Semiconductor structure and semiconductor structure forming method

Abstract

Embodiments of the present invention relate to the technical field of semiconductors, and provide a semiconductor structure and a semiconductor structure forming method. The semiconductor structure forming method comprises: providing a substrate; forming an initial photoresist layer on the substrate, and patterning the initial photoresist layer to form a photoresist layer, wherein the photoresist layer is provided with a plurality of positioning openings extending through the thickness of the photoresist layer; forming an initial target layer, wherein the initial target layer is located on the surface of the photoresist layer away from the substrate, and the initial target layer fills the positioning openings; removing the initial target layer higher than the top surface of the photoresist layer, and using the initial target layer located in the positioning openings as a target layer; and removing the photoresist layer. The implementation of the present disclosure is at least conducive to solving the problem of incapability of forming a patterned target layer due to the incompatibility between the material of a target layer and the material of a photoresist layer.

Description

A semiconductor structure and its formation method Technical Field

[0001] This invention relates to the field of semiconductor technology, and in particular to a semiconductor structure and a method for forming the same. Background Technology

[0002] With the rapid development of semiconductor technology, in order to make semiconductor devices have better performance, more requirements have been placed on the material properties of semiconductor devices. Some potential materials have outstanding physical and chemical properties. Therefore, these potential materials are more suitable for use in semiconductor devices. For example, organic materials have excellent elasticity, so the vibration amplitude of organic materials is much larger than that of inorganic materials such as polycrystalline silicon. They are more suitable as vibration films. In addition, organic materials have excellent moisture resistance and can also serve as protective layers.

[0003] However, because the properties of the potential material are similar to those of the photoresist, the two materials are incompatible, making it difficult to integrate the potential material into the semiconductor manufacturing process. Summary of the Invention

[0004] The present invention provides a semiconductor structure and a method for forming the same, which at least helps to solve the problem of the inability to form a patterned target layer due to the incompatibility between the material of the target layer and the material of the photoresist layer.

[0005] One aspect of this invention provides a method for forming a semiconductor structure, comprising: providing a substrate; forming an initial photoresist layer on the substrate; patterning the initial photoresist layer to form a photoresist layer, wherein the photoresist layer has a plurality of positioning openings penetrating the thickness of the photoresist layer; forming an initial target layer, wherein the initial target layer is located on the surface of the photoresist layer away from the substrate, and the initial target layer fills the positioning openings; removing the initial target layer above the top surface of the photoresist layer, wherein the initial target layer located at the positioning openings serves as the target layer; and removing the photoresist layer.

[0006] In some embodiments, the material of the target layer includes organic materials.

[0007] In some embodiments, after forming the initial target layer, the method further includes: planarizing the surface of the initial target layer away from the substrate; removing the initial target layer above the top surface of the photoresist layer includes: etching away a portion of the thickness of the initial target layer until the top surface of the photoresist layer is exposed.

[0008] In some embodiments, the process for forming the initial target layer includes: coating process, hot pressing process, rolling process, electroplating process, or deposition process.

[0009] In some embodiments, removing the initial target layer above the top surface of the photoresist layer includes: using a dry etching process to remove the initial target layer above the top surface of the photoresist layer.

[0010] In some embodiments, removing the photoresist layer includes: removing the photoresist layer using a first etching process, wherein the etching rate of the photoresist layer is greater than the etching rate of the target layer in the first etching process.

[0011] In some embodiments, providing a substrate includes: providing an initial substrate; forming a functional layer on the initial substrate, wherein the initial substrate and the functional layer together constitute a substrate.

[0012] Another aspect of the present invention provides a semiconductor structure formed using the semiconductor structure formation method described in the above embodiments. The semiconductor structure includes: a substrate; a patterned target layer located on the substrate, with the target layer exposing a portion of the substrate.

