Nickel-plating solution for preparing semiconductor silicon wafers

Abstract

The invention discloses a nickel-plating solution for preparing semiconductor silicon wafers. The nickel-plating solution comprises the following components: soluble nickel salt, a reducer, a pH value regulator composed of hydrochloric acid and ammonia water, compound complex agents and deionized water, wherein the compound complex agents are selected from at least two of citric acid and soluble salt thereof, tartaric acid and soluble salt thereof, lactic acid and soluble salt thereof, malic acid and soluble salt thereof, butanedioic acid and soluble salt thereof, ethylenediamine tetraacetic acid and soluble salt thereof, hydroxyethylenediamine triacetic acid and soluble salt thereof; the pH value of the nickel-plating solution is 7.5-9.5. The pH value regulator composed of hydrochloric acid and ammonia water is added into the nickel-plating solution, so that the pH value in the nickel plating process remains stable; weak acids used as complex agents and the soluble salts thereof can be combined with the pH value regulator to form a buffer system, so that the pH value can be further regulated; at least two complex agents are used cooperatively, so that the nickel-plating solution is high in stability and moderate in nickel-plating rate.

Description

technical field [0001] The invention relates to the technical field of nickel plating solution compositions, in particular to a nickel plating solution for preparing semiconductor silicon wafers. Background technique [0002] The electroless nickel plating process is used for semiconductor components, and a layer of electrical contact material is covered on the surface of the components. This is a technology introduced from the chemical industry to solve the ohmic contact. Its essence is that the soluble nickel salt and the reducing agent component in the nickel plating solution undergo a redox reaction, and nickel ions obtain electrons provided by the reducing agent and are reduced to metal nickel and deposited on the surface of semiconductor components. [0003] The commonly used electroless nickel plating solution in the prior art is an alkaline nickel plating solution. CN102168258A discloses a kind of alkaline electroless nickel plating solution, the composition of this...

AI Technical Summary

Problems solved by technology

In actual use, it is found that the pH value has a great influence on the plating speed and the nickel plating solution system. The specific performance is: the pH value increases, the plating speed accelerates, but the increase is not very large, but the pH value is too high, and the high concentration of hydrogen Oxygen ions will weaken the comp