On-chip miniature ionization vacuum sensor

Abstract

The utility model provides an on-chip miniature ionization vacuum sensor, comprising: an electron emission and collection structure comprising an insulating substrate, a penetrating electrode pair formed on the substrate, an electron emitter located on the substrate and connected with the penetrating electrode pair, and a first collector closely arranged around the periphery of the substrate; the insulating spacer layer is located on the side, provided with the electron emitter, of the electron emission and collection structure and surrounds the electron emitter, and a penetrating cavity is formed between the electron emission and collection structure and the second collector; and the second collector is positioned on one side, far away from the electron emission and collection structure, of the insulating spacer layer and is provided with a through hole communicated with the penetrating cavity. The on-chip miniature ionization vacuum sensor is small in size, simple in structure, wide in applicable vacuum range and low in energy consumption cost.

Description

Technical Field

[0001] The utility model relates to the technical field of vacuum devices, in particular to an on-chip micro ionization vacuum sensor for measuring vacuum degree. Background Art

[0002] Accurate and effective vacuum measurement is an indispensable key technology in all vacuum-related fields. Common vacuum measurement devices include compression vacuum sensors, thin film vacuum sensors, thermocouple vacuum sensors, resistance vacuum sensors and ionization vacuum sensors. These different types of vacuum sensors correspond to different measurement ranges. However, only ionization vacuum sensors can cover 10 -1 The vacuum range below Pa plays an important role in fields requiring high vacuum or ultra-high vacuum, such as aerospace, military, and semiconductor industries.

[0003] Traditional ionization vacuum sensors fabricated through mechanical processing typically use a hot cathode. This type of ionization vacuum sensor suffers from disadvantages such as large size, high mass, high energy consumption, and severe outgassing. This is contrary to the trend toward miniaturization, on-chip integration, and integration of vacuum electronic devices, limiting their application. Currently, on-chip micro-ionization vacuum gauges that use high-voltage discharge ionization exist, but these are limited by factors such as stability and lifespan, exhibiting problems such as narrow detection range, low stability, high operating voltage, and short lifespan. Chinese invention patent application number 2019111328116, entitled "An On-Chip Micro-Ionization Vacuum Sensor and Its Manufacturing Method," discloses a five-layer on-chip micro-ionization vacuum sensor. However, this sensor also suffers from a complex structure and a narrow vacuum measurement range. In other words, the prior art still lacks a reliable solution for on-chip micro-ionization vacuum gauges with a wide vacuum measurement range.

[0004] Therefore, in order to adapt to the miniaturization of devices, there is an urgent need for an on-chip micro ionization vacuum sensor with small size, simple structure, wide applicable vacuum range and low energy consumption cost. Utility Model Content

[0005] In view of this, an embodiment of the present invention provides an on-chip micro ionization vacuum sensor that can realize on-chip wafer processing, which not only greatly reduces the volume and energy consumption, but also the prepared vacuum device has the advantages of simple structure and wide vacuum measurement range.

[0006] One aspect of the present invention provides an on-chip micro ionization vacuum sensor, comprising:

[0007] An electron emission and collection structure comprises an insulating substrate, a pair of through electrodes formed on the substrate, an electron emitter located on the substrate and connected to the pair of through electrodes, and a first collector arranged closely around the periphery of the substrate; the pair of through electrodes are used to be applied with a driving voltage to drive the electron emitter to emit electrons; the first collector is used to be applied with a positive voltage to collect the electrons emitted by the electron emitter, or is used to be applied with a negative voltage to collect ions;

[0008] An insulating spacer layer is located on the side of the electron emission and collection structure with the electron emitter, and forms a through cavity between the electron emission and collection structure and a second collector around the electron emitter;

[0009] The second collector is located on the side of the insulating spacer layer away from the electron emission and collection structure, and is used to be applied with a negative voltage to capture ions reaching the second collector through the through cavity, or is used to be applied with a positive voltage to collect electrons; the second collector has a single or multiple through holes;

[0010] The on-chip micro ionization vacuum sensor is used to determine the vacuum degree based on the electrons and ions collected by the first collector and the second collector respectively.

