a 4-cycle ammonium mixture, is less toxic than aqueous solutions that can be used for other silicon wet etching, and is used in integrated micromachining technology that is compatible with CMOS processes due to the high selectivity of silicon to the oxide film and proper anisotropy. It is suitable to

In the silicon etching 1230 using TMAH solution, the (100) plane and the (111) plane, which are the crystal directions of silicon, are simultaneously formed, but the (111) crystal plane, which is the side surface, has an etch rate 400 times slower than that of the (100) crystal plane. Therefore, the two surfaces are etched along the crystal plane of about 54.74 ° by the angle of contact.

According to one embodiment, a P-type silicon wafer having a thickness of 500 μm, a crystal plane of (100) and a double-side polished is used for fabricating the chamber. Here, the silicon wafer is placed in a mixed solution of H ₂ SO ₄ : H ₂ O ₂ = 4: 1 or more for 20 minutes, and then in a mixed solution of HF: DI water = 10: 1 for about 10 seconds. Remove and wash with DI water.

Before wet etching 1230 using a TMAH solution, a wafer was placed in an oxidizing furnace to form a selective etch stopper for wet anisotropic etching, followed by a wet oxidation process at 1100 ° C. for 3 hours to form an oxide film having a thickness of about 1 μm. (1200)

The photoresist AZ1512 PR is coated on both surfaces of the wafer, and a photo process is performed to define a chamber region (1210).

Subsequently, the oxide film is etched using BOE (Buffed Oxide Etch) until the silicon wafer surface is exposed. After removing the PR by inserting the etched wafer into the acetone solution (1220), the defined region is placed in a 20 wt%, 85 ° C. TMAH receiving solution to form a chamber (1230). In addition, silicon around the chamber is removed by back etching to minimize heat loss caused by silicon.

The oxide film used as the etch stop film is removed by putting it in an HF solution (1240), and then, an oxide film having a thickness of 1 μm is formed in an oxide furnace again to form an insulating film (1250).

FIG. 13 is a view illustrating an etching form, a cross section of the chamber, and an outer surface of the chamber formed through the TMAH etching of FIG. 12.

FIG. 13A illustrates an etching form of the (100) wafer, and FIG. 13B illustrates a cross section of the chamber of the polymerase chain reaction chip. In addition, Figure 13 (c) shows the outer surface of the chamber.

14 is a diagram illustrating a heater and a sensor manufactured according to various embodiments.

FIG. 14A shows a heater 40a and a sensor 50a of the first type polymerase chain reaction chips 1a and 1a ', and FIG. 14B shows a second type polymerase chain. It is a figure which shows the heater 40b and the sensor 50b of reaction chip 1b, 1b '.

In the case of the first type polymerase chain reaction chips 1a and 1a ', a heater 40a and a sensor 50a are manufactured on a silicon wafer as an intermediate layer. According to one embodiment, first, in order to see the heat-block and heat-sink effects of nanofluids, an oxide film was grown on a 250 μm thick wafer after a chemical mechanical polishing (CMP) process on an interlayer silicon wafer. After Ti 300 Å / Pt 2000 증착 by using an ion beam evaporator. After the photo process, the heater 40a and the sensor 50a are patterned and then the heater 40a and the sensor 50a are formed by etching Pt using aqua regia (hydrochloric acid: nitric acid = 3: 1). Ti is removed using an etching solution (D.I: hydrofluoric acid: nitric acid = 50: 1: 1).

Meanwhile, in the case of the second type polymerase chain reaction chips 1b and 1b ', a heater 40b and a sensor 50b are manufactured on a glass wafer which is a material of an upper substrate. At this time, the heater 40b and the sensor 50b are manufactured by depositing Ti / Pt in the same manner as the first type polymerase chain reaction chips 1a and 1a 'described above. In addition, a via hole is formed through a micro blaster process, and a silver paste is filled using a dispensing apparatus to be directly connected to the lower part and the upper part.

FIG. 15 illustrates a polymerase chain reaction chip prepared through DFR conjugation according to an embodiment. Figure 15 (a) shows a first type polymerase chain reaction chip, Figure 15 (b) shows a second type polymerase chain reaction chip.

Referring to (a) and (b) of FIG. 15, polymer bonding using DFR, which enables a low temperature bonding process, is performed on each of the three parts. According to an embodiment, after laminating the DFR to the lower substrate glass after the CMP process, the lower substrate, the intermediate layer, and the upper substrate are bonded at a temperature of 90 ° C. at a temperature of 1 MPa for 30 minutes. Subsequently, the prepared polymerase chain reaction chip is attached to the PCB substrate and wire bonding is performed.

Referring to FIG. 15, a fixing pin and a silicon tube are first attached to the mold to form an inlet hole and an outlet hole through which the fluid channel will pass. Then, the PDMS solution mixed with PDMS (Polydimethylsiloxane) and a catalyst (catalyst) in 10: 1 is poured and cured at 70 ° C. for 4 hours. The prepared inlet hole and the outlet hole are bonded to two surfaces to be bonded to the fluid channel part after the plasma treatment by using an O ₂ plasma treatment equipment. It is then coded with silicon rubber to protect the wire bonding portion.

