TWI733120B - Thin film resistor - Google Patents

Abstract

A thin film resistor is provided to solve the problem where the conventional film resistor tends to suffer from electrochemical erosion and has a low cooling efficiency. The thin film resistor includes a substrate having a mounting face, a resistor layer on the mounting face, and a metallic protection layer on a face of the resistor layer opposite to the mounting face of the substrate. The metallic protection layer forms from tantalum, hafnium, tungsten, silver, platinum, palladium, ruthenium or an alloy thereof.

Description

Thin film resistors

The present invention relates to an electronic component, especially a thin film resistor which prevents electrochemical corrosion, reduces thickness and improves heat dissipation.

In the thin film or semiconductor manufacturing process, the resistive material can be deposited on the wafer with a thickness of nanometers to form a thin film resistor with an area much larger than the thickness. Due to the low temperature coefficient of the thin film resistor, its resistance value is stable and difficult to change with temperature. Changes can be applied to precision instruments such as measuring instruments, medical equipment, and digital products.

The above-mentioned conventional thin film resistors usually use Nichrome as the resistance layer and cover the epoxy resin (Epoxy) on the resistance layer to prevent electrochemical corrosion from causing damage to the Nichrome alloy. Avoid changing the resistance value of the thin film resistor. However, epoxy resin is an organic material, and its thermal conductivity is poorer than that of metal materials, which affects the heat dissipation of thin film resistors and increases the thickness of the overall structure.

In view of this, there is indeed still a need to improve the conventional thin film resistors.

In order to solve the above problems, the purpose of the present invention is to provide a thin film resistor which can resist electrochemical corrosion.

The second objective of the present invention is to provide a thin film resistor, which can improve the heat dissipation of the element sex.

Another object of the present invention is to provide a thin film resistor, which can reduce the overall thickness of the element.

The elements and components described in the full text of the present invention use the quantifiers "one" or "one" for convenience and to provide the general meaning of the scope of the present invention; in the present invention, it should be construed as including one or at least one, and single The concept of also includes the plural, unless it clearly implies other meanings.

The thin film resistor of the present invention includes: a substrate having a bearing surface; a resistance layer located on the bearing surface; and a metal protective layer located on the other surface of the resistance layer opposite to the bearing surface, and the metal protective layer is It is composed of tantalum, hafnium, tungsten, silver, platinum, palladium, ruthenium or alloys of the above elements.

Accordingly, the thin-film resistor of the present invention uses a metal with low activity to form a resistance layer or a protective layer covering the resistance. The metal or metal oxide that is not affected by electrochemical corrosion can prevent the thin-film resistor from being corroded and changing the resistance. It has the functions of stabilizing the resistance value and improving the heat dissipation of the component.

Wherein, the resistance layer is made of nickel-chromium alloy or chromium-silicon alloy. In this way, it has the effect of increasing the melting point and strength of the resistance layer.

Wherein, the substrate has two electrode parts, the two electrode parts are respectively located at two ends of the carrying surface, and the resistance layer is electrically connected to the two electrode parts respectively. In this way, it has the effect of guiding current to act on the resistive layer.

Wherein, the thickness of the resistance layer is less than 10 microns. In this way, it has the effect of reducing the thickness of the device and improving the heat dissipation efficiency.

The thin film resistor of the present invention includes: a substrate having a bearing surface; and a resistance layer located on the bearing surface, the resistance layer is made of tantalum, hafnium, tungsten, silver, platinum, palladium, ruthenium or alloys of the above elements constitute. The system can prevent the film resistor from being corroded and change the resistance value, and has a stable resistance value, Reduce component thickness and improve component heat dissipation and other effects.

1‧‧‧Substrate

11‧‧‧Electrode

2‧‧‧Resistance layer

3‧‧‧Metal protective layer

S‧‧‧Loading surface

[Figure 1] A side cross-sectional view of the first embodiment of the present invention.

[Figure 2] A side cross-sectional view of the second embodiment of the present invention.

[Figures 3a~3d] The data correlation diagram of the electrochemical corrosion water drop test performed in the present invention.

In order to make the above and other objects, features and advantages of the present invention more comprehensible, the preferred embodiments of the present invention will be described in detail in conjunction with the accompanying drawings as follows: Please refer to Figure 1. It is the first embodiment of the thin film resistor of the present invention, which includes a substrate 1, a resistance layer 2 and a metal protection layer 3. The resistance layer 2 and the metal protection layer 3 are located on the substrate 1, and the resistance layer 2 It is covered by the metal protective layer 3 and the substrate 1 up and down.

The substrate 1 is used to carry various electronic components and circuits. Metal materials can be formed on the carrying surface S of the substrate 1 by sputtering, evaporation, laser deposition and other techniques. The substrate 1 can also have two electrode parts. 11. The two electrode parts 11 are respectively located at two ends of the bearing surface S. The substrate 1 may be a crystalline material such as silicon wafer, aluminum oxide, aluminum nitride, etc., and the two electrode portions 11 may be a metal conductor.