[0011] In some embodiments of the present application, the insulating substrate is a through silicon substrate or a through glass substrate.

[0012] In some embodiments of the present application, the insulating spacer layer is a glass layer, a ceramic layer, a sapphire layer, a silicon carbide layer or an intrinsic silicon layer.

[0013] In some embodiments of the present application, the second collector is a conductive silicon layer or a conductive metal layer.

[0014] In some embodiments of the present application, the electron emission and collection structure further comprises an insulating layer arranged closely around the first collector, so that all surfaces of the electron emitter and the first collector are exposed to the through cavity.

[0015] In some embodiments of the present application, the electron emitter is a thermal electron emitter.

[0016] In some embodiments of the present application, the electron emitter is in a filamentous or sheet shape.

[0017] In some embodiments of the present application, the electron emitter is arched towards the direction away from the substrate to form a heat dissipation gap between the electron emitter and the substrate; or

[0018] A groove is arranged on the insulating substrate between the pair of through electrodes, and the electron emitter is at least partially suspended above the groove.

[0019] In some embodiments of the utility model, the hot electron emitter is a conductive metal wire coated with a hot emission film prepared from a hot emission material.

[0020] In some embodiments of the utility model, the overall size of the ionization vacuum sensor is 1*1*1mm-20*20*5mm, the height of the first collector electrode is 0.3mm-3mm, the height of the insulating spacer layer is 0.5-4mm, and the height of the second collector electrode is 0.1-0.3mm.

[0021] The on-chip micro ionization vacuum sensor provided by the utility model is compatible with micro-nano processing technology and semiconductor technology, and the ionization vacuum sensor with a three-layer structure is prepared by bonding and packaging the electron emission and collection structure, the insulating spacer layer and the second collector electrode, and the vacuum device has the advantages of small size, light weight, low cost and wide vacuum measurement range.

[0022] The additional advantages, objects, and features of the utility model will be partially set forth in the following description, and will become apparent to those skilled in the art upon reading the following detailed description, or can be learned from practice of the utility model. The objects and other advantages of the utility model can be realized and obtained by the structure specifically pointed out in the specification and the drawings.

[0023] Those skilled in the art will understand that the objects and advantages realized by the utility model are not limited to the above specific description, and the above and other objects realized by the utility model will be more clearly understood according to the following detailed description. BRIEF DESCRIPTION OF DRAWINGS

[0024] The drawings described herein are used to provide further understanding of the utility model, constitute a part of the application, and do not constitute a limitation to the utility model. The components in the drawings are not drawn to scale, but only to show the principles of the utility model. In order to facilitate the illustration and description of some parts of the utility model, the corresponding parts in the drawings can be enlarged, that is, they can become larger than other components in the exemplary device actually manufactured according to the utility model. In the drawings:

[0025] Figure 1 It is a structure schematic view of the on-chip micro ionization vacuum sensor in an embodiment of the utility model.

[0026] Figure 2 It is a schematic view of the insulating spacer layer in an embodiment of the utility model.

[0027] Figure 3 It is a schematic view of the second collector electrode in an embodiment of the utility model.

[0028] Figure 4Schematic diagram of the electron emission and collection structure of an on-chip micro ionization vacuum sensor in one embodiment of the present invention.

[0029] Figure 5 The figure is a schematic diagram of the working principle of the on-chip micro ionization vacuum sensor in one embodiment of the present invention.

[0030] Figure 6 Schematic diagram comparing on-chip micro ionization vacuum sensors with three-layer structures and five-layer structures in one embodiment of the present invention.

[0031] Figure 7 This is a scatter plot showing how the ratio of ion current to electron current varies with the ambient pressure of the on-chip micro ionization vacuum sensor in one embodiment of the present invention.

[0032] Figure 8 Schematic diagram of a bonding method for a single on-chip micro ionization vacuum sensor in one embodiment of the present invention.

[0033] Figure 9 The figure is a flow chart of a bonding method for a single on-chip micro ionization vacuum sensor in one embodiment of the present invention.

[0034] Figure 10 This is a schematic diagram of batch preparation of on-chip micro ionization vacuum sensors in one embodiment of the present invention.