[0013] The beneficial effects of the embodiments of the present invention are as follows: First, the initial photoresist layer on the substrate is etched to form a photoresist layer with positioning openings, and the target layer is formed within the positioning openings of the photoresist layer. In this way, the initial photoresist layer is avoided from being formed on the target layer, and the technical problem that the initial photoresist layer cannot be patterned due to the incompatibility between the material of the target layer and the material of the initial photoresist layer is solved. In addition, the problem that the target layer cannot be patterned due to the incompatibility between the material of the target layer and the material of the photoresist layer is solved. Attached Figure Description

[0014] One or more embodiments are illustrated by way of example with corresponding pictures in the accompanying drawings. These illustrative descriptions do not constitute a limitation on the embodiments. Unless otherwise stated, the pictures in the accompanying drawings do not constitute a limitation on scale. In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the conventional technology, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0015] Figure 1 is a schematic diagram of a semiconductor structure corresponding to an initial substrate in a semiconductor structure formation method provided by an embodiment of the present invention;

[0016] Figure 2 is a schematic diagram of the semiconductor structure corresponding to the functional layer in a semiconductor structure formation method provided by an embodiment of the present invention;

[0017] Figure 3 is a schematic diagram of the semiconductor structure corresponding to the initial photoresist in a semiconductor structure formation method provided by an embodiment of the present invention;

[0018] Figure 4 is a schematic diagram of the semiconductor structure corresponding to the photoresist layer formed in a semiconductor structure formation method provided by an embodiment of the present invention.

[0019] Figure 5 is a schematic diagram of the semiconductor structure corresponding to the initial target layer in a semiconductor structure formation method provided by an embodiment of the present invention;

[0020] Figure 6 is a schematic diagram of the semiconductor structure corresponding to the target layer in a semiconductor structure formation method provided by an embodiment of the present invention;

[0021] Figure 7 is a schematic diagram of the semiconductor structure corresponding to the removal of the photoresist layer in a semiconductor structure formation method provided by an embodiment of the present invention. Embodiments of the present invention

[0022] As is known from the background technology, potential materials are difficult to integrate into semiconductor manufacturing processes.

[0023] Specifically, if the underlying material and the photoresist are similar in material, directly forming the photoresist on the underlying material may cause the interface of the photoresist to fuse with the interface of the film layer formed by the underlying material. This results in the photoresist pattern formed after patterning the photoresist not meeting the expected requirements, and thus it is difficult to ensure the accurate patterning of the underlying material. Therefore, it is quite difficult to realize the method of directly forming the photoresist on the underlying material to pattern the underlying material.

[0024] To address the aforementioned problems, this invention provides a method for forming a semiconductor structure. First, an initial photoresist layer on a substrate is etched to form a photoresist layer with positioning openings. A target layer is then formed within these positioning openings. This avoids forming the initial photoresist layer on the target layer, solving the technical problem of inaccurate patterning of the initial photoresist layer due to material incompatibility between the target layer and the initial photoresist layer. Furthermore, it solves the problem of being unable to form a patterned target layer due to material incompatibility between the target layer and the photoresist layer.

[0025] To make the objectives, technical solutions, and advantages of this invention clearer, the various embodiments of this invention will be described in detail below with reference to the accompanying drawings. However, those skilled in the art will understand that many technical details have been provided in the various embodiments of this invention to facilitate a better understanding of the invention. However, the technical solutions claimed in this invention can be implemented even without these technical details and with various variations and modifications based on the following embodiments.

[0026] Figures 1 to 7 are schematic diagrams of the semiconductor structures corresponding to each step of a semiconductor structure formation method provided in an embodiment of the present invention.

[0027] Referring to Figures 1 to 7, the method for forming a semiconductor structure provided in this embodiment of the invention includes: providing a substrate 100; forming an initial photoresist layer 110 on the substrate 100; patterning the initial photoresist layer 110 to form a photoresist layer 111, wherein the photoresist layer 111 has a plurality of positioning openings 112 penetrating the thickness of the photoresist layer 111; forming an initial target layer 130, wherein the initial target layer 130 is located on the surface of the photoresist layer 111 away from the substrate 100, and the initial target layer 130 fills the positioning openings 112; removing the initial target layer 130 above the top surface of the photoresist layer 111, wherein the initial target layer 130 located in the positioning openings 112 serves as a target layer 131; and removing the photoresist layer 111.

