TWI259635B - Terminal electrode forming method of a circuit protection unit and its product - Google Patents

Abstract

A terminal electrode forming method of a circuit protection unit and its product are disclosed. First, form a protection layer in the middle position of the upper surface and the lower surface of the metal substrate as the resistance material, and leave the two ends of the metal substrate exposed. Then, use the powder metallurgical process to form electrodes on the two ends of the metal substrate, enabling the electrodes to have arbitrary shapes to meet the requirement for every different circuit. Hence, the overall characteristics is promoted.

Description

[Technical Field] The present invention relates to a terminal electrode shape of a circuit protection component: a method and a product thereof, which are formed by first forming a protective layer of a metal substrate upper and lower surfaces The middle position, and the two ends of the metal substrate are exposed, and then the two of the metal substrate: using the powder metallurgy process to form the terminal electrode, so that the terminal electrode can be arbitrarily shaped to suit various circuits. The overall use characteristics. [Prior Art] In order to ensure circuit safety during general circuit design, circuit protection components such as resistors and fuses are added to the circuit. Port diagram 1 'is a conventional thick film wafer resistor i of a circuit protection component, C. A ceramic substrate 11 as a substrate, a resistive film 12 covered with a screen printing on a ceramic substrate, and two squares: a ceramic substrate 11 on both sides and the end face of the resistor 臈12 and the protective layer 14 overlying the resistive film 12. For a large number of manufacturing, as shown in Fig. 2, the chip resistor is manufactured in a large volume. The ceramic plate 1 〇 last formed a plurality of matrix-like and discrete resistors. However, as shown in the figure, the two Si end surface electrodes 13 of the film 12 and the protective layer 14 on the ceramic substrate 11 are respectively located on the two sides 4 of the ceramic substrate 11. Therefore, after the manufacturing of the resistor film 1259635 and the edge-preserving layer 14, it is necessary to divide the ceramic plate 1 , so that the side edges of the respective resistors are exposed to form the end face electrode. Generally, the ceramic plate is separated by a physical fracture along the line 彳〇1 of the ceramic plate, for example, the plate is separated, and the whole ceramic plate 10 is separated into strips having a plurality of connected resistances (for example, 0 3) or the parent resistors are independent of each other to expose the side edges of all circuit protection components, and then connect the front and back sides with copper or silver. ,

Then, since the ceramic plate 1〇 has been divided into strips 1〇2 or blocks in this case, the end face electrodes 13 are mostly formed by barrel plating. Generally, the thickness of 〇_〇5~〇.imm can be plated for 5 to 9 hours after barrel plating, resulting in a more lengthy manufacturing process of conventional resistors.

Moreover, the conventional chip resistor 1 is required to be baked at a high temperature during the manufacturing process. For example, as disclosed in the Patent No. 8681 1 31 62, the resistive film 12 is printed on the Tauman substrate 1 in the step of forming the resistive film 彳2. After the 'drying, high temperature (such as) sintering process can be formed, and in the process of the end face electrode 13, the copper electrode paste is first placed on both sides of the ceramic plate 10, and then baked at a high temperature (such as 80 CTC) The time (e.g., 1 minute) can form the vertical electrode 13 .咏Because the conventional chip resistor 1 needs high temperature baking during the manufacturing process, 'm 1〇 size slightly A' (four) cold shrinkage caused by the flatness problem will be quite obvious 'the yield will drop suddenly, the price is thus large 6 1259635 The lifting makes the common size of the target only about 1 〇* 1 〇cm, so when using the ceramic substrate, the number of components manufactured each time is limited.

Moreover, the resistive film 12 of the thick film resistor is formed by printing, the thickness of the resistive film 12 is easily uneven, and the variation of the f-resistance diffusion and the sintering temperature is caused, so that the thick film crystal resistance 1 The resistance value varies greatly. Especially when applied to a high-frequency environment, the resistive film of the thick film chip resistor 1 has a high aperture ratio and a loose structure, resulting in high frequency signal loss (丨ost), and thus is not suitable for the high frequency range. Moreover, a conventional fuse is also a fuse including a substrate, a square, and a substrate - a protective layer covering the fuse portion and an end surface electrically formed at both ends of the substrate by means of station silver and barrel plating. Therefore, conventional fuses also have the drawback of lengthy process. SUMMARY OF THE INVENTION In view of the drawbacks of conventional circuit protection components, the present invention directly uses a metal substrate as a resistance layer or a fuse portion, so as to omit the conventional steps of forming a metal film as a resistor or a fuse portion on a germanium substrate, and (4) The final gold process to form the terminal electrode to solve the aforementioned problems. SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide an electrode forming method for a circuit-protected 4-element in which a thin electrode of a circuit protection element is formed by a powder metallurgy process so that it can be in any arbitrary shape to respond to different circuits. Needed. 7 1259635 The second object of the present invention is to form a perforation on a metal plate and to divide it after forming the terminal electrode, thereby achieving the simplification of the manufacturing process. Another object of the present invention is to provide a method for forming a terminal electrode of a circuit protection component, which directly uses a metal substrate as a resistor layer or a fuse portion to achieve a simplified structure and a shortened process.

