Ablation of thermostable polymers, including polyimides, polyphenylquinoxaline and poly-vinylearbazole (Fig. 1), with the far-UV radiation of the excimer laser, provides surfaces with new properties that prove to be highly useful in microelectronics. When ablation is done in air, the surface of polyphenylquinoxaline displays a strong affinity for oxygen, as revealed by XPS, and can be wetled selectively by water or high surface energy liquids, thanks to the high contact angle hysteresis with null receding contact angle, produced on irradiated surfaces (Fig. 2). These new properties? do not appear when ablation of the same materials is performed under vacuum or in an atmosphere not containing oxygen.
© 1991 Optical Society of AmericaPDF Article