US20080283394A1

US20080283394A1 - Magnetron sputtering target

Info

Publication number: US20080283394A1
Application number: US12/098,167
Authority: US
Inventors: Yunxin ZHANG
Original assignee: Beijing BOE Optoelectronics Technology Co Ltd
Current assignee: Beijing BOE Optoelectronics Technology Co Ltd
Priority date: 2007-05-15
Filing date: 2008-04-04
Publication date: 2008-11-20
Also published as: CN201068469Y

Abstract

A magnetron sputtering target, which can improve utilization rate and service life of target materials and can be used in a magnetron sputtering technology, is provided. The magnetron sputtering target comprises a target material, a target back plate, an insulating pad, a target cathode frame, one or more leading pole piece adjustment pads, and one or more juxtaposed magnets, which are stacked in order. The leading pole piece adjustment pad is disposed between the insulating pad and the magnet.

Description

FIELD OF THE INVENTION

The present invention relates to a magnetron sputtering target.

BACKGROUND OF THE INVENTION

A magnetron sputtering technology has been widely used in many fields, such as surface decoration of materials, surface modification of materials, and manufacturing of optical devices and electronic devices. Magnetron sputtering targets can be divided into classes of a plain magnetron sputtering target and a column magnetron sputtering target by structure, and can also be divided into classes of a balancing target and a non-balancing target by distribution of the magnetic field. Material used in a plain magnetron sputtering target is advantageous because of simple processing and convenient installation, and therefore can be used for mass production of products to be coated. Generally, the sputtering target material, such as titanium (Ti), silver (Ag) and platinum (Pt), is expensive, which increases the manufacturing cost.
The conventional process of the magnetron sputtering for coating is shown in FIG. 1. Under a vacuum condition, when a target material 5 is applied with a negative potential and the work piece to be coated is applied with a positive potential, an electric field 1 (shown by {right arrow over (E)}) is established in the vacuum chamber where the target material 5 is located. Then, a process carrier gas (Ar) is introduced into the vacuum chamber and discharging phenomenon occurs due to the positive potential and the negative potential under a certain pressure and temperature. Electrons (e) move along a circular orbit and impinge the molecules of the process carrier gas (Ar), thus producing plasma discharging. Meanwhile, the magnet on the magnetron sputtering target generates a magnetic field 2, which is applied to the electric field 1 and thus enhances the vapor deposition and the plasma discharging. The positive ions in the plasma are attracted to the cathode and impinge onto the surface of the cathode as a result of action of the electric field and the magnetic field, such that the atoms of the cathode target material is sputtered out and attached to the surface of the anode. The cathode mask shield is used for blocking the non-sputtering area of the cathode from plasma discharging, so that the ions flying to the cathode impact target material 5 and portions of the cathode target material will be sputtered out and deposited, forming a thin film of the cathode target material on the surface of the anode (the work piece to be coated), and thus the work piece on the anode is coated.
However, the uniformity of the plasma on the surface of the cathode will be affected by an end effect at the turning of the orbit of the electrons in the plasma. At two ends of the orbit of the electrons in the plasma, plasma is intensive, sputtering effect is good, and more sputtering target materials are etched. While in the middle portion of the sputtering target material, less target material is etched, producing a phenomenon that etching in the middle portion of the target material and that in the ends of the target material are not uniform, thus shortening the service life of the target. The profile of the etched target is shown in FIG. 2 in a cross-section view.

