Preparation method of electronic device and electronic device
By forming a cavity structure on the silicon wafer and drying isopropanol, the deformation problem caused by liquid residue in the cavity structure is solved, and the yield and stability of electronic devices are improved.
Patent Information
- Application Number
- CN202411290785.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-09-14
- Publication Date
- 2024-12-17
AI Technical Summary
In the existing cavity structure processing technology, the residual liquid in the cavity can easily lead to structural deformation, resulting in failure of electronic devices, and low product yield.
By providing a multi-layer dielectric layer and photoresist on the silicon wafer, the vias are formed by a photolithography process, the dielectric layer is removed to form a cavity structure, and by drying at least twice, isopropanol is used with water in the cavity and The etching liquid undergoes chemical reactions to quickly remove residual moisture and avoid liquid residue.
It effectively avoids liquid residue in the cavity structure, improves the stability and yield of electronic devices, and reduces product failure efficiency.
Smart Images
Figure CN119143074A_ABST
Abstract
Description
Technical Field
[0001] The present application relates to the field of microelectronics technology, and in particular to a method for preparing an electronic device and an electronic device. Background Art
[0002] At present, the production process of MEMS (micro-electromechanical system) device chips involves a variety of cavity structures. For example, a cavity filter is a microwave filter that uses a resonant cavity structure. A cavity can be equivalent to an inductor in parallel with a capacitor, thereby forming a resonant level to achieve microwave filtering function; the core component of a capacitive microphone is the cavity composed of a diaphragm and a back plate. The diaphragm and the back plate cavity form a parallel plate capacitor. The diaphragm will be displaced under the action of sound wave pressure, causing the capacitance to change, thereby converting the sound signal into an electrical signal; there is also the bulk silicon cavity structure of a gas sensor, etc.
[0003] However, in the existing processing technology of the cavity structure, the residual liquid in the cavity can easily cause the cavity structure to deform, resulting in failure of the electronic device and low product yield. Summary of the invention
[0004] The embodiments of the present application provide a method for preparing an electronic device and an electronic device, which can improve the yield rate of electronic device products.
[0005] According to a first aspect of an embodiment of the present application, there is provided a method for preparing an electronic device, comprising:
[0006] A first dielectric layer and a second dielectric layer are sequentially arranged on one side of the silicon wafer, wherein the second dielectric layer covers the first dielectric layer;
[0007] Disposing a photoresist on a side of the second dielectric layer away from the silicon wafer, and patterning the photoresist using a photolithography process to form a plurality of first via holes on the photoresist;
[0008] Etching the second dielectric layer through the first via holes to form a plurality of second via holes in the second dielectric layer, wherein the first via holes are connected to the second via holes;
[0009] Removing the first dielectric layer through the second via hole to form a cavity structure in the second dielectric layer to obtain a transition substrate, wherein the second via hole is connected to the cavity structure, and an orthographic projection of the second via hole on the silicon wafer falls within an orthographic projection of the cavity structure on the silicon wafer;
[0010] The cavity structure is subjected to at least two drying processes, wherein at least one drying process is performed using isopropyl alcohol.
[0011] In some embodiments, the cavity structure is subjected to at least two drying processes, including:
[0012] Passing isopropyl alcohol into the cavity structure and the second via hole for the first time;
[0013] Isopropyl alcohol is introduced into the cavity structure and the second via hole for the second time.
[0014] In some embodiments, in the step of introducing isopropanol for the first time, the transition substrate is immersed in the isopropanol for a first time;
[0015] In the step of introducing isopropanol for the second time, the transition substrate is immersed in the isopropanol for a second time;
[0016] The first time is the same as the second time.
[0017] In some embodiments, the cavity structure is subjected to at least two drying processes, including:
[0018] Introducing isopropyl alcohol into the cavity structure and the second via hole;
[0019] Using hot nitrogen to purge the transition substrate surface and the cavity structure; and / or,
[0020] The transition substrate is baked in an oven.
