Semiconductor device and manufacturing method thereof

Abstract

The invention provides a semiconductor device and a manufacturing method thereof, and the method comprises the steps: providing a substrate, and forming a sacrificial layer on the substrate; forming a first humidity-sensitive material layer on the sacrificial layer; patterning the first humidity-sensitive material layer to form an interdigital trench structure in the first humidity-sensitive material layer; filling an electrode material in the interdigital groove structure to form an interdigital electrode; forming a second humidity-sensitive material layer covering the first humidity-sensitive material layer and the interdigital electrode; forming an opening at least penetrating through the first humidity-sensitive material layer and the second humidity-sensitive material layer to expose the sacrificial layer; and removing part of the sacrificial layer between the interdigital electrode and the substrate through opening etching. The interdigital groove structure is formed in the first humidity-sensitive material layer, the opening at least penetrating through the first humidity-sensitive material layer and the second humidity-sensitive material layer is formed, and a part of sacrificial layer between the interdigital electrode and the substrate is removed through the opening, so that the humidity-sensitive material is in full contact with air, the sensing time of the device is shortened, the hysteresis is reduced, and the performance of the device is improved. And the sensitivity of the device is improved.

Description

Technical Field

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

[0002] Humidity sensors are widely used in aerospace, meteorological detection, industrial control, agriculture and animal husbandry, medical equipment, smart home and other fields. In recent years, miniaturization has been an important direction for the development of humidity sensors. Existing miniature humidity sensors mainly include capacitive, resistive, piezoresistive and other types. Among them, capacitive sensors are widely used in the commercial field due to their simple structure, wide detection range, high reliability, low cost, low power consumption and other advantages. In the existing humidity capacitor devices with interdigital structure design, high sensitivity and short hysteresis are required. Therefore, the capacitor devices are required to have high capacitance density, high unit humidity capacitance change and high contact ratio between humidity-sensitive materials and air.

[0003] In related technologies, in order to achieve a large capacitance change, the depth of the interdigital electrodes must be deep enough, and the filling of the moisture-sensitive material often exceeds the aspect ratio of 2:1. Limited by the filling capacity of the moisture-sensitive material and the spin coating process, for the interdigital structure with a high aspect ratio, voids will appear after the moisture-sensitive material is filled and cured, affecting the performance of the device. At the same time, in order to increase the contact area between the moisture-sensitive material and the air, it is often achieved through back cavity processes, deep silicon etching processes, etc. The process is relatively complex, and the stability of the device structure is poor.

[0004] Therefore, improvements are needed to at least partially solve the above problems. Summary of the invention

[0005] A series of simplified concepts are introduced in the Summary of the Invention section, which will be further described in detail in the Detailed Description of the Invention section. The Summary of the Invention section of this application does not mean to attempt to define the key features and essential technical features of the claimed technical solution, nor does it mean to attempt to determine the scope of protection of the claimed technical solution.

[0006] In response to the current problems, an embodiment of the present application provides a method for manufacturing a semiconductor device, including: providing a substrate, forming a sacrificial layer on the substrate; forming a first moisture-sensitive material layer on the sacrificial layer; patterning the first moisture-sensitive material layer to form an interdigitated groove structure in the first moisture-sensitive material layer; filling the interdigitated groove structure with electrode material to form interdigitated electrodes; forming a second moisture-sensitive material layer covering the first moisture-sensitive material layer and the interdigitated electrodes; forming an opening that at least passes through the first moisture-sensitive material layer and the second moisture-sensitive material layer to expose the sacrificial layer; and removing a portion of the sacrificial layer between the interdigitated electrodes and the substrate by etching through the opening.

[0007] Exemplarily, before filling the electrode material in the interdigitated groove structure to form the interdigitated electrodes, the method further includes: forming a first protective layer covering the first moisture-sensitive material layer, the bottom and sidewalls of the interdigitated groove structure.

[0008] Exemplarily, filling the electrode material in the interdigitated groove structure to form an interdigitated electrode includes: forming the electrode material covering the first protective layer and filling the interdigitated groove structure; performing a chemical mechanical polishing process to stop at the surface of the first protective layer.

