Anti-fuse switch

Abstract

The present application provides an anti-fuse switch, which includes: a first heating layer, a fusible connection layer, and a second heating layer. The first heating layer is used to connect to the first electrode of an external heating circuit. The fusible connection layer includes a fuse and a connector. The first surface of the fuse is connected to the first heating layer, and the first surface of the fuse is opposite to the second surface. The third surface of at least one connector is isolated from the third surface of the fuse by a dielectric layer of a preset thickness. The connector is used to connect the first end point of an editable element. The first surface of the second heating layer is connected to the second surface of the fuse. The second heating layer is used to connect to the second electrode of the external heating circuit and the second end point of the editable element, respectively. The heating coefficient of the first heating layer is greater than the heating coefficient of the second heating layer. After the external heating circuit is energized, the fuse melts and breaks through the dielectric layer, forming a connection with the third surface of the connector to short-circuit the editable element.

Description

Technical Field

[0001] The present application relates to the field of semiconductor technology, and in particular to an anti-fuse switch. Background Art

[0002] Currently, chip trimming during development is often performed using an antifuse switch. This involves applying an additional voltage or stress to the antifuse switch's original conduction or cutoff region, causing it to fuse or connect. Currently, polysilicon interface fuses, with their low cost and footprint, are the most commonly used trimming devices. However, the polysilicon fuses in these antifuse switches can easily generate upward and downward stress when they blow, potentially damaging associated circuit structures. This can lead to poor chip trimming results and even render the chip useless. Summary of the Invention

[0003] The present application provides an anti-fuse switch. The advantage of this anti-fuse switch is that it can be implemented without the use of an additional mask, has good stress control capabilities, can moderately guide the direction of stress generated by the anti-fuse switch when it is blown, and reduce the impact of stress in the preset direction on the chip, and has the advantage of low cost.

[0004] In a first aspect, an embodiment of the present application provides an anti-fuse switch, comprising:

[0005] a first heating layer, the first heating layer being configured to connect to a first electrode of an external heating circuit;

[0006] a fusible connection layer, the fusible connection layer comprising a fuse and a connector, wherein a first surface of the fuse is connected to the first heating layer, the first surface of the fuse is opposite to the second surface, a third surface of at least one connector is isolated from the third surface of the fuse by a dielectric layer of a preset thickness, and the connector is used to connect the first end point of the editable element;

[0007] a second heating layer, wherein a first surface of the second heating layer is connected to a second surface of the fuse, and the second heating layer is used to connect the second electrode of the external heating circuit and the second end point of the editable element, respectively. The heating coefficient of the first heating layer is greater than the heating coefficient of the second heating layer, and the heating coefficient is the sum of the heating capacity of the heating layer and the heat dissipation capacity of the connection area;

[0008] After the external heating circuit is powered on, the fuse melts and uses the thermal strain generated by the melting to break through the dielectric layer, forming a connection with the third surface of the connector to short-circuit the editable element.

[0009] In some embodiments, the connecting member comprises an open ring, and the third surfaces of the two connecting members and the third surface of the fuse are isolated from each other by the dielectric layer.

[0010] In some embodiments, the length of the first side of the fuse element ranges from: .

[0011] In some embodiments, the shape of the first surface of the fuse includes: rectangle, cross and black-mouth shape.

[0012] In some embodiments, the anti-fuse switch further comprises:

[0013] a first metal layer, the first metal layer being used to replace the first heating layer and connected to the first electrode of the external heating circuit, the first metal layer being connected to the first surface of the first heating layer;

[0014] The second metal layer is used to replace the second heating layer and is connected to the second electrode of the external heating circuit and the second end of the editable element respectively. The second metal layer is connected to the second surface of the second heating layer.

[0015] In some embodiments, an area of the first surface of the first metal layer is smaller than an area of the first surface of the second metal layer.

[0016] In some embodiments, the first heating layer and the second heating layer are made of the same material, and a contact area between the first heating layer and the fuse is smaller than a contact area between the second heating layer and the fuse.

[0017] In some embodiments, the first heating layer and the second heating layer are made of different materials, and the resistance of the first heating layer is greater than the resistance of the second heating layer.

