Substrate processing method, substrate, photolithography method and semiconductor device

Abstract

The present application provides a substrate processing method, a substrate, a photolithography method and a semiconductor device, and relates to the field of semiconductor device manufacturing technology. The substrate processing method includes: bombarding the surface of the substrate with an ion beam to form a surface to be processed including a chemical bond breaking area, the chemical bond breaking area includes multiple active sites formed by chemical bond breaking, the material of the substrate is a hydrophilic material, and the hydrophilic material includes at least one of silicon dioxide, sapphire, silicon, silicon carbide, silicon nitride, gallium nitride, and aluminum nitride; attaching an adhesive gas to the surface to be processed to form a hydrophobic surface, the hydrophobic surface is used to adhere to the photoresist, the adhesive gas includes non-polar molecules, and the non-polar molecules combine with the active sites to form a hydrophobic surface. The embodiment of the present application can effectively improve the adhesion of the photoresist on the substrate, reduce the possibility of drifting or side drilling in subsequent processing, thereby improving the photolithography effect, avoiding the occurrence of semiconductor processing failures, and reducing production costs.

Description

Technical Field

[0001] The present application relates to the field of semiconductor manufacturing technology, and in particular, to a substrate processing method, a substrate, a photolithography method and a semiconductor device. Background Art

[0002] The photolithography process is an important part of the semiconductor device processing field. Among them, the coating of photoresist is a key step, and one of the core evaluation criteria of the process is the adhesion of the photoresist on the substrate. However, the surface of substrates such as silicon dioxide and sapphire is hydrophilic, and has poor affinity for the non-polar or low-polar resin molecules of the photoresist, resulting in poor adhesion of the photoresist, causing "resin floating" in the subsequent development step, serious side drilling in the wet etching process, and other problems, reducing the photolithography effect and even causing semiconductor processing failure. Summary of the invention

[0003] The embodiments of the present application provide a substrate processing method, a substrate, a photolithography method and a semiconductor device, which can solve the problem that the existing photoresist has poor adhesion, which easily affects subsequent processing, reduces the photolithography effect, and even causes semiconductor processing failure.

[0004] In order to achieve this purpose, the embodiments of the present application provide the following solutions.

[0005] According to one aspect of an embodiment of the present application, a substrate processing method is provided, comprising:

[0006] Bombarding the surface of the substrate with an ion beam to form a surface to be processed including a chemical bond breaking region, wherein the chemical bond breaking region includes a plurality of active sites formed by chemical bond breaking, wherein the substrate is made of a hydrophilic material, and the hydrophilic material includes at least one of silicon dioxide, sapphire, silicon, silicon carbide, silicon nitride, gallium nitride, and aluminum nitride;

[0007] The adhesive gas is attached to the surface to be processed to form a hydrophobic surface, and the hydrophobic surface is used to adhere to the photoresist. The adhesive gas includes non-polar molecules, and the non-polar molecules are combined with the active sites to form the hydrophobic surface.

[0008] In a possible implementation, bombarding the surface of the substrate with an ion beam includes:

[0009] The substrate surface is bombarded with an Ar ion beam for a first preset time to form a chemical bond breaking region on the surface to be processed.

[0010] In a possible implementation, the first preset time and the parameters of the ion beam bombardment are determined according to the type of the substrate and the conditions for breaking chemical bonds on the surface of the substrate.

[0011] In a possible implementation, the first preset time is 30 seconds, and the parameters of ion beam bombardment include: ion beam voltage 500V, ion beam current 300mA, RF power 350W, and incident angle 110 degrees.

[0012] In a possible implementation, attaching the adhesive gas to the surface to be processed includes:

[0013] placing the substrate having the surface to be processed in the space formed by the adhesive gas;

[0014] The substrate is treated at high temperature for a second preset time to form the hydrophobic surface.

[0015] In a possible implementation, the adhesive gas is HMDS, the second preset time is 60 seconds, and the temperature for processing the substrate is 150° C.

[0016] According to one aspect of an embodiment of the present application, a substrate is provided, wherein at least one side of the substrate is provided with a hydrophobic surface, and the hydrophobic surface is formed by the substrate processing method as described above.

