Chip thin film resistor and preparation method thereof

Abstract

The present invention discloses a chip thin-film resistor and a method for manufacturing the same. The chip thin-film resistor includes an insulating substrate, a thin-film resistor, and a surface electrode. The surface electrode and the thin-film resistor are both disposed on the insulating substrate, and the thin-film resistor is formed in the middle of the surface electrode. The thin-film resistor separates the surface electrode into a first electrode and a second electrode. The thin-film resistor includes a first connecting portion, a second connecting portion, and a third connecting portion. One end of the first connecting portion is disposed on the same side edge of the first electrode and the second electrode, one end of the third connecting portion is disposed on the same other side edge of the first electrode and the second electrode, and the second connecting portion is connected to the other end of the first connecting portion and the other end of the third connecting portion, respectively. The present invention can increase the length of the resistor and reduce the resistance value of the resistor.

Description

Technical Field

[0001] The present invention relates to the technical field of electronic production, and in particular to a chip-type thin-film resistor and a preparation method thereof. Background Art

[0002] With the miniaturization of computer technology and microelectronics technology, thin film resistors with small size and low resistance loss have become one of the important components of electronic equipment.

[0003] In the prior art, the shape of the resistor body in a thin film resistor is rectangular, and different resistance values ​​are obtained by changing the area of ​​the rectangle. However, the length of the resistor body in the existing thin film resistor is highly dependent on the length of the surface electrode, so that the existing thin film resistor can only increase the width of the resistor body to increase the area of ​​the rectangle to reduce the resistance value, resulting in the existing thin film resistor being unable to obtain a lower resistance value when the resistor width remains unchanged. Summary of the Invention

[0004] The present invention provides a chip thin film resistor and a preparation method thereof to solve the technical problem that existing chip thin film resistors cannot obtain a lower resistance value when the resistor width and the surface electrode layer length remain unchanged. The present invention can increase the length of the resistor and reduce the resistance value of the resistor.

[0005] In order to solve the above technical problems, an embodiment of the present invention provides a chip-type thin-film resistor, comprising: an insulating substrate, a thin-film resistor, and a surface electrode;

[0006] The surface electrode and the thin film resistor are both provided on the insulating substrate, and the thin film resistor is formed in the middle of the surface electrode; the thin film resistor separates the surface electrode into a first electrode and a second electrode;

[0007] The thin film resistor includes a first connecting portion, a second connecting portion, and a third connecting portion;

[0008] One end of the first connecting portion is arranged on the same side edge of the first electrode and the second electrode, one end of the third connecting portion is arranged on the other side edge of the first electrode and the second electrode, and the second connecting portion is connected to the other end of the first connecting portion and the other end of the third connecting portion respectively.

[0009] As a preferred solution, the length of the second connecting portion is greater than the line spacing between the first connecting portion and the third connecting portion.

[0010] As a preferred solution, the second connecting portion includes a first connecting section;

[0011] One end of the first connecting section is connected to the other end of the first connecting portion; the other end of the first connecting section is connected to the other end of the third connecting portion;

[0012] An angle formed between the first connecting section and the first connecting portion is less than 180°; an angle formed between the first connecting section and the third connecting portion is less than 180°.

[0013] As a preferred solution, the first connecting portion is parallel to the third connecting portion.

[0014] As a preferred solution, the second connecting portion includes a first connecting section, a second connecting section, and a third connecting section;

[0015] One end of the first connecting section is connected to the other end of the first connecting portion; the other end of the first connecting section is connected to one end of the second connecting section;

[0016] The other end of the second connecting segment is connected to one end of the third connecting segment, and the other end of the third connecting segment is connected to the other end of the third connecting portion;

[0017] The angle formed by the first connecting section and the first connecting portion is less than or equal to 90°; the angle formed by the first connecting section and the second connecting section is less than or equal to 90°;

[0018] An angle formed between the second connecting section and the third connecting section is less than or equal to 90°; an angle formed between the third connecting section and the third connecting portion is less than or equal to 90°.

[0019] As a preferred solution, the first connecting portion and the third connecting portion are arranged on the same straight line; the first connecting portion and the third connecting portion are respectively parallel to the second connecting section.