[0018] In some embodiments, the number of the first heating layers ranges from 1 to 5, and the number of the second heating layers ranges from 2 to 10.

[0019] In some embodiments, the preset thickness of the dielectric layer ranges from 1 nm to 1000 nm.

[0020] An embodiment of the present application provides an anti-fuse switch, comprising: a first heating layer, a fusible connection layer, and a second heating layer. The first heating layer is used to connect to the first electrode of an external heating circuit. The fusible connection layer includes a fuse and a connector, the first surface of the fuse is connected to the first heating layer, the first surface of the fuse is opposite to the second surface, the third surface of at least one connector is isolated from the third surface of the fuse by a dielectric layer of a preset thickness, and the connector is used to connect the first end point of an editable element. The first surface of the second heating layer is connected to the second surface of the fuse, and the second heating layer is used to connect to the second electrode of the external heating circuit and the second end point of the editable element, respectively. The heating coefficient of the first heating layer is greater than the heating coefficient of the second heating layer. After the external heating circuit is energized, the fuse melts and breaks through the dielectric layer, forming a connection with the third surface of the connector to short-circuit the editable element. Through the above-mentioned anti-fuse switch, by setting the heating coefficient of the first heating layer to be greater than the heating coefficient of the second heating layer, when power is turned on, the charge passes from the first heating layer through the fuse to the second heating layer. Since the heat generated by the first heating layer is greater than the heat generated by the second heating layer and the carriers migrate and accumulate to the fuse and the second heating layer, the fuse is controlled to start melting from the first surface close to the first heating layer, and then the melting stress is controlled to be released toward the third surface of the fuse, thereby reducing the stress toward the first surface and the stress toward the second surface of the anti-fuse switch when melting, and also reducing the impact on the circuit structure facing the second surface of the first heating layer, thereby increasing the available space for the chip layout, and without the need to add an additional mask layer, which has the advantage of reducing costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0022] Figure 1 A schematic structural diagram of a first anti-fuse switch provided in an embodiment of the present application;

[0023] Figure 2 A schematic top view of a fusible connection layer provided in an embodiment of the present application;

[0024] Figure 3 A schematic structural diagram of a fuse provided in an embodiment of the present application;

[0025] Figure 4 A schematic structural diagram of a second anti-fuse switch provided in an embodiment of the present application;

[0026] Figure 5A schematic structural diagram of a third anti-fuse switch provided in an embodiment of the present application;

[0027] Figure 6 A schematic structural diagram of a first trimming circuit provided in an embodiment of the present application;

[0028] Figure 7 This is a structural diagram of the second trimming circuit provided in an embodiment of the present application.

[0029] Figure Number:

[0030] 400, trimming circuit; 300, external heating circuit; 200, editable component; 100, anti-fuse switch; 11, first heating layer; 12, fuse connection layer; 121, fuse; 122, connection; 13, second heating layer; 14, first metal layer; 15, second metal layer; S1, first surface; S2, second surface; S3, third surface. DETAILED DESCRIPTION

[0031] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts shall fall within the scope of protection of the present invention.

[0032] The flowcharts shown in the accompanying drawings are for illustrative purposes only and do not necessarily include all contents and operations / steps, nor must they be executed in the order described. For example, some operations / steps may be decomposed, combined, or partially merged, so the actual execution order may vary depending on the actual situation.

[0033] It should also be understood that the terms used in this specification are for the purpose of describing specific embodiments only and are not intended to limit the present application. As used in this specification and the appended claims, the singular forms "a," "an," and "the" are intended to include the plural forms unless the context clearly indicates otherwise.

[0034] It should be further understood that the term "and / or" used in this specification and the appended claims refers to and includes any and all possible combinations of one or more of the associated listed items.

[0035] See also Figure 1 , Figure 1 1 is a schematic diagram of the structure of the first anti-fuse switch provided by the embodiment of the present application. Figure 1As shown, the anti-fuse switch 100 includes: a first heating layer 11 , a fusible connection layer 12 and a second heating layer 13 . The fusible connection layer 12 includes a fuse 121 and a connection 122 .

[0036] The first heating layer 11 is used to connect to a first electrode of the external heating circuit 300 .

[0037] It should be noted that the external heating circuit 300 is used to provide heating current for the first heating layer 11 , the fusible link layer 12 , and the second heating layer 13 .

