TWI910048B - Silver-plating process for wafers - Google Patents

Abstract

This invention relates to a method for a passive component silver plating process, which can improve the stability of electronic product quality. The method mainly involves transferring several chips into a second substrate, then pressing a first corner of the chip against the substrate using an offset pin to expose it; then applying silver plating to the first corner and drying it; then pressing the first corner into the second substrate using a roller; then transferring the chip from the second substrate into a third substrate using an ejector pin; then pressing a second corner of the chip against the substrate using an offset pin to expose it; then applying silver plating to the second corner of the chip and drying it; finally, pressing the chip out of the third substrate using an ejector pin to complete the entire silver plating process.

Description

Silver-plating process for wafers

This invention relates to the field of passive component manufacturing processes, and more particularly to a technique for a wafer oblique silver plating process.

Note that the ag dipping technique for passive components is mainly used to enhance the conductivity of the electrodes, improve solderability, and increase reliability. This technique is widely used in ceramic capacitors (MLCCs), piezoelectric elements, resistors, and sensing elements.

However, with the rapid development of modern electronic technology and the emergence of increasingly thin and small electronic products, the size of ceramic cores is required to be smaller and smaller, and the flat silver plating technology is no longer sufficient to meet the needs. Furthermore, because oblique silver plating of ceramic core electrodes can overcome the instability caused by temperature differences and vibrations within electronic products, thereby improving the stability of the electronic product and improving the accuracy of inductance values, it is possible to make a large number of electronic 3C products smaller, more refined, and more affordable. However, related technologies for oblique silver plating of chips are not yet available on the market and are in great need of development.

Therefore, the inventors have devoted themselves to developing the wafer oblique silver plating process of the present invention. Thus, the primary objective of the present invention is to provide a wafer oblique silver plating process that improves the stability of electronic product mounting; the secondary objective of the present invention is to provide a wafer oblique silver plating process with the fewest process steps.

To achieve the above objectives, the present invention relates to a wafer oblique silver-coating process using the following technical means, comprising: an implantation loading step, in which several wafers are transferred from a first substrate and embedded into the interior of a second substrate; a tilting protrusion step, in which several offset flat pins are inserted and pressed against one side of the wafers located in the second substrate to create an oblique effect, and each first corner of the wafers protrudes from the second substrate; a first silver-coating and drying step, in which each first corner of the wafers is silver-coated and dried; and a rolling flattening step, in which at least one roller is used to roll the silver-coated first corners of the wafers. The process involves pressing the wafers into the interior of the second substrate; a blanking step, in which the second substrate and a third substrate are stacked on top of each other, and several ejector pins are used to transfer the wafers from the second substrate into the interior of the third substrate; a convex turning step, in which several offset pins are used to press against the other side of the wafers to create a tilting effect, and the second corners of the wafers protrude from the third substrate; a second silver coating and drying step, in which the second corners of the wafers are coated with silver and dried; and an unloading step, in which several ejector pins are inserted into the third substrate and the wafers are pressed out of the third substrate.

The first carrier plate is a guide plate, while the second and third carrier plates are both thin plastic sheets.

The head width of the offset flat needle is smaller than the head width of the protruding flat needle.

In the implantation and loading step, the chips are located at the top or bottom edge of the second substrate.

In the implantation loading step, the first carrier plate is located below the second carrier plate, and several punch groups are provided below the first carrier plate, which correspond to the several chips located in the first carrier plate.

In the empty board step, the chips are located at the top or bottom edge of the third carrier board.

In the empty board step, the third carrier board is located below the second carrier board, and the second carrier board has several ejector pins on top of it that correspond to the several chips located inside the second carrier board.

In the downward convex step, the wafers are tilted around a first fulcrum.

In the turning convex step, the chips are tilted at a second fulcrum.

In the rolling process, two rollers are placed on and in contact with the upper and lower edges of the second carrier plate to roll into the edge for alignment.

