Oblique field plate structure, manufacturing method thereof and semiconductor device
By forming inclined grooves on the first imprinted layer using an imprinting mold and depositing the field plate layer, the problems of complex manufacturing process and insufficient precision of inclined field plate structure are solved, and higher manufacturing precision is achieved.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-09-09
- Publication Date
- 2026-03-10
AI Technical Summary
The manufacturing process of the inclined plate structure in the prior art is complex and it is difficult to accurately control the dimensional parameters, especially the tilt angle of the inclined plate, the distance and height between the plate and the peak electric field.
An imprinting mold is used to form an inclined groove on the first imprint layer. A deposition field layer is then formed and part of the imprint layer is removed, replacing the traditional photolithography and etching steps. The physical deformation of the imprinting mold is used to achieve pattern transfer, thereby improving manufacturing accuracy.
It breaks through the resolution limit of traditional photolithography processes, enabling more precise control over the tilt angle, plate height, and peak electric field distance of the inclined plate structure, thereby improving manufacturing accuracy.
Smart Images
Figure CN121645965A_ABST
Abstract
Description
Technical Field
[0001] This disclosure relates to the field of field plate manufacturing technology, specifically to an inclined field plate structure, its manufacturing method, and a semiconductor device. Background Technology
[0002] To reduce the electric field intensity at the gate, a field plate structure is typically placed on the side of the gate to reduce the original spike electric field. In related technologies, the field plate structure is formed through multiple deposition and etching processes, which is relatively complex. In particular, when the field plate structure is a sloping field plate, it is difficult to guarantee the dimensional accuracy of the field plate structure. Summary of the Invention
[0003] The purpose of this disclosure is to provide a sloping plate structure, a method for manufacturing the same, and a semiconductor device. The sloping plate structure and the method for manufacturing the same are to create the sloping portion of the sloping plate in the first imprint layer using an imprinting mold, which replaces the traditional photolithography and etching steps and can break through the resolution limit of traditional photolithography processes, thereby improving manufacturing precision.
[0004] To achieve the above objectives, according to a first aspect of this disclosure, a method for manufacturing an inclined plate structure is provided, comprising: A substrate is provided, and a gate structure is formed on the substrate; A first imprint layer is deposited over the substrate and the gate structure; An inclined groove is formed in the first imprinted layer on the side of the gate structure by an imprinting mold; A field plate layer is deposited on the surface of the first imprinted layer and within the inclined groove; The field plate layer and the first imprinted layer located above a portion of the gate structure are removed to form a sloping field plate structure.
[0005] Optionally, forming an inclined groove in the first imprinted layer lateral to the gate structure using an imprinting die includes: An embossing mold is provided, wherein the embossing mold includes a base portion and a protrusion portion; The embossing mold is placed above the first embossing layer, wherein the protrusion is located laterally to the gate structure; By applying pressure to the embossing mold, the protrusions form the inclined groove.
[0006] Optionally, removing the field plate layer and the first imprint layer located above a portion of the gate structure to form a sloping field plate structure includes: The field plate layers are graphically represented to define the extent of the inclined field plate structure; The field plate layer is etched to form the inclined field plate structure.
[0007] Optionally, the field plate layer material is silicon nitride.
[0008] Optionally, forming a gate structure on the substrate includes: A first oxide layer is formed on the substrate; A gate is formed by depositing polysilicon in the first oxide layer; A sidewall structure is formed on the side of the gate.
[0009] Optionally, forming a sidewall structure lateral to the gate includes: A second oxide layer, a first nitride layer, and a third oxide layer are sequentially formed above the gate. The sidewall structure is formed by etching the second oxide layer, the first nitride layer, and the third oxide layer.
[0010] Optionally, after providing the substrate and forming the gate structure on the substrate, the method further includes: A second nitride layer is deposited over the substrate and the gate structure.
[0011] Optionally, the ramp plate structure is located on the side of the gate structure facing the drain.
[0012] According to a second aspect of this disclosure, a ramp plate structure is provided, the ramp plate structure being manufactured using the manufacturing method of any one of the ramp plate structures described above.
[0013] According to a third aspect of this disclosure, a semiconductor device is also provided, the semiconductor device including the above-described inclined plate structure.