[0009] Exemplarily, after forming the interdigitated electrodes and before forming the second moisture-sensitive material layer, it also includes: forming a second protective layer covering the first protective layer and the interdigitated electrodes; etching and removing the first protective layer and the second protective layer located above the first moisture-sensitive material layer, and the remaining first protective layer and the second protective layer cover the surface of the interdigitated electrodes.

[0010] Exemplarily, the method of forming the first moisture-sensitive material layer and the second moisture-sensitive material layer includes coating and curing.

[0011] Exemplarily, the first moisture-sensitive material layer and the second moisture-sensitive material layer are made of the same material.

[0012] Exemplarily, the electrode material includes at least one of the following: aluminum, copper or tungsten.

[0013] Exemplarily, the opening exposes a portion of the surface of the sacrificial layer or a portion of the surface of the substrate.

[0014] Exemplarily, the sacrificial layer includes an oxide layer.

[0015] Another aspect of the present application provides a semiconductor device, which is manufactured using the method described above.

[0016] The semiconductor device and its manufacturing method provided by the present application form an interdigitated groove structure in a first moisture-sensitive material layer, form an interdigitated electrode in the interdigitated groove structure, form a second moisture-sensitive material layer covering the interdigitated electrode, and finally form an opening that at least penetrates the first moisture-sensitive material layer and the second moisture-sensitive material layer. The sacrificial layer between the interdigitated electrode and the substrate is removed through the opening, so that the moisture-sensitive material is fully exposed to the air, thereby shortening the sensing time of the device, reducing the hysteresis, and improving the sensitivity of the device. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] By describing the embodiments of the present application in more detail in conjunction with the accompanying drawings, the above and other purposes, features and advantages of the present application will become more apparent. The accompanying drawings are used to provide a further understanding of the embodiments of the present application and constitute a part of the specification. Together with the embodiments of the present application, they are used to explain the present application and do not constitute a limitation of the present application. In the accompanying drawings, the same reference numerals generally represent the same components or steps.

[0018] In the attached figure:

[0019] Figure 1 A flowchart showing a method for manufacturing a semiconductor device according to a specific embodiment of the present application is shown;

[0020] Figure 2A-2L A cross-sectional schematic diagram of a semiconductor device obtained by sequentially implementing a method for manufacturing a semiconductor device according to a specific embodiment of the present application is shown;

[0021] Figure 3 A top view of the structure of a semiconductor device according to a specific embodiment of the present application is shown. DETAILED DESCRIPTION

[0022] In the following description, a large number of specific details are provided to provide a more thorough understanding of the present application. However, it is apparent to those skilled in the art that the present invention can be implemented without one or more of these details. In other examples, in order to avoid confusion with the present invention, some technical features well known in the art are not described.

[0023] It should be understood that the present application can be implemented in different forms and should not be construed as being limited to the embodiments presented herein. On the contrary, providing these embodiments will make the disclosure thorough and complete, and fully convey the scope of the present invention to those skilled in the art. In the accompanying drawings, the sizes and relative sizes of layers and regions may be exaggerated for clarity. The same reference numerals throughout represent the same elements.

[0024] It should be understood that when an element or layer is referred to as being "on, adjacent to, connected to or coupled to other elements or layers, it may be directly on, adjacent to, connected to or coupled to other elements or layers, or there may be intervening elements or layers. In contrast, when an element is referred to as being "directly on, directly adjacent to, directly connected to or directly coupled to other elements or layers, there may be no intervening elements or layers. It should be understood that, although the terms first, second, third, etc. may be used to describe various elements, components, regions, layers and / or parts, these elements, components, regions, layers and / or parts should not be limited by these terms. These terms are only used to distinguish one element, component, region, layer or part from another element, component, region, layer or part. Therefore, without departing from the teachings of the present invention, the first element, component, region, layer or part discussed below may be represented as a second element, component, region, layer or part.