By employing the aforementioned technical means, this invention can achieve the following effects:

1. The manufacturing process of this invention mainly provides oblique silver plating on the bottom of the two electrodes of passive components and related chips. The aforementioned chips and their oblique silver-plated electrodes can overcome the instability caused by temperature differences and vibrations within electronic products, thereby improving the stability of the electronic product quality and simultaneously improving the accuracy of inductance values, making a large number of electronic 3C products smaller, more refined, and more reasonably priced.

2. The process method of this invention is the process method with the fewest steps, thereby simplifying the complexity of the device mechanism of the automatic silver plating machine.

This invention relates to a method for oblique silver plating of a wafer, as shown in Figures 1 and 2. It mainly provides a method for plating silver onto the first corner 41 and second corner 42 of the two electrodes 40 of a passive component wafer 4, thereby improving the stability of its quality and that of electronic products. The oblique silver plating process A includes: an implantation loading step a, a downward rotating convex... Step b, a first silver-dip drying step c, a rolling flattening step d, a turning empty plate step e, a turning convex step f, a second silver-dip drying step g, and a unloading step h; the above process steps are explained below with reference to the diagrams. In particular, the diagrams of this invention use larger chip 4 and chip 4a as examples, arranged on both sides of a two-point chain for illustration.

As shown in Figures 1 and 3, the implantation step a involves transferring several chips 4 (or chips 4a) arranged in a two-dimensional matrix from a first carrier plate 1 into the interior of a second carrier plate 2. The first carrier plate 1 is a guide plate, and the second carrier plate 2 is a thin carrier plate (TCP). The first carrier plate 1 is positioned below the second carrier plate 2. Below the first carrier plate 1, there are several punch groups 5 that correspond to the chips 4 (or chips 4a) located within the first carrier plate 1. That is, the punch groups 5 are also arranged in a two-dimensional matrix to facilitate the transfer of the chips 4 (or chips 4a) from the position of the first carrier plate 1 into the position of the second carrier plate 2. The positions of the chips 4 inside the second substrate 2 are different from the positions of the chips 4a inside the second substrate 2. In other words, the upper edge 21 of the chips 4 inside the second substrate 2 is aligned with the upper edge 21, while the lower edge 22 of the chips 4a inside the second substrate 2 is aligned with the upper edge 22.

As shown in Figures 1 and 4, step b involves inserting several offset pins 6 arranged in a two-dimensional matrix downwards and pressing them against one side of several chips 4 (or chips 4a) located within the second substrate 2, thereby tilting them and exposing the first corners 41 of each chip 4 to the second substrate 2. Each chip 4 is tilted and rotated approximately around a first fulcrum 23, and the chips 4a are also tilted and rotated approximately around a first fulcrum 23, and are thus exposed.

The first silvering and drying step c, as shown in Figures 1 and 5, involves silvering and drying the first edges 41 of the several wafers (or wafers 4a) that are protruding from the second substrate 2. The silvering method is as follows: the second substrate 2 is moved directly above a silvering tank 9, then moved directly downwards until the aforementioned first edges 41 are immersed in the silver liquid 91 inside the silvering tank 9, and then returned to the position directly above the silvering tank 9. Then, the second substrate 2 is moved to a drying oven to dry the aforementioned silvered areas.

As shown in Figures 1 and 6, the rolling step d involves using at least one roller 7 to move to one side of the dried second carrier plate 2, and then using the at least one roller 7 to press the silver-coated first edges 41 of the plurality of wafers 4 (or wafers 4a) into the interior of the second carrier plate 2 by rolling. A preferred method for this step is to use two rollers 7 respectively placed on and in contact with the upper edge 21 and lower edge 22 of one side of the second carrier plate 2 to roll and cut the silver-coated first edges 41 into the upper edge 21.