[0035] Figure 11 The figure is a schematic diagram of the process of batch preparing on-chip micro ionization vacuum sensors in one embodiment of the present invention. DETAILED DESCRIPTION

[0036] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the embodiments and the accompanying drawings. Here, the schematic embodiments of the present invention and their description are used to explain the present invention, but are not intended to limit the present invention.

[0037] It should also be noted here that, in order to avoid obscuring the present invention due to unnecessary details, only structures and / or processing steps closely related to the solution according to the present invention are shown in the accompanying drawings, while other details that are not closely related to the present invention are omitted.

[0038] It should be emphasized that the term "include / comprises" when used herein refers to the existence of features, elements, steps or components, but does not exclude the existence or addition of one or more other features, elements, steps or components.

[0039] It should also be noted that, unless otherwise specified, the term "connection" herein may refer not only to a direct connection but also to an indirect connection involving an intermediate.

[0040] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. In the accompanying drawings, the same reference numerals represent the same or similar components, or the same or similar steps.

[0041] Ionization vacuum sensors are mainly used to measure the vacuum degree of the environment they are in. Their measurement principle is as follows: electrons with a certain energy collide with gas molecules in the environment to be measured, causing them to ionize into ions. The second collector then collects the ions to generate an ion current, and the first collector collects the electrons to generate an electron current (or the second collector collects the electrons to generate an electron current, and the first collector collects the ions to generate an ion current). Within a certain pressure range, the ratio of the ion current to the electron current has a certain linear relationship with the gas pressure of the environment to be measured, thereby inferring the vacuum degree of the environment to be measured. Because the structure of current on-chip micro vacuum measurement devices is relatively complex and the measurement range is relatively narrow, based on this, the embodiments of the present application provide an on-chip micro ionization vacuum sensor with a small size, simple structure, and a wide applicable vacuum range.

[0042] In some embodiments of the present invention, Figure 1 The schematic diagram of the structure of the on-chip micro ionization vacuum sensor is shown in Figure 2. Figure 1 As shown in FIG, the structure of the on-chip micro ionization vacuum sensor includes:

[0043] The electron emission and collection structure 110 includes an insulating substrate 113, a pair of through-electrodes 111 (including a first electrode 1111 and a second electrode 1112) formed on the insulating substrate 113, an electron emitter 115 located on the insulating substrate 113 and connected to the through-electrode pair 111, and a first collector 117 arranged closely around the outer periphery of the insulating substrate 113. The through-electrode pair 111 is used to be applied with a driving voltage (the driving voltage mentioned in this application is a positive voltage) to drive the electron emitter 115 to emit electrons. The first collector 117 is used to be applied with a positive voltage to collect electrons emitted by the electron emitter 115, or to be applied with a negative voltage to collect ions.

[0044] an insulating spacer layer 130 located on one side of the electron emitting and collecting structure 110 having the electron emitter 115 , the insulating spacer layer 130 surrounding the electron emitter 115 and forming a through cavity 131 between the electron emitting and collecting structure 110 and the second collector 150 ;

[0045] The second collector 150 is located on the side of the insulating spacer layer 130 away from the electron emission and collection structure 110, and the second collector layer 150 has a single or multiple through holes; wherein, the second collector 150 is used to be applied with a negative voltage to capture ions reaching the second collector 150 through the through cavity 131, or to be applied with a positive voltage to collect electrons reaching the second collector 150 through the through cavity 131.

[0046] The electron emission and collection structure 110, the insulating spacer layer 130, and the second collector 150 can be sequentially bonded together through methods such as anodic bonding to form a three-layer on-chip micro-ionization vacuum sensor. In the present invention, the on-chip micro-ionization vacuum sensor formed by the electron emission and collection structure 110, the insulating spacer layer 130, and the second collector 150 is a semi-enclosed chamber that can be used to perform vacuum measurements in a tiny vacuum chamber based on the electrons and ions collected by the first collector 117 and the second collector 150, respectively.

