JPH039330Y2 - - Google Patents

Description

[Detailed Description of the Invention] Industrial Field of Application This invention relates to a semiconductor manufacturing device, and more particularly to a jet plating device for forming bump electrodes on a semiconductor wafer.

Conventional technology For example, a DHD diode has a structure in which a diode element having a bump electrode is sandwiched between two slag leads via the electrodes and sealed with glass, and the bump electrode of the diode element is electrically connected to the slag lead. Ag is added to 50~ for the purpose of stabilizing contact etc.
It is formed by plating to a height of about 60 μm. Such bump electrode plating is performed on a semiconductor wafer on which a large number of diode elements are formed, and the plating methods are roughly divided into immersion method and jet method.

The immersion method is a method in which wax is applied to the non-plated surface of a semiconductor wafer, the semiconductor wafer is immersed together with a plating electrode plate in a plating solution, and a plating voltage is applied between the semiconductor wafer and the electrode plate to perform plating. However, this method requires the application of wax before plating and the removal of the wax applied to the semiconductor wafer after plating, so jet plating methods have recently become mainstream.

A conventional example of the above-mentioned jet plating device will be described below with reference to FIG. 2. Reference numeral 1 denotes a vertically installed plating cylinder, and a plurality of insulating support pins 2, 2, . . . protrude at equal intervals from the upper end surface of the opening. will be established. 3 is a cover surrounding the plating tube 1; 4 is a mesh-shaped lower electrode installed inside the plating tube 1; 5 is a semiconductor wafer (hereinafter referred to as a wafer) held with the surface to be plated downward by support pins 2, 2, . . . , and 6 is an upper electrode that contacts the upper surface of the wafer 5. 7 is a plating liquid containing an Ag component that rises from the bottom of the plating tube 1 through the lower electrode 4 and jets from the center to the periphery of the lower surface of the wafer 5, overflowing the upper end of the opening of the plating tube 1 and covering it. The liquid flows down into the plating cylinder 1, is stored in the liquid storage tank 8, and is circulated through a route where it is supplied again to the lower part of the plating cylinder 1 by the pump 9.

For example, as shown in FIGS. 3 and 4, the wafer 5 has a large number of P-type anode type diode elements (hereinafter referred to as elements) 10, 10 arranged in a lattice pattern, in which 11 is a common back electrode, and 12 is a common back electrode. Insulating films formed on the surface, 13, 13... are insulating films 12
This window hole is selectively formed in the window hole 13, 13.
After first forming the Au vapor deposited films 14, 14... on the above plating device, the Ag bump electrodes 15,
15... are formed in the following manner.

That is, as shown in FIG. 2, the wafer 5 is placed on the support pins 2, 2, . . . of the plating tube 1 with the back electrode 11 facing upward.
The top electrode 11 is pressed with the top electrode 6 to make electrical contact. In this state, when the plating liquid 7 is jetted out from the plating cylinder 1 and a positive plating voltage is applied to the lower electrode 4 and a negative plating voltage is applied to the upper electrode 6, a forward plating current flows from the plating liquid 7 to the wafer 5, and the plating liquid 7
Au vapor deposited film 1 whose Ag component is on the bottom surface of wafer 5
4, 14... are plated on the bump electrodes 15, 1
5... is formed.

Problems to be Solved by the Invention Incidentally, according to the jet plating apparatus described above, the plating liquid 7 is applied by applying a plating voltage between the upper and lower electrodes 4 and 6 while jetting the plating liquid 7 onto the surface to be plated of the wafer 5. Ag components are plated on the Au vapor deposited films 14, 14, . . . on the surface to be plated of the wafer 5, to form bump electrodes 15, 15, . However, when the plating liquid is jetted onto the surface of the wafer 5 to be plated, since the surface of the wafer 5 to be plated is dry and does not mix well with the plating liquid 7, the window holes 13, 13, etc. on the surface of the wafer 5 to be plated are Air accumulates and forms bubbles, and these bubbles sometimes cause bump electrodes not to be formed or bump electrodes with insufficient height to be formed, resulting in poor yields in semiconductor manufacturing.

Therefore, in order to solve the above-mentioned conventional problems, this idea was developed by pre-wetting the surface of the wafer to be plated to improve the compatibility with the plating solution and to prevent air bubbles on the surface of the wafer to be plated. The purpose is to prevent this occurrence and improve the yield of semiconductor manufacturing.