[0025] Spatially relative terms such as "under," "below," "below," "under," "above," "above," etc., may be used herein for ease of description to describe the relationship of an element or feature shown in the figures to other elements or features. It should be understood that in addition to the orientations shown in the figures, the spatially relative terms are intended to include different orientations of the device in use and operation. For example, if the device in the accompanying drawings is flipped, then the elements or features described as "under other elements" or "under" or "under" will be oriented as "on" the other elements or features. Therefore, the exemplary terms "under" and "under" may include both upper and lower orientations. The device may be oriented otherwise (rotated 90 degrees or other orientations) and the spatial descriptors used herein are interpreted accordingly.

[0026] The purpose of the terms used herein is only to describe specific embodiments and is not intended to be limiting of the present invention. When used herein, the singular forms "one", "an" and "said / the" are also intended to include plural forms, unless the context clearly indicates otherwise. It should also be understood that the terms "consisting of" and / or "comprising", when used in this specification, determine the presence of the features, integers, steps, operations, elements and / or parts, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, parts and / or groups. When used herein, the term "and / or" includes any and all combinations of the relevant listed items.

[0027] Embodiments of the invention are described herein with reference to cross-sectional views that are schematic diagrams of ideal embodiments (and intermediate structures) of the present application. Thus, variations from the shapes shown due to, for example, manufacturing techniques and / or tolerances can be expected. Therefore, embodiments of the present application should not be limited to the specific shapes of the zones shown herein, but include shape deviations due to, for example, manufacturing. For example, an implanted region shown as a rectangle typically has rounded or curved features and / or an implant concentration gradient at its edges, rather than a binary change from an implanted region to a non-implanted region. Similarly, a buried region formed by implantation may result in some implantation in the region between the buried region and the surface through which the implantation is performed. Therefore, the regions shown in the figures are schematic in nature, and their shapes are not intended to show the actual shape of the region of the device and are not intended to limit the scope of the present application.

[0028] Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by ordinary technicians in the field of this application. It will also be understood that terms such as those defined in commonly used dictionaries should be understood to have a meaning consistent with their meaning in the context of the relevant art and / or this specification, and should not be interpreted in an ideal or overly formal sense unless expressly defined as such herein.

[0029] In order to thoroughly understand the present application, detailed steps and structures will be presented in the following description to illustrate the technical solution proposed by the present application. The preferred embodiments of the present application are described in detail below, but in addition to these detailed descriptions, the present application may also have other implementations.

[0030] In the related art, in order to achieve a large capacitance change, the depth of the interdigital electrodes needs to be deep enough, so the filling of the moisture-sensitive material often exceeds the aspect ratio of 2:1. However, due to the limitations of the filling capacity of the moisture-sensitive material and the spin coating process, for the interdigital structure with a high aspect ratio, voids will appear after the moisture-sensitive material is filled and cured, which seriously affects the performance of the device.

[0031] In order to shorten the sensing time of the device and reduce the hysteresis of the device, it is necessary to increase the contact area between the humidity sensitive material and the air. In the related technology, the air contact area of ​​the humidity sensitive material is often increased by back cavity process, deep silicon etching process, etc. These processes are relatively complex and the device structure stability is poor.

[0032] Therefore, in view of the existence of the above-mentioned technical problems, the present application embodiment proposes a method for manufacturing a semiconductor device, such as Figure 1 As shown, it mainly includes the following steps:

[0033] In step S101, a substrate is provided, and a sacrificial layer is formed on the substrate;

[0034] In step S102, a first moisture-sensitive material layer is formed on the sacrificial layer;

[0035] In step S103, the first moisture-sensitive material layer is patterned to form an interdigitated groove structure in the first moisture-sensitive material layer;

[0036] In step S104, an electrode material is filled in the interdigitated trench structure to form an interdigitated electrode;

[0037] In step S105, a second humidity-sensitive material layer covering the first humidity-sensitive material layer and the interdigital electrodes is formed;

[0038] In step S106, an opening is formed that at least penetrates the first moisture-sensitive material layer and the second moisture-sensitive material layer to expose the sacrificial layer;

[0039] In step S107 , a portion of the sacrificial layer between the interdigital electrodes and the substrate is removed by opening etching.