[0021] In some embodiments, after the cavity structure is dried at least twice, the method further comprises:
[0022] Liquid carbon dioxide is introduced into the cavity structure and the second via hole to remove the isopropyl alcohol in the cavity structure and the second via hole.
[0023] In some embodiments, the time range of soaking the cavity structure with isopropanol for a single time is 5 to 10 minutes; and / or,
[0024] The temperature of the hot nitrogen is in the range of 40 to 60° C.; and / or,
[0025] The oven temperature range is 40 to 60°C.
[0026] In some embodiments, before the cavity structure is introduced with isopropanol, the method further comprises:
[0027] The surface of the transition substrate and the cavity structure are cleaned with deionized water at least once.
[0028] In some embodiments, the depth of the cavity structure is the same as the depth of the second via hole; and / or,
[0029] The sidewall of the cavity structure is parallel to the sidewall of the second via hole; or,
[0030] The diameter of the second via hole at one end close to the cavity structure is larger than the diameter of the second via hole at one end away from the cavity structure.
[0031] In some embodiments, the method for preparing an electronic device further comprises:
[0032] The diameter of the cavity structure at a side away from the silicon wafer is the same as the diameter of the cavity structure at a side close to the silicon wafer.
[0033] A second aspect of the embodiments of the present application provides an electronic device, which is prepared according to the method for preparing the electronic device according to the first aspect.
[0034] In the embodiment of the present application, a cavity structure is obtained by wet etching, and the cavity structure is dried at least twice, and isopropyl alcohol is used to chemically react with the water in the cavity and the etching solution diluted with water, respectively, to separate the residual water in the cavity structure and the etching solution diluted with water to the outside of the cavity structure. At the same time, isopropyl alcohol can quickly air-dry the residual water inside the cavity and the etching solution diluted with water. By subjecting the cavity structure to at least one isopropyl alcohol treatment, it is possible to prevent the residual liquid in the cavity of the cavity structure from being retained in the cavity structure, so that the cavity structure can stably support the membrane layer structure covering the upper layer of the cavity structure, thereby improving the yield of the product. BRIEF DESCRIPTION OF THE DRAWINGS
[0035] Figure 1 A schematic flowchart of a method for preparing an electronic device provided in an embodiment of the present application;
[0036] Figure 2 A schematic process flow chart of a method for preparing an electronic device provided in an embodiment of the present application;
[0037] Figure 3 A schematic partial diagram of an electronic device provided in an embodiment of the present application;
[0038] Figure 4 A schematic partial diagram of another electronic device provided in an embodiment of the present application;
[0039] Figure 5 A schematic structural diagram of an electronic device provided in an embodiment of the present application. DETAILED DESCRIPTION
[0040] In order to better understand the technical solutions provided by the embodiments of this specification, the technical solutions of the embodiments of this specification are described in detail below through the accompanying drawings and specific embodiments. It should be understood that the embodiments of this specification and the specific features in the embodiments are detailed descriptions of the technical solutions of the embodiments of this specification, rather than limitations on the technical solutions of this specification. In the absence of conflict, the embodiments of this specification and the technical features in the embodiments can be combined with each other.
[0041] In this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply that there is any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that the process, method, article or equipment including a series of elements includes not only those elements, but also includes other elements not explicitly listed, or also includes elements inherent to such process, method, article or equipment. In the absence of more restrictions, the elements limited by the statement "comprise one..." do not exclude the existence of other identical elements in the process, method, article or equipment including the elements. The term "more than two" includes two or more than two situations.
[0042] At present, various cavity structures are involved in the production process of MEMS device chips. For example, a cavity filter is a microwave filter that uses a resonant cavity structure. A cavity can be equivalent to an inductor in parallel with a capacitor, thus forming a resonant level to achieve microwave filtering function; the core component of a capacitive microphone is the cavity composed of a diaphragm and a back plate. The diaphragm and the back plate cavity form a parallel plate capacitor. The diaphragm will be displaced under the action of sound wave pressure, causing the capacitance to change, thereby converting the sound signal into an electrical signal; there is also the bulk silicon cavity structure of a gas sensor, etc.
