Corner rounding in EUV photoresist: tuning through molecular weight, PAG size, and development time

Abstract

In this paper, the corner rounding bias of a commercially available extreme ultraviolet photoresist is monitored as molecular weight, photoacid generator (PAG) size, and development time are varied. These experiments show that PAG size influences corner biasing while molecular weight and development time do not. Large PAGs are shown to exhibit less corner biasing, and in some cases, lower corner rounding, than small PAGs. In addition, heavier resist polymers are shown to exhibit less corner rounding than lighter ones.

Characteristics and durability of fluoropolymer thin films

“…Interestingly, the fragmentation of the CF x O y film often appeared to follow approximately rectangular geometries, which may correspond to the crystal structure of the underlying Si(100), and AFM images showed that the film always fractured in a unit of the full thickness of the deposited film. MF26a developer is an aqueous solution of pH 10.4 containing tetramethylammonium hydroxide (TMAH) at a molarity of 0.26 M [16]. TMAH is often used for the etching of Si [17,18] and the results presented here indicate that a CF x O y thin film does not act as a significant diffusion barrier to aqueous solutions of TMAH, and hence the etching of Si in the presence of TMAH can proceed.…”