16 is a diagram illustrating a polymerase chain reaction chip connected to a second fluid channel through which a nanofluid flows.

17 to 20 are diagrams for explaining the thermal characteristics of the micro polymerase chain reaction chip through the TiO ₂ nanofluid.

According to one embodiment, TiO ₂ nanofluid is used as a heat-block and heat-sink of the polymerase chain reaction chip 1. CFD-ACE +, a computational fluid program capable of flow analysis, may be used for thermal characterization according to an embodiment. Since thermal simulations are based on heat distribution due to temperature rise, transient simulations are performed based on the steady-state simulation results. Therefore, in the above-described thermal characteristic analysis, the effect on the cooling case is analyzed based on the influence of the nanofluid flow on the temperature rise.

According to one embodiment, in order to analyze the heat distribution of the polymerase chain reaction chip, the heat distribution is confirmed by transient state analysis of the temperature change of the polymerase chain reaction chip when the heater portion goes up to 94 ° C. The total analysis step number is 2500 times and the time step is 0.0001 seconds.

FIG. 17 is a view showing a thermal distribution (a) and a temperature (b) of a cross section of a polymerase chain reaction chip having a meander type silicon second fluid channel, and FIG. 18 is a meander type glass A diagram showing the heat distribution (a) and the temperature (b) of the cross section of the polymerase chain reaction chip having a second fluid channel.

As shown in Figs. 17 and 18, when the second fluid channel is of the meander type, the flow of nanofluid into the silicon second fluid channel is lower than that of flowing nanofluid into the glass second fluid channel. Temperature distribution.

On the other hand, Figure 19 is a view showing the thermal distribution (a) and the temperature of the cross-section (b) of the polymerase chain reaction chip having a chamber-type silicon second fluid channel (b), Figure 20 is a chamber (chamber) The heat distribution diagram (a) and the temperature (b) of the chip cross section of the polymerase chain reaction chip having the free second fluid channel of).

As shown in FIGS. 19 and 20, when the second fluid channel is chamber type, the flow of nanofluid into the silicon second fluid channel is lower than the flow of nanofluid into the glass second fluid channel. Temperature distribution.

As shown in FIGS. 17 to 20, when comparing simulation results of four types (flexible silicon / glass second fluid channel and chamber-type silicon / glass second fluid channel), silicon is used as the second fluid channel. And the second fluid channel type exhibits a lower temperature distribution when it is chambered.

The transient analysis results can be applied to the heating and cooling of the chip when applied to the nanofluid polymerase chain reaction chip. The heating of the polymerase chain reaction chip is controlled so that there is no flow of the nanofluid. Heat loss can occur due to the high thermal conductivity of silicon (168 W / mK). However, according to one embodiment, the nanofluid serves as a heat-block because the thermal conductivity (0.611 W / m · K) of the nanofluid is much lower than that of silicon. Therefore, heat loss can be prevented. On the other hand, if the flow to the nanofluid as shown in Figure 17 to 20 as the nanofluid acts as a heat-sink (heat-sink) during the cooling of the polymerase chain reaction chip can lower the temperature even more quickly. .

The embodiments of the present invention have been described above. Those skilled in the art will appreciate that the present invention can be implemented in a modified form without departing from the essential features of the present invention. Therefore, the disclosed embodiments should be considered in an illustrative rather than a restrictive sense. The scope of the present invention is shown in the claims rather than the foregoing description, and all differences within the scope will be construed as being included in the present invention.

1 is a view showing a polymerase chain reaction chip according to an embodiment of the present invention,

2a and 2b is a cross-sectional view of the polymerase chain reaction chip according to an embodiment of the present invention,

Figure 3a and 3b is a cross-sectional view of the polymerase chain reaction chip according to another embodiment of the present invention,

4 is a diagram illustrating a mask according to various embodiments of the first type polymerase chain reaction chip of FIGS. 2A and 2B;

FIG. 5 illustrates a mask according to various embodiments of the second type polymerase chain reaction chip of FIGS. 3A and 3B;

6 is a manufacturing process chart of the first type polymerase chain reaction chip,

7 is a manufacturing process chart of the second type polymerase chain reaction chip,

8 is a process diagram of manufacturing a first fluid channel using a micro blaster process according to an embodiment of the present invention;

9 is a view for explaining a micro blaster process according to an embodiment;

10 illustrates a fluid channel according to various embodiments of the present disclosure.

11 is a cross-sectional view taken through a scanning electron microscope of a fluid channel etched by the pattern protection by the DFR according to an embodiment,

12 is a manufacturing process diagram of a chamber using a TMAH etching technology, according to an embodiment

FIG. 13 is a view illustrating an etching form of a chamber formed through the TMAH etching of FIG. 12, a cross section of the chamber, and an outer surface of the chamber;

14 is a view illustrating a heater and a sensor manufactured according to various embodiments;

FIG. 15 illustrates a polymerase chain reaction chip prepared through DFR conjugation according to an embodiment.

16 is a diagram illustrating a polymerase chain reaction chip connected to a second fluid channel through which a nanofluid flows, according to an embodiment;

17 to 20 are diagrams for explaining the thermal characteristics of the micro polymerase chain reaction chip through the TiO ₂ nanofluid.

