CN115323470B

CN115323470B - Device for realizing electroplating of multiple wafers

Info

Publication number: CN115323470B
Application number: CN202211239595.7A
Authority: CN
Inventors: 王传智; 王海涛; 李洁; 王伟豪; 刘冠东
Original assignee: Zhejiang Lab
Current assignee: Zhejiang Lab
Priority date: 2022-10-11
Filing date: 2022-10-11
Publication date: 2023-03-10
Anticipated expiration: 2042-10-11
Also published as: CN115323470A

Abstract

The invention relates to the field of wafer packaging, in particular to a device for realizing electroplating of multiple wafers. The invention realizes the simultaneous electroplating of a plurality of wafers by utilizing the layered structure of the wafer base, thereby saving the electroplating time and effectively avoiding the pollution and waste of electroplating solution; the annular electrode array is utilized to realize electroplating deposition, so that the wafer can be stabilized, the electroplating quality can be ensured, and the uniformity of the surface of the electroplated wafer is improved; by utilizing the stability of the wafer base, an electroplating method different from the traditional method can be implemented, the surface of the wafer is kept in a horizontal state, and electroplating solution and cost can be effectively saved aiming at large-size wafer electroplating.

Description

Device for realizing electroplating of multiple wafers

Technical Field

The invention relates to the field of wafer packaging, in particular to a device for realizing electroplating of multiple wafers.

Background

At present, most electronic devices are packaged by wafers, and the silicon wafer packaging usually goes through the processes of etching, electroplating, thinning and the like. The electroplating refers to depositing a metal layer on the surface of the wafer or in a micro-etched through hole etched on the wafer. The electroplating principle is that through electroplating solution, a plated part is at the cathode, metal to be plated is at the anode, and through adding a direct current power supply, the anode loses electrons, and cations are obtained at the cathode and reduced into metal, so that deposition is realized. Most cathode devices employ a hanger on which a wafer is mounted, vertically in solution, opposite an anode. When multiple wafers are to be plated, the plating is generally performed one by one. The plating solution is exposed to the air environment for a long time and is easy to be polluted, which is also an important reason for influencing the plating quality. The traditional hanger is limited by the vertical placement height of the wafer when the large-size wafer is electroplated, a large amount of electroplating solution is needed to meet the size of the wafer, the electroplating solution is often expensive, and the use cost is very high especially for laboratory-level scientific research.

Disclosure of Invention

In order to solve the technical problems in the prior art, the invention provides a device for electroplating a plurality of wafers, which has the following specific technical scheme:

a device for realizing electroplating of multiple wafers comprises an electroplating bath, a wafer base which is arranged in the electroplating bath and is of a multilayer structure, an electrode structure which is matched with the wafer base and is arranged into a nested structure and is connected in parallel, and an anode metal strip corresponding to the position of a wafer.

Further, through the nonmetal telescopic rod of detachable interconnection between the upper and lower layer of multilayer structure's wafer base, specifically be telescopic rod both ends through the wafer base interconnection of tenon fourth of the twelve earthly branches structure with upper and lower layer, wafer base and telescopic rod are the teflon material.

Furthermore, a shallow groove matched with the size of the wafer is formed in the wafer base, the depth of the shallow groove is smaller than or equal to the thickness of the wafer, an annular groove embedded with an elastic ring is formed in the edge of the inner side of the shallow groove, the elastic ring is made of fluorine glue, and the embedded height of the elastic ring is slightly higher than the surface of the bottom of the shallow groove.

Furthermore, the edge groove wall of the shallow groove is provided with a concave groove, and the concave groove extends to the elastic ring.

Furthermore, nuts made of Teflon and clamping pieces with holes and connected with the nuts in a penetrating mode are symmetrically arranged on two sides of the wafer base.

Furthermore, each layer of electrodes of the electrode structure is connected to the total cathode line in parallel, the electrodes comprise conducting rings and electrode bars, and the electrode bars are equal in length and are connected to the conducting rings to form an electrode annular array.

