Semiconductor gas sensor based on micromachining technology

Abstract

The utility model discloses a semiconductor gas sensor based on a micromachining technology. The semiconductor gas sensor comprises a first insulating layer; the heating electrode layer is arranged above the first insulating layer; the second insulating layer is arranged above the heating electrode layer; the second insulating layer is provided with an opening structure through which a bonding wire passes; the measuring electrode layer is arranged above the second insulating layer; the gold electrode layer is arranged above the measuring electrode layer; and the sensitive material layer is arranged above the gold electrode layer. Compared with the prior art, the semiconductor gas sensor based on the micromachining technology, provided by the utility model, has the advantages that the sensitive material layer and the heating electrode layer are positioned on the same side, so that the accuracy of an obtained pattern is higher, the consistency of a device and a sensitive material is better, the utilization rate of the sensitive material is higher, the production cost is lower, and the material performance of the heating layer is more stable; and the gas sensor has better performance.

Description

Technical Field

[0001] The utility model relates to the technical field of gas sensors, and more specifically, to a semiconductor gas sensor. Background Art

[0002] Gas sensors are an important detection device that can convert information such as the composition and concentration of gases in the environment into electrical signals, making it easier for personnel, instruments or computer systems to detect and monitor them. Such sensors are widely used in many fields such as environmental protection, industrial safety, healthcare, smart homes, etc.

[0003] One of the most widely used gas sensors currently is the semiconductor gas sensor, which uses screen printing technology on ceramic substrates. This technology creates a sensitive element by printing semiconductor materials, typically metal oxides, onto a ceramic substrate to detect changes in gas concentration and presence. However, this traditional screen printing technology has several significant drawbacks: low precision in printed materials and patterns, resulting in poor sensor consistency; low utilization and high cost of sensitive materials; and unstable heating layer materials, which can affect sensor performance.

[0004] Therefore, how to provide a semiconductor sensor that can make the resulting pattern more accurate, the device more consistent with the sensitive material, the production cost lower, the heating layer material performance more stable, and the gas sensor performance better has become a technical problem that needs to be urgently solved by technicians in this field. Utility Model Content

[0005] In order to solve the above technical problems, the utility model provides a semiconductor gas sensor based on micromachining technology, which can make the obtained pattern more accurate, the consistency between the device and the sensitive material better, the utilization rate of the sensitive material higher, the production cost lower, the performance of the heating layer material more stable, and the gas sensor performance better.

[0006] The technical application provided by this utility model is as follows:

[0007] The utility model provides a semiconductor gas sensor based on micromachining technology, comprising: a first insulating layer; a heating electrode layer arranged above the first insulating layer; a second insulating layer arranged above the heating electrode layer, the second insulating layer being provided with an opening structure for a welding wire to pass through; a measuring electrode layer arranged above the second insulating layer; a gold electrode layer arranged above the measuring electrode layer; and a sensitive material layer arranged above the gold electrode layer.

[0008] Furthermore, in a preferred embodiment of the present invention, the first insulating layer is specifically a silicon oxide insulating layer film.

[0009] Furthermore, in a preferred embodiment of the present invention, the silicon oxide insulating layer film is specifically: a silicon oxide insulating layer film made by a high-temperature oxygen-rich sintering process or a vapor deposition process.

[0010] Furthermore, in a preferred embodiment of the present invention, the heating electrode layer is specifically any one of a platinum micro heater film, a polysilicon semiconductor heater film or a ruthenium oxide semiconductor heater film.

[0011] Furthermore, in a preferred embodiment of the present invention, the heating electrode layer is specifically a heater film manufactured by any one of a magnetron sputtering process, an electron beam deposition process or an ALD process.

[0012] Furthermore, in a preferred embodiment of the present invention, the second insulating layer is specifically a silicon nitride insulating layer film.

[0013] Furthermore, in a preferred embodiment of the present invention, the silicon nitride insulating layer film is specifically: a silicon nitride insulating layer film made by a magnetron sputtering process or a vapor deposition process.