As shown in Figures 1 and 7, the empty board transfer step e involves stacking the second carrier board 2 and the third carrier board 3 on top of each other, and then using several ejector pins 8 arranged in a two-dimensional matrix to transfer the chips 4 (or chips 4a) from the second carrier board 2 and embed them into the upper edge 31 (or lower edge 32) inside the third carrier board 3. The position of the chips 4 inside the third carrier board 3 is different from the position of the chips 4a inside the third carrier board 3. In other words, the upper edge 31 of the chips 4 inside the third carrier board 3 is aligned with the upper edge 31, while the lower edge 32 of the chips 4a inside the third carrier board 3 is aligned with the upper edge 31. In this embodiment, the third carrier board 3 is also a TCP thin film board, and the second carrier board 2 is located above the third carrier board 3, so that the several ejector pins 8 are inserted from above the second carrier board 2 to move the several chips 4 (or chips 4a) located inside the second carrier board 2 to the upper edge 31 (or lower edge 32) inside the third carrier board 3.

As shown in Figures 1 and 8, the turning convex step f is similar to the turning convex step b. It involves several offset pins 6 arranged in a two-dimensional matrix pressing against the un-silvered sides of the wafers 4 (or wafers 4a), creating a tilting effect and exposing the second corners 42 of each wafer 4 (or wafer 4a) to the third substrate 3. Specifically, the wafers 4 are tilted and rotated approximately around a second fulcrum 33, and the wafers 4a are also tilted and rotated approximately around a second fulcrum 33, and thus exposed.

The second silvering and drying step g, as shown in Figures 1 and 9, is the same as the first silvering and drying step c. It involves silvering and drying each of the second edges 42 of the chips 4 (or chips 4a). Specifically, the third carrier plate 3 is moved directly above the silvering tank 9, then moved directly downwards until the silver liquid 91 inside the silvering tank 9 is immersed in the aforementioned second edges 42. It is then returned to the position directly above the silvering tank 9, and then the third carrier plate 3 is moved to a drying oven to dry the aforementioned silvered areas.

As shown in Figures 1 and 10, in the unloading step h, several ejector pins 8 arranged in a two-dimensional matrix are inserted into the third carrier plate 3, and the several wafers 4 (or wafers 4a) are pressed out of the third carrier plate 3. It should be noted that the head width of the offset pin 6 is usually smaller than the head width of the ejector pin 8.

Therefore, this invention provides a better solution for a wafer oblique silver plating process, thereby improving the stability of the wafer and its quality in electronic products. The main process involves transferring several wafers 4 (or wafers 4a) from the first substrate 1 and embedding them into a second substrate 2. Then, several offset pins 6 are used to press all the first edges 41 of the electrodes 40 at both ends of the wafers 4 (or wafers 4a) so that they protrude from the second substrate 2. Next, all the first edges 41 are silver-plated and dried. Finally, rollers 7 are used to press all the first edges 41 into the substrate by rolling. Inside the second substrate 2; then, the several ejector pins 8 are used to transfer the several chips 4 (or chips 4a) from the second substrate 2 and embed them into a third substrate 3; then, the several offset pins 6 are used to press all the second edges 42 of the several chips 4 (or chips 4a) so that they protrude from the third substrate 3; then, all the second edges 42 of the several chips 4 (or chips 4a) are dipped in silver and dried; finally, the several ejector pins 8 are used to press the several chips 4 (or chips 4a) out of the third substrate 3 to complete the entire silver plating process.

In conclusion, this invention relates to a method for oblique silver plating on wafers, and the above-mentioned process steps and methods have not been seen in any books or publicly used. It truly meets the requirements for an invention patent application. We earnestly request the Bureau of Technology to review this invention and grant the patent as soon as possible. We are deeply grateful.

It should be stated that the above-described technical principles are those used in the specific implementation of this case. Any changes made in accordance with the concept of this case, provided that their functions and effects do not exceed the spirit of this specification and drawings, shall be stated within the scope of the patent application in this case.

