Micro gas chromatograph expiration molecule sample injection MEMS (Micro Electro Mechanical System) chip and chromatograph

Abstract

The embodiment of the invention provides a micro gas chromatograph expiration molecule sample injection MEMS chip and a chromatograph, and relates to the technical field of thermal desorption equipment, the chip comprises: a substrate having a porous structure, a sample injection port and a sample outlet, the pore wall of the porous structure is provided with an adsorption material, the sample injection port is located at one side of the porous structure, and the sample outlet is located at the other side of the porous structure; the sample outlet is positioned on the other side of the porous structure; the cover plate is arranged on one side of the substrate; the heating assembly is arranged on the other side of the substrate, and the heating assembly is used for heating the substrate; the temperature measuring assembly is arranged on the same side of the heating assembly, and the temperature measuring assembly is used for measuring the temperature of the substrate in real time. According to the embodiment of the invention, the porous structure is arranged in the substrate, and the adsorption material is arranged on the hole wall of the porous structure, so that gas adsorption and desorption are realized, and chip and miniaturization of a traditional desorption instrument are realized.

Description

Technical Field

[0001] The present application relates to the technical field of thermal desorption sampling devices, and in particular to a micro gas chromatograph exhaled breath molecule sampling MEMS chip and a chromatograph. Background Art

[0002] In the related technology, thermal desorption sampling is the process of extracting and concentrating volatiles from complex matrices and quickly entering GC or GC / MS analysis. Thermal desorbers are essential pre-treatment equipment in VOC analysis laboratories. The current thermal desorption sampling device is bulky and cannot effectively distinguish regions when loading different materials, and cannot perform regional thermal desorption; at the same time, the existing thermal desorption sampling device does not have sufficient thermal contact surface with the material, resulting in the need for long-term heating to achieve higher thermal desorption efficiency. Summary of the invention

[0003] The present application aims to solve at least one of the technical problems existing in the prior art. To this end, the present application proposes a micro gas chromatograph exhaled breath molecule sampling MEMS chip and an exhaled breath molecule analysis chromatograph, which can effectively reduce the volume.

[0004] In one aspect, an embodiment of the present application provides a micro gas chromatograph exhaled breath molecule injection MEMS chip, comprising:

[0005] A substrate having a porous structure, an injection port and an outlet port, wherein the pore wall of the porous structure is provided with an adsorption material, the injection port is located on one side of the porous structure, and the outlet port is located on the other side of the porous structure;

[0006] A cover plate, disposed on one side of the base plate;

[0007] A heating component is disposed on the other side of the substrate, and the heating component is used to heat the substrate;

[0008] The temperature measuring component is arranged on the same side of the heating component, and the temperature measuring component is used to measure the temperature of the substrate in real time.

[0009] Furthermore, the porous structure is arranged close to one of the end surfaces of the substrate, and the porous structure is distributed along the end surface of the substrate, wherein the cover plate is sealingly connected to the end surface provided with the porous structure.

[0010] Furthermore, the adsorption material is deposited on the pore walls of the porous structure by an atomic layer deposition process.

[0011] Furthermore, the thickness of the substrate is 400 μm to 650 μm.

[0012] Furthermore, the substrate is a silicon wafer, the cover plate is glass, and the cover plate is connected to the substrate through an anodic bonding process.

[0013] Furthermore, the thickness of the heating component is set to 100nm~500nm.

[0014] Furthermore, it also includes a temperature measuring component, which is arranged on a side of the substrate away from the cover plate, and there is a gap between the temperature measuring component and the heating component.

[0015] Furthermore, the thickness of the temperature measuring component is set to 100nm~500nm.

[0016] Further, at least one of the sample inlet and the sample outlet is obtained by dry etching; and / or the porous structure is obtained by photolithography.

[0017] Another aspect of the present application is disclosed in an embodiment of a breath molecule analysis chromatograph, comprising the above-mentioned micro gas chromatograph breath molecule injection MEMS chip.

