Study of bilayer silylation process for 193 nm lithography using chemically amplified resist

The top surface imaging process has been studied in order to extend the lim it of photolithography down to 0.10 mu m or smaller dimensions using 193 nm or shorter wavelengths. We have been evaluating a bilayer silylation proce ss as one of the approaches to improve the lithographic performance of the silylation process. In this article, we focus on the critical dimension con trollability of the bilayer silylation process using a chemically amplified (CA) resist. The application of a CA resist is thought to be one of the pr omising approaches to increase the photospeed of the silylation process for practical applications. We investigated the effect of process issues due t o the CA resist, and evaluated the lithographic performance of this silylat ion process. The 0.13 mu m line and space (L/S) patterns were generated by 5 mJ/cm(2) exposure energy, and the 0.11 mu m L/S patterns could be generat ed without using any resolution enhancement techniques. Moreover, by applyi ng an off-axis illumination exposure technique using an attenuated phase sh ift mask, the 0.10 mu m L/S patterns were successfully fabricated with a su fficient process window. (C) 1999 American Vacuum Society. [S0734-211X(99)0 6006-0].