A method for preparing a semiconductor mold and a method for preparing a cell culture plate

Abstract

A method for preparing a semiconductor mold and a method for preparing a cell culture plate, the method comprising: etching a semiconductor wafer of a certain thickness with a patterned mask layer as a mask, forming a first opening in the semiconductor wafer at the bottom of the mask opening; forming a protective film on the sidewall surface and the bottom surface of the first opening; performing feature etching on the protective film and the semiconductor wafer at the bottom of the first opening, wherein the etching rate of the central area of ​​the protective film on the bottom surface of the first opening is greater than the etching rate of the peripheral area of ​​the protective film on the bottom surface of the first opening, and the etching depth of the central area of ​​the semiconductor wafer at the bottom of the first opening is greater than the etching depth of the peripheral area of ​​the semiconductor wafer at the bottom of the first opening, so as to form a V-shaped opening connected to the sidewall of the first opening in the semiconductor wafer at the bottom of the first opening; and then removing the patterned mask layer. The processing difficulty is reduced, the processing efficiency is improved, and the processing cost is reduced.

Description

Technical Field

[0001] The invention relates to the technical field of mold manufacturing, and in particular to a method for preparing a semiconductor mold and a method for preparing a cell culture plate. Background Art

[0002] In cell biology, the culture of cell groups or embryoid bodies is a common basic experiment. The cell culture plates used for culture are large in quantity and have high requirements, which play an important role in the success or failure of cell culture experiments. Due to the production technology and cost of cell culture plates, this type of consumables is currently monopolized by several foreign biological product companies. Therefore, on the basis of controlling the cost of cell culture plates, making cell culture plates that meet the requirements can serve domestic biological sciences and research well, and can also get rid of dependence on similar foreign products.

[0003] Cell culture plates can be divided into flat bottom and round bottom according to the shape of the bottom. The choice of flat bottom and round bottom cell culture plates depends on the type of cells to be cultured. Suspended cells generally have the same charge, will repel each other and will not aggregate, so V-shaped culture plates are generally used for the culture of suspended cells. Thanks to the special geometric structure of the V-shape, cells can be aggregated in a very small range under the action of gravity.

[0004] The V-shaped holes in the V-shaped cell culture plate are usually between tens of microns and hundreds of microns, which are relatively small on a macro scale. Usually, multiple V-shaped holes are arranged in an array. The current commercial production method is: use fine cutting and grinding methods or 3D printing technology to process hard materials to form an inverted V-shaped cone array; use the inverted V-shaped cone array of the hard material as a mold, and use the mold to mold other soft organic materials suitable for cell culture through molding to form a V-hole array, that is, a cell culture plate with micropores. As mentioned above, mold making is a key link in the entire cell culture plate production, and it is also the most difficult link.

[0005] At present, the materials used for processing molds using fine cutting and grinding methods are generally glass or ceramics. The inverted V-shaped microstructure of the mold is small (usually between tens of microns and hundreds of microns), and the processing is difficult, inefficient, and costly using fine cutting and grinding methods and 3D printing technology. Summary of the invention

[0006] The technical problem to be solved by the present invention is to overcome the problems of great processing difficulty, low processing efficiency and high processing cost in the preparation method of semiconductor molds and cell culture plates in the prior art.

[0007] In order to solve the above technical problems, the present invention provides a method for preparing a semiconductor mold, comprising: providing a semiconductor wafer; forming a patterned mask layer on one side surface of the semiconductor wafer, wherein the patterned mask layer has a plurality of mask openings arranged in an array; etching a semiconductor wafer of a portion of thickness using the patterned mask layer as a mask to form a first opening in the semiconductor wafer at the bottom of the mask opening; forming a protective film on the side wall surface and the bottom surface of the first opening; performing feature etching on the protective film and the semiconductor wafer at the bottom of the first opening, wherein in the feature etching, the etching rate of the central area of ​​the protective film on the bottom surface of the first opening is greater than the etching rate of the peripheral area of ​​the protective film on the bottom surface of the first opening, and the etching depth of the central area of ​​the semiconductor wafer at the bottom of the first opening is greater than the etching depth of the peripheral area of ​​the semiconductor wafer at the bottom of the first opening, so as to form a V-shaped opening connected to the side wall of the first opening in the semiconductor wafer at the bottom of the first opening; after the V-shaped opening is formed, removing the patterned mask layer and the remaining protective film.