[0017] According to one aspect of an embodiment of the present application, a photolithography method is provided, the method comprising:

[0018] forming a patterned photoresist mask based on a hydrophobic surface of a substrate, the substrate comprising the substrate as described above;

[0019] The substrate is etched to obtain a target product.

[0020] In a possible implementation, etching the substrate includes:

[0021] The substrate is etched for a third preset time using a solution of a predetermined concentration, and the photoresist mask on the substrate is removed using acetone.

[0022] According to one aspect of an embodiment of the present application, a semiconductor device is provided. The semiconductor device includes a target product, and the target product is obtained by the photolithography method as described above.

[0023] The beneficial effects of the technical solution provided by the embodiment of the present application are:

[0024] The substrate processing method provided in the embodiment of the present application includes bombarding the surface of the substrate with an ion beam to form a surface to be processed including a chemical bond breaking area, the chemical bond breaking area includes multiple active sites formed by chemical bond breaking; attaching an adhesive gas to the surface to be processed to form a hydrophobic surface, the hydrophobic surface is used to adhere to the photoresist, the adhesive gas includes non-polar molecules, and the non-polar molecules combine with the active sites to form a hydrophobic surface. The embodiment of the present application can effectively improve the adhesion of the photoresist on the substrate, reduce the possibility of drifting or side drilling in subsequent processing, thereby improving the photolithography effect, avoiding the occurrence of semiconductor processing failures, and reducing production costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following is a brief introduction to the drawings required for use in describing the embodiments of the present application.

[0026] Figure 1 A flow chart of a substrate processing method provided in an embodiment of the present application;

[0027] Figure 2 A structural diagram of a substrate provided in an embodiment of the present application;

[0028] Figure 3 A flow chart of a photolithography method provided in an embodiment of the present application;

[0029] Figure 4 A flowchart of the photolithography method provided in an embodiment of the present application;

[0030] Figure 5 A structural diagram of a semiconductor device provided in an embodiment of the present application. Description of the drawings:

[0032] 1. Substrate; 2. Hydrophobic surface. DETAILED DESCRIPTION

[0033] The embodiments of the present application are described below in conjunction with the drawings in the present application. It should be understood that the implementation methods described below in conjunction with the drawings are exemplary descriptions for explaining the technical solutions of the embodiments of the present application and do not constitute a limitation on the technical solutions of the embodiments of the present application.

[0034] It will be understood by those skilled in the art that, unless specifically stated, the singular forms "one", "said", and "the" used herein may also include plural forms. It should be further understood that the terms "including" and "comprising" used in the embodiments of the present application refer to that the corresponding features can be implemented as the presented features, information, data, steps, operations, elements and / or components, but do not exclude the implementation of other features, information, data, steps, operations, elements, components and / or combinations thereof supported by the present technical field. It should be understood that when we say that an element is "connected" or "coupled" to another element, the one element may be directly connected or coupled to the other element, or it may refer to that the one element and the other element establish a connection relationship through an intermediate element. In addition, the "connection" or "coupling" used herein may include wireless connection or wireless coupling. The term "and / or" used herein indicates at least one of the items defined by the term, for example, "A and / or B" indicates that it is implemented as "A", or is implemented as "A", or is implemented as "A and B".

[0035] In order to make the objectives, technical solutions and advantages of the present invention more clear, the embodiments of the present invention will be further described in detail below with reference to the accompanying drawings.

[0036] The following describes several exemplary embodiments to illustrate the technical solutions of the embodiments of the present invention and the technical effects produced by the technical solutions of the present invention. It should be noted that the following embodiments can refer to, draw on or combine with each other, and the same terms, similar features and similar implementation steps in different embodiments will not be described repeatedly.

[0037] The present application provides a substrate processing method, a substrate, a photolithography method and a semiconductor device, aiming to solve at least one technical problem existing in the prior art.

[0038] The present application provides a substrate processing method, such as Figure 1 As shown, the substrate processing method includes:

[0039] S101: bombarding the surface of the substrate with an ion beam to form a surface to be processed including a chemical bond breaking area.