[0014] Through the above technical solution, the method for manufacturing the inclined field plate structure disclosed herein involves depositing a first imprint layer on a substrate with a gate structure, forming an inclined groove in the first imprint layer using an imprint mold, then depositing a field plate layer, and finally removing a portion of the field plate layer to form the inclined field plate. Compared with related technologies, the field plate structure disclosed herein uses an imprint mold to create the inclined portion of the inclined field plate in the first imprint layer, for example, through nanoimprinting, and then deposits the field plate layer, replacing the traditional photolithography and etching steps. The method for manufacturing the inclined field plate structure disclosed herein achieves pattern transfer by transferring the physical deformation of the first imprint layer through an imprint mold rather than changing its chemical properties. Its resolution depends on the dimensional accuracy of the imprint mold, and the imprinting process is not limited by factors such as light wavelength, objective lens value, and aperture, thus breaking through the resolution limit of traditional photolithography processes and improving manufacturing accuracy.
[0015] Other features and advantages of this disclosure will be described in detail in the following detailed description section. Attached Figure Description
[0016] The accompanying drawings are provided to further illustrate the present disclosure and form part of the specification. They are used together with the following detailed description to explain the present disclosure, but do not constitute a limitation thereof. In the drawings: Figure 1 This is a flowchart of a method for manufacturing a sloping plate structure provided in some embodiments of this disclosure.
[0017] Figures 2 to 9 These are schematic diagrams showing the steps of the manufacturing method of the inclined plate structure provided in some embodiments of this disclosure.
[0018] Explanation of reference numerals in the attached figures 100 - Substrate; 110 - First oxide layer; 200 - Gate structure; 210 - Gate; 220 - Sidewall structure; 221 - Second oxide layer; 222 - First nitride layer; 223 - Third oxide layer; 240 - Fourth oxide layer; 250 - Second nitride layer; 300 - First imprint layer; 310 - Inclined groove; 400 - Field plate layer; 410 - Inclined field plate structure; 411 - First field plate segment; 412 - Inclined segment; 413 - Second field plate segment; 500 - Imprint mold; 510 - Substrate portion; 520 - Protrusion portion. Detailed Implementation
[0019] The specific embodiments of this disclosure will be described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are for illustration and explanation only and are not intended to limit this disclosure.
[0020] In this disclosure, unless otherwise stated, directional terms such as "upper," "lower," "left," and "right" generally refer to upper, lower, left, and right relative to the figures; "far" and "near" refer to the corresponding structure or component being farther from or closer to another structure or component. Furthermore, the terms "first," "second," etc., used in this disclosure are for distinguishing one element from another and do not have sequential or importance implications. Additionally, in the following description, when referring to the figures, unless otherwise explained, the same reference numerals in different figures denote the same or similar elements. The above definitions are for explanation and illustration only and should not be construed as limiting this disclosure.
[0021] To reduce the electric field intensity at the gate, a field plate structure (including stepped field plates and inclined field plates) is typically placed on the side of the gate to reduce the original spike electric field. In related technologies, the field plate structure is formed through multiple deposition and etching processes, which are relatively complex. When the field plate structure is an inclined field plate, it is difficult to guarantee the dimensional accuracy of the field plate structure. For example, during the fabrication of the inclined field plate, dimensional parameters such as the distance between the field plate and the spike electric field, the tilt angle of the inclined field plate, and the height of the field plate cannot be precisely controlled.
[0022] The purpose of this disclosure is to provide a sloping plate structure, a method for manufacturing the same, and a semiconductor device. The sloping plate structure and the method for manufacturing the same are to create the sloping portion of the sloping plate in the first imprint layer using an imprinting mold, which replaces the traditional photolithography and etching steps and can break through the resolution limit of traditional photolithography processes, thereby improving manufacturing precision.
[0023] To achieve the above objectives, such as Figure 1 As shown, according to a first aspect of this disclosure, a method for manufacturing an inclined plate structure is provided, the method comprising steps S100 to S500.
[0024] In step S100, a substrate is provided, and a gate structure is formed on the substrate.
[0025] In step S200, a first imprint layer is deposited over the substrate and the gate structure.
[0026] In step S300, an inclined groove is formed on the first imprinted layer on the side of the gate structure by means of an imprinting mold.
[0027] In step S400, a field plate layer is deposited on the surface of the first imprinted layer and within the inclined groove.
[0028] In step S500, the field plate layer and the first imprint layer located above the partial gate structure are removed to form a sloping field plate structure.