[0008] Optionally, the material of the semiconductor wafer includes single crystal silicon.

[0009] Optionally, the process of etching a portion of the thickness of the semiconductor wafer using the patterned mask layer as a mask to form a first opening in the semiconductor wafer at the bottom of the mask opening comprises a Bosch process.

[0010] Optionally, the depth of the first opening is 10 μm to 100 μm; the diameter of the first opening is 50 μm to 500 μm.

[0011] Optionally, the process for forming the protective film includes a plasma vapor chemical deposition process, and the parameters include: the chamber pressure is 0.3Pa~10Pa, the gases used include C4F8 and O2, the flow rate of C4F8 is 5sccm~50sccm, the flow rate of O2 is 5sccm~100sccm, the temperature is 0℃~70℃, the source RF power is 30W~10000W, and the time is 1min~1h.

[0012] Optionally, the protective film has a thickness of 0.1 μm to 5 μm.

[0013] Optionally, the feature etching is a plasma etching process, and the parameters include: chamber pressure of 0.3Pa~10Pa, gases used include SF6, O2 and Ar, SF6 flow rate of 5sccm~50sccm, O2 flow rate of 5sccm~100sccm, Ar flow rate of 0sccm~100sccm, temperature of 0℃~70℃, source RF power of 30W~10000W, bias RF power of 10W~2000W, and time of 10s~30min.

[0014] The present invention also provides a method for preparing a cell culture plate, comprising: providing a semiconductor mold, which is formed by the method for preparing a semiconductor mold of the present invention; forming a transition mold on the semiconductor mold by a reverse molding process, wherein the transition mold includes a base layer and a protrusion located on a partial surface of the base layer, wherein the protrusion includes a first protrusion area corresponding to the first opening and a second protrusion area corresponding to the V-shaped opening; demolding and separating the transition mold from the semiconductor mold; after demolding and separating the transition mold from the semiconductor mold, forming a cell culture plate on the transition mold by a reverse molding process, wherein the cell culture plate has a target opening, wherein the target opening includes a second opening corresponding to the first protrusion area and a third opening corresponding to the second protrusion area; demolding and separating the transition mold from the cell culture plate.

[0015] Optionally, it also includes: before forming a transition mold on the semiconductor mold by adopting a reverse molding process, forming a first release layer on the side wall of the first opening, the inner wall surface of the V-shaped opening, and the surface of the semiconductor mold between adjacent first openings; in the step of forming a transition mold on the semiconductor mold by adopting a reverse molding process, the transition mold covers the first release layer; after demolding and separating the transition mold from the semiconductor mold, and before forming a cell culture plate on the transition mold by adopting a reverse molding process, a second release layer is formed on the surface of the protrusion and the base surface of the side of the protrusion; in the step of forming a cell culture plate on the transition mold by adopting a reverse molding process, the cell culture plate covers the second release layer.

[0016] Optionally, the process for forming the first release layer and the second release layer is a plasma vapor chemical deposition process, and the parameters include: the chamber pressure is 0.3Pa~10Pa, the gases used include C4F8 and O2, the flow rate of C4F8 is 5sccm~50sccm, the flow rate of O2 is 5sccm~100sccm, the temperature is 0℃~70℃, the source RF power is 30W~10000W, and the time is 1s~5min.

[0017] Optionally, the method of forming a transition mold on the semiconductor mold using a reverse molding process includes: providing a first molding solution; coating the first molding solution on the side walls of the first opening and the inner wall surfaces of the V-shaped opening and the surface of the semiconductor mold between adjacent first openings; and curing the first molding solution to form a transition mold.

[0018] Optionally, the first molding solution includes silicone rubber liquid and a curing agent.

[0019] Optionally, the mass ratio of the silicone rubber liquid to the curing agent is 6:1 to 12:1.

[0020] Optionally, parameters for curing the first molding solution include: a curing temperature of 60 degrees Celsius to 100 degrees Celsius, and a curing time of 30 minutes to 90 minutes.

