Method for reducing lateral erosion amount of copper microelectrode of piezoelectric ink-jet printing head by adopting multi-step corrosion

Abstract

The invention belongs to the technical field of metal microelectrode preparation in the field of MEMS, and relates to a method for reducing the lateral erosion amount of a copper microelectrode of a piezoelectric ink-jet printing head through multi-step corrosion. In the method for preparing a copper microelectrode of a piezoelectric ink-jet printing head by adopting a multi-step corrosion method,a copper electrode masking layer is prepared by using a photoetching process in an MEMS technology, the surface of an exposed copper electrode is corroded to generate an intermediate product CuCl, and a solution capable of removing CuCl without corroding copper is used for corroding CuCl to obtain a copper microelectrode structure with small lateral erosion. By adopting the method disclosed by the invention, the residence time of the copper electrode in the FeCl3 solution can be greatly reduced, so that the lateral erosion amount of the side wall of the copper electrode is effectively reduced, and the corrosion uniformity is improved. The piezoelectric ink-jet printing head copper microelectrode structure prepared by the method is simple in manufacturing process, low in cost and good in process repeatability.

Description

technical field [0001] The invention belongs to the technical field of metal microelectrode preparation in the field of MEMS, and in particular relates to a method for reducing the amount of side erosion of a copper microelectrode of a piezoelectric inkjet printing head by using multi-step corrosion. Background technique [0002] Piezoelectric inkjet printing technology has been expanded from the traditional printing industry to the fields of electronics, biology and rapid prototyping technology due to its advantages of miniaturization, mass production and long life; as the driving element of piezoelectric inkjet printing head, electrodes Material selection, manufacturing quality, and patterning process have a great influence on the vibration amplitude and vibration shape of the overall device. Metal Cu has been widely used in the field of microelectronic devices due to its excellent electrical conductivity, thermal conductivity and elasticity, and it is mostly used in the f...

AI Technical Summary

Problems solved by technology

There are many types of wet etching solutions for Cu thin films. Li Jia et al. used nitric acid-based etching solutions to etch Cu, and studied the effects of different concentrations of nitric acid on the corrosion rate and side etching, but the solution has certain limitations on the substrate. Moreover, strong acid operation is less safe and difficult to handle; Cai Jian et al. used FeCl3 solution to corrode Cu, and studied the corrosion rate of Cu in FeCl3 solution. The formation mechanism of CuCl, etc.; in addition, the alkaline etching solution composed of ammonia water, ammonium chloride and copper chloride can also corrode Cu, but the alkaline etching solution will change the properties of the positive photoresist masking layer, resulting in Positive glue remains on the structure and is not easy to remove

Moreover, when Cu is corroded in a one-step etching process, due to errors in the environment, preparation concentration, and operating methods, the time for corroding Cu cannot be accurately controlled, resulting in excessive side erosion due to the prolonged stay in the etching solution.

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