[0028] In this way, the initial photoresist layer on the substrate is first etched to form a photoresist layer with positioning openings, which realizes the precise patterning of the initial photoresist layer and ensures that the shape of the formed photoresist layer is more in line with the expected requirements. Then, the target layer is formed within the positioning openings of the photoresist layer. This avoids forming the initial target layer first and then forming the initial photoresist layer on the initial target layer. It solves the technical problem that the initial photoresist layer cannot be precisely patterned due to the incompatibility between the materials of the target layer and the photoresist layer. In addition, it solves the problem that the target layer cannot be patterned due to the incompatibility between the materials of the target layer and the photoresist layer.

[0029] The method for forming a semiconductor structure provided in the embodiments of the invention will be described in detail below with reference to the accompanying drawings.

[0030] In some embodiments, providing the substrate 100 includes: providing an initial substrate 101, forming a functional layer on the initial substrate 101, wherein the initial substrate 101 and the functional layer together constitute the substrate 100. That is, the substrate 100 can be a single-layer substrate or a substrate with a functional layer formed thereon.

[0031] Referring to Figures 1 and 2, in some embodiments, providing a substrate 100 includes: providing an initial substrate 101, forming a functional layer on the initial substrate 101, the functional layer including a first functional layer 102 and a second functional layer 103 sequentially stacked along a direction away from the initial substrate 101.

[0032] It should be noted that in other embodiments, the functional layer may also include a first functional layer, a second functional layer and a third functional layer stacked sequentially along the direction away from the initial substrate 101. The present invention does not limit the number of functional layers on the initial substrate 101. In practical applications, the corresponding number of functional layers can be set according to the needs of the semiconductor device.

[0033] In some embodiments, the initial substrate 101 is a silicon substrate. In other embodiments, the material of the initial substrate 101 may also be a material that can directly enter the manufacturing process to produce semiconductor devices. For example, the material of the initial substrate 101 may be at least one of silicon-on-insulator (SOI), germanium, silicon carbide, gallium arsenide, or sapphire.

[0034] In some embodiments, the functional layer can be any type of piezoelectric material. In some examples, the material of the functional layer may include at least one of lead zirconate titanate piezoelectric ceramic, aluminum nitride, scandium aluminum nitride, potassium sodium niobate, barium titanate, or zinc oxide.

[0035] Referring to Figures 3 and 4, an initial photoresist layer 110 is formed on the substrate 100. In some examples, the step of forming the initial photoresist layer 110 may include: forming the initial photoresist layer by spin coating, exposing the initial photoresist layer to a photomask so that the initial photoresist layer in the target area is dissolved in the developer and removed, and the remaining initial photoresist layer outside the target area is used as photoresist layer 111. In this way, a photoresist layer 111 with positioning openings 112 can be formed. It should be noted that the positioning openings 112 correspond to the target layer 131 formed subsequently.

[0036] Referring to Figure 5, an initial target layer 130 is formed. The initial target layer 130 is located on the surface of the photoresist layer 111 away from the substrate 100, and the initial target layer 130 fills the positioning opening 112. It should be noted that the initial target layer 130 should be thick enough to completely bury the photoresist layer 110.

[0037] In some embodiments, the initial target layer 130 may be a dry film, liquid, paste, or any other type of film layer.

[0038] In some embodiments, the process of forming the initial target layer 130 includes: coating process, hot pressing process, rolling process, electroplating process, or deposition process.

[0039] In some embodiments, the material of the initial target layer 130 is an organic material.

[0040] It should be noted that, because the photoresist layer 111 has positioning openings 112, in some embodiments, after the initial target layer 130 is formed, the top surface of the initial target layer 130 away from the substrate 100 has a different height; that is, the top surface of the initial target layer 130 away from the substrate 100 is not a flat surface. To avoid the uneven surface of the initial target layer 130 negatively affecting the morphology of the subsequently formed target layer 131, in some embodiments, after forming the initial target layer 130, a planarization process is further performed on the surface of the initial target layer 130 away from the substrate 100 to make the surface of the initial target layer 130 away from the substrate 100 a smooth surface.

