TWI666344B - Conductive ring, power supply device based on same, and electroplating fixture based on power supply device - Google Patents

Abstract

The invention discloses a conductive ring, a power supply device based on the same, and a plating fixture based on the power supply device. The conductive ring includes a conductive ring body, and the conductive ring body is a segmented structure distribution and is composed of multiple conductive segments; The opening between each adjacent two conductive segments is filled with insulating glue and separated by the insulating glue; the surface of the conductive ring body is covered with an insulating rubber layer; and the conductive ring body is provided with at least one electrode and at least One support foot. The conductive ring of the present invention is divided into multiple sections, and each section can independently perform current control, thereby ensuring the consistency and uniformity of the overall current distribution density of the wafer or printed circuit board, and ensuring the quality of the surface plating layer; A nickel plating layer and a silver plating layer are added on the body, thereby reducing the conductive impedance and enhancing the stability of the current transmission, thereby reducing the frequency of repairing and replacing the conductive ring body, and reducing the maintenance cost.

Description

Conductive ring, power supply device based on same, and electroplating fixture based on power supply device

The invention relates to the technical field of electroplating, and in particular to a conductive ring, a power supply device based on the same, and a plating fixture based on the power supply device.

During the production of semiconductor components (such as wafers or printed circuit boards), the surface needs to be plated. Taking a wafer as an example, it needs to be placed on a plating fixture. The wafer plating fixture is provided with Conductive rings. These conductive rings are in contact with the wafer on the wafer plating fixture. Therefore, the wafer on the wafer plating fixture can be connected to an external power source during the plating process, and the surface of the wafer can be decomposed by the decomposition of the plating solution. Form the required plating. However, in the actual electroplating process, it is very easy to have different coating thicknesses in different regions of the wafer. The main reason for the above problem is the deviation of the current density index in each region. Therefore, how to ensure the current distribution density in each region of the wafer Consistency has become a problem that technicians need to solve urgently.

In view of the shortcomings in the above technology, the present invention provides a conductive ring, a power supply device based on the same, and a plating fixture based on the power supply device. During the electroplating process, the semiconductor components such as wafers or printed circuit boards are divided into regional currents. Control to ensure a conductive ring with better current distribution density consistency.

To achieve the above object, the present invention provides a conductive ring including a conductive ring body. The conductive ring body is distributed in a segmented structure and is composed of multiple conductive segments. The openings between the conductive sections are filled with insulating glue and separated by the insulating glue; the surface of the conductive ring body is covered with an insulating rubber layer; and the conductive ring body is provided with at least one electrode and at least one supporting leg.

Wherein, the outer surface of the conductive ring body is sequentially provided with a nickel plating layer and a silver plating layer from the inside to the outside, and the silver plating layer is disposed between the nickel plating layer and the insulating rubber layer.

The thickness of the nickel-plated layer is 3 to 8 μm, and the thickness of the silver-plated layer is 15 to 30 μm; and the size of the cutout is 3 to 5 mm.

Wherein, the conductive ring body is made of stainless steel, and each of the conductive segments is provided with a plurality of the supporting legs, which are evenly distributed along a circumferential direction thereof.

In order to achieve the above object, the present invention further provides a power supply device based on a conductive ring, including a plurality of high-frequency switching rectifiers and the conductive rings as described above, and the number of the high-frequency switching rectifiers is the same as the number of conductive segments of the conductive rings; And the negative pole of each high-frequency switching rectifier is connected to the corresponding conductive segment; the positive pole of each high-frequency switching rectifier is connected to the anode plate; the conductive ring is connected to the semiconductor component, and the anode plate and the semiconductor component are between Electroplating solution; the high-frequency switching rectifier provides voltage and current to the entire circuit. Under the action of the voltage potential of the high-frequency switching rectifier, the anode plate dissolves metal cations into the plating solution, and the metal ions in the plating solution follow the direction of the power line to the semiconductor. The components move, and finally metal cations are precipitated on the semiconductor components to form a metal element, which completes the electroplating process.

Wherein, each high-frequency switching rectifier includes an anti-electromagnetic interference line filter, a rectifier, a filter, a high-frequency transformer, a high-frequency filter, a mos tube, a control chip, and a driver connected in order; Stable output current is obtained after interference line filters, rectifiers, filters, high-frequency transformers, high-frequency filters, mos tubes, control chips and drivers.