[0018] It can be seen from the above technical solutions that the embodiments of the present application have at least the following beneficial effects:

[0019] In the micro gas chromatograph exhaled breath molecule injection MEMS chip provided in the embodiment of the present application, a porous structure is made on the substrate, and an adsorbent material is arranged in the pore wall of the porous structure, and the adsorbent material can be used to adsorb gas molecules. In practical applications, after the gas molecules enter the substrate from the injection port, they can flow through the porous structure and flow out from the sample outlet. When the gas molecules flow through the porous structure, the adsorbent material arranged on the pore wall of the porous structure can adsorb the gas molecules. During thermal desorption, the substrate is heated by a heating component, so that the gas molecules can be desorbed from the adsorbent material and flow out from the sample outlet. In the embodiment of the present application, a porous structure is arranged in the substrate, and the adsorbent material is arranged on the pore wall of the porous structure to realize gas adsorption and desorption. The desorption device is composed of structures such as a substrate and a cover plate, thereby realizing the chip design of a traditional thermal desorber, which is beneficial to reducing the volume of the thermal desorber and helping to realize the miniaturization of the thermal desorber. At the same time, the porous structure increases the specific surface area and improves the adsorption capacity of the MEMS chip for gas molecules. That is to say, under the premise of the same gas molecule adsorption amount, this embodiment can reduce the volume of the micro gas chromatograph exhaled molecule injection MEMS chip. In addition, by reducing the volume of the substrate, the heat transfer efficiency can be accelerated, so that the heat generated by the heating component can be quickly transferred to various positions of the porous structure, which can improve the thermal desorption efficiency and also help reduce the heating power of the heating component. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0021] Figure 1 A schematic diagram of the structure of a MEMS chip for exhaled breath molecule injection in a micro gas chromatograph provided in one embodiment of the present application.

[0022] Reference numerals:

[0023] 100, substrate; 110, porous structure; 120, sample inlet; 130, sample outlet;

[0024] 200, cover plate;

[0025] 300, heating component;

[0026] 400. Temperature measurement component. DETAILED DESCRIPTION

[0027] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0028] Thermal desorption sampling is the process of extracting and concentrating volatiles from complex matrices and quickly entering GC or GC / MS analysis. Thermal desorber is an essential pre-treatment equipment in VOC analysis laboratories.

[0029] In the related technology, the micro thermal desorber is a key component of the gas chromatograph. The thermal desorber is a device used to analyze the adsorbed gas or volatile organic compounds (VOCs) on the surface or in the pores of the material. Its main working principle is to use heat energy to desorb the substances adsorbed on the solid surface or adsorbent, and then separate them through the chromatographic column and detect and analyze them by the detector. Thermal desorption technology has a wide range of applications in many fields such as environmental monitoring, food safety, and materials science.

[0030] At present, with the development of micromotor technology, micro-nano processing technology has reduced the size (mass) of related equipment components, so the heating power demand has been reduced accordingly, but the power of the gas chromatograph (system) is still very high, which is a limiting factor in achieving high performance, miniaturization and long-term operation.

[0031] The MEMS (micro-electromechanical system) chip of the current breath molecular analysis chromatograph is large in size and cannot effectively distinguish between regions when loading different materials, and cannot perform regional thermal desorption. At the same time, the existing thermal desorption sampling device does not have sufficient thermal contact surface with the material, resulting in the need for long-term heating to achieve higher thermal desorption efficiency.

[0032] Aiming at the shortcomings of existing thermal desorbers, such as large volume and insufficient thermal contact surface, the present invention provides a thermal desorption chip of a micro gas chromatograph for breath analysis.

[0033] See also Figure 1 As shown, an embodiment of the present application discloses a micro gas chromatograph exhaled breath molecule injection MEMS chip, by making a porous structure 110 in a substrate 100, and setting a gas adsorption material in the pore wall of the porous structure 110, and then connecting a cover plate 200 to the substrate 100 to achieve sealing of the desorption chip, thereby realizing the chipization and miniaturization of the traditional desorber.

[0034] The following will be combined Figure 1 The micro gas chromatograph exhaled breath molecule injection MEMS chip disclosed in one embodiment of the present application is specifically explained and illustrated.

