A preparation method of high-purity tantalum target material for electronic materials

Abstract

The invention relates to a method for preparing a high-purity tantalum target for electronic materials, which belongs to the field of powder metallurgy and semiconductor device manufacturing. The preparation method is to pulverize a high-purity tantalum block first, and then ball mill it to a particle size of 5-150 μm. Tantalum powder; after mixing the tantalum powder, install the mold, vibrate and compact; then put the mold into a high-temperature hot-press furnace, and press at 1500-1800°C; after sintering, cool to room temperature and release the furnace to obtain high-purity Green body of tantalum target, density 11.3‑14.5g / cm 3 . According to the requirements of the magnetron sputtering equipment, the green body is cut and processed, and the processed green body is welded to the corresponding back plate according to the user's requirements to obtain a high-purity tantalum target. The high-purity tantalum target prepared by the present invention can significantly reduce the technical difficulty of preparing the target by the traditional casting method, greatly improve the controllability of the process, and contribute to the improvement of the coating performance of later materials.

Description

technical field [0001] The invention relates to the fields of powder metallurgy and semiconductor device manufacturing, in particular to a method for preparing a high-purity tantalum target. Background technique [0002] Magnetron sputtering coating has many advantages such as high uniformity and strong controllability, and has gradually become one of the most critical processes in the production process of integrated circuits and semiconductor chips. The quality of the sputtering target determines the coating effect of magnetron sputtering and the performance of semiconductor devices, so it has become an indispensable key material in the semiconductor field, especially in the chip manufacturing industry. The quality of the film formed after target sputtering, such as film thickness and uniformity, will significantly affect the performance of products in the semiconductor industry, and the film thickness and uniformity are almost entirely dependent on the structure of the ta...

AI Technical Summary

Problems solved by technology

[0004] When electron beam melting is used, due to the complex process, the melting process of the target material requires extremely high equipment conditions, so the preparation cost is very high

At the same time, since tantalum is a high-temperature refractory metal with a melting point close to 3000°C, and the preparation environment is an ultra-high temperature environment, high-purity tantalum is not only easily oxidized, but also impurity elements in the environment such as crucible materials can easily enter the melt, resulting in high-purity tantalum Impurities are mixed in the preparation, which seriously affects the performance of later products

Subsequent processing of high-purity ingots requires repeated plastic processing and heat treatment to make products. Since tantalum crystals are body-centered cubic, and the (111) crystal plane is its close-packed plane, it will slip preferentially during shaping processing, resulting in final plastic Most of the grain orientation of the product after shape processing is mainly (111), thus forming the "intrinsic texture band" of tantalum, which will cause the target sputtering rate to be low and the film thickness uneven, which seriously affects the quality of the tantalum target. Sputtering performance

Images