[0014] Furthermore, in a preferred embodiment of the present invention, the measuring electrode layer is specifically a titanium gold interdigital measuring electrode layer or a tantalum nitride interdigital measuring electrode layer.

[0015] Furthermore, in a preferred embodiment of the present invention, the thickness of the first insulating layer is 70 to 90 nm; and / or the thickness of the heating electrode layer is 110 to 130 nm; and / or the thickness of the second insulating layer is 90 to 110 nm.

[0016] Furthermore, in a preferred embodiment of the present invention, the thickness of the measuring electrode layer is 50 to 70 nm; and / or the thickness of the gold electrode layer is 110 to 130 nm; and / or the thickness of the sensitive material layer is 90 to 110 nm.

[0017] In summary, the present invention provides a semiconductor gas sensor based on micromachining technology, comprising: a first insulating layer; a heating electrode layer disposed above the first insulating layer; a second insulating layer disposed above the heating electrode layer, the second insulating layer being provided with an opening structure for the welding wire to pass through; a measuring electrode layer disposed above the second insulating layer; a gold electrode layer disposed above the measuring electrode layer; and a sensitive material layer disposed above the gold electrode layer. The heating electrode layer and the sensitive material layer are located on the same side, and the heating source can directly and quickly heat the sensitive material, reducing energy loss. Furthermore, since the heating layer material is wrapped and not directly exposed to the external environment, the performance of the heating layer material is more stable. The present invention not only improves heating efficiency and reduces the energy consumption required to heat the sensitive material, but also, since the heating is faster and more uniform, it can more effectively respond to the target gas, thereby improving the utilization rate of the sensitive material. Furthermore, micromachining technology enables higher patterning accuracy of the sensitive material and better device consistency, reducing material waste that may occur during the manufacturing process, and indirectly improving the effective utilization rate of the sensitive material. In summary, compared with the existing technology, the semiconductor gas sensor based on micromachining technology provided by the utility model has a sensitive material layer and a heating electrode layer located on the same side, the resulting pattern has higher precision, the consistency between the device and the sensitive material is better, the utilization rate of the sensitive material is higher, the production cost is lower, the performance of the heating layer material is more stable, and the gas sensor performance is better. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the embodiments of the present invention or the technical applications in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0019] Figure 1 A schematic diagram of a semiconductor gas sensor structure based on micromachining technology provided by an embodiment of the present invention;

[0020] Figure 2 A schematic diagram of a measuring electrode provided in an embodiment of the present utility model;

[0021] Figure 3 This is a power stability test diagram of a traditional sensor structure and a sensor structure based on micromachining technology provided by an embodiment of the present utility model. DETAILED DESCRIPTION

[0022] In order to enable those skilled in the art to better understand the technical application of the present invention, the technical application of the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings of the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without making creative efforts shall fall within the scope of protection of the present invention.

[0023] It should be noted that when an element is referred to as being “fixed on” or “set on” another element, it can be directly on the other element or indirectly set on the other element; when an element is referred to as being “connected to” another element, it can be directly connected to the other element or indirectly connected to the other element.

[0024] It should be understood that the terms "length", "width", "up", "down", "front", "back", "first", "second", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing the present invention 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 operate in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0025] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of the technical features being referred to. Thus, a feature specified as "first" or "second" may explicitly or implicitly include one or more of such features. In the description of this utility model, "plurality" or "several" means two or more, unless otherwise specifically defined.

[0026] It should be noted that the structures, proportions, sizes, etc. depicted in the drawings of this specification are only used to match the contents disclosed in the specification so as to facilitate understanding and reading by people familiar with this technology. They are not intended to limit the conditions under which the present invention can be implemented, and therefore have no substantive technical significance. Any structural modifications, changes in proportional relationships, or adjustments in size should still fall within the scope of the technical contents disclosed in this utility model without affecting the efficacy and objectives that can be achieved by the present utility model.