[0029] First, a substrate 100 is provided. The substrate 100 can be a silicon substrate, a silicon-germanium substrate, a silicon carbide substrate, or a silicon-coated insulating substrate, but is not limited thereto. Then, a gate structure 200 is fabricated on the substrate 100. The gate structure 200 and its fabrication method can be found in related technologies and will not be elaborated here. After fabricating the gate structure 200, a first imprint layer 300 is deposited on top of the substrate 100 and the gate structure 200. The first imprint layer 300 is a malleable material, for example, it can be a photoresist material, a near-photoresist material, or a nanoimprintable material. After the first imprint layer 300 is deposited, an inclined groove 310 is fabricated in the first imprint layer 300 using a nanoimprint mold 500.
[0030] Through the above technical solution, the method for manufacturing the inclined field plate structure disclosed herein involves depositing a first imprint layer 300 on a substrate 100 having a gate structure 200, forming an inclined groove 310 in the first imprint layer 300 using an imprint mold 500, then depositing a field plate layer 400, and finally removing a portion of the field plate layer 400 to form the inclined field plate. Compared with related technologies, the field plate structure disclosed herein uses an imprint mold 500 to create the inclined portion of the inclined field plate in the first imprint layer 300, for example, through nanoimprinting, and then deposits the field plate layer 400, replacing the traditional photolithography and etching steps. The method for manufacturing the inclined field plate structure disclosed herein achieves pattern transfer by transferring the physical deformation of the first imprint layer 300 through the imprint mold 500 rather than changing its chemical properties. Its resolution depends on the dimensional accuracy of the imprint mold 500. The imprinting process is not limited by factors such as light wavelength, objective lens value, and aperture, and can break through the resolution limit of traditional photolithography processes, thereby improving manufacturing accuracy.
[0031] It should be noted that the aforementioned inclined groove 310 refers to a groove in which at least one sidewall is inclined, that is, the sidewall closer to the gate 210 in the groove is inclined, for forming an inclined field plate in subsequent steps. It can be understood that both sidewalls of the aforementioned inclined groove 310 can be inclined, which facilitates the setting of the corresponding protrusion 520 of the imprinting mold 500.
[0032] In some embodiments, step S300, namely forming an inclined groove 310 in the first imprinted layer 300 lateral to the gate structure 200 by means of an imprinting mold 500, includes: An embossing mold 500 is provided, wherein the embossing mold 500 includes a base portion 510 and a protrusion portion 520; The embossing mold 500 is placed above the first embossing layer 300, wherein the protrusion 520 is located laterally to the gate structure 200; By applying pressure to the embossing mold 500, the inclined groove 310 is formed by the protrusion 520.
[0033] Among them, such as Figure 6 As shown, the embossing mold 500 may include a base portion 510 and a protrusion portion 520. The base portion 510 may adopt any suitable shape to facilitate connection with other equipment (such as pressure equipment) and to apply pressure. The shape of the protrusion portion 520 corresponds to the inclined groove 310. That is, the specific shape of the protrusion portion 520 can be designed according to the size of the inclined groove 310.
[0034] like Figure 9As shown, the inclined field plate may include a first field plate segment 411, an inclined segment 412, and a second field plate segment 413. The first field plate segment 411 is formed by a field plate layer 400 deposited on the bottom of the inclined groove 310, the inclined segment 412 is formed by a field plate layer 400 deposited on the sidewall of the inclined groove 310, and the second field plate segment 413 is formed by a field plate layer 400 deposited on the first imprinted layer 300. Three parameters in the inclined plate structure are important and affect the effect of the inclined field plate: the inclination angle B of the inclined segment 412, i.e., the angle between the inclined segment 412 and the plane of the substrate 100; the height C of the second field plate segment 413, i.e., the distance between the second field plate segment 413 and the second nitride layer 250; and the distance A between the junction of the second field plate segment 413 and the inclined segment 412 and the peak electric field. To better control the three parameters mentioned above, the main parameters of the embossing mold 500 include the tilt angle of the side of the protrusion 520 and the height of the protrusion 520. Among them, the tilt angle determines the tilt angle B of the inclined plate structure 410 and the distance A between the junction of the second plate segment 413 and the inclined segment 412 and the peak electric field. The height of the protrusion 520 also controls the height C of the second plate segment 413 to a certain extent.
[0035] In some alternative embodiments, removing the field plate layer 400 and the first imprint layer 300 located above a portion of the gate structure 200 to form a sloping field plate structure 410 includes: The field plate layer 400 is graphically represented to define the extent of the inclined field plate structure 410; The field plate layer 400 is etched to form the inclined field plate structure 410.
[0036] Specifically, the patterned field plate layer 400 defines the range of the inclined field plate structure 410. This includes depositing photoresist on the field plate layer 400, patterning the photoresist, defining the range of the inclined field plate structure 410 by development, and then etching to form the inclined field plate structure 410. The specific etching method can be wet etching or dry etching, depending on the actual needs.