Means for solving the problem The structure of this invention to achieve the above purpose is as follows:
A plating cylinder that holds a semiconductor wafer with the surface to be plated facing down, an upper electrode that contacts the top surface of the semiconductor wafer on the plating cylinder, and a plating liquid that rises inside the plating cylinder and is disposed in the plating liquid that flows onto the bottom surface of the semiconductor wafer. The present invention is a jet plating device which is equipped with a lower electrode, and which applies a plating voltage between the upper and lower electrodes while jetting a plating liquid onto the surface to be plated of a semiconductor wafer to form bump electrodes partially on the semiconductor wafer. A prewetting nozzle for spraying moisture onto the surface of the semiconductor wafer to be plated is disposed within the plating cylinder.

Function: According to the above-described method, the surface of the semiconductor wafer to be plated is pre-wetted by spraying moisture from the prewetting nozzle, thereby improving the compatibility between the surface of the semiconductor wafer and the plating solution.

Embodiment An embodiment of this invention will be described below with reference to FIG. Note that the same reference numerals as in FIG. 2 indicate the same parts, and the explanation thereof will be omitted. A feature of this embodiment is that a prewetting nozzle 16 is installed inside the plating cylinder 1. This pre-wetting nozzle 16 uses a pump 17 to spray the plating liquid 7 from the liquid storage tank 8 into a conical shape, and plating the lower surface of the wafer 5 positioned and mounted on the support pins 2, 2... of the plating cylinder 1. It is arranged so that the liquid 7 is sprayed.

In the above configuration, first, the wafer 5 is placed with the back electrode 11 facing upward, and the support pins 2, 2, . . .
The top electrode 11 is pressed with the top electrode 6 to make electrical contact. In this state, open the valve 18 to return the plating liquid 7 in the plating cylinder 1 to the liquid storage tank 8, so that the liquid level reaches the prewetting nozzle 1.
When the temperature drops below the nozzle end of No. 6, the valve 18 is closed. Thereafter, the plating liquid 7 in the liquid storage tank 8 is sprayed by the prewetting nozzle 16 to wet the lower surface of the wafer 5. By making the bottom surface of the wafer 5 wet in this way, when the plating liquid 7 is jetted onto the bottom surface of the wafer 5, the bottom surface of the wafer 5 and the plating liquid 7 become more compatible, and this prevents air bubbles from being generated on the bottom surface of the wafer 5. It disappears. After that, if plating is performed in the same manner as before, a predetermined bump electrode 1 will be formed on the bottom surface of the wafer 5.
5, 15... are formed.

Effects of the invention According to this invention, in a device that performs plating while jetting plating liquid onto the surface of a wafer, the surface of the wafer to be plated is wetted in advance. When the liquid is jetted, the surface of the wafer to be plated and the plating liquid become better compatible, and the generation of bubbles on the surface of the wafer to be plated can be prevented.This improves the yield of semiconductor manufacturing and has great practical effects. A semiconductor manufacturing apparatus can be provided.

[Brief explanation of the drawing]

FIG. 1 is a sectional side view of the main part of a semiconductor manufacturing apparatus according to an embodiment of the present invention, FIG. 2 is a sectional side view of the main part of a conventional bump electrode plating apparatus, and FIGS. 3 and 4 are plated parts. Plan view of semiconductor wafer and -
It is a line enlarged sectional view. 1... Plating tube, 4... Lower electrode, 5... Semiconductor wafer, 6... Upper electrode, 7... Plating liquid,
15...Bump electrode, 16...Prewetting nozzle.

Claims (1)

[Scope of utility model registration request] A plating cylinder that holds a semiconductor wafer with the surface to be plated facing down, an upper electrode that contacts the top surface of the semiconductor wafer on the plating cylinder, and a plating liquid that rises inside the plating cylinder and is disposed in the plating liquid that flows onto the bottom surface of the semiconductor wafer. The present invention is a jet plating device which is equipped with a lower electrode, and which applies a plating voltage between the upper and lower electrodes while jetting a plating liquid onto the surface to be plated of a semiconductor wafer to form bump electrodes partially on the semiconductor wafer. A semiconductor manufacturing apparatus characterized in that a prewetting nozzle for spraying moisture onto a surface to be plated of a semiconductor wafer is disposed in the plating cylinder.