[0043] However, in the existing processing technology of cavity structures, the residual liquid in the wall can easily cause the cavity structure to deform, resulting in failure of electronic devices and low product yield.
[0044] In view of this, the embodiments of the present application provide a method for preparing an electronic device and an electronic device, which can improve the yield rate of electronic device products.
[0045] According to a first aspect of an embodiment of the present application, a method for preparing an electronic device is provided. Figure 1 The following is a schematic flow chart of a method for preparing an electronic device provided in an embodiment of the present application. Figure 1 As shown, the method for preparing the electronic device:
[0046] S101: sequentially disposing a first dielectric layer and a second dielectric layer on one side of a silicon wafer, wherein the second dielectric layer covers the first dielectric layer.
[0047] Figure 2 A schematic process flow chart of a method for preparing an electronic device provided in an embodiment of the present application. Figure 2As shown, step S101: a first dielectric layer 200 and a second dielectric layer 300 are sequentially deposited on one side of a silicon wafer 100, wherein the first dielectric layer 200 is disposed between the silicon wafer 100 and the second dielectric layer 300. The first dielectric layer 200 may be silicon dioxide, and the second dielectric layer 300 may be polysilicon. The second dielectric layer 300 is disposed to cover the first dielectric layer 200.
[0048] S102: Disposing a photoresist on a side of the second dielectric layer away from the silicon wafer, and patterning the photoresist using a photolithography process to form a plurality of first via holes on the photoresist.
[0049] For example, Figure 2 As shown, step S102: spin-coating a photoresist 400 on a side of the second dielectric layer 300 away from the silicon wafer 100 , exposing and developing the photoresist 400 , completing the patterning process of the photoresist 400 , and forming a plurality of first via holes 410 in the photoresist 400 .
[0050] S103: etching the second dielectric layer through the first via holes to form a plurality of second via holes in the second dielectric layer, wherein the first via holes are connected to the second via holes.
[0051] For example, Figure 2 As shown, step S103 : dry-etching the second dielectric layer 300 through the first via hole 410 to form a second via hole 310 in the second dielectric layer 300 , and the first via hole 410 is connected to the second via hole 310 .
[0052] S104: removing the first dielectric layer through the second via hole to form a cavity structure in the second dielectric layer, thereby obtaining a transition substrate, wherein the second via hole is connected to the cavity structure, and an orthographic projection of the second via hole on the silicon wafer falls within an orthographic projection of the cavity structure on the silicon wafer.
[0053] For example, Figure 2 As shown, step S104: the first dielectric layer 200 is removed through the second via hole 310. The first dielectric layer 200 is used as a sacrificial layer. The first dielectric layer 200 and the photoresist 400 can be removed by using a wet etching liquid hydrofluoric acid to form a cavity structure 320 in the second dielectric layer 300, thereby obtaining a transition substrate 500. The second via hole 310 can be connected to the cavity structure 320. The orthographic projection of the second via hole 310 on the silicon wafer 100 falls within the orthographic projection of the cavity structure 320 on the silicon wafer 100.
[0054] S105: performing at least two drying processes on the cavity structure, wherein at least one drying process is performed using isopropyl alcohol.
[0055] Exemplary, the cavity structure 320 is dried at least twice, wherein at least one drying process is performed using isopropanol. The drying process may be to inject isopropanol into the cavity structure 320, and the isopropanol may react chemically with the residual water inside the cavity structure 320 and the hydrofluoric acid etching solution diluted with water, and separate the water and the hydrofluoric acid etching solution diluted with water from the inside of the cavity structure to the outside of the cavity structure 320. At the same time, the isopropanol may allow the water inside the cavity structure 320 and the hydrofluoric acid etching solution diluted with water to be air-dried quickly. By using isopropanol to dry the cavity structure, on the one hand, the water in the cavity structure and the hydrofluoric acid etching solution diluted with water may be separated to the outside of the cavity structure, and on the other hand, the isopropanol may accelerate the volatilization of the liquid inside the cavity structure, and the residual liquid in the cavity structure of the cavity structure may be prevented from being removed slowly, and the drying inside the cavity structure may be accelerated, thereby preventing the interface between the liquid and the air from generating a large surface tension, and the vertical component of its force may pull the two-layer structure of the cavity to be close, causing the structure to be deformed, and causing the electronic device to fail.