[0038] Exemplarily, the first heating layer 11 and the second heating layer 13 are both made of conductive materials, such as manganese-iron alloy or tungsten-iron alloy, and the melting points of the first heating layer 11 and the second heating layer 13 are both greater than the melting point of the fuse 121. In this way, the first heating layer 11 and the second heating layer 13 are prevented from being blown before the fuse 121 is blown.

[0039] The first surface S1 of the fuse 121 is connected to the first heating layer 11, the first surface S1 of the fuse 121 is opposite to the second surface S2, the third surface S3 of at least one connector 122 is isolated from the third surface S3 of the fuse 121 by a dielectric layer of a preset thickness, and the connector 122 is used to connect the first end point D1 of the editable element 200.

[0040] It should be noted that the editable element 200 includes a resistor and a capacitor. Figure 1 As shown, the first terminal D1 and the second terminal D2 of the editable component 200 are used to receive control signals.

[0041] In some embodiments, the preset thickness T of the dielectric layer is in the range of 1 nm to 1000 nm, so that the fuse 121 can easily break through the dielectric layer after melting, thereby improving the success rate of connecting the fuse 121 and the connector 122 .

[0042] For example, the fuse 121 is a sheet-shaped component. The planes on which the long side and wide side of the fuse 121 lie are the first surface S1 and the second surface S2, respectively. The plane on which the tall side of the fuse 121 lies is the third surface S3. It should be noted that when other layers or other components are sheet-shaped, the first surface S1, the second surface S2, and the third surface S3 are the same as those of the fuse 121 and are not further described here.

[0043] The first surface S1 of the second heating layer 13 is connected to the second surface S2 of the fuse 121. The second heating layer 13 is used to connect the second electrode of the external heating circuit 300 and the second end point of the editable element 200 respectively. The heating coefficient of the first heating layer 11 is greater than the heating coefficient of the second heating layer 13.

[0044] By setting the heating coefficient of the first heating layer 11 to be greater than the heating coefficient of the second heating layer 13, the fuse 121 is heated rapidly while the first surface S1 and the second surface S2 of the fuse 121 are heated unevenly, and the charge is transferred from the first heating layer 11 through the fuse 121 to the second heating layer 13, thereby controlling the second surface S2 of the fuse 121 to maintain its original shape when the first surface S1 of the fuse 121 begins to melt, and the carriers migrate and accumulate toward the second heating layer 13, thereby controlling the melting stress of the fuse 121 to be released toward the third surface S3 of the fuse 121, so as to prevent the circuit structure facing the second surface S2 of the fuse 121 from being destroyed.

[0045] After the external heating circuit 300 is powered on, the fuse 121 generates a melting stress and breaks through the dielectric layer, thereby forming a connection with the third surface S3 of the connector 122 to short-circuit the editable component 200 .

[0046] Exemplarily, after the external heating circuit 300 is energized, the heat required for the fuse 121 to melt mainly comes from the first heating element and the second heating element, wherein the heating coefficient of the first heating element must be greater than the heating coefficient of the second heating element. This heating coefficient is the superposition of the heating capacity of the heating layer and the heat dissipation capacity of the surrounding connection. After the fuse 121 melts, the fuse 121 is connected to the connector 122. The connector 122, the fuse 121, and the second heating layer 13 form a short-circuit channel between the first terminal D1 and the second terminal D2 of the editable element 200, thereby short-circuiting the editable element 200 and rendering the editable element 200 inoperable, thereby completing the chip adjustment.

