Acidic etching solution, as well as preparation method and application thereof

Abstract

The invention relates to an acidic etching solution, as well as a preparation method and an application thereof. The acidic etching solution comprises 1-20% by weight of hydrofluoric acid, 20-60% by weight of nitric acid, 1-20% by weight of fluosilicic acid and the balance of water. The preparation method comprises the following steps of: with fluorine hydride gas or hydrofluoric acid, 70-98% by weight of nitric acid water solution and silicon or silicon dioxide as raw materials, mixing according to the mixture ratio to get the acidic etching solution. The acidic etching solution is used for etching silicon wafers, GaAs wafers, GaP wafers or InP wafer. The acidic etching solution disclosed by the invention is different from the traditional etching solution, acetic acid, phosphoric acid and the like, which can cause greater burden on an environment, are not required, peculiar smell can be avoided, and wastes can also be reduced.

Description

technical field [0001] The invention belongs to the field of etching solution and its preparation method and application, in particular to an acid etching solution and its preparation method and application. Background technique [0002] Semiconductor devices in electronic devices such as computers include semiconductor integrated circuits and optical semiconductors as control elements and memory elements. During the manufacturing process of these semiconductor devices, substrates such as silicon, GaAs, GaP, and InP need to be etched or metal thin films are laminated to form circuits. In particular, semiconductor devices using silicon wafers are the most widely used and the most used in the industry. During the manufacturing process of semiconductor devices, multiple surface treatments are required on the substrate before circuits are formed on the substrate. The etching process is extremely important in determining the state of the substrate. [0003] The traditional tec...

AI Technical Summary

Problems solved by technology

[0010] As mentioned above, in the 3-component etching solution composed of hydrofluoric acid, nitric acid, acetic acid (or phosphoric acid), in addition to the problem that the etching rate is difficult to control during the etching process, the decline in etching performance and the instability of the etching process are also problems.

In addition, the etching solution contains acetic acid and phosphoric acid, and there is also the problem of bad smell, which makes it difficult to dispose of the waste solution

It is difficult to recycle waste liquid after use, which has become a big problem in the industry

[0011] On the other hand, as described above, etching solutions containing fluorosilicate components have not yet achieved good etching performance