[0056] In the embodiment of the present application, a cavity structure is obtained by wet etching, and the cavity structure is dried at least twice, and isopropyl alcohol is used to chemically react with the water in the cavity and the etching solution diluted with water, respectively, to separate the residual water in the cavity structure and the etching solution diluted with water to the outside of the cavity structure. At the same time, isopropyl alcohol can quickly air-dry the residual water inside the cavity and the etching solution diluted with water. This avoids the slow removal of residual liquid in the cavity of the cavity structure, accelerates the drying of the cavity structure, and further avoids the generation of large surface tension at the interface between liquid and air, so that the cavity structure stably supports the membrane structure covering the upper layer of the cavity structure, thereby improving the yield of the product.
[0057] In some embodiments, in combination Figure 1 and Figure 2 , step S105 includes: performing a first isopropanol treatment on the cavity structure 320 and the second via 310 to separate the water in the cavity structure 320 and the hydrofluoric acid etching solution diluted by water to the outside of the cavity structure 320. Performing a second isopropanol treatment on the cavity structure 320 and the second via 310 to separate the water in the cavity structure 320 and the hydrofluoric acid etching solution diluted by water to the outside of the cavity structure 320. The first isopropanol treatment and the second isopropanol treatment use the same isopropanol concentration and the same flow rate of isopropanol. By performing the same isopropanol treatment twice on the inside of the cavity structure, it is possible to avoid the presence of residues in the cavity structure, and at the same time, it is possible to improve the consistency of the product drying process and accurately control the duration of the drying process of the cavity structure. While ensuring the product yield, the product processing efficiency is improved.
[0058] In some embodiments, in the step of passing isopropanol for the first time, the immersion time of the transition substrate 500 in isopropanol is the first time. In the step of passing isopropanol for the second time, the immersion time of the transition substrate 500 in isopropanol is the second time, and the first time is the same as the second time. The time of passing isopropanol twice can be set to be the same, and the concentration of passing isopropanol twice is also the same. By setting the immersion time of the transition substrate 500 of the drying process twice to be the same, the isopropanol concentration used is the same, and the purpose of gradient dehydration is achieved, so that the water inside the cavity structure 320 and the mixed liquid such as the etching solution diluted by water are completely replaced by isopropanol to the outside of the cavity structure 320, and the cavity structure 320 is completely occupied by isopropanol inside, and the volatile property of isopropanol is utilized again to obtain a cavity structure with good performance, thereby improving the yield rate of the product.
[0059] For example, Figures 1 to 2 As shown, the time of the first drying treatment isopropanol soaking can be 10s, the time of the second drying treatment isopropanol soaking can be 10s, and the concentration of the two isopropanols can be 99.9%. The time of the first drying treatment isopropanol soaking can be 20s, the time of the second drying treatment isopropanol soaking can be 10s, and the concentration of the two isopropanols can be 99.7%. The time of the first drying treatment isopropanol soaking can be 30s, the time of the second drying treatment isopropanol soaking can be 30s, and the concentration of the two isopropanols can be 99.5%. By setting the same soaking time of the transition substrate 500 for the two drying treatments and the same isopropanol concentration used, the purpose of gradient dehydration is achieved, so that the water inside the cavity structure 320 and the mixed liquid such as the etching solution diluted by water are completely replaced by isopropanol to the outside of the cavity structure 320, and the cavity structure 320 is completely occupied by isopropanol, and then the volatile property of isopropanol is used to obtain a cavity structure with good performance, thereby improving the yield of the product.