[0021] Optionally, the method of forming a cell culture plate by using a reverse molding process on the transition mold includes: providing a second molding solution; coating the second molding solution on the surface of the protrusion and the base layer on the side of the protrusion; and curing the second molding solution to form a cell culture plate.

[0022] Optionally, the second molding solution includes silicone rubber liquid and a curing agent.

[0023] Optionally, the mass ratio of the silicone rubber liquid to the curing agent is 6:1 to 12:1.

[0024] Optionally, parameters for curing the second molding solution include: a curing temperature of 60 degrees Celsius to 100 degrees Celsius, and a curing time of 30 minutes to 90 minutes.

[0025] The technical solution of the present invention has the following technical effects:

[0026] The method for preparing a semiconductor mold provided by the technical solution of the present invention forms a first opening and a V-shaped opening in a semiconductor wafer, and the semiconductor wafer having the first opening and the V-shaped opening constitutes a semiconductor mold. The process based on etching semiconductor wafers is a highly integrated technology that can form microstructures as small as a few nanometers. There is no need to use fine cutting and grinding methods and 3D printing technology, but etching technology in the semiconductor industry is used. The method for preparing a semiconductor mold has low processing difficulty, high processing efficiency, and low processing cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0028] Figure 1 A flowchart of a method for preparing a semiconductor mold provided by an embodiment of the present invention;

[0029] Figures 2 to 10 A structural diagram of a semiconductor mold preparation process provided by an embodiment of the present invention;

[0030] Fig.11 This is a local electron microscope image of a semiconductor die;

[0031] Figure 12 to Figure 13This is a structural diagram of a preparation process of a cell culture plate provided in another embodiment of the present invention. DETAILED DESCRIPTION

[0032] The technical solution of the present invention will be described clearly and completely below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0033] In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0034] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, it can also be the internal connection of two components, it can be a wireless connection, or it can be a wired connection. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0035] In addition, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0036] This embodiment provides a method for preparing a semiconductor mold, referring to Figure 1 ,include:

[0037] Step S1: providing a semiconductor wafer;

[0038] Step S2: forming a patterned mask layer on one side surface of the semiconductor wafer, wherein the patterned mask layer has a plurality of mask openings arranged in an array;

[0039] Step S3: etching a portion of the thickness of the semiconductor wafer using the patterned mask layer as a mask to form a first opening in the semiconductor wafer at the bottom of the mask opening;

[0040] Step S4: forming a protective film on the side wall surface and the bottom surface of the first opening;

[0041] Step S5: performing feature etching on the protective film and the semiconductor wafer at the bottom of the first opening, wherein in the feature etching, the etching rate of the central area of ​​the protective film on the bottom surface of the first opening is greater than the etching rate of the peripheral area of ​​the protective film on the bottom surface of the first opening, and the etching depth of the central area of ​​the semiconductor wafer at the bottom of the first opening is greater than the etching depth of the peripheral area of ​​the semiconductor wafer at the bottom of the first opening, so as to form a V-shaped opening connected to the side wall of the first opening in the semiconductor wafer at the bottom of the first opening;

[0042] Step S6: After forming the V-shaped opening, removing the patterned mask layer and the remaining protective film.

[0043] In this embodiment, a first opening and a V-shaped opening are formed in a semiconductor wafer, and the semiconductor wafer having the first opening and the V-shaped opening constitutes a semiconductor mold. The process based on etching a semiconductor wafer is a highly integrated technology that can form a microstructure as small as a few nanometers. There is no need to use fine cutting and grinding methods and 3D printing technology, but etching technology in the semiconductor industry is used. The preparation method of the semiconductor mold has low processing difficulty, high processing efficiency, and low processing cost.

[0044] Figures 2 to 10 A structural diagram of a semiconductor mold preparation process provided by an embodiment of the present invention.

[0045] refer to Figure 2 and Figure 3 , Figure 3 The top view of the patterned mask layer is provided. A semiconductor wafer 100 is provided. A patterned mask layer 110 is formed on one side surface of the semiconductor wafer 100 . The patterned mask layer 110 has a plurality of mask openings 111 arranged in an array.

[0046] In this embodiment, the semiconductor wafer 100 is made of single crystal silicon. In other embodiments, the semiconductor wafer 100 is made of other semiconductor materials.