[0040] Optionally, the material of the substrate is a hydrophilic material, and the material on the top of the substrate can be silicon dioxide, silicon, sapphire, silicon carbide, silicon nitride, gallium nitride, aluminum nitride, and other types of materials that can be used in photolithography processes.

[0041] Optionally, the ion beam may be an Ar ion beam, an oxygen ion beam, a nitrogen ion beam, or other types of plasma beams that can be used to bombard the substrate to break molecular chemical bonds on the surface of the substrate.

[0042] Optionally, bombarding the surface of the substrate with an ion beam includes: bombarding the substrate surface with an Ar ion beam for a first preset time to form a chemical bond breaking region on the surface to be processed, wherein the chemical bond breaking region includes a plurality of active sites formed by chemical bond breaking. Argon gas may be filled into an ion source that emits the ion beam, and the ion source uses the argon gas to generate an Ar ion beam for bombarding the substrate surface.

[0043] Optionally, when ion beam bombardment is used, only the region on the substrate for coating the photoresist may be bombarded with an Ar ion beam to reduce the pretreatment time of the substrate.

[0044] Optionally, the first preset time and the parameters of the ion beam bombardment are determined according to the type of substrate and the conditions for breaking chemical bonds on the substrate surface. Different substrates can be set with different first preset events and different parameters. By setting the first preset time and the parameters of the ion beam bombardment, it is ensured that there are enough chemical bonds broken in the chemical bond breaking area, thereby forming a large number of active sites.

[0045] In one embodiment, the material on the top of the substrate is silicon dioxide, the first preset time is 30 seconds, and the parameters of the ion beam bombardment include: ion beam voltage 500V, ion beam current 300mA, RF power 350W, and incident angle 110 degrees. Based on the parameters, the silicon dioxide on the top of the substrate is bombarded with an Ar ion beam, so that the chemical bonds of the silicon dioxide are broken, and a large number of active sites appear, which are used for subsequent processing.

[0046] S102: Adhesive gas is attached to the surface to be processed to form a hydrophobic surface.

[0047] Optionally, the substrate may be a hydrophilic substrate, and the adhesive gas may be HMDS (hexamethyldisilane) or other gases that can combine with the substrate to enhance the adhesion of the substrate.

[0048] In one embodiment, the adhesive gas may be a gas molecule having a non-polar methyl group on the gas molecule chain.

[0049] Optionally, attaching the adhesive gas to the surface to be processed includes: placing a substrate with the surface to be processed in a space formed by the adhesive gas; and treating the substrate at high temperature for a second preset time to form a hydrophobic surface. In the process of treating the substrate at high temperature, when the adhesive gas combines with the substrate, a large number of gas molecules combine with active sites formed on the substrate, thereby being adsorbed on the surface of the substrate to form a hydrophobic surface, and by combining the gas molecules with the active sites, a sufficient amount of HDMS can be adsorbed on the substrate, thereby facilitating the improvement of the adsorption of the photoresist on the substrate.

[0050] In one embodiment, the adhesive gas may be HMDS, and the substrate may be a hydrophilic substrate with polar OH bonds formed on the surface. After the substrate surface is bombarded with an ion beam so that the substrate surface has a large number of active sites, the substrate may be placed in a space with HMDS gas, and the substrate may be subjected to high-temperature heating in the space, so that HMDS can be adsorbed on the substrate to form a hydrophobic surface.

[0051] Optionally, the adhesion gas is HMDS, the second preset time is 60 seconds, and the temperature for processing the substrate is 150°C.

[0052] In one embodiment, the substrate bombarded by the ion beam is placed in the HMDS space and treated at a temperature of 150° C., so that the HMDS not only binds to the OH groups attached to the surface of the substrate, but also binds to numerous active sites, and a large number of HMDS gas molecules are attached to the surface of the substrate, thereby forming a hydrophobic surface. The hydrophobic surface can have a strong affinity with the non-polar analytical or low-polar resin molecules in the photoresist, thereby improving the adhesion of the substrate to the photoresist.