[0020] As a preferred solution, the second connecting portion includes a first connecting section, a second connecting section, and a third connecting section;

[0021] One end of the first connecting section is connected to the other end of the first connecting portion; the other end of the first connecting section is connected to one end of the second connecting section;

[0022] The other end of the second connecting segment is connected to one end of the third connecting segment, and the other end of the third connecting segment is connected to the other end of the third connecting portion;

[0023] The angle formed between the first connecting section and the first connecting portion is greater than 90°; the angle formed between the first connecting section and the second connecting section is greater than 90°;

[0024] An angle formed between the second connecting section and the third connecting section is greater than 90°; an angle formed between the third connecting section and the third connecting portion is greater than 90°.

[0025] As a preferred solution, the first connecting portion and the third connecting portion are arranged on the same straight line; the first connecting portion and the third connecting portion are respectively parallel to the second connecting section.

[0026] As a preferred solution, the first connecting portion is vertically provided on the same side edge of the first electrode and the second electrode; the third connecting portion is vertically provided on the other side edge of the first electrode and the second electrode.

[0027] Accordingly, an embodiment of the present invention further provides a method for preparing a chip-type thin-film resistor, comprising:

[0028] Providing an insulating substrate, the insulating substrate comprising a first surface and a second surface, the first surface and the second surface being arranged opposite to each other;

[0029] A first mask is provided on the first surface, and a layer of resistive film is deposited by a deposition technique and then the first mask is removed to obtain a thin film resistive layer;

[0030] A second mask is provided on the surface of the thin film resistor layer, and after depositing an electrode film layer by chemical deposition technology, the second mask is removed to obtain a surface electrode layer.

[0031] Compared with the prior art, the embodiments of the present invention have the following beneficial effects:

[0032] An embodiment of the present invention provides a chip-type thin film resistor, comprising an insulating substrate, a thin film resistor, and a surface electrode; the surface electrode and the thin film resistor are both provided on the insulating substrate, and the thin film resistor is formed in the middle of the surface electrode; the thin film resistor separates the surface electrode into a first electrode and a second electrode; the thin film resistor comprises a first connecting portion, a second connecting portion, and a third connecting portion; one end of the first connecting portion is provided on the same side edge of the first electrode and the second electrode, one end of the third connecting portion is provided on the same other side edge of the first electrode and the second electrode, and the second connecting portion is connected to the other end of the first connecting portion and the other end of the third connecting portion, respectively. By providing the second connecting portion between the first connecting portion and the third connecting portion, the width of the thin film resistor is increased, thereby increasing the cross-sectional area of ​​the resistor body, reducing the square resistance of the resistor, and thereby reducing the resistance value of the resistor. Compared with simply shortening the resistor length so that the resistor band is concentrated in the middle of the resistor, the resistor is distributed over a larger area, effectively improving the heat dissipation efficiency and significantly improving the power characteristics. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 1 is a schematic structural diagram of a chip thin film resistor in an embodiment of the present invention;

[0034] Figure 2Schematic diagram of the structure of the electrode and resistor parts in an embodiment of the present invention;

[0035] Figure 3 It is a schematic diagram of the structure of an existing thin film resistor;

[0036] Figure 4 1 is a flow chart of a method for preparing a chip-type thin-film resistor according to an embodiment of the present invention;

[0037] The reference numerals in the accompanying drawings of the specification are as follows:

[0038] 1. Insulating substrate; 2. First mask; 3. Thin film resistor; 4. Second mask; 5. Surface electrode; 6. Laser resistance line; 7. Resin protective layer; 8. Back electrode layer; 9. Nickel-chromium layer; 10. Nickel layer; 11. Tin layer. DETAILED DESCRIPTION

[0039] 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 the embodiments. 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.

[0040] First embodiment

[0041] See Figure 1 , an embodiment of the present invention provides a chip-type thin film resistor, comprising: an insulating substrate 1, a thin film resistor 3, and a surface electrode 5;

[0042] First, a thin film resistor 3 is provided on the insulating substrate 1 , and then a pair of opposite electrodes 5 are provided to cover both ends of the thin film resistor 3 .

[0043] See Figure 2 , Figure 2 The diagram shows the structure of the electrode and resistor parts in the embodiment of the present invention, which includes three different electrode patterns. In the actual processing process, a rectangular thin film resistor layer is first formed, and then a mask is set to block the Figure 2 The portion of the thin-film resistor 3 corresponding to the thin-film resistor 3 in the image is covered by a planar electrode 5. After removing the mask, the planar electrodes 5 covering both ends of the resistor and the thin-film resistor 3 exposed in the middle are obtained. Due to the different mask patterns, the planar electrodes 5 formed have different patterns, and therefore the thin-film resistor 3 not covered by the planar electrode 5 has different patterns.