[0027] like Figures 1 to 3As shown, the utility model provided by the embodiment of the present invention provides a semiconductor gas sensor based on micromachining technology, including: the utility model provides a semiconductor gas sensor based on micromachining technology, including: a first insulating layer 1; a heating electrode layer 2 arranged above the first insulating layer 1; a second insulating layer 3 arranged above the heating electrode layer 2, and the second insulating layer 3 is provided with an opening structure for the welding wire to pass through; a measuring electrode layer 4 arranged above the second insulating layer 3; a gold electrode layer 5 arranged above the measuring electrode layer 4; and a sensitive material layer 6 arranged above the gold electrode layer 5.

[0028] Specifically, in the embodiment of the present invention, the first insulating layer 1 is a silicon oxide insulating layer, and the thickness of the first insulating layer 1 is 70-90 nm.

[0029] Among them, it is more preferred that the silicon oxide insulating layer has a film thickness of 80 nm.

[0030] Specifically, in the embodiment of the present invention, the silicon oxide insulating layer film is specifically: a silicon oxide insulating layer film made by a high-temperature oxygen-rich sintering process or a vapor deposition process.

[0031] Among them, the high-temperature oxygen-rich sintering process can improve the density and stability of the film; the low-temperature process in vapor deposition technology can adapt to more types of substrates, thereby ensuring the stability of the gas sensor.

[0032] The first insulating layer 1 isolates the silicon wafer from the heater electrode layer 2, which conducts electricity. Silicon oxide prevents contact and conduction between the two. When the silicon wafer is placed in a high-temperature, pure oxygen environment for 4 hours, it interacts with the oxygen, forming silicon oxide on its surface. The first insulating layer 1 isolates the silicon wafer from contact and conduction via the silicon oxide insulating film, improving the stability and service life of the heater electrode layer. It prevents direct contact between the heater electrode layer and the external environment, and reduces performance degradation due to factors such as oxidation. This allows the gas sensor to maintain higher reliability and a longer service life in complex environments, while ensuring the consistency and accuracy of detection results.

[0033] Specifically, in the embodiment of the present invention, the heating electrode layer 2 is any one of a platinum micro heater film, a polysilicon semiconductor heater film or a ruthenium oxide semiconductor heater film.

[0034] Specifically, in the embodiment of the present invention, the heating electrode layer 2 is specifically: a heater film made by any one of a magnetron sputtering process, an electron beam deposition process or an ALD process.

[0035] Among them, by adopting a variety of thin film deposition technologies such as magnetron sputtering, electron beam deposition and atomic layer deposition, the utility model greatly optimizes the performance of the gas sensor. The highly uniform thin film deposition provided by magnetron sputtering ensures the uniform distribution of heater materials such as polysilicon or RuO2 on the substrate, thereby improving the heating efficiency and consistency of the sensor. Electron beam deposition, due to its high purity and density, enhances the quality of the film, reduces defects, and further improves the reliability and stability of the sensor. The introduction of ALD technology allows for precise control of film thickness layer by layer, achieving uniform coverage even in complex three-dimensional structures, ensuring the performance consistency of the sensor on a microscale. In summary, the selection and application of these advanced thin film deposition technologies have significantly optimized the film quality and manufacturing accuracy of gas sensors, thereby improving the overall detection performance and service life.

[0036] Specifically, in the embodiment of the present invention, the thickness of the heating electrode layer 2 is 110-130 nm.

[0037] More preferably, the thickness of the heating electrode layer is 120 nm.