Further, the conducting ring comprises a teflon insulating ring layer, an annular core is arranged in the teflon insulating ring layer, tenon-and-mortise holes with equal intervals are formed in the lower surface of the teflon insulating ring layer, the tenon-and-mortise holes are connected with the electrode rods in a tenon-and-mortise structure, the annular core is connected to the main cathode wire through a conducting wire, and a guide pipe is sleeved outside the conducting wire;

the electrode bar is internally provided with a metal core, the outside of the electrode bar is provided with a detachable Teflon insulating layer, and the surface of the metal core is ground and polished.

Furthermore, the electrode structure and the wafer base are in a nested structure, a layer of electrode is embedded in each layer of wafer base, an electrode jack is arranged on one side of the wafer base, and the guide pipe is embedded in the electrode jack.

Further, the wires and the connections thereof are specifically: the connected wires with redundant length are arranged between each layer of electrodes, are connected to the total cathode line in parallel and belong to the same metal material, and the wrapping material outside the wires is silica gel.

Further, the anode metal strip is L-shaped and is positioned opposite or partially opposite to the wafer.

Compared with the prior art, the invention has the following advantages: the invention realizes the simultaneous electroplating of a plurality of wafers by utilizing the layered structure of the wafer base, thereby saving the electroplating time and effectively avoiding the pollution and waste of electroplating solution; the annular electrode array is utilized to realize electroplating deposition, so that the wafer can be stabilized, the electroplating quality can be ensured, and the uniformity of the surface of the electroplated wafer is improved; by utilizing the stability of the wafer base, an electroplating method different from the traditional method can be implemented, the surface of the wafer is kept in a horizontal state, and electroplating solution and cost can be effectively saved aiming at large-size wafer electroplating.

Drawings

FIG. 1 is a schematic view of the overall structure of the apparatus of the present invention;

FIG. 2 is a side cross-sectional line schematic of FIG. 1;

FIG. 3 is a top schematic view of FIG. 2;

FIG. 4 is a schematic diagram of a multi-layered wafer pedestal and electrode structure in accordance with an embodiment of the present invention;

FIG. 5 is a schematic view of the anode metal strip structure of the present invention;

FIG. 6 is a schematic view of a multi-layered wafer pedestal according to an embodiment of the present invention;

FIG. 7 is a schematic view of the telescopic rod of the present invention;

FIG. 8 is a schematic view of the structure of the position of the nut 5 and the clip 6 with holes on the wafer base according to the present invention;

FIG. 9 is a schematic diagram of a single layer structure of a wafer pedestal according to the present invention;

FIG. 10 is a schematic diagram of the multi-layered wafer pedestal of the present invention;

FIG. 11 is a schematic top view of FIG. 10;

FIG. 12 is a schematic structural view of an electrode of the present invention;

FIG. 13 is a side view schematic of the structure of FIG. 12;

FIG. 14 is a schematic diagram of a conductive ring structure according to the present invention;

FIG. 15 is a schematic view of the electrode rod structure of the present invention;

in the figure: 1-wafer pedestal, 2-telescopic rod, 3-shallow groove, 4-sunken groove, 5-nut, 6-clamping piece, 7-elastic ring, 8-conductive ring, 8 a-teflon insulating ring layer, 8 b-annular core, 8 c-mortise and tenon hole, 9-electrode rod, 9 a-insulating layer, 9 b-metal core, 10-lead, 10 a-lead silica gel, 11-anode metal strip and 12-electroplating bath.

Detailed Description

In order to make the objects, technical solutions and technical effects of the present invention more apparent, the present invention is further described in detail below with reference to the accompanying drawings and embodiments of the specification.

As shown in fig. 1 to 5, an embodiment of the present invention discloses an apparatus for electroplating multiple wafers, which includes an electroplating bath 12, a wafer base 1 disposed in the electroplating bath 12 and configured as a multi-layer structure, an electrode structure disposed in parallel and configured as a nested structure in cooperation with the wafer base 1, and an anode metal strip 11 corresponding to a position of a wafer. Wherein, the wafer is placed on a wafer base 1; the anode metal strip 11 is in an L shape.