[0060] In some embodiments, Figures 1 to 2 As shown, step 105 includes: introducing isopropanol into the cavity structure 320 and the second via hole, performing a first drying process on the interior of the cavity structure 320 using isopropanol, and then using hot nitrogen to purge the surface of the transition substrate and the cavity structure 320 to complete a second drying process. The second drying process can also be performed by steaming and baking the transition substrate in an oven. The first drying process is a liquid drying process, and the second drying process is a gas drying process. Through the drying process method combining the liquid drying process and the gas drying process, the dry state inside the cavity structure 320 is further strengthened, the problem of residual corrosive liquid inside the cavity structure 320 is greatly reduced, the deformation of the cavity structure is avoided, and the yield of the product is improved.
[0061] For example, the time range of the isopropyl alcohol soaking the cavity structure 320 in the first drying process can be 10 to 30 seconds. The temperature range of the hot nitrogen in the second drying process can be 40 to 60°C, or the temperature range of the oven in the second drying process can be 40 to 60°C.
[0062] For example, when the time for soaking the cavity structure 320 with isopropyl alcohol once in the first drying process is 10 seconds, the temperature of the hot nitrogen in the second drying process may be 60° C. When the time for soaking the cavity structure 320 with isopropyl alcohol once in the first drying process is 20 seconds, the temperature of the hot nitrogen in the second drying process may be 50° C. When the time for soaking the cavity structure 320 with isopropyl alcohol once in the first drying process is 30 seconds, the temperature of the hot nitrogen in the second drying process may be 40° C.
[0063] For example, when the time for soaking the cavity structure 320 with isopropyl alcohol once in the first drying process is 10 seconds, the oven temperature range for the second drying process may be 60° C. When the time for soaking the cavity structure 320 with isopropyl alcohol once in the first drying process is 20 seconds, the oven temperature range for the second drying process may be 50° C. When the time for soaking the cavity structure 320 with isopropyl alcohol once in the first drying process is 30 seconds, the oven temperature range for the second drying process may be 40° C.
[0064] The embodiment of the present application further enhances the dry state inside the cavity structure through a drying treatment method that combines liquid drying treatment and gas drying treatment, greatly reduces the problem of residual corrosive liquid inside the cavity structure, avoids deformation of the cavity structure, and improves product reliability.
[0065] In some embodiments, Figures 1 to 2As shown, step S105 includes: introducing liquid carbon dioxide into the cavity structure 320 and the second via hole 310 to remove the isopropanol in the cavity structure 320 and the second via hole 310. The first drying treatment of the cavity structure 320 can be to introduce isopropanol into the cavity structure 320 to replace the water in the cavity structure 320 and the hydrofluoric acid etching solution diluted by water to the outside of the cavity structure 320. The second drying treatment of the cavity structure 320 can be to put the transition substrate into a supercritical drying machine, introduce liquid carbon dioxide into the cavity structure 320, use liquid carbon dioxide to replace the isopropanol in the cavity structure 320, then increase the temperature and pressure to make the carbon dioxide reach a supercritical state, and slowly release the carbon dioxide gas after maintaining it for a certain period of time to obtain a dry cavity structure. The first drying treatment and the second drying treatment of the cavity structure 320 are both liquid drying treatments. Through two liquid drying processes, in the supercritical state, there is no interface between the carbon dioxide gas and the isopropyl alcohol liquid, but a uniform fluid between gas and liquid is formed. This fluid is gradually discharged from the cavity, and there is no gas-liquid interface in the cavity structure 320, and there is no surface tension, which will not cause damage to the cavity structure 320, so that the yield of the device product is greatly improved.