[0038] Among them, the present invention ensures the stability of the heating performance of the gas sensor during long-term use by selecting polysilicon, ruthenium oxide or platinum as the heater material. The polysilicon heater provides a uniform heating effect and maintains structural integrity, the ruthenium oxide heater generates high heat output at low voltage and has good chemical stability, and the platinum heater operates stably in various environments with its excellent chemical and thermal stability, reducing maintenance requirements and extending service life, thereby comprehensively improving the reliability and accuracy of the sensor. In summary, by using polysilicon, ruthenium oxide or platinum as the heater material, the gas sensor of the present invention is able to maintain the stability of its heating performance during long-term use, thereby ensuring the reliability and accuracy of the sensor throughout its life cycle, and optimizing the applicability and durability of the sensor under various environmental conditions.

[0039] Specifically, in the embodiment of the present invention, the second insulating layer 3 is a silicon nitride insulating thin film layer.

[0040] The second insulating layer 3 is etched with an ICP etcher to form openings, thereby ensuring good contact between the welding wire and the heating electrode layer while avoiding damage to surrounding materials.

[0041] Specifically, in the embodiment of the present invention, the silicon nitride insulating layer film is specifically: a silicon nitride insulating layer film made by a magnetron sputtering process or a vapor deposition process.

[0042] Among them, the utility model uses magnetron sputtering to coat a SiN insulating layer with a thickness of only nm on the heating electrode layer 2, and the heating electrode layer 2 is covered by the first insulating layer 1 below and the second insulating layer 3 above, effectively isolating the direct contact with the external environment. At the same time, due to the small distance between the heating electrode layer 2 and the measuring electrode layer 4, the heating electrode layer 2 has a faster heating rate, thereby optimizing the performance of the gas sensor.

[0043] Specifically, in the embodiment of the present invention, the thickness of the second insulating layer 3 is 90-110 nm.

[0044] More preferably, the thickness of the silicon nitride insulating layer is 100 nm.

[0045] Specifically, in the embodiment of the present invention, the measuring electrode layer 4 is a titanium gold interdigital measuring electrode layer or a tantalum nitride interdigital measuring electrode layer.

[0046] In this embodiment of the present invention, the processes involved in forming the measuring electrode layer 4 include: a smearing process, a laser direct writing process, a manual development process, an electron beam sputtering process, and an NMP stripping process. During the thin film deposition stage, electron beam sputtering is used to deposit the metal material; during the patterning stage, laser direct writing is used to directly form the pattern, smearing is used to apply the photoresist, manual development is used to develop the pattern, and NMP stripping is used to remove material from unpatterned areas.

[0047] Among them, the coating process can make the coating evenly distributed, which helps to form a flat and uniformly thick electrode layer, thereby improving the consistency and stability of the sensor response; laser direct writing technology can achieve high-precision patterning, which is suitable for the production of electrodes requiring fine structures and high-resolution graphics, which is beneficial to improving the sensitivity and detection accuracy of the sensor; the manual development process is traditional but highly flexible, suitable for small batch or special shape designs, and can meet the needs of specific sensor designs; the electron beam sputtering process can provide high-quality thin film deposition, ensuring the purity and density of the electrode material, and helping to improve the reliability and long-term stability of the sensor; NMP stripping technology can maintain good edge clarity when removing excess material, which is suitable for application scenarios requiring fine edge control, and helps to improve the accuracy and reliability of the measuring electrode layer, thereby improving the performance of the gas sensor.

[0048] The measuring electrode layer 4 directly measures the resistance or current change of the gas-sensitive material. Therefore, a dense, uniform, and consistent measuring electrode layer 4 effectively reduces the resistance of the sensitive material layer 6 and allows for rapid and efficient detection of resistance or current changes in the sensitive material layer 6. Using a process involving coating, laser direct writing, manual development, electron beam sputtering, and NMP stripping, the insulating layer is coated with interdigital electrodes of TaN and TiAu. The resulting micromachining process achieves a higher density and greater dimensional uniformity of interdigital electrodes, achieving a minimum interdigital distance of several micrometers.