[0035] like Figure 1 The micro gas chromatograph exhaled breath molecule injection MEMS chip comprises a substrate 100, a cover plate 200, a heating component 300 and a temperature measuring component 400. Specifically, the substrate 100 has a porous structure 110, an injection port 120 and an outlet port 130, the pore wall of the porous structure 110 is provided with an adsorption material, the injection port 120 is located on one side of the porous structure 110, and the outlet port 130 is located on the other side of the porous structure 110; the cover plate 200 is arranged on one side of the substrate 100; the heating component 300 is arranged on the other side of the substrate 100, and the heating component 300 is used to heat the substrate 100; the temperature measuring component 400 is arranged on the same side of the heating component 300, and is used to measure the temperature of the substrate 100 in real time.

[0036] The micro gas chromatograph exhaled breath molecule injection MEMS chip provided in the embodiment of the present application is manufactured by manufacturing a porous structure 110 on a substrate 100, and setting an adsorption material in the pore walls of the porous structure 110, using the adsorption material to adsorb the gas, and then using a cover plate 200 to connect with the substrate 100 to achieve sealing.

[0037] In practical applications, after the gas enters the substrate 100 from the injection port 120, it can flow through the porous structure 110 and flow out from the sample outlet 130. When the gas flows through the porous structure 110, the adsorption material arranged on the pore wall of the porous structure 110 can adsorb the gas. During desorption, the substrate 100 is heated by the heating component 300, so that the gas can be desorbed from the adsorption material and flow out from the sample outlet 130.

[0038] In the micro gas chromatograph exhaled breath molecule sampling MEMS chip provided in the embodiment of the present application, a porous structure 110 is made on a substrate 100, and an adsorption material is arranged in the pore wall of the porous structure 110, and the adsorption material can be used to adsorb gas molecules.

[0039] In practical applications, after the gas molecules enter the substrate 100 from the injection port 120, they can flow through the porous structure 110 and flow out from the sample outlet 130. When the gas molecules flow through the porous structure 110, the adsorption material disposed on the pore wall of the porous structure 110 can adsorb the gas molecules. During thermal desorption, the substrate 100 is heated by the heating component 300, so that the gas molecules can be desorbed from the adsorption material and flow out from the sample outlet 130.

[0040] In the embodiment of the present application, a porous structure 110 is provided in the substrate 100, and an adsorbent material is provided on the pore wall of the porous structure 110 to achieve gas adsorption and desorption. The desorption device is composed of the substrate 100 and the cover plate 200 and other structures, so as to realize the chip design of the traditional desorber, which is conducive to reducing the volume of the micro gas chromatograph exhaled molecule injection MEMS chip, thereby helping to achieve the miniaturization of the micro gas chromatograph exhaled molecule injection MEMS chip. At the same time, the provision of the porous structure 110 increases the specific surface area and improves the adsorption capacity of the micro gas chromatograph exhaled molecule injection MEMS chip for gas molecules. That is to say, under the premise of the same gas molecule adsorption amount, the present embodiment can effectively reduce the volume of the substrate 100, thereby further reducing the volume of the micro gas chromatograph exhaled molecule injection MEMS chip. In addition, by reducing the volume of the substrate 100, the heat transfer efficiency can be accelerated, so that the heat generated by the heating component 300 can be quickly transferred to each position of the porous structure 110, which can improve the thermal desorption efficiency and also help to reduce the heating power of the heating component 300.

[0041] In some embodiments of the present application, the porous structure 110 is disposed close to one of the end surfaces of the substrate 100 , and the porous structure 110 is distributed along the end surface of the substrate 100 , wherein the cover plate 200 abuts against the end surface where the porous structure 110 is disposed.

[0042] In some embodiments of the present application, the adsorbent material is deposited on the pore walls of the porous structure 110 by an atomic layer deposition process. It is worth understanding that atomic layer deposition (ALD) is a thin film deposition technology based on surface self-limiting reaction. Its principle relies on the alternating introduction of two or more precursors into the reaction chamber to form an atomic-level thin film through chemical adsorption and reaction. The key to ALD is that each reaction is self-limiting, that is, each chemical adsorption will saturate the surface and no overreaction will occur, thereby achieving precise control of the film thickness. In this way, the total area of ​​the pore walls of the porous structure 110 can be increased, thereby increasing the coverage area of ​​the adsorbent material to ensure the adsorption effect.