The resistance layer 2 is formed on the supporting surface S in a thin film with a thickness of less than 10 microns, and the resistance layer 2 is electrically connected to the two electrode portions 11 respectively. The resistance layer 2 can be a nickel-chromium alloy or a chromium-silicon alloy (Chromium-Silicon).

The metal protection layer 3 is located on the other surface of the resistance layer 2 opposite to the carrying surface S, so that the metal protection layer 3 and the substrate 1 can cover the resistance layer 2 and reduce the intrusion of solution into the electric Probability of the barrier layer 2, the metal protective layer 3 can be tantalum (Ta), hafnium (Hf), tungsten (W) and other high corrosion resistance group 4, 5, 6 metal elements, or gold (Au), Silver (Ag), platinum (Pt), palladium (Pd), ruthenium (Ru) and other precious metals with low activity, the metal protective layer 3 can be an alloy formed by a plurality of metal materials in a specific ratio, by applying the metal protective layer Metal oxide is formed on the surface of 3, which can prevent the internal resistance layer 2 from being electrochemically corroded.

Please refer to Figure 2, which is the second embodiment of the thin film resistor of the present invention. It includes a substrate 1 and a resistive layer 2. The resistive layer 2 is located on the carrying surface S of the substrate 1, and the resistive layer 2 can be It is a group 4, 5, 6 metal element with high corrosion resistance such as tantalum (Ta), hafnium (Hf), and tungsten (W). It can also be gold (Au), silver (Ag), platinum (Pt), palladium ( Pd), ruthenium (Ru) and other precious metals with low activity. The resistance layer 2 can be an alloy formed of a plurality of metal materials in a specific ratio. By forming a metal oxide on the surface of the resistance layer 2, the resistance layer 2 can be prevented 2 Electrochemical corrosion occurs. In addition, the thickness of the resistance layer 2 is less than 10 microns.

Please refer to Figures 3a~3d, which is an electrochemical corrosion water drop test with the thin film resistor of the present invention. Electrolytes of different conductivity are dropped on the thin film resistor regularly and quantitatively, and the recorded resistance value change ratio and the process Time data correlation graph, where the electrolyte with lower conductivity (4μS/cm) can be pure water, and the electrolyte with higher conductivity (400μS/cm) can be tap water. As shown in Figure 3a, the thin film resistors are formed by hafnium; as shown in Figure 3b, the thin film resistors are formed by electroplating hafnium and tantalum at 50 watts and 150 watts respectively; as shown in Figure 3c, the thin film resistors are formed by electroplating hafnium and tantalum. The resistors are formed by electroplating hafnium and tantalum with a power of 100 watts; as shown in Figure 3d, the thin film resistors are formed by electroplating hafnium and tantalum with a power of 150 watts and 50 watts, respectively.

It can be seen from Figures 3a to 3d that the correlation curve between the resistance change ratio and the test time is smooth after 60 seconds, which can prove that the thin film resistor of the present invention can reduce the influence of electrochemical corrosion and stabilize the resistance value of the thin film resistor.

In summary, the thin film resistor of the present invention is composed of a metal with low activity. The protective layer or coating that protects the resistor. With the metal or metal oxide that is not affected by electrochemical corrosion, it can prevent the film resistor from being corroded and change the resistance value. It has the effects of stabilizing the resistance value, reducing the thickness of the component, and improving the heat dissipation of the component. .

Although the present invention has been disclosed using the above-mentioned preferred embodiments, it is not intended to limit the present invention. Anyone who is familiar with the art without departing from the spirit and scope of the present invention may make various changes and modifications relative to the above-mentioned embodiments. The technical scope of the invention is protected. Therefore, the scope of protection of the invention shall be subject to the scope of the attached patent application.

1‧‧‧Substrate

11‧‧‧Electrode

2‧‧‧Resistance layer

3‧‧‧Metal protective layer

S‧‧‧Loading surface

Claims (4)

A thin film resistor, comprising: a substrate with a bearing surface; a resistance layer located on the bearing surface; and a metal protective layer located on the other surface of the resistance layer opposite to the bearing surface, the metal protective layer made of hafnium , Tungsten, silver, platinum, palladium, ruthenium or alloys of the above elements. For the thin film resistor described in item 1 of the scope of patent application, wherein the resistor layer is a nickel-chromium alloy or a chromium-silicon alloy. The thin film resistor described in item 1 or 2 of the scope of patent application, wherein the substrate has two electrode portions, the two electrode portions are respectively located at two ends of the carrying surface, and the resistance layer is electrically connected to the two electrode portions respectively. The thin film resistor described in item 1 or 2 of the scope of patent application, wherein the thickness of the resistor layer is less than 10 microns.

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