[0047] An embodiment of the present application provides an anti-fuse switch, comprising: a first heating layer, a fusible connection layer, and a second heating layer. The first heating layer is used to connect to the first electrode of an external heating circuit. The fusible connection layer includes a fuse and a connector, the first surface of the fuse is connected to the first heating layer, the first surface of the fuse is opposite to the second surface, the third surface of at least one connector is isolated from the third surface of the fuse by a dielectric layer of a preset thickness, and the connector is used to connect the first end point of an editable element. The first surface of the second heating layer is connected to the second surface of the fuse, and the second heating layer is used to connect to the second electrode of the external heating circuit and the second end point of the editable element, respectively. The heating coefficient of the first heating layer is greater than the heating coefficient of the second heating layer. After the external heating circuit is energized, the fuse melts and breaks through the dielectric layer, forming a connection with the third surface of the connector to short-circuit the editable element. Through the above-mentioned anti-fuse switch, by setting the heating coefficient of the first heating layer to be greater than the heating coefficient of the second heating layer, when power is turned on, the heat generated by the first heating layer is greater than the heat generated by the second heating layer, thereby controlling the fuse to start melting from the first surface close to the first heating layer, and then controlling the release of the melting stress toward the third surface of the fuse, which can appropriately guide the direction of the stress generated by the anti-fuse switch when melting, reducing the stress toward the first surface and the stress toward the second surface of the anti-fuse switch when melting, and also reducing the impact on the circuit structure facing the second surface of the first heating layer, thereby increasing the available space for the chip layout, and does not require the addition of an additional mask layer, which has the advantage of reducing costs.

[0048] In order to more clearly introduce the technical solution of the present application, the technical solution of the present application will be introduced through specific embodiments below. It should be noted that the specific embodiments are used to expand the technical solution of the present application, but are not intended to limit the present application.

[0049] For example, all embodiments of the present application are implemented using a 180nm semiconductor process, where the minimum dielectric layer thickness T is 220nm and the minimum metal length of the first metal layer 14 is The following specific embodiments all use the process used in the embodiments to define the value ranges of their various parameters.

[0050] In some embodiments, see Figure 2 , Figure 2 : is a schematic top view of a fuse connection layer provided in an embodiment of the present application. Figure 2 As shown, the connecting member 122 includes an open ring shape, and the third surface S3 of the two connecting members 122 and the third surface S3 of the fuse 121 are isolated by a dielectric layer.

[0051] By changing the shape of the connecting member 122 and thereby changing the number of the third surfaces S3 of the connecting member 122 , the success rate of connecting the fuse 121 and the connecting member 122 can be increased.

[0052] In some embodiments, as Figure 2 As shown, the length L of the first side S1 of the fuse 121 ranges from: .

[0053] By setting the length of the first surface S1 of the fuse 121 , it is ensured that the fuse 121 has sufficient melt to connect with the connector 122 , thereby improving the connection stability and thus improving the chip trimming result.

[0054] In some embodiments, see Figure 3 , Figure 3 This is a schematic diagram of the structure of a fuse provided in an embodiment of the present application. Figure 3 As shown, the shapes of the first surface S1 of the fuse 121 include: rectangle, cross and black-mouth shape. It should be noted that polygons based on the above shapes are all within the protection scope of this application.

[0055] For example, different shapes have different welding effects. In addition to the above shapes, all existing shapes are within the protection scope of this application.

[0056] In some embodiments, see Figure 4 , Figure 4 : is a schematic diagram of the structure of the second anti-fuse switch provided in the embodiment of the present application. Figure 4 As shown, the anti-fuse switch 100 further includes a first metal layer 14 and a second metal layer 15. The first metal layer 14 is used to replace the first heating layer 11 and connect to the first electrode of the external heating circuit 300. The first metal layer 14 is connected to the first surface S1 of the first heating layer 11. The second metal layer 15 is used to replace the second heating layer 13 and connect to the second electrode of the external heating circuit 300 and the second terminal of the editable component 200. The second metal layer 15 is connected to the second surface S2 of the second heating layer 13.

[0057] For example, since the first heating layer 11 and the second heating layer 13 are small in size and difficult to weld, the first metal layer 14 and the second metal layer 15 are used to increase the operability of welding so as to facilitate connection with the external heating circuit 300 and the editable element 200 .

[0058] It should also be noted that the first metal layer 14 and the second metal layer 15 also have the function of maintaining structural stability to protect the corresponding circuit structure from being damaged during the fusing process.

[0059] At the same time, the first metal layer 14 and the second metal layer 15 also have the effects of heat conduction and heat dissipation.

[0060] In some embodiments, see Figure 5 , Figure 5: is a schematic diagram of the structure of the third anti-fuse switch provided by the embodiment of the present application. Figure 5 The illustrated view of the anti-fuse switch 100 is a top view from a first surface S1 perpendicular to the first metal layer 14 (the first heating layer 11 and the second heating layer 13 are not shown in the figure).