[0066] In some embodiments, Figures 1 to 2 As shown, before the isopropanol is introduced into the cavity structure 320, the method further includes: performing at least one deionized water cleaning on the surface of the transition substrate and the cavity structure 320. The deionized water cleaning can be spray cleaning or immersion cleaning, and the surface of the transition substrate and the cavity structure 320 are rinsed with deionized water respectively. The deionized water cleaning can rinse away the hydrofluoric acid etching liquid on the surface of the transition substrate and inside the cavity structure 320. The deionized water cleaning of the transition substrate can be a single rinsing operation or multiple rinsing operations, which can avoid excessive etching of the residual hydrofluoric acid etching liquid, resulting in over-etching of the silicon wafer, thereby improving the reliability and yield of the electronic device.
[0067] In some embodiments, the depth of the cavity structure is the same as the depth of the second via hole, the sidewall of the cavity structure 320 is parallel to the sidewall of the second via hole, and the diameter of the cavity structure away from the silicon wafer is smaller than the diameter of the cavity structure close to the silicon wafer.
[0068] Figure 3 A schematic partial diagram of an electronic device provided in an embodiment of the present application, Figure 4 A schematic partial diagram of another electronic device provided in an embodiment of the present application. For example, Figures 1 to 4As shown, the depth of the cavity structure 320 is the first depth h1, and the depth of the second via hole 310 is the first depth h2, and the first depth h1 can be the same as the first depth h2. The angle between the side wall of the cavity structure 320 and the plane where the silicon wafer 100 is located is the first angle a, and the angle between the side wall of the second via hole 310 and the cavity structure 320 is the second angle. The first angle a is the same as the second angle b, and the side wall of the cavity structure 320 can be parallel to the side wall of the second via hole 310, and the angles of the first angle a and the second angle b can both be 90°. The caliber of the side of the cavity structure 320 away from the silicon wafer 100 is the first caliber, and the caliber of the side of the cavity structure close to the silicon wafer is the second caliber L2, and the first caliber L1 is smaller than the second caliber L2. The cavity structure 320 is surrounded by the second dielectric layer 300 and the silicon wafer, and the second via hole 310 can be used as a release hole of the cavity structure 320, and the sacrificial layer is arranged in the cavity structure 320. By setting the depth of the second via hole 310 to be the same as the depth of the cavity structure 320, the processing dimensions of the second dielectric layer 300 and the sacrificial layer can be accurately controlled to reduce the processing difficulty. By setting the first angle a and the second angle b to be the same, the etching angle of the cavity structure 320 can be accurately controlled to avoid over-etching and causing the cavity structure to collapse. By setting the first caliber L1 to be smaller than the second caliber L2, the sacrificial layer can be easily released from the release hole to the outside of the cavity structure 320.
[0069] The method for preparing an electronic device provided in the embodiment of the present application can accurately control the angle of the cavity structure, the depth of the cavity structure and the diameter of the cavity structure, which can not only reduce the processing difficulty of the process and improve the consistency of the electronic device, but also support the membrane layer structure arranged adjacent to the cavity structure to avoid deformation of the membrane layer structure, thereby improving the stability of the electronic device.
[0070] According to a second aspect of the embodiments of the present application, an electronic device is provided. Figure 5 The schematic structural diagram of an electronic device provided in an embodiment of the present application. The electronic device may be a cavity filter, a condenser microphone or a gas sensor. For example, Figure 5 As shown. The electronic device includes a silicon wafer 100 and a second dielectric layer 300, the second dielectric layer 300 is provided with a second via 310, a cavity structure 320 is provided between the second dielectric layer 300 and the silicon wafer 100, and a sacrificial layer is provided inside the cavity structure. The second via 310 is connected to the cavity structure 320, and the orthographic projection of the second via 310 on the silicon wafer 100 falls within the orthographic projection of the cavity structure 320 on the silicon wafer 100. A plurality of second vias 310 may be provided, and the orthographic projections of the plurality of second vias 310 on the silicon wafer 100 all fall within the orthographic projection of the cavity structure 320 on the silicon wafer 100, so that the sacrificial layer is released to the outside of the cavity structure 320 through the second via 310.
[0071] There is no residual liquid inside the cavity structure of the electronic device provided in the embodiment of the present application, which will not cause damage to the cavity structure, and the membrane layer structure arranged adjacent to the cavity structure will not be deformed, so that the yield of the device product is greatly improved.
