This application claims priority of Taiwanese Patent Application No. 104117423, filed on May 29, 2015.
The disclosure relates to a method for manufacturing a resistor device, more particularly to a method for manufacturing a thin film chip resistor device.
Resistors are used for reducing voltage or limiting current flow. Chip resistor devices can generally be classified into thick film chip resistor devices and thin film chip resistor devices. The thick film chip resistor devices normally have a film thickness larger than 5 μm and are usually made by silk screen printing techniques. The thin film chip resistor devices normally have a film thickness smaller than 1 μm and are usually made by chemical vapor deposition techniques or physical vapor deposition techniques such as vacuum evaporation, magnetron sputtering, etc., in combination with photolithography.
During photolithography, a resistor layer is first formed on a substrate, followed by etching the resistor layer with the use of a patterned photoresist to obtain a chip resistor device with a desired resistor value. However, a developer used in the photolithography process is toxic and may be harmful to equipment operators and the environment. Moreover, the equipment and maintenance costs are rather high.
In an alternative method, a mask with a predetermined pattern is formed on a substrate by screen printing techniques, followed by depositing a resistor layer on the substrate. However, the mask formed by screen printing techniques tends to deform and cause an undesired resistor value shift. Furthermore, the mask must be removed by use of chemicals, which contributes to increased levels of environmental pollution.
Therefore, an object of the present disclosure is to provide a method for manufacturing a thin film chip resistor device that can alleviate at least one of the aforementioned drawbacks associated with the conventional method.
According to an aspect of the present disclosure, a method for manufacturing a thin film chip resistor device includes the steps of:
disposing a magnetic fixing member on a first surface of a substrate, and disposing a magnetic shadow mask on a second surface of the substrate opposite to the first surface, such that the magnetic shadow mask detachably and fixedly contacts the second surface of the substrate by virtue of an attractive magnetic force between the magnetic fixing member and the magnetic shadow mask; and
depositing at least one resistor unit on the second surface of the substrate with the use of the magnetic shadow mask, the resistor unit including two separated first electrode elements and a resistor element that electrically interconnects the first electrode elements.
Other features and advantages of the present disclosure will become apparent in the following detailed description of the embodiments with reference to the accompanying drawings, of which:
Before the disclosure is described in further detail with reference to the accompanying embodiments, it should be noted herein that like elements are denoted by the same reference numerals throughout the disclosure.
Referring to
Referring to
Next, in the mask disposing step 11, a magnetic fixing member 32 is disposed on the first surface 211 of the substrate 21, and a first magnetic shadow mask 311 is disposed on the second surface 212 of the substrate 21, such that the first magnetic shadow mask 311 detachably and fixedly contacts the second surface 212 of the substrate 21 by virtue of the attractive magnetic force between the magnetic fixing member 32 and the first magnetic shadow mask 311. Afterwards, the magnetic fixing member 32, the first magnetic shadow mask 311 and the substrate 21 are fixed with the fixture unit 33.
In the resistor unit depositing step 12, at least one resistor unit 24 is deposited on the second surface 212 of the substrate 21. The resistor unit 24 includes two separated first electrode elements 241 and a resistor element 242 electrically interconnecting the first electrode elements 241. In this embodiment, a plurality of resistor units 24 are deposited on the second surface 212. Specifically, as shown in
Next, as shown in
After the formation of the electrode pads 241′, each of the resistor elements 242 may be cut (i.e., by using laser cutting) to obtain a desired resistor value. The adjustment of the resistor value is well-known in the art and additional elaboration thereof will thus not be provided hereinafter for the sake of brevity. It should be noted that, according to practical requirements, the electrode pads 241′ may be formed first, followed by forming the resistor strips 242′.
Referring to
In the dicing step 13, the assembly is first diced along the first imaginary dicing lines (X) and the second imaginary dicing lines (Y) so as to form a plurality of chip resistor semi-products 40, each of which includes a respective one of the resistor units 24 (see
Referring to
Note that each protective unit 25 protects the resistor element 242 of a corresponding resistor unit 24 from collision and contamination in the course of manufacturing. The protective units 25 may be formed after the resistor unit depositing step 12 (as mentioned above) or after the dicing step 13. In each thin film chip resistor device 5, a top surface of the protective unit 25 is lower than a top surface of the plated unit 27, so that the plated metal laminates 271 of the plated unit 27 can be in direct and electrical contact with a circuit board (not shown) without structural hindrance.