[0041] In some embodiments, a chemical mechanical polishing process may be used to planarize the surface of the initial target layer 130 away from the substrate 100.

[0042] In some embodiments, referring to Figures 5 and 6, removing the initial target layer 130 above the top surface of the photoresist layer 111 includes: etching away a portion of the initial target layer 130 until the top surface of the photoresist layer 111 is exposed. That is, the initial target layer 130 is etched using the photoresist layer 111 as an etch stop layer to remove the initial target layer 130 located on the top surface of the photoresist layer 111 away from the substrate 100, retaining the initial target layer 130 located within the positioning opening 112 as the target layer 131. In this way, a patterned target layer 131 can be formed. Furthermore, in the process of forming the patterned target layer 131, the photoresist layer 111 with the positioning opening 112 is cleverly formed first, and then the target layer 131 is formed in a specific area of ​​the substrate 100 using the positioning opening 112. This solves the problem that the initial target layer 130 patterning process cannot be performed because the material properties of the initial target layer 130 are similar to those of the photoresist layer 111, allowing for more flexible and wider material selection for semiconductor devices.

[0043] In some embodiments, removing the initial target layer 130 above the top surface of the photoresist layer 111 includes using a dry etching process to remove the initial target layer 130 above the top surface of the photoresist layer 111. It is understood that in other embodiments, a wet etching process may also be used to remove the initial target layer 130 above the top surface of the photoresist layer 111.

[0044] Referring to Figures 5 and 6, after removing the initial target layer 130 that is above the top surface of the photoresist layer 111, the remaining initial target layer 130 located in the positioning opening 112 is taken as the target layer 131; referring to Figure 7, the photoresist layer 111 is removed.

[0045] In some embodiments, the target layer 131 is made of organic materials. Organic materials have excellent elasticity, resulting in a much larger vibration amplitude than inorganic materials such as polycrystalline silicon, making them more suitable as vibrating films. Furthermore, organic materials have excellent moisture resistance and can act as protective layers. The semiconductor structure formation method provided in this embodiment can form a patterned target layer 131 made of organic materials. Using organic materials to form semiconductor devices is beneficial for improving the performance of semiconductor devices.

[0046] In some embodiments, removing the photoresist layer 111 includes: removing the photoresist layer 111 using a first etching process, wherein the etching rate of the photoresist layer 111 is greater than the etching rate of the target layer 131. Removing the photoresist layer 111 using a first etching process with a higher etching rate avoids damage to the target layer 131.

[0047] In some embodiments, the first etching process includes a wet etching process.

[0048] In some embodiments, the target layer is made of PDMS (Polydimethylsiloxane), and the etching liquid for the first etching process includes acetone. This is because most photoresist layers are soluble in acetone, but PDMS is insoluble in propanol.

[0049] In the semiconductor structure formation method provided in the above embodiments, a photoresist layer 111 with positioning openings 112 is first formed, and then a target layer 131 is formed within the positioning openings 112 of the photoresist layer 111. This solves the problem of the incompatibility between the materials of the target layer 131 and the photoresist layer 111, which prevents the formation of a patterned target layer 131. By eliminating the need for conventional photolithography processes to define the pattern, the material selection for semiconductor devices can be more flexible and broader. Furthermore, after forming the target layer 131 within the positioning openings 112, the photoresist layer 111 is selectively removed using a solvent with a higher etching rate, which helps to avoid damage to the target layer 131 during the removal of the photoresist layer 111.

[0050] Another aspect of the present invention provides a semiconductor structure, which is formed using the semiconductor structure formation method described in the above embodiments. It should be noted that the parts that are the same as or corresponding to the foregoing embodiments can be referred to the foregoing embodiments, and will not be repeated hereafter.