[0047] The electron emission and collection structure 110 is used to emit and collect electrons, or to emit and collect ions. The electron emission and collection structure 110 includes at least one through-electrode pair 111 and a corresponding electron emitter 115, the insulating spacer layer 130 includes at least one through-cavity 131, and the second collector 150 has at least one through-hole 151, and the through-cavity 131 is connected to the through-hole 151 to ensure that gas can flow between the interior of the ionization vacuum sensor and the external environment. For example, Figure 2 As shown, the insulating spacer layer 130 has a through cavity 131; Figure 3 As shown, the number of through holes 151 on the second collector 150 may be 9 and arranged in an array.

[0048] As an example, Figure 4 As shown, in order to facilitate the collection of electrons emitted in various directions by the electron emitter 115 or ions generated by gas ionization, the first collector 117 needs to be arranged around the substrate 113 (that is, the first collector 117 is located around the substrate 113), so that the first collector 117 has a sufficient area to collect most of the electrons or ions emitted by the electron emitter 115. Moreover, the surrounding arrangement also allows the electrons emitted from the electron emitter 115 to have a longer movement path (that is, the electrons emitted by the electron emitter 115 have sufficient movement space), thereby improving the ionization efficiency. In addition, the electron emission and collection structure 110 may also include an insulating layer 118 (such as Figure 4 As shown in (e) and (f) in FIG), the insulating spacer layer 130 can be disposed above the insulating layer 118 so that the entire surface of the electron emitter 115 and the first collector 117 are exposed in the through cavity 131.

[0049] In some embodiments of the present invention, Figure 5As shown, in the on-chip micro-ionization vacuum sensor, a pair of through-electrodes (i.e., first electrode 1111 and second electrode 1112) disposed on substrate 113 are connected to an external voltage so that a driving voltage is applied to excite the connected electron emitter 115 to generate and emit electrons (the first electrode 1111 can be grounded and the second electrode 1112 can be externally biased, or the first electrode 1111 can be externally biased and the second electrode 1112 can be grounded). A first collector 117 is externally biased to a positive voltage (approximately 50 to 300 V) to collect electrons emitted by the electron emitter 115, thereby generating an electron stream. A second collector 150 is externally biased to a negative voltage (i.e., connected to the negative terminal of an external power supply) to collect positive ions (for simplicity, all ions mentioned below refer to positive ions) formed by ionization of gas molecules within the through-cavity 131, thereby generating an ion stream. The negative bias applied to the second collector 150 can be between 0 and -300 V.

[0050] Based on the connection method between the on-chip micro ionization vacuum sensor and the pressure power supply, the working principle of the on-chip micro ionization vacuum sensor is as follows: when the ionization vacuum sensor is working, first, by applying a driving voltage to the first electrode 1111 and the second electrode 1112, the electron emitter 115 is activated to emit electrons; secondly, because the first collector 117 is applied with a positive bias voltage, the electrons emitted by the electron emitter 115 move toward the first collector 117 under the action of the electric field. During this process, some of the emitted electrons collide with the gas molecules in the through-cavity 131 to ionize and generate ions, and some of the emitted electrons are captured by the first collector 117 to form an electron flow I e Finally, since the second collector 150 is negatively biased, the ions generated by ionization under the action of the electric field can move toward the second collector 150 and are eventually captured by the second collector 150 to form an ion current I i Based on the ionization theory of gas (I i =SPI e ), ion current I i and the electron current I e The ratio is proportional to the gas pressure in the measured environment, so it can be used to characterize the change in gas pressure in the measured environment to achieve vacuum measurement.

[0051] As an example, during the ionization process of gas molecules in the environment to be measured, since the gas molecules in the through-hole 131 and the gas molecules outside the on-chip micro ionization vacuum sensor are gas molecules of the same component and have a concentration difference (the gas molecules in the through-hole 131 can be consumed by ionization), the gas molecules will continuously enter the through-hole 151. In addition, the process in which the external gas molecules enter the through-hole 131 and the internal and external pressures are the same can be regarded as an instantaneous process. That is, the gas pressure of the environment to be measured based on the gas ionization theory can be regarded as the gas pressure inside the on-chip micro ionization vacuum sensor, and can also be regarded as the gas pressure outside the on-chip micro ionization vacuum sensor.

