Process optimization consideration for 193nm developable bottom anti-reflective coatings (DBARCs)

Abstract

Developable BARCs (DBARCs) are useful for implant layers because they eliminate the plasma etch step avoiding damage to the plasma sensitive layers during implantation. It is expected that DBARC will also be used for non-implant layers and double exposure technology. AZ has pioneered DBARC based on photosensitive cleave as well as crosslink/decrosslink mechanisms. In this paper, we focus on various processing factors for 193nm DBARC and discuss the influences of prewet, thickness, topography and substrates on lithographic performance. Prewet of DBARC before resist coating deteriorated performance, however, it was resolved by modifying DBARC formulations. The optimized DBARC showed both optical and lithographic performance comparable to conventional BARCs. DBARCs minimized reflection from the substrates and notching of patterns was improved observed on silicon oxide topography. This paper includes simulation, DBARC contrast curve analyses, and recent dry and immersion exposure results of DBARC.

PAG and Quencher Effects on DBARC Performance

“…Photosensitive DBARCs have photoimageable properties and resolve patterns irrespective of upper resist layer [9][10][11][12][13][14][15][16][17][18]. Therefore, they have better resolution and through-pitch performance which are required for logic devices and critical layers.…”

Design and Development of Developable BARCs (DBARCs) for Advanced Lithographic Applications

“…[7][8][9][10] In these cases, interest in DBARC technology is typically driven by cost of ownership (COO) concerns. Again the ability to retain reflection control but eliminate the ARC open etch step is appealing from the standpoint of lowering COO The attributes outlined above suggest DBARC technology is well suited to address many of today's advanced patterning needs.…”

“…[8][9][10][11][12][13][14] In addition to research by material vendors, several device makers have and continue to evaluate DBARC technology as the search for a production worthy DBARC continues.…”