Vacuum-degree-adjustable device packaging method, MEMS structure and sensor

Abstract

The invention is suitable for the technical field of device packaging, and provides a vacuum-degree-adjustable device packaging method, an MEMS structure and a sensor, and the method comprises the steps: placing a getter in a cavity of a target device; vacuumizing the cavity of the target device; filling the cavity of the target device with target gas to complete packaging of the target device; wherein the target gas at least comprises gas capable of being absorbed by the getter, and the type and / or the mass of the getter are / is determined according to the vacuum degree requirement of the target device, or the volume and the pressure of the target gas are / is determined according to the vacuum degree requirement of the target device. The vacuum degree of the device can be accurately controlled, and adjustment of the vacuum degree is achieved.

Description

Technical Field

[0001] The present application belongs to the field of device packaging technology, and in particular relates to a device packaging method with adjustable vacuum degree, a MEMS structure and a sensor. Background Art

[0002] The MEMS (pressure sensor or inertial sensor) structure has a cavity structure. The cavity in the MEMS sensor requires a certain degree of vacuum to ensure the stable operation of the device. However, in MEMS sensors, the higher the vacuum degree, the better. Some products require a specific vacuum degree, and each device has different requirements for vacuum degree.

[0003] In the existing technology, the air in the cavity is directly pumped out to form an environment with a corresponding vacuum degree. However, the methods of the existing technology are difficult to accurately control the vacuum degree. In addition, the same type of MEMS sensor sometimes requires different vacuum degrees, and the method of directly pumping out the air in the cavity to achieve different vacuum degrees is also relatively cumbersome. Summary of the invention

[0004] In order to overcome the technical problem in the related art that the vacuum degree of a device is difficult to accurately control, the embodiments of the present application provide a device packaging method, a MEMS structure and a sensor with adjustable vacuum degree.

[0005] This application is implemented through the following technical solutions: In a first aspect, an embodiment of the present application provides a device packaging method with adjustable vacuum degree, comprising: A getter is placed into the cavity of the target device.

[0006] Evacuate the cavity of the target device.

[0007] Fill the target gas into the cavity of the target device to complete the packaging of the target device; wherein the target gas at least includes a gas that can be absorbed by a getter, and the type and / or quality of the getter is determined according to the vacuum requirement of the target device, or the volume and pressure of the target gas are determined according to the vacuum requirement of the target device.

[0008] In combination with the first aspect, in some possible implementations, the getter is wrapped by a protective film.

[0009] In combination with the first aspect, in some possible implementations, the getter is wrapped by a protective film, and each protective film has a different melting point; a plurality of getter placement areas are provided in the cavity of the target device, and the type of getter placed in each getter placement area is the same.

[0010] In combination with the first aspect, in some possible implementations, the getter is wrapped by a protective film, and each protective film has a different melting point; a plurality of getter placement areas are provided in the cavity of the target device, and the type of getter placed in each getter placement area is different.

[0011] In combination with the first aspect, in some possible implementations, the sizes of the multiple getter placement areas are the same.

[0012] In combination with the first aspect, in some possible implementations, the sizes of the multiple getter placement areas are different.

[0013] In combination with the first aspect, in some possible implementations, the getter is at least one of titanium, zirconium, hafnium and thorium.

[0014] In combination with the first aspect, in some possible implementations, the getter has a shape including powder, disc, strip, tube, ring or cup.

[0015] In a second aspect, an embodiment of the present application provides a MEMS structure, which is prepared by a device packaging method with adjustable vacuum degree as shown in any one of the first aspects.

[0016] In a third aspect, an embodiment of the present application provides a sensor, the sensor comprising at least one MEMS structure as shown in the second aspect.

[0017] It can be understood that the beneficial effects of the second and third aspects mentioned above can be found in the relevant description of the first aspect mentioned above, and will not be repeated here.

[0018] Compared with the prior art, the embodiments of the present invention have the following beneficial effects: The present application first places a getter in the cavity of the target device, then evacuates the cavity of the target device, and then fills the cavity of the target device with a target gas that can be absorbed by the getter. In this way, the total amount of target gas filled can be controlled by controlling the type and / or mass of the placed getter, or by controlling the volume and pressure of the target gas filled, thereby controlling the vacuum degree of the target device. The principle is to obtain and maintain a high vacuum through vacuuming and gettering, while the gas that is not absorbed by the getter adjusts the vacuum degree. By adjusting the gas ratio and matching the getter, the device can accurately reach and maintain the required vacuum degree, and can achieve precise control of the vacuum degree to meet packaging requirements of different vacuum degrees.