[0049] The interdigital electrodes of the measuring electrode layer 4 are spaced several micrometers apart. This dense, uniform, and consistent structure, compared to traditional structures, allows for rapid and effective detection of resistance changes in the sensitive material layer. Because resistance changes reflect immediate changes in gas composition or concentration, capturing these changes more quickly and accurately enables the sensor to provide reliable detection data in real time, making it suitable for applications requiring immediate response. Therefore, the dense and uniform interdigital electrode structure improves the response speed and detection accuracy of gas sensors.

[0050] Specifically, in the embodiment of the present invention, the thickness of the measuring electrode layer 4 is 50-70 nm.

[0051] More preferably, the thickness of the titanium-gold interdigital measurement electrode layer is 60 nm.

[0052] Specifically, in the embodiment of the present invention, the thickness of the gold electrode layer 5 is 110-130 nm.

[0053] More preferably, the thickness of the gold electrode layer 5 is 120 nm.

[0054] Specifically, in the embodiment of the present invention, the gold electrode layer 5 is coated on the measuring electrode layer 4 by printing, and is etched to keep the shape and size consistent with the measuring electrode layer 4.

[0055] Specifically, in the embodiment of the present invention, the thickness of the sensitive material layer 6 is 90-110 nm.

[0056] More preferably, the thickness of the sensitive material layer 6 is 100 um.

[0057] Specifically, in the embodiment of the present invention, the sensitive material layer 6 is printed on the sensor. In the embodiment of the present invention, the sensitive material of the sensitive material layer 6 is specifically a tin oxide semiconductor.

[0058] After the sensor is manufactured, the sensitive material layer 6 is printed on the sensor, and finally the corresponding welding is completed, thus completing the manufacture of the entire gas sensor.

[0059] The solution involved in the embodiment of the utility model uses screen printing technology to achieve uniform distribution of sensitive materials, improve material utilization, and reduce production costs. In addition, by combining micromachining and printing processes, the response speed and sensitivity of the sensor are improved, enhancing the detection performance of the sensor.

[0060] As can be seen from the above, the utility model uses a micro-machined silicon oxide insulating layer film to isolate the heating electrode layer, prevent the heating electrode layer from being conductive, and protect the heating electrode layer from direct contact with the air; uses a micro-machined platinum micro heater film to provide high temperature to maintain optimal sensitivity; uses a micro-machined silicon nitride insulating layer film to isolate the heating electrode layer and the measuring electrode layer to prevent direct contact between the two; uses a micro-machined titanium-gold interdigitated measuring electrode layer to quickly and effectively detect resistance changes; and uses a gold electrode layer that combines micro-machining technology and printing technology to accurately test current or resistance changes.

[0061] The present invention provides a semiconductor gas sensor based on micromachining technology. The sensitive material layer and the heating electrode layer are located on the same side. The pattern obtained through micromachining technology is more precise and the consistency between the device and the sensitive material is better. Through high-precision micromachining technology, the sensor can provide high-resolution gas concentration detection results, improving detection accuracy and sensitivity. The optimized heater design and the use of highly conductive materials enable the sensor to quickly respond to changes in gas concentration and shorten response time. The multi-layer structure and high-quality materials enable the sensor to maintain its initial performance during long-term use, reducing the need for maintenance and calibration. By combining high-precision micromachining with traditional screen printing processes, the utilization rate of sensitive materials is increased and production costs are reduced. The heating layer material is completely enclosed and not exposed to the air, resulting in more stable performance and faster heating, improving the performance of semiconductor gas sensors. In summary, the gas sensor of the present invention not only operates reliably in a variety of complex environments, but also has high application value due to its high-precision detection, rapid response, long-term stability, and cost-effectiveness.

[0062] More specifically, the sensor structure currently widely used in the market is the indirectly heated structure, the most common of which is the planar indirectly heated structure. This means that the heating layer material is located on one side of the ceramic plate, while the heating electrode and measuring electrode are located on the other side of the ceramic plate. However, this structure results in the heating layer heating the sensitive material slowly after the sensor is energized. Moreover, the heating layer material is exposed to air, which may cause instability in the heating layer material over long periods of use, thereby affecting the sensor's accurate detection of gas composition and concentration. In addition, the existing measuring electrode is large in size, which adversely affects the resistance of semiconductor gas sensors.