In order to achieve the above-mentioned object, the present invention also provides a plating fixture based on a power supply device, which includes a fixture body, a cover plate and the power supply device according to the preceding claim; the fixture body is provided with a semiconductor component. An adapted groove, wherein the conductive ring body in the power supply device is disposed on the lower surface of the semiconductor component; the cover plate is provided with an elastic cushion ring and a boss with an external dimension adapted to the groove ; When the cover plate presses on the upper surface of the semiconductor component, the two parts form a cavity after the boss falls into the groove, and the semiconductor component and the conductive ring body are placed in the cavity, and the jig A plurality of conductive copper hooks are also fixed side by side on the body, and each high-frequency switch rectifier is connected to an electrode of a corresponding conductive segment through a corresponding cable through a corresponding conductive copper hook.

The groove is provided with an annular groove for placing a conductive ring body therein.

Wherein, the boss is provided with an external thread, and the inner wall of the groove is provided with an internal thread adapted to the external thread. When the cover plate is rotated down through the internal and external threads, the cover plate is There is a linear relationship between the pressure and the downspin distance.

Compared with the prior art, the conductive ring provided by the present invention, the power supply device based on the same and the electroplating fixture based on the power supply device have the following beneficial effects: 1) The conductive ring is divided into multiple sections, and each section can independently conduct current. Control to ensure the consistency and uniformity of the overall current distribution density of the wafer or printed circuit board, and to ensure the quality of the surface plating layer; 2) the addition of a nickel plating layer and a silver plating layer on the traditional conductive ring body, thereby reducing the conductivity Impedance, and enhances the stability of its current transmission, thereby reducing the frequency of repairing and replacing the conductive ring body, reducing the maintenance cost; 3) current control of each segmented conductive ring body through a high-frequency switch rectifier, during power supply It can be adjusted in real time according to the current feedback, which makes it easier to ensure the consistency and uniformity of the current distribution density of the wafer or printed circuit board as a whole; 4) After the boss falls into the groove, the two form a cavity, and the semiconductor component and the conductive ring body are placed in the cavity. This structure makes the conductive method of the conductive ring body from the traditional point contact and line. The contact is changed into a surface contact, which greatly improves the uniformity and current density of the current distribution on the wafer or printed circuit board. Furthermore, there is a certain pressure between the wafer or printed circuit board and the conductive ring body, even if the plating solution oscillates. It will not cause poor contact. In addition, the elastic pad ring isolates the plating solution from the lower surface of the wafer or printed circuit board, avoiding the phenomenon of cross-erosion of chemicals during the plating process, thereby improving the wafer. Or printed circuit board plating quality.

1‧‧‧ Fixture body

2‧‧‧ wafer

3‧‧‧Conductive ring body

4‧‧‧ cover

5‧‧‧ elastic cushion ring

6‧‧‧High Frequency Switch Rectifier

7‧‧‧ Boss

8‧‧‧cable

9‧‧‧ conductive copper hook

10‧‧‧Anode plate

11‧‧‧ groove

31‧‧‧Conductive section

32‧‧‧ Disconnect

33‧‧‧electrode

34‧‧‧ support feet

FIG. 1 is a schematic structural diagram of a conductive ring in the present invention; FIG. 2 is a partially enlarged view of I in FIG. 1 in the present invention; FIG. 3 is a schematic diagram of a power supply device in the present invention; Schematic diagram of the structure of the electroplating jig; FIG. 5 is a schematic perspective view of the jig body in the electroplating jig of the present invention.

In order to express the present invention more clearly, the present invention is further described below with reference to the accompanying drawings.

Please refer to FIGS. 1-2. The conductive ring provided by the present invention includes a conductive ring body 3, which is distributed in a segmented structure and is composed of multiple conductive segments 31; between each adjacent two conductive segments The disconnection opening 32 is filled with insulating glue and separated by the insulating glue; The surface of the body is wrapped with an insulating glue layer; and the conductive ring body is provided with at least one electrode 33 and at least one support leg 34.

In this embodiment, a nickel plating layer and a silver plating layer are sequentially disposed on the outer surface of the conductive ring body 31 from the inside to the outside, and the silver plating layer is disposed between the nickel plating layer and the insulating rubber layer.

In this embodiment, the thickness of the nickel plating layer is 3 to 8 μm, and the thickness of the silver plating layer is 15 to 30 μm; and the size of the cutout is 3 to 5 mm. The conductive ring body is made of stainless steel, and each of the conductive segments is provided with a plurality of the supporting legs and is evenly distributed along its circumferential direction. The conductive ring adopting the above technical solution is evenly divided into multiple segments, and each segment can independently perform current control, thereby ensuring the consistency and uniformity of the overall current distribution density of the wafer or printed circuit board, and ensuring the quality of its surface plating layer. .