[0052] Furthermore, the on-chip micro ionization vacuum sensor of the present application can also be connected to various pressure power sources in the following manner: a positive voltage is connected to the electrode pair 111 to drive the electron emitter 115 to emit electrons, and a negative bias is connected to the first collector 117 to collect ions generated by gas ionization. At this time, the second collector 150 can be connected to a positive bias to capture electrons, thereby determining the vacuum degree of the environment to be measured based on the ratio of the ion current formed by the first collector 117 collecting ions to the electron current formed by the second collector 150 collecting electrons.

[0053] In some embodiments of the present invention, the substrate 113 may be an insulating substrate, the insulating spacer layer 130 may be an insulating glass layer, ceramic layer, sapphire layer, silicon carbide layer or intrinsic silicon layer, and the second collector 150 may be a conductive silicon layer or a conductive metal layer.

[0054] More specifically, since the substrate 113 has the through-electrode pair 111, the substrate 113 can be an insulating substrate, that is, the substrate 113 is made of an insulating material, which can be the same as or different from the material of the insulating spacer layer 130. The substrate 113 can ensure insulation between the through-electrode pair 111 (that is, the first electrode 1111 and the second electrode 1112) and the first collector 117. For example, since the first electrode 1111 and the second electrode 1112 penetrate the substrate 113, the substrate 113 can be a TSV (Through Silicon Via) substrate or a TGV (Through Glass Via) substrate.

[0055] Because the first collector 117 and the second collector 150 are connected to an external power source, the insulating spacer 130 can be made of an insulating material to ensure insulation. Insulating materials include one or more of glass, ceramic, sapphire, silicon carbide, and intrinsic silicon. The second collector 150 is made of a conductive material, which can be a conductive silicon wafer or a metal. That is, the second collector 150 can be a conductive silicon layer or a conductive metal layer.

[0056] The above-mentioned specific materials are merely examples. This invention does not impose any specific restrictions on the materials used to make the insulating spacer layer 130; it can be any insulating material layer. This invention also does not impose any specific restrictions on the materials used to make the second collector 150; it can be any conductive material layer with ion capture functionality. Furthermore, this invention does not impose any specific restrictions on the materials used to make the substrate 113; it can be any insulating substrate. The TSV and TGV substrates mentioned above are merely examples and this invention is not limited to them.

[0057] Furthermore, the first electrode 1111 and the second electrode 1112 are used to apply a driving voltage and can be made of a conductive material, including one or more of metal, graphite, conductive silicon, and a metal-containing conductive paste. Furthermore, the materials used to make the first electrode 1111 and the second electrode 1112 are not necessarily the same. Furthermore, the first collector 117 can be made of a conductive material, including conductive silicon.

[0058] The metal, graphite, conductive silicon and metal-containing conductive paste mentioned above are only examples, and the present invention does not specifically limit the conductive materials for preparing the electrodes and the first collector 117 .

[0059] In some embodiments of the present invention, a through electrode pair 111 and a correspondingly connected electron emitter 115 constitute an electron emission source (the two ends of the electron emitter 115 are respectively connected to the first electrode 1111 and the second electrode 1112). Figure 1 The electron emission source may be a thermal electron emission source (i.e., the electron emitter 115 may be a thermal electron emitter), and the thermal electron emission source includes a first electrode 1111 penetrating the substrate 113, a second electrode 1112 penetrating the substrate 113, and a thermal electron emitter 115. The electron emitter 115 may be in a filamentous or sheet-like shape, but the present application is not limited thereto. Figure 4 As shown, the structure of the electron emission source can be as follows:

[0060] The thermal electron emitter is arched in a direction away from the insulating substrate 113 to form a sufficient heat dissipation gap between the thermal electron emitter and the substrate 113; or

[0061] A groove 119 is provided on the insulating substrate 113 located between the pair of electrodes 111 (and the groove 119 is provided on the side of the substrate 113 having the thermal electron emitter), and the thermal electron emitter is partially or completely suspended above the groove 119 to form a heat dissipation gap between the thermal electron emitter and the insulating substrate 113.

