Preparation method of tubular niobium target for magnetron sputtering

Abstract

The invention discloses a preparation method of a tubular niobium target for magnetron sputtering. The method comprises the following steps of: forging a niobium casting ingot into a cylindrical niobium blank; drilling a through hole at the center of the cylindrical niobium blank to obtain a tubular niobium blank, and then uniformly coating anti-oxidization coatings on the surfaces of the inner and outer walls of the tubular niobium blank; extruding the tubular niobium blank coated with the anti-oxidization coatings to obtain a niobium tube blank; sequentially carrying out sand spraying, acid washing and machining on the niobium tube blank to obtain a semi-finished product of the tubular niobium target; and carrying out vacuum heat treatment on the semi-finished product of the tubular niobium target to obtain the tubular niobium target for the magnetron sputtering. The tubular niobium target prepared by the method disclosed by the invention has a good structure property; and crystal grains along the wall thickness direction of the target are uniform and can reach the grade of 4-6, the size of the crystal grains is not more than 100 mu m, and the re-crystallization rate of the grains is not less than 90%, so that the uniform consistency of a coating film in the magnetron sputtering is guaranteed.

Description

technical field [0001] The invention belongs to the technical field of sputtering target manufacture, and in particular relates to a method for preparing a tubular niobium target for magnetron sputtering. Background technique [0002] Before 2008, all magnetron sputtering used plate targets, that is, the targets were rectangular plates with a certain thickness in terms of shape. One of the biggest disadvantages of such a target is that the utilization rate of the material is only 25% to 30%. [0003] The use of tubular targets is of particular importance for the coating industry. By assembling a controllable magnet in a seamless tube (tubular target) of a certain size, the surface of the sputtering target has no dead angle, and the self-consumption process of the target surface is relatively uniform, and the material utilization rate can be increased to 70% % or even higher, even if the manufacturing cost of the tubular target itself increases, it will be more than one-thi...

AI Technical Summary

Problems solved by technology

Usually, the niobium tube target prepared by the casting method has coarse grains, low tube target strength, complex subsequent processing procedures and low film formation rate; although the niobium plate coiled tube welding process is simple and the yield is high, this method is due to the weld seam Existence, resulting in uneven structure of the niobium tube target, will have a serious impact on the uniformity of the coating; the centrifugal casting method is a near-forming technology, the method is simple, and there is less follow-up processing, but it has high requirements for equipment, and it is difficult to produce large-size niobium tube targets and process them. Large-scale industrial production; it is difficult to prepare a thick-walled tube target by electroplating or thermal spraying niobium metal on the support tube, and the wall thickness of the tube target is an important factor to improve the utilization rate of the target

[0005] The invention patent with the publication number CN 102489951A published on June 13, 2012 provides a method for preparing a niobium tubular target for sputtering. The purpose is to provide anti-oxidation protection for the niobium tube billet, but during the extrusion process, the sheath is likely to cause uneven deformation and clogging within the range of about 400mm at the outlet end of the tube billet, which has a serious impact on the outer diameter of the tubular target in this section. Affected or even scrapped; at the same time, the sheath material is difficult to remove in the subsequent process, which seriously affects the purity of niobium processing residues and generates waste

In addition, this method first performs vacuum heat treatment on the extruded niobium tube target, and then performs mechanical processing. After vacuum heat treatment, the strength and hardness of pure metal niobium decrease, and it is difficult to ensure the dimensional accuracy and surface finish of the tubular niobium target during machining.