SUMMARY OF THE INVENTION

An object of the present invention is to provide a magnetron sputtering target solving the problems of the uniformity of etching, low utilization rate of target materials and short service life of the sputtering target materials in the conventional magnetron sputtering technology.
In order to achieve the above objects, an embodiment of the present invention provides a plain magnetron sputtering target, comprising a target material, a target back plate, an insulating pad, a target cathode frame, one or more leading pole piece adjustment pads, and one or more juxtaposed magnets, which are stacked in order. The leading pole piece adjustment pad is disposed between the insulating pad and the magnet.
Preferably, the leading pole piece adjustment pads may be disposed between the insulating pad and the magnet, between the insulating pad and the target cathode frame, or at the both positions.
Preferably, when the leading pole piece adjustment pad is disposed between the target cathode frame and the magnet, the leading pole piece adjustment pad may be fixed on the upper surface of the magnet, or on the surface of the target cathode frame opposite to the magnet, or leading pole piece adjustment pads are disposed on the above two surfaces, and they can be disposed opposite to each other or at least partially overlap with each other.
Preferably, when the leading pole piece adjustment pad is disposed between the insulating pad and the target cathode frame, the leading pole piece adjustment pad may be fixed on the target cathode frame, or on the insulating pad, or leading pole piece adjustment pads are disposed on the two surfaces.
The embodiments of the present invention reduces the etching rate difference between the ends and the middle portion of the target materials by adjusting the uniformity of the magnetic field of the magnetron sputtering target and adjusting the uniformity of the plasma on the surface of the ends of the target materials, thereby shortening the etching difference between the ends and the middle portion of the target material and prolonging the service life of the target materials. The magnetron sputtering target further can be used in a multi-target magnetron sputtering machine for manufacturing a thin film transistor liquid crystal display (TFT-LCD).
Further scope of applicability of the present invention will become apparent from the detailed description given hereinafter. However, it should be understood that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from the following detailed description.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will become more fully understood from the detailed description given hereinafter and the accompanying drawings which are given by way of illustration only, and thus are not limitative of the present invention and wherein:

FIG. 1 is a schematic view illustrating the track of the electrons on the surface of the magnetron sputtering target material and the plasma;

FIG. 2 is a cross-section schematic view illustrating a profile of a target material in etching state in a conventional target;

FIG. 3 is a schematic view illustrating a magnetron sputtering target according to a first embodiment of the present invention;

FIG. 4 is a schematic view illustrating a magnetron sputtering target according to a second embodiment of the present invention;

FIG. 5 is a schematic view illustrating a magnetron sputtering target according to a third embodiment of the present invention;

FIG. 6 is a schematic view illustrating a magnetron sputtering target according to a fourth embodiment of the present invention;

FIG. 7 is a schematic view illustrating a magnetron sputtering target according to a fifth embodiment of the present invention;

FIG. 8 is a schematic view illustrating a distribution of leading pole piece adjustment pads on a target cathode frame according to the fifth embodiment of the present invention; and

FIG. 9 is a cross-section schematic view illustrating a profile of a target material in etching state in the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The following is a detailed description of the technical solution of the present invention in conjunction with the accompanying drawings, which are given in a illustrative purpose but not in a limitative purpose.

First Embodiment

As shown in FIG. 3, according to the first embodiment of the present invention, a target material 5 and a target back plate 6 are stacked together; the target back plate 6 and a insulating pad 7 are stacked together; a target cathode frame 8 is used for carrying the target material 5, the target back plate 6 and the insulating pad 7 which are stacked in this order; a cathode mask shield 9 is disposed on the target cathode frame 8 and exposes at least a portion of the target material 5; one or more magnets 10 are juxtaposed disposed, connected to the target cathode frame 8 through a transmission shaft, and are movable within a certain range; one or more leading pole piece adjustment pads 11 are disposed between the target cathode frame 8 and the magnets 10 and fixed on the upper surface of the movable magnets. Herein, the leading pole piece adjustment pads 11 are disposed corresponding to the respective magnets 10.
The leading pole piece adjustment pads 11 are made of a metal material that is magnet conductor. Such leading pole piece adjustment pads 11 can be used to make the magnetic lines short and reduce the intensity of the magnetic lines going out of the surface of the target material. The pads 11 can be, for example, in a shape of a rectangle, a circle, a regular or irregular polygon, etc. in a plan view and may be a sheet in construction.

Second Embodiment

As shown in FIG. 4, the plain magnetron sputtering target according to this embodiment is generally similar with that according to embodiment 1, except that the leading pole piece adjustment pads 11 can also be fixed on the surface of the target cathode frame 8. Here the leading pole piece adjustment pads 11 are disposed corresponding to the respective magnets 10.

Third Embodiment

As shown in FIG. 5, the difference between this embodiment and the above embodiments lies in that the leading pole piece adjustment pads 11 are disposed between the insulating pad 7 and the target cathode frame 8, and can be fixed on the insulating pad 7 or the target cathode frame 8. Here, the leading pole piece adjustment pads 11 are disposed corresponding to the respective magnets 10.