[0053] The substrate processing method provided in the embodiment of the present application includes bombarding the surface of the substrate with an ion beam to form a surface to be processed including a chemical bond breaking region, the chemical bond breaking region includes multiple active sites formed by chemical bond breaking; attaching an adhesive gas to the surface to be processed to form a hydrophobic surface, the hydrophobic surface is used to adhere to the photoresist, and the adhesive gas includes non-polar molecules, and the non-polar molecules are combined with the active sites to form a hydrophobic surface. The embodiment of the present application can effectively improve the adhesion of the photoresist, reduce the possibility of drifting or side drilling in subsequent processing, thereby improving the photolithography effect and avoiding the occurrence of semiconductor processing failures.

[0054] According to one aspect of the embodiments of the present application, a substrate is provided, such as Figure 2 As shown, at least one side of the substrate 1 is provided with a hydrophobic surface 2, and the method for forming the hydrophobic surface 2 includes: bombarding the surface of the substrate 1 with an ion beam to form a surface to be processed including a chemical bond breaking area; attaching an adhesive gas to the surface to be processed to form the hydrophobic surface 2.

[0055] Optionally, the hydrophobic surface 2 is used to adhere to the photoresist, and the adhesive gas includes non-polar molecules.

[0056] Optionally, using an ion beam to bombard the surface of the substrate 1 includes: using an Ar ion beam to bombard the surface of the substrate 1 for a first preset time to form a chemical bond breaking area on the surface to be processed, and the chemical bond breaking area includes multiple active sites formed by chemical bond breaking.

[0057] Optionally, the first preset time and the parameters of the ion beam bombardment are determined according to the type of the substrate 1 and the conditions for breaking chemical bonds on the surface of the substrate 1 .

[0058] In one embodiment, the first preset time is 30 seconds, and the parameters of the ion beam bombardment include: ion beam voltage 500V, ion beam current 300mA, RF power 350W, and incident angle 110 degrees.

[0059] Optionally, attaching the adhesive gas to the surface to be processed includes: placing a substrate 1 having the surface to be processed in a space formed by the adhesive gas; and treating the substrate 1 at high temperature for a second preset time to form a hydrophobic surface 2 .

[0060] In one embodiment, the adhesion gas is HMDS, the second preset time is 60 seconds, and the temperature of the processed substrate 1 is 150°C.

[0061] By the above method, the substrate 1 can absorb a large amount of adhesive gas, thereby forming a hydrophobic surface 2 that can effectively absorb photoresist, avoiding the problem of photoresist "floating" and serious side drilling during wet etching, thereby effectively improving the photolithography effect of the substrate 1.

[0062] According to one aspect of an embodiment of the present application, a photolithography method is provided, such as Figure 3 , Figure 4 As shown, the photolithography method includes:

[0063] S201: forming a patterned photoresist mask based on the hydrophobic surface of the substrate.

[0064] Optionally, the substrate may include a substrate as described in the above embodiment, wherein the hydrophobic surface can be formed by bombarding the substrate surface with an Ar ion beam, thereby breaking the chemical bonds on the substrate surface and generating a large number of active sites, placing the substrate pretreated with the ion beam in a gas such as HMDS for enhancing adhesion, and performing high-temperature treatment on the substrate. The gas molecules for enhancing adhesion not only combine with the OH groups attached to the substrate surface, but also combine with numerous active sites. A large number of gas molecules are attached to the substrate surface, thereby forming a hydrophobic surface with strong hydrophobicity. The hydrophobic surface has a strong affinity for the non-polar or low-polar resin molecules of the photoresist, thereby achieving enhanced adhesion of the photoresist on the wafer substrate.

[0065] Optionally, after forming a hydrophobic surface on the substrate, an imaged photoresist mask can be formed on the substrate by yellow light area processes such as coating, pre-baking, exposure, post-baking, developing, and hardening. The photoresist is disposed on the hydrophobic surface.

[0066] Optionally, during coating, the photoresist can be coated on the hydrophobic surface of the substrate by spin coating, spray coating, dip coating or other methods.

[0067] In one embodiment, the thickness of the coated photoresist may be 3.5 μm. During pre-baking, an oven or a hot plate may be used to bake the substrate and the photoresist at 100 degrees Celsius for 105 seconds.

[0068] Optionally, the exposure method may include mask alignment exposure, step projection exposure, laser direct writing, electronic book direct writing and other exposure methods. The dose during exposure can be determined according to the selected exposure method and the type of photoresist.