[0037] Optionally, the field plate layer 400 can be made of silicon nitride. Of course, the field plate layer 400 can also be made of other materials that meet the requirements, and no specific limitation is made here.
[0038] In some alternative embodiments, the step of forming the gate structure 200 on the substrate 100 includes: A first oxide layer 110 is formed on the substrate 100; A gate 210 is formed by depositing polysilicon in the first oxide layer 110; A sidewall structure 220 is formed laterally on the gate 210.
[0039] The first oxide layer 110 can be formed by deposition or infiltration, and the first oxide layer 110 can be silicon dioxide. A polysilicon layer is deposited on the first oxide layer 110, and the gate 210 is formed by photolithography and etching. After forming the gate 210, a sidewall structure 220, i.e., a sidewall, can also be formed on the sidewall of the gate 210.
[0040] In some alternative embodiments, the step of forming the sidewall structure 220 laterally on the gate 210 may include: A second oxide layer 221, a first nitride layer 222, and a third oxide layer 223 are sequentially formed above the gate 210; The sidewall structure 220 is formed by etching the second oxide layer 221, the first nitride layer 222 and the third oxide layer 223.
[0041] Specifically, a second oxide layer 221, a first nitride layer 222, and a third oxide layer 223 are sequentially formed above the gate 210 and above the first oxide layer 110 by deposition. Then, the portions above the first oxide layer 110 and above the gate 210 are removed by photolithography and etching to protect the lateral structure of the gate 210, forming a sidewall structure 220 including the second oxide layer 221, the first nitride layer 222, and the third oxide layer 223. It should be noted that the second oxide layer 221 and the third oxide layer 223 can both be made of silicon dioxide, and the first nitride layer 222 can be made of silicon nitride.
[0042] In some embodiments, after the step of providing the substrate 100 and forming the gate structure 200 on the substrate 100, the method further includes: A second nitride layer 250 is deposited over the substrate 100 and the gate structure 200.
[0043] It should be noted that a first oxide layer 110 needs to be formed on the substrate 100 before fabricating the gate structure 200. Therefore, the second oxide layer 221 can be located above the first oxide layer 110 and the gate structure 200. The second nitride layer 250 includes, but is not limited to, silicon nitride.
[0044] It is understood that the ramp structure 410 is located on one side of the gate 210 above the substrate 100, and in some embodiments, the ramp structure 410 is located on the side of the gate structure 200 facing the drain.
[0045] The manufacturing method of the inclined plate structure is described in detail below with a specific embodiment.
[0046] like Figure 2As shown, a substrate 100 is provided, and a first oxide layer 110 is formed on the substrate 100. A gate structure 200 is formed on the first oxide layer 110. The gate structure 200 includes a gate 210 and a sidewall structure 220. The sidewall structure 220 includes a second oxide layer 221, a first nitride layer 222, and a second oxide layer 221 arranged sequentially away from the gate 210.
[0047] like Figure 3 As shown, a fourth oxide layer 240 is deposited on the upper surface of the substrate 100 and the surface of the gate structure 200.
[0048] like Figure 4 As shown, a second nitride layer 250 is deposited on the surface of the fourth oxide layer 240, wherein the second nitride layer 250 includes, but is not limited to, silicon nitride.
[0049] like Figure 5 As shown, a first imprinted layer 300 (a nanoimprintable material) is deposited on the surface of the second nitride layer 250.
[0050] like Figure 6 As shown, an embossing mold 500 is provided and placed above the first embossing layer 300. The embossing mold 500 includes a base portion 510 and a protrusion portion 520.
[0051] like Figure 7 As shown, by applying a load to the embossing mold 500, an inclined groove 310 is formed, and the embossing mold 500 is removed.
[0052] like Figure 8 As shown, a field plate layer 400, for example, silicon nitride, is deposited in the first imprinted layer 300 and the inclined groove 310.
[0053] like Figure 9 As shown, the inclined field plate structure 410 is formed by photolithography and etching of the field plate layer 400 and the first imprint layer 300.
[0054] According to a second aspect of this disclosure, a sloping field plate structure 410 is provided, which is manufactured using the manufacturing method of the sloping field plate structure described in any one of the above claims. Therefore, compared with the field plate structure manufactured by conventional processes, the sloping field plate structure 410 can better control the tilt angle, the height of the field plate, and the distance between the field plate and the peak electric field, and can better weaken the electric field on the surface of the drift region.