[0047] In one embodiment, the material of the patterned mask layer 110 is photoresist.

[0048] In one embodiment, the cross-sectional shape of the mask opening 111 is circular. In other embodiments, the cross-sectional shape of the mask opening 111 can be designed as required.

[0049] refer to Figure 4 , Figure 4 For Figure 2Based on the schematic diagram, a portion of the thickness of the semiconductor wafer 100 is etched using the patterned mask layer 110 as a mask to form a first opening 120 in the semiconductor wafer 100 at the bottom of the mask opening 111.

[0050] In this embodiment, the cross-sectional shape of the first opening 120 is circular. In other embodiments, the cross-sectional shape of the first opening 120 can be designed as required.

[0051] In one embodiment, the depth of the first opening is 10 μm to 100 μm, for example, 10 μm, 20 μm, 50 μm, 80 μm or 100 μm; the diameter of the first opening is 50 μm to 500 μm, for example, 50 μm, 80 μm, 100 μm, 150 μm or 200 μm.

[0052] In one embodiment, the process of etching a portion of the thickness of the semiconductor wafer 100 using the patterned mask layer 110 as a mask to form the first opening 120 in the semiconductor wafer 100 at the bottom of the mask opening 111 includes a Bosch process.

[0053] Reference below Figure 5a to Figure 5e The preparation process of the first opening 120 is described in detail.

[0054] The Bosch process includes: step S31: reference Figure 5a , using the patterned mask layer 110 as a mask to form a plurality of initial openings A in the semiconductor wafer 100; step S32: referring to Figure 5b , forming a protective layer B on the side wall surface and the bottom surface of the initial opening A; step S33: referring to Figure 5c , etching and removing the protective layer B on the bottom surface of the initial opening A; Step S34: After performing step S33, refer to Figure 5d , using the patterned mask layer 110 and the remaining protective layer B as masks to etch the semiconductor wafer 100 at the bottom of the initial opening A, so that the depth of the initial opening A is deepened; step S35: repeating steps S32 to S34 until the initial opening forms a first opening 120 with a target depth (reference Figure 5e ); Step S36: removing the protective layer B.

[0055] The steps of performing step S32 once, step S33 once, and step S34 once constitute one cycle.

[0056] It should be noted that Figure 5a One first opening 120 is shown schematically, but it does not represent the actual number of first openings 120. In the actual forming process, a plurality of first openings 120 are formed.

[0057] Both step S31 and step S34 adopt an isotropic plasma etching process. In step S31 and step S34, the parameters of the isotropic plasma etching process include: the chamber pressure is 0.3Pa to 10Pa, the gases used include SF6, O2 and Ar, the flow rate of SF6 is 5sccm to 50sccm, the flow rate of O2 is 5sccm to 100sccm, the flow rate of Ar is 0sccm to 100sccm, the temperature is 0℃ to 70℃, the source RF power is 30W to 10000W, and the duration is 0.1s to 1min.

[0058] In one embodiment, the etching depth of step S31 is 10 nanometers to 10 micrometers; the etching depth of step S34 is 10 nanometers to 10 micrometers.

[0059] In one embodiment, steps S32 to S34 are repeated 1 to 1000 times, for example, 1, 5, 10, 50, 100, 200, 300, 500 or 1000 times.

[0060] In one embodiment, in step S2, the process for forming the protective layer B includes a plasma vapor chemical deposition process, and the parameters include: the chamber pressure is 0.3Pa~10Pa, the gases used include C4F8 and O2, the flow rate of C4F8 is 5sccm~50sccm, the flow rate of O2 is 5sccm~100sccm, the temperature is 0℃~70℃, the source RF power is 30W~10000W, and the time is 0.1s~1min.

[0061] In one embodiment, in step S33, the parameters for etching and removing the protective layer on the bottom surface include: the chamber pressure is 0.3Pa~10Pa, the gases used include SF6, O2 and Ar, the flow rate of SF6 is 5sccm~50sccm, the flow rate of O2 is 5sccm~100sccm, the flow rate of Ar is 0sccm~100sccm, the temperature is 0℃~70℃, the source RF power is 30W~10000W, the bias RF power is 10W~2000W, and the time is 0.1s~1min.

[0062] In one embodiment, the material of the protection layer includes polytetrafluoroethylene.