Still another object of the present invention is a metal substrate for forming a terminal electrode of a device as a resistance effect. The present invention provides a circuit protection 'too uniform thickness and structure' to achieve a suitable high frequency environment. Thus, the method for forming a terminal electrode of a circuit protection component of the present invention comprises the following steps:

Step A) forming a protective layer 'in the middle of the upper and lower surfaces of a metal substrate to make the two ends of the metal substrate bare; and (1) forming a powder metallurgical process on both ends of the metal substrate End face electrode. The above and other technical contents, features, and advantages of the preferred embodiments of the present invention will be apparent. [Embodiment] The method of forming the terminal electrode of the circuit protection element of the present invention, 8 1259635 is shown in Fig. 4. For convenience of explanation, in the present embodiment, a circuit protection element fabricated as a chip resistor will be described first. Further, since the wafer resistance is mass-produced, the present embodiment is described by manufacturing a plurality of wafer resistors in a single pass. First, in step 20, a metal plate 3 as shown in FIG. 5 is provided to directly utilize the metal plate 3 as a resistive layer in the chip resistor. In this embodiment, the material of the metal plate 3 is a small temperature coefficient of resistance. The resistance material, for example, the resistance temperature is in the range of 10 ppm/t to 20 〇 ppm c. The material of the metal plate 3 of this example may be nickel-chromium alloy, nickel-steel alloy, iron-nickel alloy or manganese-copper alloy, etc., depending on the needs of the tenth. The thickness of the metal plate 3 of this example is about 〇-〇5mm~〇.8mm and the width is about 1C)mm~