[0061] The second metal layer 15 is: The first metal layer 14 is a polygonal metal layer in the shape of a “convex” character.

[0062] It should be noted that if Figure 4 The structural diagram of the second anti-fuse switch 100 is shown as follows: Figure 5 The structural schematic diagram of the third anti-fuse switch 100 is a cross-sectional schematic diagram along line bb′.

[0063] In some embodiments, the area of the first surface S1 of the first metal layer 14 is smaller than the area of the first surface S1 of the second metal layer 15 .

[0064] By setting the area of the first surface S1 of the first metal layer 14 to be smaller than the area of the first surface S1 of the second metal layer 15, the thermal conductivity of the second metal layer 15 is better than that of the first metal layer 14, so that the heating speed of the first heating layer 11 is faster than that of the second heating layer 13.

[0065] In some embodiments, the first heating layer 11 and the second heating layer 13 are made of the same material, and the contact area between the first heating layer 11 and the fuse 121 is smaller than the contact area between the second heating layer 13 and the fuse 121 .

[0066] Through the above design, the resistance of the first heating layer 11 is greater than the resistance of the second heating layer 13 or the area of the first metal layer 14 is smaller than the area of the second metal layer 15, so that the heating coefficient of the first heating layer 11 is greater than the heating coefficient of the second heating layer 13.

[0067] In some embodiments, the first heating layer 11 and the second heating layer 13 are made of different materials, and the resistance of the first heating layer 11 is greater than the resistance of the second heating layer 13 .

[0068] Through the above design, the resistance of the first heating layer 11 is greater than the resistance of the second heating layer 13 or the area of the first metal layer 14 is smaller than the area of the second metal layer 15, so that the heating coefficient of the first heating layer 11 is greater than the heating coefficient of the second heating layer 13.

[0069] In some embodiments, the number of first heating layers 11 ranges from 1 to 5, and the number of second heating layers 13 ranges from 2 to 10.

[0070] like Figure 4As shown, the number of the first heating layer 11 is 1, and the number of the second heating layers 13 is 2.

[0071] Through the above design, the total resistance of the first heating layer 11 is in the range of 5 ohms to 10 ohms, and the total resistance of the second heating layer 13 is in the range of 4 ohms to 8 ohms. At the same time, the side length L1 of the first metal layer 14 is in the range of: , so that the side length L2 of the second metal layer 15 has a value range of , which is conducive to quickly conducting the heat on the second heating layer 13 to the second metal layer 15, so that the heating coefficient of the first heating layer 11 is greater than the heating coefficient of the second heating layer 13.

[0072] In some embodiments, the predetermined thickness of the dielectric layer ranges from 220 nm to 440 nm.

[0073] In some other embodiments, the ratio of the preset thickness of the dielectric layer to the minimum dielectric layer thickness ranges from 1 to 2.

[0074] In this way, the fuse 121 can easily break through the dielectric layer after melting, thereby improving the success rate of connecting the fuse 121 and the connector 122.

[0075] In some embodiments, see Figure 6 , Figure 6 This is a schematic diagram of the structure of the first trimming circuit provided by the embodiment of the present application. Figure 6 As shown, the trimming circuit 400 includes an anti-fuse switch 100 , an editable element 200 and an external heating circuit 300 .

[0076] Exemplarily, the external heating circuit 300 includes a preset voltage source VDD, a first switch transistor QN, and a second switch transistor QM. A first terminal of the first switch transistor QN is connected to VDD, a second terminal of the first switch transistor QN is connected to a first terminal of an anti-fuse switch 100, a second terminal of the anti-fuse switch 100 is connected to a first terminal of the second switch transistor QM, and a second terminal of the second switch transistor QM is grounded. By turning on the first and second switches QN and QM, a fusing current is supplied to the anti-fuse switch 100, which is used to short-circuit the first and second terminals D1 and D2 of the editable element 200.

[0077] In the external heating circuit 300 described above, the first switching transistor QN is a PMOS transistor, and the second switching transistor QM is an NMOS transistor. The switching transistors are controlled to provide a fusing current ranging from 90mA to 100mA, with a fusing time of 1ms to 100ms. It should be noted that in some other embodiments, the external heating circuit 300 can still fully function by retaining only one of the first switching transistor QN or the second switching transistor QM.