[0062] As an example, since the hot electron emitter generates Joule heat by applying a voltage to the through electrode pair 111, it is necessary to have a sufficient heat dissipation gap between the hot electron emitter and the substrate 113, and the trench 119 is provided to help the hot electron emitter dissipate heat, so the trench 119 can be provided one-to-one corresponding to the hot electron emitter.

[0063] For example, the hot electron emitter can be a conductive metal wire coated with a hot emission film prepared from a hot emission material, or a thin wire made of a hot emission material. The hot emission material includes one or more of yttrium oxide, barium oxide, aluminum oxide, lanthanum oxide, gadolinium oxide, scandium oxide, and calcium oxide, and the conductive metal wire is made of one or more of iridium, tungsten, molybdenum, and titanium nitride. The hot emission material and the conductive metal wire in the micro ionization vacuum sensor on a chip mentioned in the present application are only examples, and the present application is not limited thereto.

[0064] In some embodiments of the present application, the overall size of the micro ionization vacuum sensor on a chip can be 1*1*1mm-20*20*5mm, the height of the first collector 117 can be 0.3mm-3mm, the height of the insulating spacer layer 130 can be 0.5-4mm, and the height of the second collector 150 can be 0.1-0.3mm.

[0065] To facilitate the first collector 117 to collect the electrons emitted by the electron emitter 115 or the ions generated by the ionization of the gas, the height of the substrate 113 can be not less than the height of the first collector 117, for example, the height of the substrate 113 is 3mm, and the height of the first collector 117 is 2.8mm. The above-mentioned limitation that the height of the substrate 113 is not less than the height of the first collector 117 is only an example, and the present application is not limited thereto, as long as the first collector can collect the electrons generated by the electron emitter or the ions generated by the ionization of the gas.

[0066] In the present application, the shape of the through cavity 131 and the through hole 151 can be rectangular or cylindrical, and the present application is not limited to the shape thereof. In addition, the shape of the above-mentioned through electrode pair 111 can also be cylindrical or other shapes, and the present application is not limited to the shape of the through electrode pair.

[0067] In the present application, on-chip electron emitters can be used to mass-produce on-chip micro ionization vacuum sensors by combining micro-nano processing and anodic bonding processes. Compared with traditional ionization vacuum sensors, the on-chip micro ionization vacuum sensor has the advantages of small size, low power consumption, low cost and integration. Compared with other types of micro ionization vacuum sensors such as high-voltage discharge, the present application uses an electron emission source to emit electrons to collide and ionize gas molecules, thus having a lower operating voltage. At the same time, since the thermal electron emission source has a large emission current, high resistance to rough vacuum and high stability, the on-chip micro ionization vacuum sensor proposed in the present application can have a wider vacuum measurement range and higher stability.

[0068] Compared with the five-layer structure of the on-chip micro ionization vacuum sensor in the Chinese invention patent with the patent name of "an on-chip micro ionization vacuum sensor and a manufacturing method thereof" with the application number of 2019111328116, the measurement effect of the three-layer structure of the on-chip micro ionization vacuum sensor proposed in the present application is as shown in Figure 6 Compared with the five-layer structure of the sensor, the on-chip micro ionization vacuum sensor with the three-layer structure proposed in the present application has the advantages of small size, simple structure and easy processing. In the case of consistent gas pressure and electron current, the ion current collected by the on-chip micro ionization vacuum sensor of the present application is improved by an order of magnitude. For example, when the electron current is 0.01 mA, the ion current of the five-layer ionization vacuum sensor is 0.1 nA, and the ion current of the three-layer ionization vacuum sensor proposed in the present application is 2 nA. Based on the ionization theory of gas (I i = SPI e ), it can be known that the three-layer ionization vacuum sensor proposed in the present application has a higher ionization efficiency, thereby having a wider vacuum measurement range. In addition, since the number of gas molecules is small in a high vacuum environment, the collision current efficiency is low, which easily leads to a small ion current, and usually a complex circuit is needed to accurately detect the ion current. However, the three-layer ionization vacuum sensor in the present application can improve the ion current, thereby reducing the difficulty of detecting the ion current of the sensor device under high vacuum conditions.