[0019] It is to be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the present specification. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the technical solutions in the embodiments of the present application, 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 It is a schematic flow chart of a device packaging method with adjustable vacuum degree provided in one embodiment of the present application; Figure 2 It is a form of a protective film wrapped getter provided in an embodiment of the present application; Figure 3 It is another form of the protective film wrapping the getter provided in one embodiment of the present application; Figure 4 This is a schematic diagram of the size of the getter placement area provided in one embodiment of the present application; Figure 5 This is another schematic diagram of the size of the getter placement area provided in one embodiment of the present application. DETAILED DESCRIPTION

[0022] In the following description, specific details such as specific system structures, technologies, etc. are provided for the purpose of illustration rather than limitation, so as to provide a thorough understanding of the embodiments of the present application. However, it should be clear to those skilled in the art that the present application may also be implemented in other embodiments without these specific details. In other cases, detailed descriptions of well-known systems, devices, circuits, and methods are omitted to prevent unnecessary details from obstructing the description of the present application.

[0023] It should be understood that when used in the present specification and the appended claims, the term "comprising" indicates the presence of described features, wholes, steps, operations, elements and / or components, but does not exclude the presence or addition of one or more other features, wholes, steps, operations, elements, components and / or combinations thereof.

[0024] It should also be understood that the term “and / or” used in the specification and appended claims refers to any and all possible combinations of one or more of the associated listed items, and includes these combinations.

[0025] As used in the specification and appended claims of this application, the term "if" can be interpreted as "when" or "uponce" or "in response to determining" or "in response to detecting", depending on the context. Similarly, the phrase "if it is determined" or "if [described condition or event] is detected" can be interpreted as meaning "uponce it is determined" or "in response to determining" or "uponce [described condition or event] is detected" or "in response to detecting [described condition or event]", depending on the context.

[0026] In addition, in the description of the present application specification and the appended claims, the terms "first", "second", "third", etc. are only used to distinguish the descriptions and cannot be understood as indicating or implying relative importance.

[0027] References to "one embodiment" or "some embodiments" etc. described in the specification of this application mean that one or more embodiments of the present application include specific features, structures or characteristics described in conjunction with the embodiment. Therefore, the statements "in one embodiment", "in some embodiments", "in some other embodiments", "in some other embodiments", etc. that appear in different places in this specification do not necessarily refer to the same embodiment, but mean "one or more but not all embodiments", unless otherwise specifically emphasized in other ways. The terms "including", "comprising", "having" and their variations all mean "including but not limited to", unless otherwise specifically emphasized in other ways.

[0028] Embodiment 1: The present application provides a device packaging method with adjustable vacuum degree. Figure 1 is a schematic diagram of a device packaging method with adjustable vacuum degree provided in an embodiment of the present application, with reference to Figure 1 The packaging method of the device with adjustable vacuum degree is described in detail as follows: Step 101 , placing a getter into a cavity of a target device.

[0029] Step 102: evacuate the cavity of the target device.

[0030] Step 103, filling the target gas into the cavity of the target device to complete the packaging of the target device; wherein the target gas at least includes a gas that can be absorbed by the getter, and the type and / or quality of the getter is determined according to the vacuum requirement of the target device, or the volume and pressure of the target gas are determined according to the vacuum requirement of the target device.

[0031] Specifically, the target gas to be filled can be a mixed gas of a preset proportion, a preset volume and a preset pressure. The gas that can be absorbed by the getter is recorded as the first gas. The volume of the gas that can be absorbed by the getter can be the product of the proportion of the first gas in the mixed gas and the preset volume; wherein, the proportion of the first gas is obtained by the preset proportion.

[0032] In some specific embodiments, in addition to the situation in Embodiment 1 described above, there are multiple situations, as follows: Embodiment 2: The scheme in this embodiment is based on embodiment 1.

[0033] On this basis, if Figure 2 As shown, the getter 201 in the cavity of the target device is also wrapped by a protective film 202 .

[0034] For example, Figure 2 The embodiment shown is only a form in which the getter 201 is still wrapped by the protective film 202. At this time, the getter 201 is in contact with the inner wall of the cavity of the target device ( Figure 2 The getter 201 is also wrapped by the protective film 202 and can also be as follows Figure 3 The form shown: the getter 201 is also wrapped by a protective film 202, and the protective film is adhered to the inner wall of the cavity of the target device ( Figure 3 on the dotted line in the figure).

[0035] Specifically, the material of the protective film is a hot-melt material, which will melt when the temperature reaches a certain range, releasing the getter in the protective film. This can reduce the time the getter is exposed to the air, improve the getter performance, and ensure the accuracy of vacuum control.

[0036] Embodiment 3: The scheme in this embodiment is based on embodiment 1.

[0037] On this basis, the getter is wrapped by a protective film, and each protective film has a different melting point; a plurality of getter placement areas are provided in the cavity of the target device, and the type of getter placed in each getter placement area is the same.

[0038] Embodiment 4: The scheme in this embodiment is based on embodiment 1.

[0039] On this basis, the getter is wrapped by a protective film, and each protective film has a different melting point; a plurality of getter placement areas are provided in the cavity of the target device, and the type of getter placed in each getter placement area is different.