Fourth Embodiment

In the above embodiments, the leading pole piece adjustment pads are disposed in one position, and it has been found by experiment that the effect of the leading magnetic piece adjustment pads can adjust the magnetic field generated by the magnet 10. In the present embodiment, as shown in FIG. 6, different from the above embodiments, the leading pole piece adjustment pads 11 are disposed between the target cathode frame 8 and the magnets 10, which are not only fixed on the upper surface of the movable magnets but also on the surface of the target cathode frame 8, and thus the leading pole piece adjustment pads 11 can be disposed opposite to each other or can be at least partially overlapped with each other. In the present embodiment, the effect of the leading pole piece adjustment pads in adjusting the uniformity of the magnetic field generated by the magnet 10 is more significant. Here the leading pole piece adjustment pads 11 are disposed corresponding to the respective magnets 10.

Fifth Embodiment

On the basis of embodiment 4, leading pole piece adjustment pads 11 are further added between the insulating pad 7 and the target cathode frame 8 in the present embodiment. As shown in FIG. 7, the added leading pole piece adjustment pads 11 produce more fine adjusting effect on the magnetic field, so that the magnetic field in the vacuum chamber where the target material 5 is located is more uniform, and thus the non-uniformity of the target material being etched is improved. The distribution of the leading pole piece adjustment pads 11 on the target cathode frame is shown in FIG. 8. Here the leading pole piece adjustment pads 11 are disposed corresponding to the respective magnets 10.
By adopting the device according to the above embodiments of the present invention, in the frame structure of the magnetron sputtering target, the uniformity of the magnetic field generated by the magnets 10 is changed and the sputtering rate of the target material 5 is controlled by disposing the leading pole piece adjustment pads 11 on the plain magnetron sputtering target, such that the target material 5 is etched uniformly, and the utilization rate of the target material is improved.
With experiments, the profile of the target material 5 in etching is shown in FIG. 9, it can be seen that the sputtering target material is consumed more uniformly, the phenomenon that a part of the target material is over-etched is avoided, and thus the service life of the sputtering target material is prolonged.
The invention being thus described, it will be obvious that the same may be varied in many ways. Such variations are not to be regarded as a departure from the spirit and scope of the invention, and all such modifications as would be obvious to those skilled in the art are intended to be included within the scope of the following claims.

Claims

1. A plain magnetron sputtering target, comprising a target material, a target back plate, an insulating pad, a target cathode frame, one or more leading pole piece adjustment pads, and one or more juxtaposed magnets, which are stacked in order,

wherein the leading pole piece adjustment pad is disposed between the insulating pad and the magnet.

2. The plain magnetron sputtering target according to claim 1, wherein the leading pole piece adjustment pad is disposed between the target cathode frame and the magnet.

3. The plain magnetron sputtering target according to claim 1, wherein the leading pole piece adjustment pad is fixed on an upper surface of the corresponding magnet.

4. The plain magnetron sputtering target according to claim 1, wherein the leading pole piece adjustment pad is fixed on a surface of the target cathode frame opposite to the magnet.

5. The plain magnetron sputtering target according to claim 4, wherein the leading pole piece adjustment pad is further fixed on an upper surface of the magnet.

6. The plain magnetron sputtering target according to claim 1, wherein the leading pole piece adjustment pad is disposed between the insulating pad and the target cathode frame.

7. The plain magnetron sputtering target according to claim 6, wherein the leading pole piece adjustment pad is fixed on a surface of the target cathode frame opposite to the insulating pad.

8. The plain magnetron sputtering target according to claim 6, wherein the leading pole piece adjustment pad is fixed on a surface of the insulating pad opposite to the target cathode frame.

9. The plain magnetron sputtering target according to claim 8, wherein a leading pole piece adjustment pad is further fixed on a surface of the target cathode frame opposite to the insulating pad.

10. The plain magnetron sputtering target according to claim 1, wherein the leading pole piece adjustment pad is fixed on a surface of the target cathode frame opposite to the insulating pad.

11. The plain magnetron sputtering target according to claim 1, wherein the leading pole piece adjustment pad is fixed on a surface of the insulating pad opposite to the target cathode frame.

12. The plain magnetron sputtering target according to claim 1, further comprising a cathode mask shield that is provided on the target cathode frame and at least exposing a portion of the target material.