[0040] The manufacturing method of the semiconductor device of the embodiment of the present application takes advantage of metal hole filling by adjusting the process flow and process method, realizes narrow and deep moisture-sensitive materials between the interdigital electrodes, improves the capacitance density and relative capacitance area, and achieves the purpose of increasing the capacitance change of the device under unit humidity change and improving the sensitivity of the device. The interdigital structure is adjusted to a non-equidistant structure, and the oxide sacrificial layer below is removed through the vacancies on both sides and in the middle of the interdigital fingers, forming a structure in which the entire interdigital metal is wrapped by moisture-sensitive materials in four directions, and the upper and lower surfaces of the moisture-sensitive materials are fully in contact with the air. This shortens the device's sensing time for humidity, improves sensitivity, and does not require a back cavity process to achieve the purpose of full contact between the back and the air, thereby improving the stability of the device mechanism.

[0041] Embodiment 1

[0042] Below, reference Figure 1 as well as Figures 2A to 2L The manufacturing method of the semiconductor device of the present application is described in detail, wherein: Figure 1 A flowchart of a method for manufacturing a semiconductor device according to a specific embodiment of the present application is shown. Figures 2A to 2L A cross-sectional schematic diagram of a device obtained by sequentially implementing a method for manufacturing a semiconductor device according to a specific embodiment of the present application is shown.

[0043] Exemplarily, the method for manufacturing a semiconductor device of the present application includes the following steps:

[0044] First, step S101 is performed to provide a substrate and form a sacrificial layer on the substrate.

[0045] In one example, if Figure 2AAs shown, the material of the substrate 200 includes but is not limited to at least one of the following materials: silicon (Si), germanium (Ge), silicon germanium (SiGe), silicon carbide (SiC), carbon germanium silicon (SiGeC), indium arsenide (InAs), gallium arsenide (GaAs), indium phosphide (InP), sapphire (Sapphire) or other III / V compound semiconductors, or silicon on dielectric (SOI), stacked silicon on dielectric (SSOI), stacked silicon germanium on dielectric (S-SiGeOI), silicon germanium on dielectric (SiGeOI) and germanium on dielectric (GeOI), or double-side polished silicon wafers (Double Side Polished Wafers, DSP), ceramic substrates of aluminum oxide, quartz or glass substrates, etc. Although several examples of materials that can form the substrate 200 are described here, any material that can be used as the substrate 200 falls within the spirit and scope of the present invention.

[0046] In one example, continuing Figure 2A As shown, a sacrificial layer 201 is formed on a substrate 200. By way of example, the material of the sacrificial layer 201 may be an oxide layer, for example, silicon dioxide (SiO 2 ) and carbon-doped silicon oxide (SiOC) and other materials, but are not limited to the above examples. In addition, the sacrificial layer 201 can be formed by any suitable method known to those skilled in the art, for example, the sacrificial layer 201 can be formed by a deposition process such as chemical vapor deposition (CVD) but not limited to, specifically, low pressure chemical vapor deposition (LPVCD), atmospheric pressure chemical vapor deposition (APCVD) or plasma enhanced chemical vapor deposition (PECVD), or the sacrificial layer 201 can be formed by a high temperature furnace tube thermal oxidation process.

[0047] Next, step S102 is performed to form a first moisture-sensitive material layer on the sacrificial layer.

[0048] In one example, if Figure 2B As shown, a first moisture-sensitive material layer 202 is formed on the sacrificial layer 201. Exemplarily, the first moisture-sensitive material layer 202 may be made of known organic polymer moisture-sensitive materials, such as polyimides, polymethyl methacrylates and their derivatives, copolymers with other monomers, etc. In this embodiment, the first moisture-sensitive material layer 202 is made of polyimide.

[0049] Exemplarily, the method for forming the first moisture-sensitive material layer 202 on the sacrificial layer 201 includes coating and curing, wherein the coating may include spin coating and spray coating. Specifically, a polyimide precursor (i.e., polyamic acid material) is spin-coated on the surface of the sacrificial layer 201, and then placed in an oven for baking and imidization (i.e., curing) to form the first moisture-sensitive material layer 202 of a desired thickness.