[0051] Referring to Figure 7, the semiconductor structure includes: a substrate 100; and a patterned target layer 131 located on the substrate 100, with the target layer 131 exposing a portion of the substrate 100.

[0052] In some embodiments, the substrate 100 includes an initial substrate 101 and a functional layer located on the initial substrate 101.

[0053] In some embodiments, the functional layer includes a first functional layer 102 and a second functional layer 103 that are sequentially stacked along a direction away from the initial substrate 101.

[0054] It should be noted that in other embodiments, the functional layer may also include a first functional layer, a second functional layer and a third functional layer stacked sequentially along the direction away from the initial substrate 101. The present invention does not limit the number of functional layers on the initial substrate 101. In practical applications, the corresponding number of functional layers can be set according to the needs of the semiconductor device.

[0055] In some embodiments, the initial substrate 101 is a silicon substrate. In other embodiments, the material of the initial substrate 101 may also be a material that can directly enter the manufacturing process to produce semiconductor devices. For example, the material of the initial substrate 101 may be at least one of silicon, germanium, silicon carbide, gallium arsenide, or sapphire on an insulating substrate.

[0056] In some embodiments, the material of the target layer 131 may be parylene or other polymers.

[0057] The semiconductor structure provided by the present invention is formed by the semiconductor structure formation method provided in the above embodiments of the present invention. In the semiconductor structure provided by the present invention, the target layer can be a material with excellent properties that is similar to that of the photoresist layer. Therefore, it is possible to form a semiconductor structure using a material with excellent properties, and then form a corresponding semiconductor device using the semiconductor structure, which is beneficial to improving the performance of the semiconductor device.

[0058] Those skilled in the art will understand that the above-described embodiments are specific examples of implementing the present invention, and in practical applications, various changes in form and detail may be made without departing from the spirit and scope of the present invention. Any person skilled in the art can make their own variations and modifications without departing from the spirit and scope of the present invention.

Claims

1. A method for forming a semiconductor structure, comprising: Provide a base; An initial photoresist layer is formed on the substrate, and the initial photoresist layer is patterned to form a photoresist layer, wherein the photoresist layer has a plurality of positioning openings that penetrate the thickness of the photoresist layer; An initial target layer is formed, the initial target layer being located on the surface of the photoresist layer away from the substrate, and the initial target layer filling the positioning opening; Remove the initial target layer that is above the top surface of the photoresist layer, and use the initial target layer located at the positioning opening as the target layer; Remove the photoresist layer.

2. The method of forming a semiconductor structure of claim 1, wherein, The target layer is made of organic materials.

3. The method of forming a semiconductor structure of claim 1, wherein, After forming the initial target layer, the method further includes: planarizing the surface of the initial target layer that is away from the substrate; The removal of the initial target layer above the top surface of the photoresist layer includes: etching away a portion of the thickness of the initial target layer until the top surface of the photoresist layer is exposed.

4. The method of forming a semiconductor structure according to claim 1 or 3, wherein, The process for forming the initial target layer includes: coating process, hot pressing process, rolling process, electroplating process, or deposition process.

5. The method of forming a semiconductor structure according to claim 1 or 3, wherein, The removal of the initial target layer above the top surface of the photoresist layer includes: removing the initial target layer above the top surface of the photoresist layer using a dry etching process.

6. The method of forming a semiconductor structure of claim 1, wherein, The removal of the photoresist layer includes: removing the photoresist layer using a first etching process, wherein the etching rate of the photoresist layer is greater than the etching rate of the target layer under the first etching process.

7. The method of forming a semiconductor structure of claim 1, wherein, Providing the substrate includes: providing an initial substrate, forming a functional layer on the initial substrate, wherein the initial substrate and the functional layer constitute the substrate.

8. A semiconductor structure, said semiconductor structure being formed using the semiconductor structure forming method according to any one of claims 1 to 7, said semiconductor structure comprising: Base; A graphical target layer, the target layer being located on the substrate, and the target layer exposing a portion of the substrate.

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