A: Wafer Angled Silver Dipping Process a: Implantation Loading Step b: Turning Downward Convex Step c: First Silver Dipping and Drying Step d: Rolling Flattening Step e: Turning Empty Plate Step f: Turning Toward Convex Step g: Second Silver Dipping and Drying Step h: Unloading Step 1: First Carrier Plate 2: Second Carrier Plate 21: Upper Edge 22: Lower Edge 23: First Support Point 3: Third Carrier Plate 31: Upper Edge 32: Lower Edge 33: Second Support Point 4: Wafer 40: Electrode 4a: Wafer 41: First Corner 42: Second Corner 5: Punch Pin Assembly 6: Offset Flat Pin 7: Roller 8: Ejector Flat Pin 9: Silver Dipping Tank 91: Silver Liquid

[Figure 1] Flowchart of the wafer oblique silver plating process of the present invention. [Figure 2] Schematic diagram of the appearance of the wafer after the completion of the silver plating process of the present invention. [Figure 3] Schematic diagram of the implantation loading step of the present invention. [Figure 4] Schematic diagram of the turning-down bump step of the present invention. [Figure 5] Schematic diagram of the first silver plating drying step of the present invention. [Figure 6] Schematic diagram of the rolling flattening step of the present invention. [Figure 7] Schematic diagram of the empty board turning step of the present invention. [Figure 8] Schematic diagram of the turning-up bump step of the present invention. [Figure 9] Schematic diagram of the second silver plating drying step of the present invention. [Figure 10] Schematic diagram of the unloading step of the present invention.

A: Silver plating process for wafers (oblique application)

a: Implantation procedure

b: Turn down the convex step

c: First silver-dipped and dried step

d: Rolling flat step

e: Steps to switch to an empty board

f: Turning step

g: Second silver coating and drying step

h: Unloading steps

Claims (10)

A method for oblique silver plating of wafers includes: an implantation loading step, in which several wafers are transferred from a first substrate and embedded into the interior of a second substrate; a tilting protrusion step, in which several offset flat pins are inserted and pressed against one side of the wafers located in the second substrate to create an oblique effect, and the first corners of the wafers protrude from the second substrate; a first silver plating and drying step, in which the first corners of the wafers are silvered and dried; and a rolling flattening step, in which the silvered first corners of the wafers are pressed into the interior of the second substrate by rolling using at least one roller. The process includes: a first step of transferring the wafers to a blank substrate, where the second substrate and a third substrate are stacked on top of each other, and several ejector pins are used to transfer the wafers from the second substrate into the third substrate; a second step of tilting the wafers, where several offset pins are used to press against the other side of the wafers to create a tilting effect, and the second corners of the wafers protrude from the third substrate; a second step of silvering and drying the wafers, where the second corners of the wafers are silvered and dried; and a third step of unloading the wafers, where several ejector pins are inserted into the third substrate to push the wafers out of the third substrate. The wafer oblique silver-plating process method as described in claim 1, wherein the first substrate is a guide plate, and the second and third substrates are both thin adhesive plates. The wafer oblique silver-plating process method as described in claim 1, wherein the head width of the offset flat needle is smaller than the head width of the ejector flat needle. The wafer oblique silver-coating process method as described in claim 1, wherein in the implantation loading step, the plurality of wafers are located at the top or bottom edge of the second substrate. The wafer oblique silver-coating process method as described in claim 1 or 4, wherein in the implantation loading step, the first carrier plate is located below the second carrier plate, and a plurality of punch groups are provided below the first carrier plate corresponding to the plurality of wafers located within the first carrier plate. As described in claim 1, in the wafer oblique silver-plating process method, in the empty plate step, the plurality of wafers are located at the top or bottom edge of the third carrier plate. As described in claim 1 or 6, in the wafer oblique silver plating process method, in the empty plate step, the third carrier plate is located below the second carrier plate, and the second carrier plate is provided with several ejector pins above it, which correspond to the several wafers located in the second carrier plate. The wafer tilting silver plating process method as described in claim 1, wherein in the under-bump step, the plurality of wafers are tilted at a first fulcrum. The wafer tilting silver plating process method as described in claim 1, wherein in the turning convex step, the plurality of wafers are tilted at a second fulcrum. As described in claim 1, in the wafer oblique silver plating process method, in the rolling flat step, two rollers are respectively placed on and in contact with the upper and lower edges of the second substrate to perform rolling into the cut.