The wafer base 1 of multilayer structure is used for placing the multi-disc wafer simultaneously, interconnects through corrosion-resistant detachable nonmetal telescopic rod 2 between the wafer base 1 of upper and lower layer, specifically is that telescopic rod 2 both ends are through tenon fourth of the twelve earthly branches structure and wafer base 1 of upper and lower layer interconnect, as shown in figure 6 and figure 7, through the flexible of telescopic rod 2, can change the distance between electrode and the wafer, is convenient for get and put the wafer, wafer base 1 and telescopic rod 2 are the teflon material.

The two sides of the wafer base 1 are symmetrically provided with nuts 5 made of Teflon and clamping pieces 6 with holes, the clamping pieces 6 are connected with the nuts 5 in a penetrating mode, as shown in fig. 8, the tightness between the clamping pieces 6 and the wafer is adjusted through the nuts 5, the nuts 5 are rotated, the clamping pieces 6 can also rotate, and therefore the wafer is convenient to stabilize.

The wafer base 1 is provided with a shallow groove 3 matched with the size of the wafer and used for placing the wafer, the depth of the shallow groove 3 is smaller than or equal to the thickness of the wafer, the inner side edge of the shallow groove 3 is provided with an annular groove embedded with an elastic ring 7, as shown in fig. 9, the elastic ring 7 is made of fluorine glue, the embedded height is slightly higher than the bottom surface of the shallow groove 3, the purpose is to make the wafer and the bottom of the shallow groove 3 in soft contact, and the damage to the back and the side of the wafer is avoided. After the wafer is embedded, the height of the clamping piece 6 is controlled through the nut 5 made of Teflon material, and the wafer is fixed. The edge groove wall of the shallow groove 3 is further provided with a concave groove 4, the groove position of the concave groove 4 extends to the elastic ring 7, and as shown in fig. 10 and 11, the concave groove 4 is arranged to facilitate taking down the electroplated wafer without damaging the surface of the wafer.

As shown in fig. 12 and 13, the electrodes include a conductive ring 8 and an electrode bar 9, and the electrodes of each layer are connected to the total cathode line, so that mutual interference can be realized; the electrode rods 9 are equal in length and are connected to the conducting ring 8 to form an electrode annular array, on one hand, the wafer is further fixed, on the other hand, wafer electroplating contact points are added, electroplating uniformity is achieved, electroplating quality is improved, and the quantity of the electrode rods 9 can be controlled through disassembly, so that electroplating uniformity is controlled. As shown in fig. 14, the conducting ring 8 includes a teflon insulating ring layer 8a, an annular core 8b is disposed in the teflon insulating ring layer 8a, and equidistant mortise and tenon holes 8c are disposed on the lower surface of the teflon insulating ring layer 8a, the mortise and tenon holes 8c are connected to the electrode rods 9 by mortise and tenon structures, the annular core 8b is connected to the total cathode line through a wire 10, and a guide pipe is sleeved outside the wire.

The electrode structure and the wafer base 1 are of a nested structure, specifically, each layer of wafer base 1 is embedded with one layer of electrode, one side of the wafer base 1 is provided with an electrode jack, the guide pipe is embedded at the electrode jack, and then the electrode structure forms the nested structure through the embedding structure of the guide pipe and the electrode jack.

As shown in fig. 15, the electrode rod 9 has a metal core 9b inside and a corrosion-resistant detachable teflon insulating layer 9a outside, and the surface of the metal core 9b is ground and polished to achieve good contact with the wafer.

The lead 10 is specifically: the connected lead 10 with redundant length is arranged between each layer of electrodes, is connected to the total cathode line in parallel and belongs to the same metal material, and the material wrapped outside the lead 10 is silica gel 10a so as to be matched with the telescopic rod 2 to move up and down.

The annular array formed by the electrode rods 9 can realize that the electrode with equal distance can be contacted in each angle range of the surface of the wafer to be plated, and high-efficiency and high-quality electroplating can be realized; in addition, the annular array formed by the electrode rods 9 drives the wafer base 1 to move up and down through the extension of the telescopic rod 2, and the wafer to be plated can be further fixed.

