Surface modification and electroless copper plating of PI film

PI film is a high-performance material of polyimide, characterized by high temperature stability, high mechanical strength, high chemical stability, and excellent electrical properties. It is widely used in fields such as electronics and aerospace. This article will introduce the surface modification of PI film and its application in electroless copper plating.

1、 Surface modification of PI film
    pi filmSurface modification can be achieved through various methods, including plasma modification, chemical modification, and coating of functional materials. The modified PI film can improve its surface adhesion, hydrophilicity, conductivity and other properties, thereby expanding its application fields.

1. Plasma modification
Plasma modification is a method of improving the surface properties of PI thin films by treating their surface with oxygen plasma to alter their chemical composition. Plasma can break chemical bonds on the surface of PI films at low temperatures, generating functional groups such as hydroxyl and carboxyl groups, increasing the hydrophilicity and adhesion of PI film surfaces. Meanwhile, plasma can also alter the charge state on the surface of PI thin films, improving their conductivity. Plasma modification can be achieved by changing the plasma treatment conditions (such as gas type, treatment time, gas pressure, etc.), which has the advantages of easy operation and significant effects.

2. Chemical modification
Chemical modification is a method of altering the surface properties of PI thin films by introducing new functional groups through chemical reactions with the film surface. For example, modifying the surface of PI film with compounds containing functional groups such as hydroxyl, amino, and amide groups can improve its surface adhesion, hydrophilicity, and conductivity. Chemical modification requires the selection of appropriate chemical reagents, control of reaction conditions and reaction time to avoid adverse effects on the physical properties of PI films.

3. Coating functional materials
Coating functional materials is a method of changing the surface properties of PI films by coating them with materials with specific functions. For example, coating the surface of PI film with conductive material can improve its conductivity; Coating the surface of PI film with hydrophilic material can improve its surface hydrophilicity. Coating functional materials requires selecting appropriate coating processes and materials to form a uniform and stable coating on the surface of PI films, with good adhesion and durability.

2、 Chemical copper plating
Chemical copper plating is a method of depositing a layer of copper film on the surface of PI film to improve its conductivity and mechanical strength. The process of electroless copper plating is divided into three steps: surface activation, catalysis, and deposition. Surface activation is achieved by coating an activation solution on the surface of a PI film and activating its surface at a certain temperature and time for subsequent catalysis and deposition. Catalysis is the process of coating the surface of a PI thin film with a catalyst to give it catalytic properties and promote the reduction of copper ions to form a copper film. Deposition is the process of immersing a PI film in a solution containing copper ions and conducting an electrochemical reaction under certain conditions to reduce copper ions and form a copper film. Chemical copper plating can control the thickness and structure of copper films by changing the composition, concentration, and reaction conditions of catalysts and deposition solutions.

3、 Summary
Surface modification of PI film and chemical copper plating are key technologies for expanding the application and improving the performance of PI film. Surface modification of PI thin films can be achieved through various methods such as plasma treatment, chemical modification, and coating of functional materials, thereby improving their surface adhesion, hydrophilicity, conductivity, and other properties. Chemical copper plating can be achieved through surface activation, catalysis, and deposition steps to coat the surface of PI thin films with a layer of copper film, thereby improving their conductivity and mechanical strength. The application of these technologies can expand the scope of PI thin films in fields such as electronics and aerospace, and enhance their application value.