[0050] Next, step S103 is performed to pattern the first moisture-sensitive material layer to form an interdigitated groove structure in the first moisture-sensitive material layer.

[0051] In one example, if Figure 2C As shown, the first wet-sensitive material layer 202 is patterned to form an interdigitated groove structure 203 in the first wet-sensitive material layer 202. Specifically, first, a patterned photoresist layer is formed on the surface of the first wet-sensitive material layer 202, the photoresist layer exposes the area corresponding to the interdigitated groove structure, the first wet-sensitive material layer 202 is etched using the photoresist layer as a mask, and then the photoresist layer is removed. Exemplarily, the first wet-sensitive material layer 202 can be etched using conventional etching processes such as dry etching, reactive ion etching (RIE), ion beam etching, and plasma etching to form the interdigitated groove structure 203. Of course, a hard mask layer can also be formed on the surface of the first wet-sensitive material layer 202 first, and then the pattern is transferred to the hard mask layer using the above-mentioned photoresist layer as a mask, and then the first wet-sensitive material layer 202 is etched using the hard mask layer to form the interdigitated groove structure 203, and finally the hard mask layer is removed. The above-mentioned method of forming the interdigitated groove structure is a common method in the art, and no excessive description or limitation is given here. In short, the method of forming the required interdigitated groove structure 203 in the moisture-sensitive material is within the protection scope of the present application. Exemplarily, the aspect ratio of the formed interdigitated groove structure 203 is greater than 1:1. The higher aspect ratio structure can subsequently achieve a larger capacitance change of the device and improve the sensitivity of the device. Exemplarily, the multiple interdigitated groove structures 203 are non-equidistant structures, which facilitates the subsequent formation of openings, releases the sacrificial layer 201, and allows the moisture-sensitive material to fully contact the air.

[0052] Next, step S104 is performed to fill the interdigitated trench structure with electrode material to form interdigitated electrodes.

[0053] In one example, if Figure 2DAs shown, before the electrode material is filled in the interdigitated groove structure 203, the first protective layer 204 covering the first moisture-sensitive material layer 202, the bottom and the sidewall of the interdigitated groove structure 203 is formed. Exemplarily, the material of the first protective layer 204 can be nitride, oxide or oxynitride, such as silicon nitride, silicon oxide, etc. The first protective layer 204 covering the first moisture-sensitive material layer 202, the bottom and the sidewall of the interdigitated groove structure 203 can be formed by processes such as but not limited to chemical vapor deposition (CVD) and physical vapor deposition (Physical Vapor Deposition, PVD). The formed first protective layer 204 can be used as a stop layer for subsequent chemical mechanical polishing (CMP) to protect the metal electrode formed subsequently.

[0054] In one example, if Figure 2E As shown, the electrode material 205 is filled in the interdigitated groove structure 203 to form the interdigitated electrode 2051. Exemplarily, the electrode material 205 covering the first protective layer 204 and filling the interdigitated groove structure 203 is formed, and the material of the electrode material 205 can be aluminum, copper or tungsten, etc., which is not specifically limited. The process method for forming the electrode material 205 can include physical vapor deposition (PVD) or atomic layer deposition (Atomic Layer Deposition, ALD) and other methods well known to those skilled in the art.

[0055] Exemplarily, the material of the electrode material 205 is aluminum material, and the process method for forming the electrode material 205 can use evaporation or sputtering process to fill the electrode material 205. Exemplarily, the material of the electrode material 205 is copper material, and the process method for forming the electrode material 205 can use electroplating or sputtering process to fill the electrode material 205. Exemplarily, the material of the electrode material 205 is tungsten material, and the process method for forming the electrode material 205 can use Metal-Organic Chemical Vapor Deposition (MOCVD) process to fill the electrode material 205.

[0056] In one example, if Figure 2FAs shown, a chemical mechanical polishing (CMP) process is performed to stop at the surface of the first protective layer 204, thereby forming the interdigitated electrodes 2051. Specifically, a CMP process is performed to remove the electrode material 205 outside the interdigitated groove structure 203, so as to stop at the surface of the first protective layer 204, thereby forming the interdigitated electrodes 2051. The stop endpoint of the planarization is monitored and controlled by various methods commonly used in the art, such as EPD (End point detection). Exemplarily, in the example of forming a plurality of interdigitated groove structures 203, the formed interdigitated electrodes 2051 also include a plurality.