As a further optimization of the conductive ring body 3, in order to improve the corrosion resistance of the conductive ring body 3, it can be made of stainless steel, and its surface is plated with a nickel plating layer and a silver plating layer, which are sequentially arranged from the inside to the outside, so that The conductive impedance is reduced, and the stability of the current transmission is enhanced, thereby reducing the frequency of repairing and replacing the conductive ring body 3, and reducing the repair cost. The thickness of the nickel plating layer is preferably 3 to 8 μm; the thickness of the silver plating layer is preferably 15 to 30 μm.

Please refer to FIG. 3 further, the present invention further provides a power supply device based on a conductive ring, which includes a plurality of high-frequency switching rectifiers 6 and the above-mentioned conductive rings, the number of the high-frequency switching rectifiers is the same as the number of conductive segments 31 of the conductive ring; And each high-frequency switching rectifier is in communication with a corresponding conductive segment. The positive electrode of each high-frequency switching rectifier is connected to the anode plate 10; the conductive ring is connected to the semiconductor components, and the plating solution is between the anode plate and the semiconductor components; the high-frequency switching rectifier provides voltage and current to the entire circuit. Under the action of the voltage potential of the high-frequency switching rectifier, the anode plate dissolves metal cations into the plating solution, and the metal ions in the plating solution move toward the semiconductor components with the direction of the power line. Finally, the metal cations are precipitated on the semiconductor components and formed. Metal simple substance, both complete the plating process. The semiconductor components here are wafers.

Each high-frequency switching rectifier includes an anti-electromagnetic interference line filter, a rectifier, a filter, a high-frequency transformer, a high-frequency filter, a mos tube, a control chip, and a driver connected in sequence; the AC power grid passes through the anti-electromagnetic interference line in order. Filters, rectifiers, filters, high-frequency transformers, high-frequency filters, mos tubes, control chips and drivers get stable output current. FIG. 3 shows a schematic diagram of the electroplating power supply device in the present invention. The four segments of the conductive ring body 3 are independently connected to four high-frequency switch rectifiers, respectively. The high-frequency switching rectifier directly rectifies and filters the AC power grid through an electromagnetic interference-prevention line filter. The converter converts the DC voltage into a high-frequency square wave of tens or hundreds of kHz, and then isolates and steps down the voltage through a high-frequency transformer. Outputs DC voltage after high-frequency filtering. After sampling, comparing, amplifying, controlling, and driving the circuit, the duty cycle of the power tube in the converter is controlled to obtain a stable output current. The high frequency switching rectifier has a constant current voltage limiting mode. When the plating process parameters (such as part area, temperature, concentration, and pH) change, the output current is automatically constant at the set value without changing, ensuring the consistency and uniformity of the overall current distribution density of the wafer, and ensuring its surface plating layer. quality. The high-frequency switching rectifier here has a current of 10A and a voltage of 15V; it is currently available on the market.

Please refer to FIGS. 4-5. The present invention also provides a plating fixture based on a power supply device, which includes a fixture body 1, a cover plate 4, and the power supply device; the fixture body is provided with a component suitable for semiconductor components. A groove 11 is provided, and the conductive ring body in the power supply device is disposed on the lower surface of the semiconductor component; the cover plate 4 is provided with an elastic cushion ring 5 and an outer dimension matching the groove Boss 7; the semiconductor component is a wafer or a printed circuit board, and the semiconductor component shown in the figure is wafer 2. When the cover plate presses the upper surface of the semiconductor component, the boss falls into the groove The latter two form a cavity, the semiconductor component and the conductive ring body are placed in the cavity, a plurality of conductive copper hooks are fixed side by side on the fixture body, and each high-frequency switch rectifier passes a corresponding conductive copper hook 9 Connect to the electrode of the corresponding conductive segment through a cable. Open the wire on the fixture body Correspondingly, a cable 8 connected to each section of the conductive ring body is arranged in the line slot. In consideration of the rationality of the current product layout, the conductive ring body is divided into 4 sections. Accordingly, the high-frequency switch The number of rectifiers is set to 4, of course, the conductive ring body can also be divided into 6 segments, 8 segments, etc. according to the actual situation.

In this way, the conductive manner of the conductive ring body 3 is changed from the traditional point contact and line contact to the surface contact, which greatly improves the uniformity and current density of the current distribution on the wafer 2. Furthermore, the wafer 2 and the conductive There is a certain pressure between the ring bodies 3, and even if the electroplating solution oscillates, it will not cause poor contact. In addition, under the action of the elastic cushion ring 5, the electroplating solution is isolated from the lower surface of the wafer 2 to avoid the plating process. The phenomenon of chemical cross-corrosion occurs in the medium, thereby improving the plating quality of the wafer 2.

