Preparation method of fine crystal molybdenum tantalum alloy sputtering target material. The invention includes the following steps :(1) molybdenum powder and tantalum powder are pretreated and screened respectively, and then mixed by ball milling to get molybdenum and tantalum mixed powder; (2) Use the powder feeder to make the molybdenum and tantalum mixed powder fall into the forming cavity of the cold isostatic pressing mold for cold isostatic pressing treatment; (3) demoulding, take out a sequence of pressing billet, put a sequence of pressing billet in the furnace body for sintering; (4) after the body is placed in the leveling die for leveling, the body is placed in the shaping die for shaping; (5) After surface treatment, hot isostatic pressing is carried out to obtain two-sequence green body; (6) rolling along the longitudinal direction of the two-sequence billet body at a certain temperature, when the two-sequence billet body has a certain amount of deformation, rolling along the transverse direction of the two-sequence billet body at a certain temperature; (7) The two-sequence blank body is machined to make its shape reach the target shape size, and connected with the backplane to make molybdenum tantalum alloy target material. The invention uses molybdenum powder and tantalum powder to treat, but without vacuum pretreatment, can not guarantee the purity of the powder. In addition, when cold isostatic pressing is carried out without the protection of different gas segments, the impurity content of the powder will be increased. In addition, the cost of preparing molybdenum tantalum alloy target by hot isostatic pressing is high, and the size of the product is limited by hot isostatic pressing equipment. Finally, the invention patent does not conduct vacuum heat treatment on the pressed blank body, which cannot reduce the content of hydrogen impurities and is prone to hydrogen embrittlements, which will affect the machining performance of molybdenum tantalum alloy.
The target material of molybdenum tantalum alloy is prepared by powder metallurgy, which has no pollution, less waste of resources, less cost and lower cost. The invention prevents hydrogen absorption embrittlement in the preparation process of molybdenum tantalum alloy, improves the processing performance of target material, prepares high density molybdenum tantalum alloy sputtering target material, ensures the purity of molybdenum tantalum alloy, and finally prepares high density molybdenum tantalum alloy target material with uniform fine grain. The mos-tantalum sputtering target prepared by the invention has good compactness, the relative density is more than 97%, the internal defect is less than 0.5mm, and the target surface is smooth and flat, which meets the technical requirements of mos-tantalum sputtering target for flat display device, and has excellent comprehensive performance.