[0078] In some embodiments, see Figure 7 , Figure 7 : is a schematic diagram of the structure of the second trimming circuit provided in the embodiment of the present application. Figure 7 As shown, the trimming circuit 400 includes: a plurality of anti-fuse switches 100 , a plurality of programmable resistors and an external heating circuit 300 .

[0079] In the aforementioned trimming circuit 400, an N-bit signal controls the anti-fuse switches, including N groups of fuse switches (specifically, N = 8), corresponding to the first switches QN1, ..., QN7, and QN8, as well as the editable resistors R1, ..., R7, and R8, and the first switches QM1, ..., QM7, and QM8. The trimming circuit 400 performs a fuse operation on the anti-fuse switches 100 based on a selection signal (the N-bit signal).

[0080] By using the trimming circuit 400 , the required layout area can be reduced without affecting the operation.

[0081] The above are only specific embodiments of the present application, but the scope of protection of the present application is not limited thereto. Any person skilled in the art can easily conceive of various equivalent modifications or substitutions within the technical scope disclosed in this application, and such modifications or substitutions should be included in the scope of protection of this application. Therefore, the scope of protection of this application should be based on the scope of protection of the claims.

Claims

1. An anti-fuse switch, characterized in that: The anti-fuse switch comprises: a first heating layer, the first heating layer being configured to connect to a first electrode of an external heating circuit; a fusible connection layer, the fusible connection layer comprising a fuse and a connector, wherein a first surface of the fuse is connected to the first heating layer, the first surface of the fuse is opposite to the second surface, a third surface of at least one connector is isolated from the third surface of the fuse by a dielectric layer of a preset thickness, and the connector is used to connect the first end point of the editable element; a second heating layer, wherein a first surface of the second heating layer is connected to a second surface of the fuse, the second heating layer is used to connect to a second electrode of the external heating circuit and a second end point of the editable element, respectively, and a heating coefficient of the first heating layer is greater than a heating coefficient of the second heating layer; Wherein, after the external heating circuit is energized, the fuse melts and breaks through the dielectric layer, forming a connection with the third surface of the connector to short-circuit the editable element.

2. The anti-fuse switch according to claim 1, wherein: The connecting member comprises an open ring, and the third surfaces of the two connecting members and the third surface of the fuse are isolated from each other by the dielectric layer.

3. The anti-fuse switch according to claim 2, wherein: The length of the first side of the fuse is in the range of: 0.1 -10 .

4. The anti-fuse switch according to claim 1, wherein: The shapes of the first surface of the fuse include rectangle, cross and black-mouth shape. The black-mouth shape is composed of a rectangle and a triangle. The rectangle and the triangle have a common side, which is a side of the rectangle close to the connector.

5. The anti-fuse switch according to claim 1, wherein: The anti-fuse switch further includes: a first metal layer, wherein the third surface of the first metal layer is used to be connected to the first electrode of the external heating circuit, and the second surface of the first metal layer is connected to the first surface of the first heating layer; The second metal layer, the third surface of the second metal layer is used to connect to the second electrode of the external heating circuit and the second end point of the editable element respectively, and the first surface of the second metal layer is connected to the second surface of the second heating layer.

6. The anti-fuse switch according to claim 5, wherein: An area of the first surface of the first metal layer is smaller than an area of the first surface of the second metal layer.

7. The anti-fuse switch according to any one of claims 1 to 6, wherein: The first heating layer and the second heating layer are made of the same material, and a contact area between the first heating layer and the fuse is smaller than a contact area between the second heating layer and the fuse.

8. The anti-fuse switch according to any one of claims 1 to 6, wherein: The first heating layer and the second heating layer are made of different materials, and the resistance of the first heating layer is greater than the resistance of the second heating layer.

9. The anti-fuse switch according to any one of claims 1 to 6, wherein: The number of the first heating layers ranges from 1 to 5, and the number of the second heating layers ranges from 2 to 10.

10. The anti-fuse switch according to claim 1, wherein: The preset thickness of the dielectric layer ranges from 1 nm to 1000 nm.

Images