[0040] Specifically, the different melting points of each protective film means that the same type of MEMS structure can be controlled in real time to have different vacuum levels according to different annealing temperatures, which is simpler and easier to control than the traditional method of directly extracting the air from the cavity. In short, the annealing temperature can be directly controlled to directly control the A-type MEMS structure on the production line to have a variety of different vacuum levels, meet the different packaging requirements of the same type of MEMS sensors, and release the best performance.

[0041] Embodiment 5: The scheme in this embodiment is based on embodiment 3 or 4.

[0042] On this basis, if Figure 3 As shown, a plurality of getter placement areas 301 are provided in the cavity of the target device, and the sizes of the plurality of getter placement areas 301 are the same.

[0043] Embodiment 6: The scheme in this embodiment is based on embodiment 3 or 4.

[0044] On this basis, if Figure 4 As shown, a plurality of getter placement areas 301 are provided in the cavity of the target device, and the sizes of the plurality of getter placement areas 301 are different.

[0045] Specifically, the size of the getter placement area affects the amount of getter placed, and most directly affects the volume of the target gas that the getter can absorb. Different sizes of the getter placement area can improve the work efficiency of the getter according to different gradients, reduce the time to reach the target vacuum, and improve the production efficiency of the MEMS structure.

[0046] Specifically, the getter can be coated on the inner wall of the cavity of the target device by a protective film. The getter can be in the form of powder, disc, strip, tube, ring and cup; the getter is at least one of titanium, zirconium, hafnium and thorium.

[0047] The above-mentioned device packaging method with adjustable vacuum degree first places a getter in the cavity of the target device, then evacuates the cavity of the target device, and then fills the cavity of the target device with a target gas that can be absorbed by the getter. In this way, the vacuum degree of the target device can be controlled by controlling the type and / or quality of the placed getter, or by controlling the volume and pressure of the target gas filled in, thereby controlling the total amount of the target gas filled. The principle is to obtain and maintain a high vacuum by evacuating and using a getter, and the gas that is not absorbed by the getter adjusts the vacuum degree. By adjusting the gas ratio and the matching of the getter, the device can accurately reach and maintain the required vacuum degree, and can achieve precise control of the vacuum degree to meet packaging requirements of different vacuum degrees.

[0048] An embodiment of the present application also provides a MEMS structure, which is prepared by any of the above-mentioned device packaging methods with adjustable vacuum degree.

[0049] An embodiment of the present application further provides a sensor, which includes at least one MEMS structure shown in any one of the above items.

[0050] It should be understood that the size of the serial numbers of the steps in the above embodiments does not mean the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present application.

[0051] In the above embodiments, the description of each embodiment has its own emphasis. For parts that are not described or recorded in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0052] Those of ordinary skill in the art will appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of this application.

[0053] In the embodiments provided in the present application, it should be understood that the disclosed devices / network equipment and methods can be implemented in other ways. For example, the device / network equipment embodiments described above are merely schematic. For example, the division of the modules or units is only a logical function division. There may be other division methods in actual implementation, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.

[0054] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0055] The embodiments described above are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, a person skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. Such modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present application, and should all be included in the protection scope of the present application.

Claims

1. A device packaging method with adjustable vacuum degree, characterized in that: include: placing a getter into a cavity of a target device; evacuating a cavity of the target device; Filling the cavity of the target device with a target gas to complete the packaging of the target device; wherein the target gas includes at least a gas that can be absorbed by the getter, and the type and / or quality of the getter is determined according to the vacuum requirement of the target device, or the volume and pressure of the target gas is determined according to the vacuum requirement of the target device.

2. The device packaging method with adjustable vacuum degree according to claim 1, characterized in that: The getter is wrapped by a protective film.

3. The device packaging method with adjustable vacuum degree according to claim 1, characterized in that: The getter is wrapped by a protective film, and each protective film has a different melting point; a plurality of getter placement areas are arranged in the cavity of the target device, and the getter placed in each getter placement area is of the same type.

4. The device packaging method with adjustable vacuum degree according to claim 1, characterized in that: The getter is wrapped by a protective film, and each protective film has a different melting point; a plurality of getter placement areas are arranged in the cavity of the target device, and the getter placed in each getter placement area is of a different type.

5. The device packaging method with adjustable vacuum degree according to claim 3 or 4, characterized in that: The plurality of getter placement areas have the same size.

6. The device packaging method with adjustable vacuum degree according to claim 3 or 4, characterized in that: The multiple getter placement areas have different sizes.

7. The device packaging method with adjustable vacuum degree according to claim 1, characterized in that: The getter is at least one of titanium, zirconium, hafnium and thorium.

8. The device packaging method with adjustable vacuum degree according to claim 1, characterized in that: The getter may be in the form of powder, disc, strip, tube, ring or cup.

9. A MEMS structure, characterized in that: The MEMS structure is prepared by the device packaging method with adjustable vacuum degree as described in claims 1 to 8.

10. A sensor, characterized in that: Comprising at least one MEMS structure as claimed in claim 9.

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