[0063] refer to Figure 6 , a protection film 130 is formed on the side wall surface and the bottom surface of the first opening 120 .

[0064] In one embodiment, the material of the protection film 130 includes polytetrafluoroethylene.

[0065] In one embodiment, the process of forming the protective film 130 includes a plasma vapor chemical deposition process, and the parameters include: the chamber pressure is 0.3Pa~10Pa, the gases used include C4F8 and O2, the flow rate of C4F8 is 5sccm~50sccm, the flow rate of O2 is 5sccm~100sccm, the temperature is 0℃~70℃, the source RF power is 30W~10000W, and the time is 1min~1h.

[0066] In one embodiment, the protective film 130 has a thickness of 0.1 μm to 5 μm.

[0067] refer to Figure 7 , Figure 8 and Fig. 9 , the protective film 130 and the semiconductor wafer 100 at the bottom of the first opening 120 are feature etched. In the feature etching, the etching rate of the central area of ​​the protective film 130 on the bottom surface of the first opening 120 is greater than the etching rate of the peripheral area of ​​the protective film 130 on the bottom surface of the first opening 120, and the etching depth of the central area of ​​the semiconductor wafer 100 at the bottom of the first opening 120 is greater than the etching depth of the peripheral area of ​​the semiconductor wafer 100 at the bottom of the first opening 120, so as to form a V-shaped opening 140 connected to the side wall of the first opening 120 in the semiconductor wafer 100 at the bottom of the first opening 120.

[0068] In one embodiment, the feature etching is a plasma etching process, and the parameters include: the chamber pressure is 0.3Pa~10Pa, the gases used include SF6, O2 and Ar, the flow rate of SF6 is 5sccm~50sccm, the flow rate of O2 is 5sccm~100sccm, the flow rate of Ar is 0sccm~100sccm, the temperature is 0℃~70℃, the source RF power is 30W~10000W, the bias RF power is 10W~2000W, and the time is 10s~30min.

[0069] By setting the etching parameters of the feature etching, the protective film 130 on the bottom surface of the first opening 120 is gradually etched from the center to the periphery, and the semiconductor wafer 100 corresponding to the etched area is etched during the etch process. The center position of the semiconductor wafer 100 that is first etched has a larger amount of etching on the material of the semiconductor wafer 100 than the edge position that is etched later, and finally a V-shaped opening 140 is etched.

[0070] refer to Fig.10 , remove the patterned mask layer 110 and the remaining protection film 130.

[0071] The protection film 130 of the patterned mask layer 110 is removed by a cleaning process.

[0072] refer to Fig.11, illustrating the actual shapes of the first opening 120 and the V-shaped opening 140.

[0073] Another embodiment of the present invention further provides a method for preparing a cell culture plate, comprising: providing a semiconductor mold, the semiconductor mold being formed by the method for preparing the semiconductor mold of the above embodiment; forming a transition mold on the semiconductor mold by using a reverse molding process, the transition mold comprising a base layer 200 (reference Fig.12 ) and a protrusion located on a portion of the surface of the base layer 200, wherein the protrusion includes a first protrusion area 220 corresponding to the first opening (reference Fig.12 ) and the second raised area 230 corresponding to the V-shaped opening (reference Fig.12 ); demolding the transition mold and the semiconductor mold; after demolding the transition mold and the semiconductor mold, a cell culture plate is formed on the transition mold by a reverse molding process, wherein the cell culture plate has a target opening, and the target opening includes a second opening 320 corresponding to the first raised area 220 (reference Fig.13 ) and the third opening 330 corresponding to the second raised area 230 (reference Fig.13 ); Demolding and separating the transition mold and the cell culture plate.

[0074] The preparation method of the cell culture plate also includes: before forming a transition mold on the semiconductor mold by using the reverse molding process, forming a first demolding layer on the side wall of the first opening and the inner wall surface of the V-shaped opening and the surface of the semiconductor mold between adjacent first openings; in the step of forming the transition mold on the semiconductor mold by using the reverse molding process, the transition mold covers the first demolding layer; after demolding and separating the transition mold from the semiconductor mold and before forming a cell culture plate on the transition mold by using the reverse molding process, forming a second demolding layer on the surface of the protrusion and the base surface of the side of the protrusion; in the step of forming the cell culture plate on the transition mold by using the reverse molding process, the cell culture plate covers the second demolding layer.