<Description of the symbols for the main parts of the drawings>

1, 1a, 1a ', 1b, 1b': polymerase chain reaction chip

10, 10a, 10b: chamber 20, 20a, 20b: first fluid channel

30, 30a, 30a ', 30b, 30b': second fluid channel

40: heater 50: sensor

Claims (23)

An intermediate layer comprising a heater and a sensor; An upper substrate accommodating the heater and the sensor and including a chamber for performing a polymerase chain reaction of a sample and a first fluid channel through which a reactant for the polymerase chain reaction can flow; And A polymerase chain reaction chip comprising a lower substrate including a second fluid channel for blocking or dissipating heat in the chamber through nanofluids. The method of claim 1, The chamber is formed under the upper substrate, the heater and the sensor is a polymerase chain reaction chip, characterized in that formed on top of the intermediate layer. The method of claim 1, wherein the nanofluid of the lower substrate The polymerase chain reaction chip, characterized in that the heat is cut off when the chamber is heated, the heat is released during cooling. The method of claim 1, The polymer fluid chain reaction chip, characterized in that the nanofluid comprises titanium dioxide (TiO ₂ ). The method of claim 1, The polymer of the polymerase chain reaction chip, characterized in that the material of the heater and the sensor formed in the intermediate layer is a silicon wafer. The method of claim 1, The material of the chamber and the first fluid channel formed on the upper substrate is a polymerase chain reaction chip, characterized in that the sample to identify the glass wafer. The method of claim 1, The polymerase chain reaction chip, characterized in that the material of the second fluid channel formed in the lower substrate is a silicon wafer. The method of claim 1, The second fluid channel of the lower substrate is a polymerase chain reaction chip, characterized in that the flow of the nanofluid (chamber type) or curved type (meander type) smooth. The method of claim 1, The chamber is a polymerase chain reaction chip, characterized in that formed by etching through an anisotropic etching solution. The method of claim 1, The first fluid channel and the second fluid channel is a polymerase chain reaction chip, characterized in that formed by etching through a micro blaster (micro blaster) process. The method of claim 1, The intermediate layer, the lower substrate and the upper substrate is a polymerase chain reaction chamber chip, characterized in that bonded through the polymer (Polymer Bonding) using a dry film resist (Dry Film Resist). An upper substrate including a first fluid channel through which a heater and a sensor are formed and through which a reactant for a polymerase chain reaction of a sample can flow; An intermediate layer containing the heater and the sensor and including a chamber for performing the polymerase chain reaction; And A polymerase chain reaction chip comprising a lower substrate including a second fluid channel for blocking or dissipating heat in the chamber through nanofluids. 13. The method of claim 12, The heater and the sensor is formed under the upper substrate, the chamber is a polymerase chain reaction chip, characterized in that formed on top of the intermediate layer. The method of claim 12, wherein the nanofluid of the lower substrate The polymerase chain reaction chip, characterized in that the heat is cut off when the chamber is heated, the heat is released during cooling. 13. The method of claim 12, The nanofluid is a polymerase chain reaction chip comprising titanium dioxide (TiO ₂ ). 13. The method of claim 12, The material of the first fluid channel of the upper substrate is a polymerase chain reaction chip, characterized in that the glass wafer for identifying the sample. 13. The method of claim 12, Polymerization chain reaction chip, characterized in that the material of the chamber formed in the intermediate layer is a silicon wafer. 13. The method of claim 12, The second fluid channel formed on the lower substrate is a polymerase chain reaction chip, characterized in that the flow of the nano-fluid chamber (chamber type) or curved type (meander type) smooth. 13. The method of claim 12, The chamber is a polymerase chain reaction chip, characterized in that formed by etching through an anisotropic etching solution. 13. The method of claim 12, The first fluid channel and the second fluid channel is a polymerase chain reaction chip, characterized in that formed by etching through a micro blaster (micro blaster) process. 13. The method of claim 12, The intermediate layer, the lower substrate and the upper substrate is a polymerase chain reaction chamber chip, characterized in that bonded through the polymer (Polymer Bonding) using a dry film resist (Dry Film Resist). Forming an intermediate layer comprising a heater and a sensor; Forming an upper substrate containing the heater and the sensor and including a chamber for performing a polymerase chain reaction of a sample and a first fluid channel through which a reactant for the polymerase chain reaction can flow; Forming a lower substrate including a second fluid channel for blocking or dissipating heat of the chamber through nanofluid; And Polymerization chain reaction chip manufacturing method comprising the step of bonding the upper substrate, the intermediate layer and the lower substrate. Forming an upper substrate including a heater, a sensor, and a first fluid channel through which a reactant for polymerase chain reaction of the sample can flow; Forming an intermediate layer containing the heater and the sensor and including a chamber for performing the polymerase chain reaction; Forming a lower substrate including a second fluid channel for blocking or dissipating heat of the chamber through nanofluid; And Polymerization chain reaction chip manufacturing method comprising the step of bonding the upper substrate, the intermediate layer and the lower substrate.

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