[0044] The thin film resistor 3 includes a first connecting portion, a second connecting portion, and a third connecting portion;

[0045] One end of the first connecting portion is arranged on the same side edge of the first electrode and the second electrode, one end of the third connecting portion is arranged on the other side edge of the first electrode and the second electrode, and the second connecting portion is connected to the other end of the first connecting portion and the other end of the third connecting portion respectively.

[0046] In a preferred embodiment, the chip thin film resistor also includes a resin protective layer 7, a back electrode layer 8, a nickel-chromium layer 9, a nickel layer 10, and a tin layer 11; the surface electrode 5 and the thin film resistor layer 3 are covered with the resin protective layer 7, the surface electrode 5 and the thin film resistor 3 are both arranged on the first surface of the insulating substrate 1, and the back electrode layer 8 is arranged on the second surface of the insulating substrate 1. The first surface is connected to the surface electrode layer 5 through the nickel-chromium layer 9, and the second surface is connected to the back electrode layer 8. Based on electroplating technology, a nickel layer 10 and a tin layer 11 for welding with external components are provided on the surface of the nickel-chromium layer 9.

[0047] In a preferred embodiment, Figure 2 As shown, the length of the second connecting portion is greater than the line spacing between the first connecting portion and the third connecting portion; the first connecting portion is vertically arranged on the same side edge of the first electrode and the second electrode; the third connecting portion is vertically arranged on the same other side edge of the first electrode and the second electrode.

[0048] As a preferred embodiment, the second connecting portion includes a first connecting section; one end of the first connecting section is connected to the other end of the first connecting section; the other end of the first connecting section is connected to the other end of the third connecting section; the angle formed by the first connecting section and the first connecting section is less than 180°; the angle formed by the first connecting section and the third connecting section is less than 180°; the first connecting section is parallel to the third connecting section. For details, please refer to Figure 2 Middle (a).

[0049] As a preferred embodiment, the second connecting portion includes a first connecting section, a second connecting section, and a third connecting section; one end of the first connecting section is connected to the other end of the first connecting section; the other end of the first connecting section is connected to one end of the second connecting section; the other end of the second connecting section is connected to one end of the third connecting section, and the other end of the third connecting section is connected to the other end of the third connecting section; the angle formed by the first connecting section and the first connecting section is less than or equal to 90°; the angle formed by the first connecting section and the second connecting section is less than or equal to 90°; the angle formed by the second connecting section and the third connecting section is less than or equal to 90°; the angle formed by the third connecting section and the third connecting section is less than or equal to 90°; the first connecting section and the third connecting section are arranged on the same straight line; the first connecting section and the third connecting section are respectively parallel to the second connecting section. For specific details, please refer to Figure 2 Middle (b).

[0050] As a preferred embodiment, the second connecting portion includes a first connecting section, a second connecting section, and a third connecting section; one end of the first connecting section is connected to the other end of the first connecting section; the other end of the first connecting section is connected to one end of the second connecting section; the other end of the second connecting section is connected to one end of the third connecting section, and the other end of the third connecting section is connected to the other end of the third connecting section; the angle formed by the first connecting section and the first connecting section is greater than 90°; the angle formed by the first connecting section and the second connecting section is greater than 90°; the angle formed by the second connecting section and the third connecting section is greater than 90°; the angle formed by the third connecting section and the third connecting section is greater than 90°, and the first connecting section and the third connecting section are arranged on the same straight line; the first connecting section and the third connecting section are respectively parallel to the second connecting section. For specific details, please refer to Figure 2 Middle (c).

[0051] In this embodiment, the second connecting portion is provided between the first connecting portion and the third connecting portion to increase the length of the thin film resistor, thereby increasing the cross-sectional area of ​​the resistor body, thereby reducing the square resistance of the resistor and further reducing the resistance value of the resistor.

[0052] In this embodiment, it can be seen from the resistance calculation formula R=p*L / (S*h) that when the resistivity and the resistor length are constant, the only factors that affect the size of the resistor are the area of ​​the resistor and the thickness of the resistor layer. Therefore, in this embodiment, when the resistance value is the same, the thickness of the resistor layer is reduced by increasing the area of ​​the resistor, thereby saving material and reducing deposition time.