[0069] Further, as shown in Figure 7 , in the pressure range of 1x10 -4 Pa~50Pa, the ratio (I i / I e ) of the ion current I i to the electron current I e and the pressure of the environment in which the on-chip micro ionization vacuum sensor of the present application is located has a good linear relationship. That is, the on-chip micro ionization vacuum sensor of the present application can realize a vacuum range of 1x10 -4Pa~50Pa. Compared with the ionized vacuum sensor prepared by most micro-nano processing technology, the on-chip micro ionized vacuum sensor has a wider vacuum measurement range, and the working pressure range can be 10 -5 Pa~10 3 Pa, covering more than 5 orders of magnitude of measurement span from high vacuum degree to medium vacuum degree.

[0070] As an example, the electron emission source in the on-chip micro ionized vacuum sensor can be other types of on-chip micro electron sources in addition to the thermionic electron emission source, such as on-chip micro tunneling field emission electron source, Spindt type on-chip electron source, silicon needle field emission electron source, MIM (metal-insulator-metal) multilayer tunneling electron source and surface tunneling electron source based on resistive switching material, etc. The type of electron emission source is not specifically limited by the utility model.

[0071] In some embodiments of the utility model, the electron emission and collection structure 110, the insulating spacer layer 130 and the second collection electrode 150 can be prepared by micro-nano processing technology, and then the semi-closed chamber (on-chip micro ionized vacuum sensor) is manufactured by anodic bonding. Anodic bonding can not only make the bonded device have good bonding airtightness and bonding strength, but also be simple and easy to operate. As shown in Figure 8 and Figure 9 The utility model provides a bonding method and process of a single on-chip micro ionized vacuum sensor, and the bonding sequence is as follows:

[0072] First, the insulating spacer layer 130 is arranged on the side of the electron emission and collection structure 110 with the electron emitter 115, and the electron emission and collection structure 110 and the insulating spacer layer 130 are bonded by an anodic bonding process to obtain a sensor first assembly; then, the second collection electrode 150 with the through hole 151 is arranged on the side of the sensor first assembly away from the electron emission and collection structure 110, and the sensor first assembly and the second collection electrode 150 are bonded by an anodic bonding process, and finally a single on-chip micro ionized vacuum sensor can be obtained.

[0073] In some embodiments of the utility model, a method for batch preparing on-chip micro ionized vacuum sensors by wafer processing is provided, as shown in Figure 10 and Figure 11 The specific steps are as follows:

[0074] Step S11: providing a first mother layer, a second mother layer and a third mother layer. The first mother layer has N electron emission and collection structures 110 arranged periodically, the second mother layer has N insulating spacer layers 130 arranged periodically, and the third mother layer has N second collection electrodes 150 arranged periodically.

[0075] The first mother layer, the second mother layer and the third mother layer can be prepared by using existing processing technology, which will not be described in detail here.

[0076] Step S12: bonding the first mother layer, the second mother layer and the third mother layer in sequence using an anodic bonding process.

[0077] For example, the first mother layer and the second mother layer can be bonded to the set installation position using an anodic bonding process to form a first bonding structure, and then the third mother layer and the first bonding structure can be bonded to the set installation position to obtain a second bonding structure.

[0078] Step S13: cutting the second bonding structure to obtain a plurality of on-chip micro ionization vacuum sensors.

[0079] The bonding process of the on-chip micro ionization vacuum sensor of the utility model described above has multiple bonding sequences. The embodiments of this application only provide one bonding sequence for illustration. The bonding sequence can be adjusted according to actual conditions, and this utility model does not specifically limit the bonding sequence. Furthermore, the above-mentioned method of bonding the various layers using anodic bonding is merely an example; other fixing methods, such as atomic bonding, can also be used.

[0080] The utility model provides an on-chip micro ionization vacuum sensor, which adopts an on-chip electron emission source with stable operation, low power consumption and resistance to rough vacuum, utilizes micro-nano processing technology to prepare a chamber with small size, light weight and simple structure, and combines semiconductor technology to realize on-chip wafer processing to batch prepare sensors, which not only realizes the miniaturization, on-chip and integration of vacuum electronic devices, but also can obtain a wider vacuum measurement range.