[0069] In one embodiment, the exposure dose is 414 mJ / cm 2 , through this exposure method, the photoresist is controlled to form a pattern corresponding to the mask.

[0070] Optionally, after the exposure is completed, the photoresist on the substrate is post-baked. Specifically, the parameters of the post-baking may be 107° C. for 45 seconds.

[0071] Optionally, after the exposure is completed, the photoresist is developed. The development method can be any one of immersion, spraying, and stirring. The development time can be determined according to the development method, temperature, type of developer, and type of photoresist.

[0072] In one embodiment, the developing process is performed for 3 minutes.

[0073] Optionally, during the hardening operation, the photoresist may be more firmly adhered to the substrate surface by heating and baking, and the etching resistance of the photoresist may be increased.

[0074] In one embodiment, when hardening the film, the temperature is heated to 107 degrees Celsius and treated at this temperature for 60 seconds.

[0075] S202: Etching the substrate to obtain a target product.

[0076] Optionally, wet etching can be used to etch the area of ​​the substrate not covered by the photoresist mask, so that an image matching the image of the photoresist mask is formed on the substrate, thereby realizing pattern transfer. Wherein, etching the substrate includes: etching the substrate for a third preset time using a solution of a predetermined concentration, and removing the photoresist mask on the substrate using acetone.

[0077] In one embodiment, the solution used for wet etching may be a mixture of HF (hydrofluoric acid) and NH4F (ammonium fluoride). In the mixture, 49% HF aqueous solution: 40% NH4F aqueous solution = 1:6 <volume ratio>. The etching time is 2 minutes and 20 seconds. After the etching is completed, acetone is used to remove the photoresist mask on the substrate.

[0078] Optionally, when using acetone for degumming, the substrate may be first soaked in NMP (N-methyl-2-pyrrolidone), and then soaked in IPA (isopropyl alcohol), and then the remaining liquid may be removed by flushing with water and then spun dry.

[0079] Optionally, when using acetone to remove the glue thickness, the critical dimension (CD) of the image on the substrate can also be measured. If the measurement result meets the preset conditions (such as the deviation between the critical dimension and the standard dimension is less than the preset deviation threshold, the generated side drilling value does not exceed the preset value, etc.), it is determined that the target product is obtained. If not, it is determined that a processing error has occurred, and the product can be discarded or an early warning can be issued.

[0080] Optionally, the target product obtained can be used for the production of sensor chips, voltage control chips, MCU, LCD, OLED and other types of semiconductor devices. The pattern of the photoresist mask on the target product can be determined according to the circuit and shape of the semiconductor device to be produced.

[0081] The photolithography method of the present application is further demonstrated below through an embodiment.

[0082] In one embodiment, Figure 4 As shown, two substrates A and B are prepared, both of which are made of SiO2. The shapes and sizes of A and B can be exactly the same. First, the SiO2 surface of substrate A is bombarded with an Ar ion beam for 30 seconds, causing the chemical bonds on the surface of A to break and a large number of active sites to appear.

[0083] Substrate A pretreated with ion beam and substrate B not pretreated with ion beam were placed in HMDS atmosphere and treated at 150℃ for 60s to form hydrophobic surfaces on the surfaces of substrates A and B. Substrates A and B were subjected to yellow light area processes such as coating, pre-baking, exposure, post-baking, development, and hardening under the same conditions (such as using the same coating thickness / pre-baking temperature and time / exposure dose / post-baking temperature and time), so as to realize the imaging of the photoresist mask on the bottom surface.

[0084] After the imaging of the photoresist mask is completed, the substrates A and B are both subjected to wet etching treatment under the same conditions, wherein the etching time may be 2 minutes to 20 seconds, and then both are subjected to acetone de-resist treatment.

[0085] It can be measured under a microscope at 1000X: before wet etching, the photoresist mask CD of substrates A and B is 9.77μm; after etching and removing the photoresist mask, the photoresist mask CD of substrates A and B is: 10.237μm and 17.389μm, that is, substrates A and B are side-drilled by 0.503μm and 7.619μm respectively. It can be determined that the method of using Ar plasma to pre-treat the substrate and then subjecting it to high-temperature treatment with HMDS or other similar adhesion-enhancing gases before spin coating the photoresist can effectively improve the adhesion of the photoresist, and the side-drilling amount of substrate A after ion beam treatment is much lower than that of substrate B.