[0053] See Figure 4 , an embodiment of the present invention further provides a method for preparing a chip-type thin film resistor, comprising the following steps:

[0054] S1: providing an insulating substrate 1, wherein the insulating substrate 1 comprises a first surface and a second surface, wherein the first surface and the second surface are arranged opposite to each other;

[0055] S2: a first mask 2 is provided on the first surface, a resistive film layer is deposited by a deposition technique, and then the first mask 2 is removed to obtain a thin film resistive layer 3;

[0056] S3: a second mask 4 is provided on the surface of the thin film resistor layer 3, and an electrode film layer is deposited by chemical deposition technology, and then the second mask 4 is removed to obtain a surface electrode layer 5;

[0057] S4: forming a back electrode layer 8 on the second surface to obtain a chip-type thin-film resistor.

[0058] In a preferred embodiment, the deposition technology in step S2 is a physical deposition technology or a chemical deposition technology; wherein, the physical deposition technology mainly bombards the target material with charged ions (inert gas) in a vacuum environment, and the metal ions are bombarded out and deposited on the insulating substrate 1 through the potential difference; the chemical deposition technology mainly causes the gas phase compound or element containing the thin film element to undergo a chemical reaction on the bottom surface to form a thin film.

[0059] In a preferred embodiment, the insulating substrate 1 is an alumina ceramic substrate, the thin film resistor 3 is made of a nickel-chromium alloy material, and the surface electrode 5 is made of a copper material.

[0060] In a preferred embodiment, the chemical deposition technology in step S3 is mainly through electrochemical deposition technology, where the object to be plated is used as the cathode and copper is used as the anode, which are placed in the electroplating solution. After power is applied, an oxidation-reduction reaction is carried out to deposit a layer of copper on the plated object.

[0061] In a preferred embodiment, after step S3, the thin film resistor layer 3 is cut into trimming lines 6 by laser cutting, and the effective width of the thin film resistor layer 3 is changed by the trimming lines 6 to obtain the target resistance value.

[0062] In a preferred embodiment, the surfaces of the thin film resistor layer 3 and the surface electrode layer 5 are covered with a resin protection layer 7 .

[0063] In a preferred embodiment, the first surface is connected to the surface electrode layer 5 through the nickel-chromium layer 9 , and the second surface is connected to the back electrode layer 8 .

[0064] In a preferred embodiment, a nickel layer 10 and a tin layer 11 for soldering with external components are provided on the surface of the nickel-chromium layer 9 based on electroplating technology.

[0065] As can be seen from the above, an embodiment of the present invention provides a chip thin film resistor, comprising an insulating substrate, a thin film resistor, and a surface electrode; the surface electrode and the thin film resistor are both provided on the insulating substrate, and the thin film resistor is formed in the middle of the surface electrode; the thin film resistor separates the surface electrode into a first electrode and a second electrode; the thin film resistor comprises a first connecting portion, a second connecting portion, and a third connecting portion; one end of the first connecting portion is provided on the same side edge of the first electrode and the second electrode, one end of the third connecting portion is provided on the same other side edge of the first electrode and the second electrode, and the second connecting portion is connected to the other end of the first connecting portion and the other end of the third connecting portion respectively. By providing a second connecting portion between the first connecting portion and the third connecting portion, the length of the thin film resistor (also referred to as the width, in the calculation of resistance, the distance between the two electrodes is usually referred to as the "length" and the direction perpendicular to it is referred to as the "width") is increased, thereby increasing the cross-sectional area of ​​the resistor body, reducing the square resistance of the resistor, and thereby reducing the resistance value of the resistor. Compared with simply shortening the resistor length so that the resistor band is concentrated in the middle of the resistor, the resistor is distributed over a larger area, effectively improving the heat dissipation efficiency and significantly improving the power characteristics.

[0066] The above is a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications are also considered to be within the scope of protection of the present invention.