[0063] Based on the problems of the existing technology, the gas sensor structure provided by the utility model has the following three advantages: the sensitive material and the heating electrode are located on the same side, and the pattern accuracy is improved through micromachining technology, so that the consistency between the device and the sensitive material is better; the utilization rate of the sensitive material is increased, thereby reducing the production cost; the heating layer material is completely wrapped and not directly exposed to the air, so the performance of the heating layer material is more stable, and the sensitive material can be heated more quickly, thereby improving the overall performance of the semiconductor gas sensor.

[0064] The embodiment of the present utility model proposes a solution for manufacturing a semiconductor gas sensor structure based on micromachining technology. The purpose is to improve the accuracy, product consistency and stability of sensor production by introducing high-precision micromachining technology and combining it with traditional screen printing technology, while significantly reducing production costs.

[0065] To elaborate more specifically, the present invention provides a novel semiconductor resistor-type gas sensor structure and its micro-machining manufacturing process scheme. The resulting semiconductor gas sensor has a simple structure, stable performance, and low production cost, and has high application value in the field of flammable, explosive, toxic and harmful gas detection. In order to achieve the above-mentioned purpose, the novel structural technical scheme of the present invention is completed by combining micro-machining technology with screen printing technology. The first insulating layer 1 designed in the embodiment of the present invention is a silicon oxide insulating layer film using micro-machining technology. The insulating layer has a thickness of 80nm and is located at the bottom. Its main function is to isolate the heating electrode, prevent the heating electrode from being turned on, and protect the heating electrode from direct contact with the air. The insulating dielectric layer can be an insulating material such as silicon oxide, and the film can be processed using a high-temperature oxygen-rich sintering process or a vapor deposition process.

[0066] The heating electrode layer 2 designed in the embodiment of the present invention is a platinum micro-heater film using micro-machining technology, with a thickness of preferably 120 nm. It is located on the first insulating layer 1, and its main function is to provide high temperature for the sensitive material to maintain optimal sensitivity. The micro-heater material can also be polycrystalline silicon or ruthenium oxide semiconductor heater, and the film can be made by any one of the processes including magnetron sputtering process, electron beam deposition process or atomic layer deposition process.

[0067] The second insulating layer 3 designed in this embodiment of the utility model is a micro-machined silicon nitride insulating film, preferably 100 nm thick. It is located above the heater electrode layer 2 and primarily isolates the heater electrode layer 2 from the measuring electrode layer 4, preventing direct contact between the two. Furthermore, a hole must be formed in this insulating layer to allow direct contact between the bonding wire and the heater electrode. This insulating film can be fabricated using magnetron sputtering or vapor deposition, and an ICP etcher can be used to etch the hole.

[0068] Furthermore, the measuring electrode layer 4 designed in this embodiment of the present invention utilizes titanium-gold interdigitated measuring electrodes fabricated using micromachining technology. The thickness is preferably 60 nm, and the interdigitated electrodes are spaced several microns apart. This dense, uniform, and consistent structure is superior to traditional structures. Its primary function is to quickly and effectively detect changes in the resistance of sensitive materials. These measuring electrodes, located above the second insulating layer 3 and made of tantalum nitride, are fabricated using a combination of coating, laser direct writing, manual development, electron beam sputtering, and NMP stripping processes.

[0069] Furthermore, the gold electrode layer 5 designed in this embodiment of the present invention is manufactured using a combination of micromachining and printing technologies. Its thickness is preferably 120 nm. Located above the measuring electrode layer 4, its primary function is to accurately measure changes in current or resistance of sensitive materials. The gold electrode layer 5 is applied to the measuring electrode layer 4 by printing and then etched to maintain its shape and size identical to that of the measuring electrode layer 4.