1 000m, and the length depends on the number of wafer resistors to be formed. For example, if the length is 1 〇〇〇 coffee and the metal plate 3 having a width of 650 mm can form about 5,000 to 2 晶片 wafer resistance. ^ Next, in step 21, as shown in FIG. 6, the perforations 31 are arranged in a matrix on the metal plate 3 to form a plurality of laterally extending resistive strips (referring to metal strips) 32. Thus, each of the resistive strips has a plurality of The perforation 31 and a plurality of metal base plates 33 respectively located between the two perforations. The metal substrates 33 are used to form a wafer resistance. In this example, the perforations 31 are formed by stamping, the perforation size is 0.15 mm to 30 mm, and two adjacent perforations 31 are formed. The distance between the 1259635 is 0e15mm~1〇mm, and the distance between the two rows of perforations 31 is 0.15mm~30mm. In addition, in order to facilitate the positioning of the metal plate 3 on the subsequent process equipment, when the perforation 31 is formed, The position of the metal plate 3 and the metal plate 33 are staggered (for example, on the upper and lower sides of the resistor bar 32) to form a plurality of positioning holes 34 for positioning of the process equipment. It should be noted that in this example, The financial (4) is formed into the perforation 31 and the positioning hole 34. However, it is known to those skilled in the art that the technology can be formed by etching, and is not limited to those disclosed in the embodiment. In order to increase the metal substrate 33 and protect it. Lamination, the chip resistance of this example is more In step 22, as shown in Fig. 7, the adhesive layer 35 is formed at a centering position of the upper and lower surfaces of the sub-substrate 33. In this example, the sign is provided for the ^^^ station layer 35 can be sputtered and steamed. Plating, chemical plating method is formed and 1 from the New Zealand, the wind 1 material can be selected according to the material i of the metal plate 3, such as copper, nickel, tin, silver or a metal alloy, etc., ^ m 〇, . ; degree is about 1 from m to 50 β m. In addition, since the adhesion layer 35 is inflamed into η λ, the metal substrate 33 and the accompanying ': wide material' are removed to eliminate the bonding strength between the layers. , f is used to adjust the resistivity, f number, etc. In addition, if the gold: resistance, resistance temperature, the bonding strength between the layers is sufficient, the applied material and protection 22 can be omitted. ^ The step of forming the adhesive layer 35 is followed by In step V23, as shown in FIG. 8 and FIG. 9, a protective layer 36 covering the adhesive layer 35 is formed at a centering position of each of the upper and lower surfaces of the substrate 3333, so that the metal substrate 33 is bare and bare. The protective layer 36 of this example functions as an insulation and a bar. Further, in this example, as shown in FIG. In addition to being formed on the upper surface of the metal substrate 33, in order to protect the left and right sides of the center position of each metal substrate 33 (refer to the peripheral wall of the through hole 31), it is necessary to have a protective layer on the left and right sides of the metal substrate 31. 36. Therefore, in this example, the through hole 31 is designed in a cross shape, so that the material of the protective layer 36 easily flows into the through hole 31 during the formation of the protective layer 36, so that the protective layer 36 covers the center of each metal substrate 33, The lower surface and the left and right sides. The protective layer 36 in this example is made of epoxy resin (Epoxy) and Epoxy Molding Compounds (Fused HCa) 'having a thickness of 1 mm to 1 mm. Next, in step 24, as shown in Figs. 11 and 2, a metal layer 37 is formed on the upper and lower surfaces of both ends of each of the substrate substrates 33 as a terminal electrode. Then, in step 25, the metal plate 3 is cut so that the plurality of metal substrates 33 are independent and can function as a wafer resistor (Fig. 13). The metal plate 3 can be stamped, chemically etched, formed into a dividing line on the metal plate 33, and physically divided into a metal plate. 3 Field cutting or diamond cutting, etc., and the cutting method is selected according to design requirements. 1259635 Lai'an = conductive brush circuit board such as tin, in order to strengthen the conductive adhesive between the conductive paste and the electrode, this example is further in step 26, as shown in Figure 14, forming a cladding metal substrate 33 The metal 臈% at both ends, 'covers the metal layer 37 and the metal substrate % at both ends: the adhesion between the chip resistor and the printed circuit board can be effectively avoided. In this example, the metal film 38 is a nickel-tin metal film and Thick production = 〇〇5mm~0.02mm. Furthermore, since the metal plate is already divided and the thickness of the metal film 38 is much smaller than that of the metal layer 37, the metal film 38 is formed by rolling metal on each metal substrate.