In this embodiment, an annular groove for placing a conductive ring body is provided in the groove. In order to avoid the entanglement of the conductive ring body 3 during the long-term use of the electroplating jig, a ring groove may be provided in the groove for placing the conductive ring body 3, and its shape is adapted to the conductive ring body 3, thereby The problem that the conductive ring body 3 is turned over during the process of pressing the wafer 2 is avoided, thereby causing the problem of uneven current distribution on the surface of the wafer 2.

In this embodiment, the boss is provided with an external thread, and the inner wall of the groove is provided with an internal thread adapted to the external thread. When the cover plate is rotated down through the internal and external threads, the cover plate The pressure of semiconductor components is linearly related to the downspin distance. When the cover plate 4 is screwed down by the thread, the pressure of the cover plate 4 on the wafer 2 and the downward rotation distance are linear, which is convenient for adjusting the pressure. In addition, the conductive ring body 3 in contact with the wafer 2 does not exist. The problem of uneven force ensures the conductivity of each region of the wafer 2 is uniform, and the seal around the wafer 2 is also consistent. In this embodiment, only the wafer is used as an example for description, and the content can also be applied to a printed circuit board.

The above disclosure is only a few specific embodiments of the present invention, but the present invention is not limited thereto, and any change that can be thought by those skilled in the art should fall into the protection scope of the present invention.

Claims (9)

A conductive ring is characterized in that it comprises a conductive ring body which is distributed in a segmented structure and is composed of a plurality of conductive segments; the opening between each adjacent two conductive segments is filled with insulating glue and passed through The insulating glue is separated; the surface of the conductive ring body is covered with an insulating glue layer; and the conductive ring body is provided with at least one electrode and at least one supporting leg. The conductive ring according to claim 1, wherein the outer surface of the conductive ring body is sequentially provided with a nickel plating layer and a silver plating layer, and the silver plating layer is disposed between the nickel plating layer and the insulating rubber layer. between. The conductive ring according to claim 2, wherein the thickness of the nickel plating layer is 3 to 8 μm, and the thickness of the silver plating layer is 15 to 30 μm; and the size of the cutout is 3 to 5 mm. The conductive ring according to claim 1, wherein the conductive ring body is made of stainless steel, and each of the conductive segments is provided with a plurality of the support legs and is evenly distributed along its circumferential direction. A power supply device based on a conductive ring, comprising: a plurality of high-frequency switching rectifiers and the conductive ring according to any one of claims 1 to 4, the number of the high-frequency switching rectifiers and a conductive segment of the conductive ring The number is the same; and the negative electrode of each high-frequency switching rectifier is connected to the corresponding conductive segment; the positive electrode of each high-frequency switching rectifier is connected to the anode plate; the conductive ring is connected to the semiconductor component, and the anode plate and the semiconductor component The electroplating solution is provided between the high-frequency switching rectifiers. The high-frequency switching rectifiers provide voltage and current to the entire circuit. Under the action of the voltage potential of the high-frequency switching rectifiers, the anode plate dissolves metal cations into the electroplating solution. The direction moves toward the semiconductor component, and finally metal cations are precipitated on the semiconductor component to form a metal element, which completes the electroplating process. The conductive ring-based power supply device according to claim 5, wherein each high-frequency switching rectifier includes an anti-electromagnetic interference line filter, a rectifier, a filter, a high-frequency transformer, a high-frequency filter, a mos tube, A control chip and a driver; the AC power grid obtains a stable output current after passing through an electromagnetic interference prevention line filter, a rectifier, a filter, a high-frequency transformer, a high-frequency filter, a mos tube, a control chip, and a driver. An electroplating jig based on a power supply device, comprising: a jig body, a cover plate and the power supply device according to claim 5; the jig body is provided with a groove adapted to a semiconductor component, The conductive ring body in the power supply device is disposed on the lower surface of the semiconductor component; the cover plate is provided with an elastic backing ring and a boss with an external dimension matching the groove; the cover plate is opposite When the upper surface of the semiconductor component is compacted, the convex part falls into the groove to form a cavity. The semiconductor component and the conductive ring body are placed in the cavity. The fixture body is also fixed side by side. Multiple conductive copper hooks, and each high-frequency switch rectifier is connected to an electrode of a corresponding conductive segment through a corresponding cable through a corresponding conductive copper hook. The electroplating jig based on the power supply device according to claim 7, wherein the groove is provided with an annular groove for placing a conductive ring body. The electroplating fixture based on the power supply device according to claim 7, wherein the boss is provided with an external thread, and the inner wall of the groove is provided with an internal thread adapted to the external thread. 3. When the external thread is turned down, the pressure of the cover plate on the semiconductor components and the distance of the down-rotation have a linear relationship.