[0043] A sample injection port 120 is provided on one side of the substrate 100, and the sample injection port 120 is used to connect to the outside through a pipeline. In order to facilitate the connection with the outside through the pipeline, it is necessary to ensure that the substrate 100 has a certain thickness. Therefore, in some embodiments of the present application, the thickness of the substrate 100 is 400μm~650μm. In this way, the thickness of the substrate 100 can be effectively controlled, which is conducive to reducing the volume of the micro gas chromatograph exhaled breath molecule injection MEMS chip, and can also facilitate the connection of the external pipeline with the sample injection port 120.

[0044] In a possible implementation, the injection port 120 is used to connect with a commercial capillary. When the thickness of the substrate 100 is less than 400 μm, the commercial capillary cannot be connected; when the thickness of the substrate 100 is greater than 650 μm, the processing difficulty of the substrate 100 will increase.

[0045] In some embodiments of the present application, the substrate 100 is specifically selected as a silicon wafer, the cover plate 200 is specifically selected as a glass sheet, and the cover plate 200 is connected to the substrate 100 through an anodic bonding process. In this way, the cover plate 200 and the substrate 100 can be sealed and connected.

[0046] In some embodiments of the present application, the heating component 300 includes a metal heating electrode, which is disposed on a side of the substrate 100 away from the cover plate 200 to achieve rapid heating for thermal desorption.

[0047] The metal heating electrode may be a heating film or a heating plate to improve heating uniformity.

[0048] In a possible implementation, the material of the metal heating electrode is a metal commonly used in micro-nano processing. Exemplarily, the material of the metal heating electrode includes but is not limited to Au (gold), Pt (platinum), Al (aluminum), etc.

[0049] It should be noted that the metal heating electrode can be manufactured on the substrate 100 by various processing techniques.

[0050] In some embodiments, the metal heating electrode can be fabricated on the substrate 100 by magnetron sputtering, electron beam evaporation, or the like.

[0051] In some embodiments of the present application, the thickness of the heating component 300 is set to 100 nm to 500 nm. In practical applications, the thickness of the heating component 300 can be set to 100 nm, 200 nm, 300 nm, 400 nm or 500 nm as needed.

[0052] In some embodiments of the present application, the micro gas chromatograph exhaled breath molecule sampling MEMS chip further includes a temperature measuring component 400, which is disposed on a side of the substrate 100 away from the cover plate 200, and there is a gap between the temperature measuring component 400 and the heating component 300. Specifically, the temperature measuring component 400 is used to detect the temperature of the substrate 100, thereby realizing real-time temperature measurement of the micro gas chromatograph exhaled breath molecule sampling MEMS chip.

[0053] In some possible implementations, the material of the temperature measuring resistor may be a metal commonly used in micro-nano processing. Exemplarily, the material of the metal heating electrode includes but is not limited to Au (gold), Pt (platinum), Al (aluminum), and the like.

[0054] In the embodiment of the present application, the metal heating electrode can be manufactured on the substrate 100 by various processing techniques. For example, the metal heating electrode can be manufactured on the substrate 100 by magnetron sputtering, electron beam evaporation and the like.

[0055] In some embodiments of the present application, the thickness of the temperature measuring component 400 is set to 100nm-500nm. In practical applications, the thickness of the temperature measuring component 400 can be set to 100nm, 200nm, 300nm, 400nm or 500nm as needed.

[0056] In some embodiments of the present application, at least one of the sample inlet 120 and the sample outlet 130 is obtained by dry etching.

[0057] In a possible implementation manner, the injection port 120 is obtained by dry etching on the substrate 100 .

[0058] In a possible implementation manner, the sample outlet 130 is obtained by dry etching on the substrate 100 .

[0059] In a possible implementation, the sample inlet 120 and the sample outlet 130 are both formed on the substrate 100 by dry etching.