[0081] It should be understood that the present invention is not limited to the specific configurations and processes described above and illustrated in the figures. For the sake of brevity, detailed descriptions of known methods are omitted. In the above embodiments, several specific steps are described and illustrated as examples. However, the method process of the present invention is not limited to the specific steps described and illustrated. Those skilled in the art may make various changes, modifications, and additions, or change the order of the steps after understanding the spirit of the present invention.

[0082] In the present invention, features described and / or illustrated for one embodiment may be used in the same or similar manner in one or more other embodiments, and / or combined with or replace features of other embodiments.

[0083] The above merely describes preferred embodiments of the present application and is not intended to limit the present application. For those skilled in the art, the embodiments of the present application can be variously changed and modified. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. An on-chip micro ionization vacuum sensor, characterized in that: include: An electron emission and collection structure (110) comprises an insulating substrate (113), a pair of through-hole electrodes (111) formed on the insulating substrate (113), an electron emitter (115) located on the insulating substrate (113) and connected to the pair of through-hole electrodes (111), and a first collector (117) arranged closely around the outer periphery of the insulating substrate (113); the pair of through-hole electrodes (111) is used to be applied with a driving voltage to drive the electron emitter (115) to emit electrons; the first collector (117) is used to be applied with a positive voltage to collect electrons emitted by the electron emitter (115), or to be applied with a negative voltage to collect ions; An insulating spacer layer (130) is located on one side of the electron emission and collection structure (110) having the electron emitter (115), surrounding the electron emitter (115) to form a through cavity (131) between the electron emission and collection structure (110) and the second collector (150); a second collector (150) located on a side of the insulating spacer layer (130) away from the electron emission and collection structure (110), the second collector (150) being used to be applied with a negative voltage to capture ions reaching the second collector (150) via the through cavity (131), or to be applied with a positive voltage to collect electrons; the second collector (150) having a single or multiple through holes; The on-chip micro ionization vacuum sensor is used to determine the vacuum degree based on electrons and ions collected by the first collecting electrode (117) and the second collecting electrode (150), respectively.

2. The ionization vacuum sensor according to claim 1, characterized in that The insulating substrate (113) is a through-silicon via substrate or a through-glass via substrate.

3. The ionization vacuum sensor according to claim 1, characterized in that The insulating spacer layer (130) is a glass layer, a ceramic layer, a sapphire layer, a silicon carbide layer or an intrinsic silicon layer.

4. The ionization vacuum sensor according to claim 1, characterized in that The second collecting electrode (150) is a conductive silicon layer or a conductive metal layer.

5. The ionization vacuum sensor according to claim 1, characterized in that: The electron emission and collection structure (110) further includes an insulating layer (118) arranged closely around the first collector (117), so that the entire surface of the electron emitter (115) and the first collector (117) is exposed in the through cavity (131).

6. The ionization vacuum sensor according to claim 1, characterized in that The electron emitter (115) is a thermal electron emitter.

7. The ionization vacuum sensor according to claim 6, characterized in that: The electron emitter (115) is in the form of a wire or a sheet.

8. The ionization vacuum sensor according to claim 7, characterized in that: The electron emitter (115) is arched in a direction away from the insulating substrate (113) to form a heat dissipation gap between the electron emitter (115) and the insulating substrate (113); or A groove is provided on the insulating substrate (113) between the through-electrode pair (111), and the electron emitter (115) is at least partially suspended above the groove (119).

9. The ionization vacuum sensor according to claim 7, characterized in that: The thermal electron emitter is a conductive metal wire with a thermal emission film made of thermal emission material covered on the surface.

10. The ionization vacuum sensor according to claim 1, characterized in that The overall size of the ionization vacuum sensor is The height of the first collecting electrode (117) is 0.3 mm to 3 mm, the height of the insulating spacer layer (130) is 0.5 mm to 4 mm, and the height of the second collecting electrode (150) is 0.1 mm to 0.3 mm.

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