[0075] The process for forming the first release layer and the second release layer is a plasma vapor chemical deposition process, and the parameters include: the chamber pressure is 0.3Pa~10Pa, the gases used include C4F8 and O2, the flow rate of C4F8 is 5sccm~50sccm, the flow rate of O2 is 5sccm~100sccm, the temperature is 0℃~70℃, the source RF power is 30W~10000W, and the time is 1s~5min.

[0076] The method for forming a transition mold on the semiconductor mold by using a reverse molding process includes: providing a first molding solution; coating the first molding solution on the side walls of the first opening and the inner wall surface of the V-shaped opening and the surface of the semiconductor mold between adjacent first openings; and curing the first molding solution to form a transition mold.

[0077] In one embodiment, the first molding solution includes silicone rubber liquid and curing agent; the mass ratio of silicone rubber liquid to curing agent is 6:1 to 12:1.

[0078] In one embodiment, the parameters for curing the first molding solution include: a curing temperature of 60 degrees Celsius to 100 degrees Celsius, and a curing time of 30 minutes to 90 minutes.

[0079] The method for forming a cell culture plate on the transition mold by using a reverse molding process comprises: providing a second molding solution; coating the second molding solution on the surface of the protrusion and the base layer on the side of the protrusion; and curing the second molding solution to form a cell culture plate.

[0080] In one embodiment, the second molding solution includes silicone rubber liquid and curing agent; the mass ratio of silicone rubber liquid to curing agent is 6:1 to 12:1.

[0081] In one embodiment, the parameters for curing the second molding solution include: a curing temperature of 60 degrees Celsius to 100 degrees Celsius, and a curing time of 30 minutes to 90 minutes.

[0082] In one embodiment, the material of the transition mold is polydimethylsiloxane, and the material of the cell culture plate is polydimethylsiloxane. The material of the cell culture plate is non-toxic to cells and is conducive to the cultivation of cells by the cell culture plate.

[0083] The semiconductor mold of the present invention can be used not only as a mold for preparing cell culture plates, but also in other fields such as biology and medicine, such as microfluidics technology.

[0084] Obviously, the above embodiments are merely examples for the purpose of clear explanation, and are not intended to limit the implementation methods. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. The obvious changes or modifications derived therefrom are still within the scope of protection of the invention.

Claims

1. A method for preparing a semiconductor mold, wherein the semiconductor mold is used to prepare a cell culture plate, characterized in that: include: Providing semiconductor wafers; Forming a patterned mask layer on one side surface of the semiconductor wafer, wherein the patterned mask layer has a plurality of mask openings arranged in an array; Using the patterned mask layer as a mask, etching a portion of the thickness of the semiconductor wafer to form a first opening in the semiconductor wafer at the bottom of the mask opening; The depth of the first opening is 10µm~100µm; The diameter of the first opening is 50µm~500µm; A protective film is formed on the side wall surface and the bottom surface of the first opening; the thickness of the protective film is 0.1µm~5µm; The material of the protective film includes polytetrafluoroethylene; The protective film and the semiconductor wafer at the bottom of the first opening are subjected to feature etching, wherein the etching rate of the central area of ​​the protective film on the bottom surface of the first opening is greater than the etching rate of the peripheral area of ​​the protective film on the bottom surface of the first opening, and the etching depth of the central area of ​​the semiconductor wafer at the bottom of the first opening is greater than the etching depth of the peripheral area of ​​the semiconductor wafer at the bottom of the first opening, so as to form a V-shaped opening connected to the side wall of the first opening in the semiconductor wafer at the bottom of the first opening; wherein the feature etching is a plasma etching process, and the parameters include: the chamber pressure is 0.3Pa~10Pa, the gases used include SF6, O2 and Ar, the flow rate of SF6 is 5sccm~50sccm, the flow rate of O2 is 5sccm~100sccm, the flow rate of Ar is 0sccm~100sccm, the temperature is 0℃~70℃, the source RF power is 30W~10000W, the bias RF power is 10W~2000W, and the time is 10s~30min; After the V-shaped opening is formed, the patterned mask layer and the remaining protection film are removed.