It should be pointed out that the first and second magnetic shadow masks 311, 312 may be independently made of a magnetic material, e.g., iron, cobalt or nickel. The magnetic fixing member 32 may be a permanent magnet or a temporary magnet. The shape of the magnetic fixing member 32 may be changed according to the shapes of the first and second magnetic shadow masks 311, 312 so as to achieve superior attractive magnetic force between the magnetic fixing member 32 and the first and second magnetic shadow masks 311, 312. The resistor element 242 of each of the resistor units 24 may be made of a material, e.g., nickel-chromium alloy, nickel-chromium-aluminum alloy, nickel-chromium-silicon alloy, chromium-silicon alloy, manganese-copper-nickel alloy, manganese-copper-tin alloy, or manganese-aluminum alloy. The first electrode elements 241 of each of the resistor units 24 may be made of a material, e.g., silver, copper or gold. The protective units 25 may be made of epoxy resin or acrylic resin.
Note that the magnetic fixing member 32, the magnetic shadow mask and the substrate 21 are fixed with the fixture unit 33 by means of screw locking, interlocking, etc. The fixture unit 33 is used for increasing deposition precision and may be omitted according to practical requirements.
It should be noted that, in the first embodiment, the dicing step 13 may be omitted when manufacturing a single thin film chip resistor device 5 rather than multiple thin film chip resistor devices 5.
Referring to
The substrate used in the second embodiment has a structure identical to that of the first embodiment.
Referring to
The mask disposing step 62 and the resistor unit depositing step 63 in the second embodiment are the same as the mask disposing step 11 and the resistor unit depositing step 12 in the first embodiment.
In the first dicing step 64, the substrate 21 is diced along the first imaginary dicing lines (X) to form a plurality of substrate blocks (not shown).
Referring to
In the second dicing step 66, the substrate blocks are diced along the second imaginary dicing lines (Y) to form a plurality of chip resistor semi-products 40.
The plated unit forming step 67 in the second embodiment is similar to the plated unit forming step 14 in the first embodiment except that, in the plated unit forming step 67, the plated unit 27 is formed on a respective one of the chip resistor semi-products 40 such that each of the plated metal laminates 271 of the plated unit 27 covers and electrically contacts a respective one of the first electrode elements 241, the respective one of the connecting elements 261 and the respective one of the second electrode elements 231.
Similar to the first embodiment, the second embodiment may also include the step of forming the protective units 25. In the second embodiment, based on actual requirements, the step of forming the protective units 25 may be conducted before the first dicing step 64, between the first and second dicing steps 64, 66, or after the second dicing steps.
Note that either the first electrode elements 241 or the second electrode elements 231 of a respective one of the thin film chip resistor devices 7 can be used for electrically contacting the circuit board via a respective plated unit 27. In each thin film chip resistor device 7, when the second electrode elements 231 are used for electrical connection, a top surface of the protective unit 25 may be higher than a top surface of the plated unit 27.
It should be noted that, in the second embodiment, the first and second dicing steps 64, 66 may be omitted when manufacturing a single thin film chip resistor device 7 rather than multiple thin film chip resistor devices 7.
To sum up, with the use of the magnetic fixing member 32, and the first and second magnetic shadow masks 311, 312, the resistor units 24 can be formed with precise shapes and at precise locations.
While the disclosure has been described in connection with what are considered the exemplary embodiments, it is understood that this disclosure is not limited to the disclosed embodiments but is intended to cover various arrangements included within the spirit and scope of the broadest interpretation so as to encompass all such modifications and equivalent arrangements.
Number | Date | Country | Kind |
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104117423 A | May 2015 | TW | national |
Number | Name | Date | Kind |
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5604383 | Matsuzaki | Feb 1997 | A |
5699025 | Kanoh | Dec 1997 | A |
7420786 | Sugiyama | Sep 2008 | B2 |
20070247268 | Oya | Oct 2007 | A1 |
20080107873 | Kuwajima | May 2008 | A1 |
Number | Date | Country |
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4013858 | Jan 1992 | JP |
Number | Date | Country | |
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20160351307 A1 | Dec 2016 | US |