Open Access

ARTICLE

Research on the Regulation of Polyimide Film Microstructure and Its O₂ Plasma Etching Behavior in the Drying Process

Peishuai Xing¹, Xiaodong Guo², Yang Wang^1,*, Sixi Zha¹, Zeting Chen³, Shicheng Shen¹, Bin He², Tianyun Li², Yuning Zhao²
1 School of Mechanical Engineering, XinJiang University, Urumchi, China
2 Semiconductor Technology Research Department, Ji Hua Laboratory, Foshan, China
3 South China Academy of Advanced Optoelectronics, South China Normal University, Guangzhou, China
* Corresponding Author: Yang Wang. Email:
(This article belongs to the Special Issue: Advances in Functional Polymer Composites: Synthesis, Characterization and Applications)

Journal of Polymer Materials https://doi.org/10.32604/jpm.2026.077304

Received 06 December 2025; Accepted 31 January 2026; Published online 02 April 2026

Abstract

In the fabrication of microelectronic devices, polyimide (PI) is often patterned through plasma etching. However, the relationship between its etching behavior and the precursor processing technology has not been systematically revealed. In this paper, PMDA-ODA type PI was selected as the research object. For the first time, the effects of two film-forming processes, freeze drying (FD) and thermal drying (TD), on the microstructure of PI films and their O₂ plasma etching behavior were systematically compared. By means of scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FTIR), and water contact angle testing, the intrinsic differences between the two types of films and the performance evolution rules during the etching process were clarified. The results show that the surface of the FD-PI film exhibits discrete pore structure, while the TD-PI film is characterized by a dense and non-porous structure. This structural difference leads to more significant surface morphology evolution and chemical composition changes in FD-PI during the etching process. After plasma treatment, polar oxygen-containing groups such as O=C-O were successfully introduced onto the surfaces of both types of films. The content of these groups showed regular changes with the etching time, and the wettability of the films processed by the two different technologies was characterized by a dynamic water contact angle measuring instrument. This study reveals the internal mechanism by which the drying process affects the plasma etching behavior of PI films by regulating their initial microstructure, providing important theoretical basis and process guidance for the precision processing of high-performance PI films for advanced electronic devices.

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Keywords

Polyimide films; freeze drying; plasma etching

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