2. The method for preparing a semiconductor mold according to claim 1, characterized in that: The material of the semiconductor wafer includes single crystal silicon.

3. The method for preparing a semiconductor mold according to claim 2, characterized in that: The process of etching a portion of the thickness of the semiconductor wafer using the patterned mask layer as a mask to form a first opening in the semiconductor wafer at the bottom of the mask opening includes a Bosch process.

4. The method for preparing a semiconductor mold according to claim 1, characterized in that: The process of forming the protective film includes a plasma vapor chemical deposition process, and the parameters include: the chamber pressure is 0.3Pa~10Pa, the gases used include C4F8 and O2, the flow rate of C4F8 is 5sccm~50sccm, the flow rate of O2 is 5sccm~100sccm, the temperature is 0℃~70℃, the source RF power is 30W~10000W, and the time is 1min~1h.

5. A method for preparing a cell culture plate, characterized in that: include: A semiconductor mold is provided, wherein the semiconductor mold is formed by the semiconductor mold preparation method according to any one of claims 1 to 4; A transition mold is formed on the semiconductor mold by using a reverse molding process, wherein the transition mold includes a base layer and a protrusion located on a portion of the surface of the base layer, wherein the protrusion includes a first protrusion area corresponding to the first opening and a second protrusion area corresponding to the V-shaped opening; Demolding and separating the transition mold and the semiconductor mold; After the transition mold is demoulded and separated from the semiconductor mold, a cell culture plate is formed on the transition mold by using a reverse molding process, wherein the cell culture plate has a target opening, and the target opening includes a second opening corresponding to the first convex area and a third opening corresponding to the second convex area; De-mold the transition mold from the cell culture plate.

6. The method for preparing a cell culture plate according to claim 5, characterized in that: Also includes: Before forming a transition mold on the semiconductor mold by using a reverse molding process, a first demoulding layer is formed on the side walls of the first openings and the inner wall surfaces of the V-shaped openings and the surface of the semiconductor mold between adjacent first openings; in the step of forming a transition mold on the semiconductor mold by using a reverse molding process, the transition mold covers the first demoulding layer; After the transition mold is demolded and separated from the semiconductor mold, and before the cell culture plate is formed on the transition mold by the reverse molding process, a second demolding layer is formed on the surface of the protrusion and the base surface of the side of the protrusion; in the step of forming the cell culture plate on the transition mold by the reverse molding process, the cell culture plate is covered with the second demolding layer.

7. The method for preparing a cell culture plate according to claim 6, characterized in that: The process for forming the first release layer and the second release layer is a plasma vapor chemical deposition process, and the parameters include: the chamber pressure is 0.3Pa~10Pa, the gases used include C4F8 and O2, the flow rate of C4F8 is 5sccm~50sccm, the flow rate of O2 is 5sccm~100sccm, the temperature is 0℃~70℃, the source RF power is 30W~10000W, and the time is 1s~5min.

8. The method for preparing a cell culture plate according to claim 5 or 6, characterized in that: The method for forming a transition mold on the semiconductor mold by using a reverse molding process comprises: providing a first molding solution; coating the first molding solution on the side walls of the first openings and the inner wall surfaces of the V-shaped openings and the surface of the semiconductor mold between adjacent first openings; curing the first molding solution to form a transition mold; The first molding solution includes silicone rubber liquid and curing agent; The mass ratio of silicone rubber liquid to curing agent is 6:1~12:1; The parameters for curing the first molding solution include: a curing temperature of 60 degrees Celsius to 100 degrees Celsius, and a curing time of 30 minutes to 90 minutes.

9. The method for preparing a cell culture plate according to claim 5 or 6, characterized in that: The method for forming a cell culture plate on the transition mold by using a reverse molding process comprises: providing a second molding solution; coating the second molding solution on the surface of the protrusion and the base layer on the side of the protrusion; curing the second molding solution to form a cell culture plate; The second molding solution includes silicone rubber liquid and a curing agent; The mass ratio of silicone rubber liquid to curing agent is 6:1~12:1; The parameters for curing the second molding solution include: a curing temperature of 60 degrees Celsius to 100 degrees Celsius, and a curing time of 30 minutes to 90 minutes.

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