[0055] According to a third aspect of this disclosure, a semiconductor device is also provided, which includes the aforementioned inclined plate structure 410. This semiconductor device also possesses all the advantages of the aforementioned inclined plate structure 410, which will not be repeated here. It should be noted that this semiconductor device can be a CPU chip, a GPU chip, or any chip with integrated circuits, etc.
[0056] The present disclosure discloses a method for manufacturing a sloping field plate structure, a sloping field plate structure manufactured by the method, and a semiconductor device including the sloping field plate structure. This method involves depositing a first imprint layer 300 on a substrate 100 having a gate structure 200, forming a sloping groove 310 in the first imprint layer 300 using an imprint mold 500, then depositing a field plate layer 400, and finally removing a portion of the field plate layer 400 to form the sloping field plate. Compared to related technologies, the field plate structure of this disclosure uses an imprint mold 500 to create the sloping portion of the sloping field plate in the first imprint layer 300, for example, through nanoimprinting, and then depositing the field plate layer 400. This replaces the traditional photolithography and etching steps. The method for manufacturing the sloping field plate structure of this disclosure achieves pattern transfer by transferring the physical deformation of the first imprint layer 300 through the imprint mold 500 rather than changing its chemical properties. Its resolution depends on the dimensional accuracy of the imprint mold 500. The imprinting process is not limited by factors such as light wavelength, objective lens value, or aperture, and can break through the resolution limits of traditional photolithography processes, thereby improving manufacturing accuracy.
[0057] The preferred embodiments of the present disclosure have been described in detail above with reference to the accompanying drawings. However, the present disclosure is not limited to the specific details of the above embodiments. Within the scope of the technical concept of the present disclosure, various simple modifications can be made to the technical solutions of the present disclosure, and these simple modifications all fall within the protection scope of the present disclosure.
[0058] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. In order to avoid unnecessary repetition, this disclosure will not describe the various possible combinations separately.
[0059] Furthermore, various different embodiments of this disclosure can be combined in any way, as long as they do not violate the spirit of this disclosure, they should also be regarded as the content disclosed in this disclosure.
Claims
1. A method of manufacturing a structure of a field plate, characterized by, The method comprises: providing a substrate and forming a gate structure on the substrate; depositing a first imprint layer above the substrate and the gate structure; forming an inclined groove in the first imprint layer laterally to the gate structure by an imprint mold; depositing a field plate layer on the surface of the first imprint layer and in the inclined groove; removing the field plate layer and the first imprint layer above part of the gate structure to form an inclined field plate structure.
2. The method of manufacturing a saddle field plate structure according to claim 1, wherein The method of forming an inclined groove in the first imprint layer laterally to the gate structure by an imprint mold comprises: providing an imprint mold, wherein the imprint mold comprises a base part and a protruding part; placing the imprint mold above the first imprint layer, wherein the protruding part is laterally to the gate structure; forming the inclined groove by the protruding part by applying pressure to the imprint mold.
3. The method of manufacturing a field tilt plate structure according to claim 1, wherein The method of removing the field plate layer and the first imprint layer above part of the gate structure to form an inclined field plate structure comprises: patterning the field plate layer to define the range of the inclined field plate structure; etching the field plate layer to form the inclined field plate structure.
4. The method of manufacturing a saddle field plate structure according to claim 1, wherein The field plate layer material is silicon nitride.
5. The method of manufacturing a field tilt plate structure according to claim 1, wherein The method of forming a gate structure on the substrate comprises: forming a first oxide layer on the substrate; depositing polysilicon on the first oxide layer to form a gate; forming a sidewall structure laterally to the gate.
6. The method of manufacturing a field tilt plate structure according to claim 5, wherein The method of forming a sidewall structure laterally to the gate comprises: forming a second oxide layer, a first nitride layer and a third oxide layer in sequence above the gate; forming the sidewall structure by etching the second oxide layer, the first nitride layer and the third oxide layer.
7. The method of manufacturing a field tilt plate structure according to claim 1, wherein After the method of providing a substrate and forming a gate structure on the substrate, the method further comprises: depositing a second nitride layer above the substrate and the gate structure.
8. The method of manufacturing a field tilt plate structure according to claim 1, wherein The inclined field plate structure is on the side of the gate structure facing the drain.
9. A structure of a field plate, characterized by comprising: The inclined field plate structure is made by the method of manufacturing an inclined field plate structure according to any one of claims 1-8.
10. A semiconductor device, characterized by comprising: The semiconductor device comprises the inclined field plate structure according to claim 9.