[0070] Furthermore, the sensitive material layer 6 designed in this embodiment of the present invention is preferably 100 microns thick and is located above the gold electrode layer 5. Its primary function is to measure gas concentration and composition. After the sensor is fabricated, the sensitive material can be printed onto the sensor and then soldered to complete the entire gas sensor.

[0071] To sum up, the technical solution involved in the embodiment of the present invention designs a new planar indirect heating gas sensor, which is suitable for various semiconductor gas sensors, has important application value in gas detection in complex environments, and has important commercial value for the practical application of semiconductor gas sensors.

[0072] The semiconductor gas sensor based on micromachining technology involved in the embodiment of the present invention uses tin oxide semiconductor as the sensitive material. The sensitive material of the same thickness is printed on the micromachining sensor provided by this solution and the traditional structure sensor, and the power-on stability test of the two structures is carried out. The specific results are shown in the attached Figure 3 As shown, the test results show that compared with the traditional structure in the existing technology, when the sensitive material is the same, the air resistance value of the micro-machined sensor structure is lower than that of the traditional structure sensor, and the power-on stabilization time is shorter, and it can reach stability within half an hour, which optimizes the use efficiency of the sensor, indicating that this structure has better performance for semiconductor gas sensors.

[0073] The above description of the disclosed embodiments will enable one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be readily apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention is not limited to the embodiments shown herein but is intended to conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A semiconductor gas sensor based on micromachining technology, characterized in that: include: a first insulating layer (1); a heating electrode layer (2) disposed above the first insulating layer (1); a second insulating layer (3) disposed above the heating electrode layer (2), the second insulating layer (3) being provided with an opening structure for the welding wire to pass through; a measuring electrode layer (4) disposed above the second insulating layer (3); a gold electrode layer (5) disposed above the measuring electrode layer (4); A sensitive material layer (6) is arranged above the gold electrode layer (5).

2. The semiconductor gas sensor based on micromachining technology according to claim 1, characterized in that: The first insulating layer (1) is specifically a silicon oxide insulating layer film.

3. The semiconductor gas sensor based on micromachining technology according to claim 2, characterized in that: The silicon oxide insulating layer film is specifically: a silicon oxide insulating layer film made by a high-temperature oxygen-rich sintering process or a vapor deposition process.

4. The semiconductor gas sensor based on micromachining technology according to claim 1, characterized in that: The heating electrode layer (2) is specifically any one of a platinum micro heater film, a polysilicon semiconductor heater film or a ruthenium oxide semiconductor heater film.

5. The semiconductor gas sensor based on micromachining technology according to claim 4, characterized in that: The heating electrode layer (2) is specifically a heater film made by any one of a magnetron sputtering process, an electron beam deposition process or an ALD process.

6. The semiconductor gas sensor based on micromachining technology according to claim 1, characterized in that: The second insulating layer (3) is specifically a silicon nitride insulating layer film.

7. The semiconductor gas sensor based on micromachining technology according to claim 6, characterized in that: The silicon nitride insulating layer film is specifically: a silicon nitride insulating layer film made by a magnetron sputtering process or a vapor deposition process.

8. The semiconductor gas sensor based on micromachining technology according to claim 1, characterized in that: The measuring electrode layer (4) is specifically a titanium-gold interdigitated measuring electrode layer or a tantalum nitride interdigitated measuring electrode layer.

9. The semiconductor gas sensor based on micromachining technology according to claim 1, characterized in that: The thickness of the first insulating layer (1) is 70 to 90 nm; and / or the thickness of the heating electrode layer (2) is 110 to 130 nm; and / or the thickness of the second insulating layer (3) is 90 to 110 nm.

10. The semiconductor gas sensor based on micromachining technology according to claim 9, characterized in that: The thickness of the measuring electrode layer (4) is 50 to 70 nm; and / or the thickness of the gold electrode layer (5) is 110 to 130 nm; and / or the thickness of the sensitive material layer (6) is 90 to 110 nm.

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