Preparation method of large-size molybdenum target material

Abstract

The invention belongs to the field of advanced metal material preparation research, and relates to a preparation method of a large-size molybdenum target material. The method comprises the following steps: by taking ammonium molybdate as a raw material, firstly carrying out ammonia dissolution and cation exchange treatment, then carrying out evaporative crystallization, and then carrying out hydrogen reduction to obtain high-purity molybdenum powder; the obtained high-purity molybdenum powder is subjected to cold isostatic pressing and hydrogen sintering, and a high-purity molybdenum plate blank is obtained; the obtained high-purity molybdenum plate blank is subjected to pre-forging cogging in a one-fire one-pass machining mode, a pre-forged blank is obtained, then a one-fire two-pass machining mode is adopted for multi-pass cross rolling, and a rolled plate blank is obtained; and the obtained rolled plate blank is subjected to surface chemical corrosion, then the corroded plate blank is subjected to homogenizing annealing treatment, and finally the large-size molybdenum target material is obtained. The target effects achieved by the preparation method are targeted purification, the crystal grains of the high-purity target material finished product are fine, the uniformity of the crystal grains in the thickness direction of the target material is good, and the orientation distribution of the crystal grains is uniform.

Description

technical field [0001] The invention belongs to the research field of advanced metal material preparation, and relates to a preparation method of a large-sized molybdenum target material. Background technique [0002] Molybdenum has a high melting point, good electrical and thermal conductivity, small specific resistance and film stress, and a very small thermal expansion coefficient. It can be processed as a target for application in the flat display industry. Large-scale high-purity and high-density molybdenum targets are used for gate and source / drain electrodes in TFT-CD / AMOLED manufacturing. With the continuous development of the panel toward the direction of large-scale and high-precision, the size of the molybdenum target used is getting larger and larger. For example, the width of the 8th generation linear molybdenum target for flat display is 200-300mm, and the length reaches 2700mm. With the successive start and production of the 6th, 7th and even 10th generation...

AI Technical Summary

Problems solved by technology

However, for high-purity molybdenum plates, when the purity is greater than 5N, due to the lack of dragging effects of impurities on dislocations and grain boundaries, it is particularly difficult to control the microstructure uniformity during plastic deformation and recrystallization.

It is mainly reflected in the problem that the texture gradient along the thickness direction of the plate and the strong anisotropy caused by the related plastic deformation are prone to occur during the hot rolling process, resulting in the non-uniform growth of the grains of the plate in the later stage of recrystallization treatment, which seriously deteriorates the Uniformity and service stability of high-purity molybdenum target throughout the sputtering life cycle

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