Both ends. Therefore, as shown in FIG. 14, the wafer resistor of the present embodiment includes a metal substrate 33, a protective layer 36 formed on the upper and lower surfaces of the centering position of the metal substrate 33, and formed on both end faces of the metal substrate 33 and composed of the metal layer 37 and the metal. The membrane 38 constitutes an electrode. ❿ ^ The above-mentioned metal layer 37 formed on both sides of the metal substrate 33 is formed by a metallurgical process by a metallurgical process on a bare end surface of the copper powder. Since the metal layer 37 is formed by a metallurgical process, it is not limited to The surface of the metal substrate 33 protrudes toward the side or the upper and lower sides of the substrate, and can be made into any J shape to meet the requirements of different circuits. As shown in FIG. 15, a first embodiment of an electrode of a circuit protection component of the present invention is shown by the figure, which is 12 Ϊ 259635 and the electrode is a square-shaped end face electrode 4 face 41 and a lower end face 42 slightly t The upper end 36 of the terminal electrode 4, the protective layer 43 of the metal substrate 33 at the side end thereof protrudes from the portion of the metal substrate 33, and belongs to the substrate 33 so as to be convexly bonded to the printed circuit board. Bending, so as to be set as a pin as shown in Fig. 16. The second embodiment of the electrode of the electrode, the terminal electrode of the circuit protection component of the s is a long end terminal: 5: as indicated by the figure The second electrode 5 of the armpit 5 causes the upper end surface of the end electrode 5 to be long, and is recessed inwardly and the outer end of the end electrode 5 is extended to extend the portion of the metal sheet which is extended by the metal sheet. The high pins can be combined on a board that requires a higher degree of return. As shown, the third embodiment of the terminal electrode of the circuit protection component of the present invention is shown by way of example only, and is represented by the illustration, and the electrode is in the shape of a ring arc. The two ends of the spheroidal package=the base plate 33 are higher than the protective layer and are outwardly hooped, so that they have a large contact area after bending to meet the requirements of the relevant circuit. In summary, the present invention is formed by making the terminal electrode of the circuit protection component in a powder metallurgy process, and the shape thereof does not need to be limited to the height of the substrate or the height of the upper and lower end surface protective layers of the substrate, and can meet the needs of various circuits. And forming a pin that can be matched, which is also used as a fuse by a powder metallurgy process to form an end face electric 13 1359635 metal substrate. The term ":" is merely a preferred embodiment of the present invention, and Tian Yuexi limits the scope of implementation of the present invention, that is, the scope of application of the patent and the content of the invention description = early special effects change and repair, All should remain within the scope of the patent of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic cross-sectional view showing a conventional thick film wafer resistor; FIG. 2 is a schematic view showing a process of forming a protective layer of the wafer resistor of FIG. 1; FIG. 3 is a wafer of FIG. FIG. 5 is a schematic view of a metal plate of the embodiment of FIG. 4; FIG. 6 is a schematic view of a metal plate of the embodiment of FIG. FIG. 7 is a schematic view of a process for forming an adhesive layer in the embodiment of FIG. 4. FIG. 8 is a partial cross-sectional view of FIG. 8 showing a process for forming a protective layer in the embodiment of FIG. 4. FIG. FIG. 11 is a partial cross-sectional view of FIG. 11 in the embodiment of FIG. 4; FIG. 13 is a schematic view of a process of dividing the metal plate in the embodiment of FIG. 4 Process for forming a metal film in the embodiment 15 1559635 FIG. 15 is a first embodiment of the terminal electrode formed by powder metallurgy of the present invention; FIG. 16 is a second embodiment of the terminal electrode formed by powder metallurgy of the present invention. Figure, Figure 1 7 is the present invention A diagram illustrating a terminal electrode is formed of the end of the third embodiment is applied metallurgy. [Main component symbol description] • 3: metal plate 3 5 : adhesive layer 3 6 : protective layer 3 7 : terminal electrode 38 : metal film 2 〇 〜 26 : step 31 : perforation 32 : resistance bar 33 : metal substrate 34 : positioning Hole 4: square-shaped end surface electrode 41: upper end surface 42: lower end surface 43: side end surface 5: elongated end electrode 51: upper end surface 52: lower end surface 6: ring-arc shape terminal electrode 16

Claims (1)

259635 Patent Application Scope 1· A method for forming a terminal electrode of a circuit protection component includes the following steps: Step A) forming a protective layer at an intermediate position between the upper and lower surfaces of a metal substrate, respectively The bare end, and the step B) respectively form a terminal electrode by a powder metallurgy process at both ends of the metal substrate. 2. The terminal electrode forming method according to the first aspect of the invention, wherein the metal substrate in the step A) has a resistance temperature in the range of 10 to 20 〇 p p m / °C. 3. The method of forming a terminal electrode according to the invention of claim 2 or 2, wherein in the step A), the material of the metal substrate is selected from a nickel-chromium alloy, a nickel-copper alloy, an iron-nickel alloy, and a copper alloy. One of the alloy composition groups. The method for forming a terminal electrode according to the first aspect of the invention, further comprising a step 〇) before the step A), forming a position of the protective layer in the upper and lower surfaces of the metal substrate. An adhesive layer for reinforcing the bonding strength between the protective layer and the metal substrate. 5. The method of forming a terminal electrode according to item 4 of the patent scope of the invention, wherein the material of the adhesive layer is selected from the group consisting of copper, nickel, tin, silver and the aforementioned metal alloy. 259635 6 _ The method for forming a terminal electrode according to claim 1, wherein in the step B, a conductive metal layer is plated on the upper and lower surfaces of the two ends of the metal substrate, and then A tin-tin metal film is formed on the surface of the metal layer and the end surface of the metal substrate. The method of forming a terminal electrode according to claim 6, wherein the metal layer is made of copper. The end electrode structure of the circuit protection component comprises: a metal substrate having an upper surface, a surface opposite to the upper surface and both ends; a protective layer formed on the metal substrate, The lower surface is centered without covering both ends of the metal substrate and two end electrodes disposed at the ends of the substrate; wherein the terminal electrodes are formed by powder metallurgy. The terminal electrode described in the terminal electrode structure described in the eighth aspect of the patent application is a square shape. 10. The terminal electrode structure of claim 8, wherein the terminal electrode is in the shape of a strip. The end of the invention is in the form of a ring as described in the eighth paragraph of the patent application. 18