[0086] Based on the same inventive concept, the present application also proposes a semiconductor device, such as Figure 5 As shown, the semiconductor device includes a target product, and an image on the target product is obtained by the photolithography method described in the above embodiment.

[0087] The terms "first", "second", "third", "fourth", "1", "2", etc. (if any) in the specification and claims of this application and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the numbers used in this way can be interchanged where appropriate, so that the embodiments of the present application described herein can be implemented in an order other than that shown or described in the drawings.

[0088] It should be understood that, although each operation step is indicated by arrows in the flowchart of the embodiment of the present application, the implementation order of these steps is not limited to the order indicated by the arrows. Unless clearly stated herein, in some implementation scenarios of the embodiment of the present application, the implementation steps in each flowchart can be performed in other orders according to demand. In addition, some or all of the steps in each flowchart may include multiple sub-steps or multiple stages based on actual implementation scenarios. Some or all of these sub-steps or stages may be executed at the same time, and each sub-step or stage in these sub-steps or stages may also be executed at different times respectively. In different scenarios of execution time, the execution order of these sub-steps or stages may be flexibly configured according to demand, and the embodiment of the present application does not limit this.

[0089] The above is only an optional implementation method for some implementation scenarios of the present application. It should be pointed out that for ordinary technicians in this technical field, without departing from the technical concept of the solution of the present application, other similar implementation methods based on the technical ideas of the present application are also within the protection scope of the embodiments of the present application.

Claims

1. A substrate processing method, characterized in that: include: Bombarding the surface of the substrate with an ion beam to form a surface to be processed including a chemical bond breaking region, wherein the chemical bond breaking region includes a plurality of active sites formed by chemical bond breaking, wherein the substrate is made of a hydrophilic material, wherein the hydrophilic material includes at least one of silicon dioxide, sapphire, silicon, silicon carbide, silicon nitride, gallium nitride, and aluminum nitride, and the chemical bond breaking region corresponds to a region coated with a photoresist; The method comprises attaching an adhesive gas to the surface to be processed to form a hydrophobic surface, comprising: placing the substrate having the surface to be processed in the space formed by the adhesive gas; The substrate is treated at high temperature for a second preset time to form the hydrophobic surface, wherein the hydrophobic surface is used to adhere to the photoresist, and the adhesion gas includes non-polar molecules, and the non-polar molecules are combined with the active sites to form the hydrophobic surface.

2. The substrate processing method according to claim 1, characterized in that: The method of bombarding the surface of the substrate with an ion beam comprises: The substrate surface is bombarded with an Ar ion beam for a first preset time to form a chemical bond breaking region on the surface to be processed.

3. The substrate processing method according to claim 2, characterized in that: The first preset time and the parameters of ion beam bombardment are determined according to the type of the substrate and the conditions for breaking chemical bonds on the surface of the substrate.

4. The substrate processing method according to claim 3, characterized in that: The first preset time is 30 seconds, and the parameters of ion beam bombardment include: ion beam voltage 500V, ion beam current 300mA, RF power 350W, and incident angle 110 degrees.

5. The substrate processing method according to claim 1, characterized in that: The adhesion gas is HMDS, the second preset time is 60 seconds, and the temperature for processing the substrate is 150°C.

6. A substrate, characterized in that At least one side of the substrate is provided with a hydrophobic surface, and the hydrophobic surface is formed by the substrate processing method according to any one of claims 1 to 5.

7. A photolithography method, characterized in that: The method comprises: forming a patterned photoresist mask based on a hydrophobic surface of a substrate, the substrate comprising the substrate of claim 6; The substrate is etched to obtain a target product.

8. The photolithography method according to claim 7, characterized in that: The etching of the substrate comprises: The substrate is etched for a third preset time using a solution of a predetermined concentration, and the photoresist mask on the substrate is removed using acetone.

9. A semiconductor device, characterized in that: The semiconductor device comprises a target product, and the target product is obtained by the photolithography method according to claim 7 or 8.

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