Etching solution for use in wet etching of bismuth-based thin films

Abstract

Aiming at the technical problem that aqueous solution of HF, serving as etching solution, cannot etch a bismuth-based thin film material, nor ensure the accuracy of patterns, the invention provides etching solution for use in the wet etching of bismuth-based thin films, belongs to the technical field of materials and relates to micro machining technology, in particular to etching solution for use in a photoetching process. The etching solution is mixed solution comprising HF serving as an etching agent, NH4F serving as a complexing agent and H2O serving as a diluting agent in a molar ratio of 1: (0.5-1.5): (1.26-5.5). To enhance the etching effect of the etching solution on the bismuth-based thin film material and increase etching speed, HNO3 serving as an assistant can be added into the etching solution, wherein the ratio of the HF to the NH4F to the HNO3 to the H2O is 1: (0.5-1.5): (0.36-1.6): (1.26-5.5). The wet etching of the bismuth-based thin film material by the etching solution has the advantages of clean etched surface, clear patterns, high precision and no residual precipitate. After the HNO3 assistant is added, the speed of the wet etching of the bismuth-based thin films is increased, and the etching process and the pattern precision can be controlled effectively.

Description

technical field [0001] The invention belongs to the technical field of materials, and relates to a microfabrication technology, that is, an etching solution in a photolithography process, and specifically refers to an etching solution for patterning a bismuth-based thin film material by a chemical wet etching method. Background technique [0002] Microwave dielectric tunable materials are widely used in microwave voltage-controlled devices. Currently, the materials used in the microwave tunable field are mainly barium strontium titanate Ba 1-x Sr0 x TiO 3 (BST) film material. Recently discovered bismuth-based structural materials such as: zinc bismuth niobate Bi 1.5 Zn 1.0 Nb 1.5 o 7 (BZN), and magnesium bismuth niobate Bi 1.5 MgNb 1.5 o 7 (BMN) has dielectric tunable properties, moderate dielectric constant, and very low dielectric loss. These characteristics make it a promising microwave dielectric tunable material. However, it is found in the microfabrication pr...

AI Technical Summary

Problems solved by technology

[0004] The invention aims at the technical problem that it is difficult to etch the bismuth-based thin film material by using HF aqueous solution as the etching liquid, and the pattern accuracy cannot be guaranteed, and provides an etching liquid for wet etching of the bismuth-based thin film

Images