[0072] It should be noted that in the above embodiments, the description of each embodiment has its own emphasis, and for parts that are not described in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.
[0073] Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working processes of the systems, devices and units described above can refer to the corresponding processes in the aforementioned method embodiments and will not be repeated here.
[0074] The above embodiments 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, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these 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.
[0075] Although the preferred embodiments of this specification have been described, those skilled in the art may make additional changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of this specification.
[0076] Obviously, those skilled in the art can make various changes and modifications to this specification without departing from the spirit and scope of this specification. Thus, if these modifications and variations of this specification fall within the scope of the claims of this specification and their equivalents, this specification is also intended to include these modifications and variations.
Claims
1. A method for preparing an electronic device, It is characterized in that include: A first dielectric layer and a second dielectric layer are sequentially arranged on one side of the silicon wafer, wherein the second dielectric layer covers the first dielectric layer; Disposing a photoresist on a side of the second dielectric layer away from the silicon wafer, and patterning the photoresist using a photolithography process to form a plurality of first via holes on the photoresist; Etching the second dielectric layer through the first via holes to form a plurality of second via holes in the second dielectric layer, wherein the first via holes are connected to the second via holes; Removing the first dielectric layer through the second via hole to form a cavity structure in the second dielectric layer to obtain a transition substrate, wherein the second via hole is connected to the cavity structure, and an orthographic projection of the second via hole on the silicon wafer falls within an orthographic projection of the cavity structure on the silicon wafer; The cavity structure is subjected to at least two drying processes, wherein at least one drying process is performed using isopropyl alcohol.
2. The method for preparing an electronic device according to claim 1, It is characterized in that The cavity structure is subjected to at least two drying processes, including: Passing isopropyl alcohol into the cavity structure and the second via hole for the first time; Isopropyl alcohol is introduced into the cavity structure and the second via hole for the second time.
3. The method for preparing an electronic device according to claim 2, It is characterized in that In the step of introducing isopropanol for the first time, the transition substrate is immersed in the isopropanol for a first time; In the step of introducing isopropanol for the second time, the transition substrate is immersed in the isopropanol for a second time; The first time is the same as the second time.
4. The method for preparing an electronic device according to claim 1, It is characterized in that The cavity structure is subjected to at least two drying processes, including: Introducing isopropyl alcohol into the cavity structure and the second via hole; Using hot nitrogen to purge the transition substrate surface and the cavity structure; and / or, The transition substrate is baked in an oven.
5. The method for preparing an electronic device according to claim 4, It is characterized in that After the cavity structure is dried at least twice, the method further comprises: Liquid carbon dioxide is introduced into the cavity structure and the second via hole to remove the isopropyl alcohol in the cavity structure and the second via hole.
6. The method for preparing an electronic device according to claim 4, It is characterized in that The time range of soaking the cavity structure with isopropyl alcohol is 5 to 10 minutes; and / or, The temperature of the hot nitrogen is in the range of 40 to 60° C.; and / or, The oven temperature range is 40 to 60°C.
7. The method for preparing an electronic device according to claim 1, It is characterized in that Before the isopropanol is introduced into the cavity structure, the method further comprises: The surface of the transition substrate and the cavity structure are cleaned with deionized water at least once.
8. The method for preparing an electronic device according to claim 7, It is characterized in that The depth of the cavity structure is the same as the depth of the second via hole; and / or, The sidewall of the cavity structure is parallel to the sidewall of the second via hole; or, The diameter of the second via hole at one end close to the cavity structure is larger than the diameter of the second via hole at one end away from the cavity structure.
9. The method for preparing an electronic device according to claim 8, It is characterized in that Also includes: The diameter of the cavity structure at a side away from the silicon wafer is the same as the diameter of the cavity structure at a side close to the silicon wafer.
10. An electronic device, It is characterized in that The electronic device is prepared according to the method for preparing the electronic device according to any one of claims 1 to 9.