When the electroplating device of the invention is used, the anode metal strip 11 is horizontally arranged in the electroplating bath 12 and is opposite to the wafer arranged on the wafer base 1, so that uniform electroplating can be realized. Moreover, the invention can be suitable for electroplating large-size wafers, and electroplating solution is less than that used in the traditional mode when the large-size wafers are electroplated, so that the electroplating solution is saved.

In addition, the anode metal strip 11 is designed into an L shape, as shown in fig. 5, the anode and the cathode to-be-plated wafer can be opposite or partially opposite, so that the electroplating process is accelerated, and the electroplating uniformity is improved.

The above description is only a preferred embodiment of the present invention, and is not intended to limit the present invention in any way. Although the foregoing has described the practice of the present invention in detail, it will be apparent to those skilled in the art that modifications may be made to the practice of the invention as described in the foregoing examples, or that certain features may be substituted in the practice of the invention. All changes, equivalents and modifications which come within the spirit and scope of the invention are desired to be protected.

Claims

1. The device for realizing electroplating of the multiple wafers is characterized by comprising an electroplating bath (12), a wafer base (1) which is arranged in the electroplating bath (12) and is of a multilayer structure, an electrode structure which is matched with the wafer base (1) and is arranged into a nested structure and is connected in parallel, and an anode metal strip (11) corresponding to the position of the wafer;

each layer of electrode of the electrode structure is connected to a total cathode line in parallel, the electrode comprises a conductive ring (8) and an electrode bar (9), the electrode bar (9) is equal in length and is connected to the conductive ring (8) to form an electrode annular array;

the upper layer and the lower layer of the wafer base (1) of the multilayer structure are interconnected through a detachable nonmetal telescopic rod (2), the two ends of the telescopic rod (2) are interconnected with the wafer base (1) of the upper layer and the lower layer through a mortise and tenon structure, and the wafer base (1) and the telescopic rod (2) are made of Teflon materials.

2. The device for electroplating multiple wafers according to claim 1, wherein the wafer pedestal (1) is provided with a shallow groove (3) matching the wafer size, the depth of the shallow groove (3) is less than or equal to the wafer thickness, the inner side edge of the shallow groove (3) is provided with an annular groove for embedding the elastic ring (7), the elastic ring (7) is made of fluorine glue, and the embedded height is slightly higher than the bottom surface of the shallow groove (3).

3. An apparatus for electroplating multiple wafers according to claim 2, wherein the edge groove wall of the shallow groove (3) is provided with a concave groove (4), and the concave groove (4) extends to the elastic ring (7).

4. A device for electroplating multiple wafers according to claim 1, wherein the wafer base (1) is symmetrically provided with a nut (5) made of teflon and a clamping piece (6) with a hole penetrating through the nut (5) at two sides.

5. The device for electroplating multiple wafers according to claim 1, wherein the conductive ring (8) comprises a teflon insulating ring layer (8 a), an annular core (8 b) is arranged in the teflon insulating ring layer (8 a), and equidistant mortise and tenon holes (8 c) are formed in the lower surface of the teflon insulating ring layer (8 a), the mortise and tenon holes (8 c) are connected with the electrode rods (9) in a mortise and tenon joint structure, the annular core (8 b) is connected to the total cathode line through a conducting wire (10), and a guide pipe is sleeved outside the conducting wire (10);

the electrode rod (9) is internally provided with a metal core (9 b), the outer part of the electrode rod is provided with a detachable Teflon material insulating layer (9 a), and the surface of the metal core (9 b) is ground and polished.

6. The device for electroplating multiple wafers according to claim 5, wherein the electrode structure and the wafer base (1) are in a nested structure, a layer of electrode is embedded in each layer of wafer base (1), one side of the wafer base (1) is provided with an electrode jack, and the conduit is embedded in the electrode jack.

7. An apparatus for electroplating a plurality of wafers according to claim 5, wherein the wires (10) and their connections are: and a redundant-length connected lead (10) is arranged between each layer of electrodes, is connected to the total cathode line in parallel and belongs to the same metal material, and the outside of the lead (10) is wrapped by silica gel (10 a).

8. An apparatus for electroplating a plurality of wafers according to claim 1 wherein the anode metal strip (11) is L-shaped and positioned opposite or partially opposite the wafers.