Claims

1. A chip thin film resistor, characterized in that: include: Insulating substrate, thin film resistor, surface electrode; The surface electrode and the thin film resistor are both provided on the insulating substrate, and the thin film resistor is formed in the middle of the surface electrode; the thin film resistor separates the surface electrode into a first electrode and a second electrode; The thin film resistor includes a first connecting portion, a second connecting portion, and a third connecting portion; One end of the first connecting portion is provided on the same side edge of the first electrode and the second electrode, one end of the third connecting portion is provided on the other side edge of the first electrode and the second electrode, and the second connecting portion is connected to the other end of the first connecting portion and the other end of the third connecting portion respectively; By adding the second connecting portion between the first connecting portion and the third connecting portion, the length of the thin film resistor is increased, thereby reducing the resistance value of the thin film resistor; The length of the second connecting portion is greater than the line spacing between the first connecting portion and the third connecting portion; The chip-type thin-film resistor further includes a resin protection layer, a back electrode layer, a nickel-chromium layer, a nickel layer, and a tin layer.

2. The chip-type thin film resistor according to claim 1, wherein The second connecting portion includes a first connecting section; One end of the first connecting section is connected to the other end of the first connecting portion; the other end of the first connecting section is connected to the other end of the third connecting portion; An angle formed between the first connecting section and the first connecting portion is less than 180°; an angle formed between the first connecting section and the third connecting portion is less than 180°.

3. The chip-type thin film resistor according to claim 2, wherein: The first connecting portion is parallel to the third connecting portion.

4. The chip-type thin film resistor according to claim 1, wherein The second connecting portion includes a first connecting section, a second connecting section, and a third connecting section; One end of the first connecting section is connected to the other end of the first connecting portion; the other end of the first connecting section is connected to one end of the second connecting section; The other end of the second connecting segment is connected to one end of the third connecting segment, and the other end of the third connecting segment is connected to the other end of the third connecting portion; The angle formed by the first connecting section and the first connecting portion is less than or equal to 90°; the angle formed by the first connecting section and the second connecting section is less than or equal to 90°; An angle formed between the second connecting section and the third connecting section is less than or equal to 90°; an angle formed between the third connecting section and the third connecting portion is less than or equal to 90°.

5. The chip-type thin film resistor according to claim 4, wherein: The first connecting portion and the third connecting portion are arranged on the same straight line; the first connecting portion and the third connecting portion are respectively parallel to the second connecting section.

6. The chip-type thin film resistor according to claim 1, wherein The second connecting portion includes a first connecting section, a second connecting section, and a third connecting section; One end of the first connecting section is connected to the other end of the first connecting portion; the other end of the first connecting section is connected to one end of the second connecting section; The other end of the second connecting segment is connected to one end of the third connecting segment, and the other end of the third connecting segment is connected to the other end of the third connecting portion; The angle formed between the first connecting section and the first connecting portion is greater than 90°; the angle formed between the first connecting section and the second connecting section is greater than 90°; An angle formed between the second connecting section and the third connecting section is greater than 90°; an angle formed between the third connecting section and the third connecting portion is greater than 90°.

7. The chip-type thin film resistor according to claim 6, wherein: The first connecting portion and the third connecting portion are arranged on the same straight line; the first connecting portion and the third connecting portion are respectively parallel to the second connecting section.

8. The chip-type thin film resistor according to any one of claims 1 to 7, characterized in that: The first connecting portion is vertically arranged on the same side edge of the first electrode and the second electrode; and the third connecting portion is vertically arranged on the other side edge of the first electrode and the second electrode.

9. A method for preparing a chip-type thin film resistor, characterized in that: include: Providing an insulating substrate, the insulating substrate comprising a first surface and a second surface, the first surface and the second surface being arranged opposite to each other; A first mask is provided on the first surface, and a layer of resistive film is deposited by a deposition technique and then the first mask is removed to obtain a thin film resistive layer; A second mask is provided on the surface of the thin film resistor layer, and an electrode film layer is deposited by chemical deposition technology and then the second mask is removed to obtain a surface electrode layer; Wherein, the thin film resistor is formed in the middle of the surface electrode layer; the thin film resistor separates the surface electrode layer into a first electrode and a second electrode; The thin film resistor includes a first connecting portion, a second connecting portion, and a third connecting portion; By adding the second connecting portion between the first connecting portion and the third connecting portion, the length of the thin film resistor is increased, thereby reducing the resistance value of the thin film resistor; The length of the second connecting portion is greater than the line spacing between the first connecting portion and the third connecting portion; The chip-type thin-film resistor further includes a resin protection layer, a back electrode layer, a nickel-chromium layer, a nickel layer, and a tin layer.

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