[0057] In one example, if Figure 2G As shown, after forming the interdigital electrodes 2051, it also includes: forming a second protective layer 206 covering the first protective layer 204 and the interdigital electrodes 2051. Exemplarily, the material of the second protective layer 206 can be nitride, oxide or oxynitride, such as silicon nitride, silicon oxide, etc. The second protective layer 206 covering the first protective layer 204 and the interdigital electrodes 2051 can be formed by processes such as but not limited to chemical vapor deposition (CVD) and physical vapor deposition (Physical Vapor Deposition, PVD). The materials of the first protective layer 204 and the second protective layer 206 can be the same, for example, the materials of the first protective layer 204 and the second protective layer 206 can be silicon nitride. In other examples, the materials of the first protective layer 204 and the second protective layer 206 can be different, which is not specifically limited. The formed second protective layer 206 can protect the formed interdigital electrodes 2051.

[0058] In one example, if Figure 2H As shown, after the second protective layer 206 is formed, the first protective layer 204 and the second protective layer 206 located above the first moisture-sensitive material layer 202 are continuously etched away. The remaining first protective layer 204 and the second protective layer 206 cover the surface of the interdigital electrodes 2051. Specifically, conventional etching processes such as, but not limited to, dry etching, reactive ion etching (RIE), ion beam etching, and plasma etching may be used to remove the first protective layer 204 and the second protective layer 206 located above the first moisture-sensitive material layer 202, so that the remaining first protective layer 204 and the second protective layer 206 cover the surface of the interdigital electrodes 2051, thereby protecting the interdigital electrodes 2051.

[0059] Then, step S105 is performed to form a second humidity-sensitive material layer covering the first humidity-sensitive material layer and the interdigital electrodes.

[0060] In one example, if Fig.2IAs shown, a second humidity-sensitive material layer 207 covering the first humidity-sensitive material layer 202 and the interdigital electrodes 2051 is formed. By way of example, the second humidity-sensitive material layer 207 may be made of a known organic polymer humidity-sensitive material, such as polyimide, polymethyl methacrylate and its derivatives, copolymers with other monomers, etc. By way of example, the second humidity-sensitive material layer 207 is made of the same material as the first humidity-sensitive material layer 202. In this embodiment, the first humidity-sensitive material layer 202 and the second humidity-sensitive material layer 207 are made of polyimide.

[0061] Exemplarily, the method for forming the second moisture-sensitive material layer 207 includes coating and curing, wherein the coating may include spin coating and spray coating. Specifically, a polyimide precursor (i.e., a polyamic acid material) is spin-coated on the surface of the first moisture-sensitive material layer 202 and the interdigital electrode 2051, and then placed in an oven for baking imidization (i.e., curing) to form a second moisture-sensitive material layer 207 of a desired thickness. Exemplarily, the thickness of the formed second moisture-sensitive material layer 207 may be 1um-2um, such as 1um, 1.2um, 1.5um, or 2um, etc.

[0062] Next, step S106 is performed to form an opening that at least penetrates the first moisture-sensitive material layer and the second moisture-sensitive material layer to expose the sacrificial layer.

[0063] In one example, if Figure 2J As shown, an opening 208 is formed that at least penetrates the first moisture-sensitive material layer 202 and the second moisture-sensitive material layer 207. Specifically, the first moisture-sensitive material layer 202 and the second moisture-sensitive material layer 207 may be etched by a conventional etching process such as, but not limited to, exposure, dry etching, reactive ion etching (RIE), ion beam etching, plasma etching, etc., to form an opening 208 that penetrates the first moisture-sensitive material layer 202 and the second moisture-sensitive material layer 207. Exemplarily, the formed opening 208 exposes a portion of the surface of the sacrificial layer 201. As shown in FIG. Figure 3 As shown, by adjusting the interdigital electrodes 2051 to have non-equidistant spacing, the opening 208 is formed, and the sacrificial layer 201 below is removed through the opening 208, so that the moisture-sensitive material is fully in contact with the air, shortening the sensing time of the device and reducing the hysteresis.