[0060] In some embodiments of the present application, the porous structure 110 is obtained by photolithography. The porous structure 110 has a large specific surface area, which can enable a small desorption chip to achieve a large amount of gas molecule adsorption, which is conducive to reducing the volume of the micro gas chromatograph exhaled molecule injection MEMS chip.

[0061] It is worth understanding that the key to the thermal desorption process is to precisely control the heating temperature and time to ensure that the target substance in the sample can be completely desorbed and enter the analysis process. Thermal desorbers are usually used in conjunction with gas chromatographs (GC) or mass spectrometers (MS) to improve the sensitivity and resolution of detection. At the same time, the large specific surface area allows a small desorption chip to achieve a large number of gas molecules adsorption.

[0062] The present application manufactures a porous structure 110 in a specific area on a silicon wafer by a photolithography process, uniformly deposits gas adsorption materials in the porous structure 110 by atomic layer deposition technology, and then uses an anodic bonding technology to seal the silicon wafer and glass to achieve a desorption chip, thereby achieving chip-based and miniaturized desorption instruments. At the same time, the introduction of the porous structure 110 and atomic layer deposition technology increases the specific surface area.

[0063] On the other hand, an embodiment of the present application discloses a breath molecule analysis gas chromatograph, including the micro gas chromatograph breath molecule injection MEMS chip as described above, which has all the technical effects of the aforementioned chip and will not be repeated here.

[0064] In the description of the present application, it should be understood that the terms "center", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0065] The terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of this application, unless otherwise specified, "plurality" means two or more.

[0066] In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a direct connection, or an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0067] In the description of this specification, specific features, structures, materials or characteristics may be combined in an appropriate manner in any one or more embodiments or examples.

Claims

1. A micro gas chromatograph exhaled breath molecule sampling MEMS chip, characterized in that: include: A substrate having a porous structure, an injection port and an outlet port, wherein the pore wall of the porous structure is provided with an adsorption material, the injection port is located on one side of the porous structure, and the outlet port is located on the other side of the porous structure; A cover plate, disposed on one side of the base plate; A heating component is disposed on the other side of the substrate, and the heating component is used to heat the substrate; The temperature measuring component is arranged on the same side of the heating component, and the temperature measuring component is used to measure the temperature of the substrate in real time.

2. The micro gas chromatograph exhaled breath molecule sampling MEMS chip according to claim 1, characterized in that: The porous structure is arranged close to one of the end faces of the substrate and distributed along the end face plane of the substrate, wherein the cover plate is sealingly connected to the end face provided with the porous structure.

3. The micro gas chromatograph exhaled breath molecule injection MEMS chip according to claim 1 or 2, characterized in that: The adsorption material is deposited on the pore walls of the porous structure by an atomic layer deposition process.

4. The micro gas chromatograph exhaled breath molecule sampling MEMS chip according to claim 1, characterized in that: The thickness of the substrate is 400 μm to 650 μm.

5. The micro gas chromatograph exhaled breath molecule injection MEMS chip according to claim 1, characterized in that: The substrate is a silicon wafer, the cover plate is glass, and the cover plate is connected to the substrate through an anodic bonding process.

6. The micro gas chromatograph exhaled breath molecule injection MEMS chip according to claim 1, characterized in that: The thickness of the heating component is set to 100nm~500nm.

7. The micro gas chromatograph exhaled breath molecule sampling MEMS chip according to claim 1, characterized in that: There is a gap between the temperature measuring component and the heating component.

8. The micro gas chromatograph exhaled breath molecule sampling MEMS chip according to claim 7, characterized in that: The thickness of the temperature measuring component is set to 100nm~500nm.

9. The micro gas chromatograph exhaled breath molecule injection MEMS chip according to claim 1, characterized in that: At least one of the sample inlet and the sample outlet is obtained by dry etching; and / or the porous structure is obtained by photolithography.

10. A breath molecular analysis chromatograph, characterized in that: It comprises the exhaled breath molecule injection MEMS chip for a micro gas chromatograph as claimed in any one of claims 1 to 9.

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