[0064] In another example, Figure 2K As shown, the formed opening 208 also penetrates the sacrificial layer 201 to expose a portion of the surface of the substrate 200 , which is not specifically limited.

[0065] Finally, step S107 is performed to remove a portion of the sacrificial layer between the interdigital electrodes and the substrate by opening etching.

[0066] In one example, if Figure 2LAs shown, a portion of the sacrificial layer 201 between the interdigital electrodes 2051 and the substrate 200 is etched away through the opening 208. By way of example, when the formed opening 208 penetrates the first moisture-sensitive material layer 202 and the second moisture-sensitive material layer 207 and exposes a portion of the surface of the sacrificial layer 201, a dry etching process may be used but is not limited to be used to etch away a portion of the sacrificial layer 201 between the interdigital electrodes 2051 and the substrate 200, so that the first moisture-sensitive material layer 202 and the second moisture-sensitive material layer 207 wrapping the interdigital electrodes 2051 are in full contact with the air (that is, both the upper and lower surfaces of the moisture-sensitive material wrapping the interdigital electrodes 2051 are in contact with the air), thereby shortening the sensing time of the device to humidity, improving the sensitivity of the device, and achieving the purpose of full contact between the back surface and the air without the back cavity process, thereby improving the stability of the device structure.

[0067] In another example, when the formed opening 208 penetrates the first moisture-sensitive material layer 202, the second moisture-sensitive material layer 207 and the sacrificial layer 201 and exposes a portion of the surface of the substrate 200, conventional etching processes such as but not limited to dry etching, reactive ion etching (RIE), ion beam etching, plasma etching, etc. can be used to remove a portion of the sacrificial layer 201 between the interdigital electrode 2051 and the substrate 200, so that the first moisture-sensitive material layer 202 and the second moisture-sensitive material layer 207 wrapping the interdigital electrode 2051 are in full contact with the air, thereby improving the sensitivity of the device.

[0068] It is worth mentioning that the above steps are only examples, and the order of the above steps can be adjusted without conflict.

[0069] At this point, the process steps of the semiconductor device manufacturing method implemented according to an embodiment of the present application have been completed. It can be understood that the semiconductor device manufacturing method of this embodiment not only includes the above steps, but may also include other necessary steps before, during or after the above steps, which are all included in the scope of the manufacturing method of this embodiment.

[0070] In summary, the manufacturing method of the semiconductor device provided by the present application takes advantage of the metal hole filling by adjusting the process flow and process method, realizes the narrow and deep moisture-sensitive material between the interdigital electrodes, improves the capacitance density and relative capacitance area, and achieves the purpose of increasing the capacitance change of the device under the unit humidity change and improving the sensitivity of the device. The interdigital structure is adjusted to a non-equidistant structure, and the oxide sacrificial layer below is removed through the vacancies on both sides and in the middle of the interdigital fingers, forming a structure in which the entire interdigital metal is wrapped by the moisture-sensitive material in four directions, and the upper and lower surfaces of the moisture-sensitive material are fully in contact with the air. Thereby shortening the sensing time of the device to humidity, improving the sensitivity, and achieving the purpose of full contact between the back and the air without the back cavity process, thereby improving the stability of the device mechanism.

[0071] Embodiment 2

[0072] The present application also provides a semiconductor device, which can be prepared by the method in the aforementioned embodiment 1.

[0073] Below, reference Figures 2A to 2L The semiconductor device in the embodiment of the present application is introduced and described in detail. It is worth mentioning that in order to avoid repetition, only a brief description is given for the components and structures that are the same as in the aforementioned embodiment one. For specific explanations and descriptions, please refer to the description in embodiment one.

[0074] Specifically, Figures 2A to 2L As shown, the semiconductor device of the embodiment of the present application includes: a substrate 200, on which a sacrificial layer 201 is formed; a first moisture-sensitive material layer 202 is formed on the sacrificial layer 201, and a forked groove structure 203 is formed in the first moisture-sensitive material layer 202; forked electrodes 2051, located in the forked groove structure 203, and a first protective layer 204 and a second protective layer 206 are formed on the surface of the forked electrodes 2051; a first moisture-sensitive material layer 207, which covers the first moisture-sensitive material layer 202 and the forked electrodes 2051; and an opening 208 that at least penetrates the first moisture-sensitive material layer 202 and the second moisture-sensitive material layer 207.

[0075] This completes the introduction to the structure of the semiconductor device of the present application. The complete device may also include other component structures, which will not be described in detail here.

[0076] The semiconductor device of the present application forms an interdigitated groove structure in a first moisture-sensitive material layer, forms an interdigitated electrode in the interdigitated groove structure, forms a second moisture-sensitive material layer covering the interdigitated electrode, and finally forms an opening that at least penetrates the first moisture-sensitive material layer and the second moisture-sensitive material layer. The sacrificial layer between the interdigitated electrode and the substrate is removed through the opening, so that the moisture-sensitive material is fully exposed to the air, thereby shortening the sensing time of the device, reducing hysteresis, and improving the sensitivity of the device.

[0077] The present invention has been described by the above embodiments, but it should be understood that the above embodiments are only for the purpose of example and description, and are not intended to limit the present invention to the scope of the described embodiments. In addition, it can be understood by those skilled in the art that the present invention is not limited to the above embodiments, and more variations and modifications can be made according to the teachings of the present invention, and these variations and modifications all fall within the scope of the protection claimed by the present invention. The protection scope of the present invention is defined by the attached claims and their equivalents.

Claims

1. A method for manufacturing a semiconductor device, characterized in that: include: providing a substrate, and forming a sacrificial layer on the substrate; forming a first moisture-sensitive material layer on the sacrificial layer; patterning the first moisture-sensitive material layer to form an interdigitated groove structure in the first moisture-sensitive material layer; Filling electrode material in the interdigitated groove structure to form interdigitated electrodes; forming a second humidity-sensitive material layer covering the first humidity-sensitive material layer and the interdigital electrodes; forming an opening at least penetrating the first moisture-sensitive material layer and the second moisture-sensitive material layer to expose the sacrificial layer; A portion of the sacrificial layer between the interdigital electrodes and the substrate is removed by etching through the opening.

2. The manufacturing method according to claim 1, characterized in that Before filling the electrode material in the interdigitated groove structure to form the interdigitated electrodes, the method further includes: forming a first protective layer covering the first moisture-sensitive material layer, the bottom and the sidewalls of the interdigitated groove structure.

3. The manufacturing method according to claim 2, characterized in that: The step of filling the interdigitated groove structure with an electrode material to form an interdigitated electrode comprises: forming an electrode material covering the first protective layer and filling the interdigitated groove structure; A chemical mechanical polishing process is performed to stop at the surface of the first protection layer.

4. The manufacturing method according to claim 3, characterized in that: After forming the interdigital electrodes and before forming the second humidity sensitive material layer, the method further includes: forming a second protective layer covering the first protective layer and the interdigital electrodes; The first protective layer and the second protective layer located above the first moisture-sensitive material layer are removed by etching, and the remaining first protective layer and the second protective layer cover the surface of the interdigital electrode.

5. The manufacturing method according to claim 1, characterized in that: The method of forming the first moisture-sensitive material layer and the second moisture-sensitive material layer includes coating and curing.

6. The manufacturing method according to claim 5, characterized in that: The first moisture-sensitive material layer and the second moisture-sensitive material layer are made of the same material.

7. The manufacturing method according to claim 1, characterized in that: The electrode material includes at least one of the following: aluminum, copper or tungsten.

8. The manufacturing method according to claim 1, characterized in that: The opening exposes a portion of the surface of the sacrificial layer or a portion of the surface of the substrate. 9 . The manufacturing method according to claim 1 , wherein the sacrificial layer comprises an oxide layer.

10. A semiconductor device, characterized in that: The semiconductor device is manufactured by the method according to any one of claims 1 to 9.

Images