DSA planarization approach to solve pattern density issue

Barros, P. Pimenta; Gharbi, Ahmed; Sarrazin, A; Tiron, Raluca; Possémé, N.; Barnola, S.; Bos, S.; Tallaron, C.; Claveau, G.; Chevalier, Xavier; Argoud, Maxime; Servin, Isabelle; Navarro, Christophe; Nicolet, Célia; Lapeyre, C.; Monget, C.

doi:10.1117/12.2086810

Cited by 9 publications

(2 citation statements)

References 7 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In this paper, in order to balance the BCP film thickness over template density, we propose a new and simple graphoepitaxy process flow called “DSA planarization” for contact‐hole patterning. The DSA planarization process enables to make the BCP film thickness uniform inside the cavities regardless of their densities, by means of appropriate BCP spin‐coating and subsequent etch‐back step . In this work, simulations of BCP self‐assembly overfilling the guiding patterns are performed in order to understand and predict the behavior of BCP self‐assembly during the DSA planarization process, i.e., when the BCP film overfills the guiding patterns.…”

Section: Introductionmentioning

confidence: 99%

Balancing Block Copolymer Thickness over Template Density in Graphoepitaxy Approach

Barros

Gharbi

Fouquet

et al. 2017

Macro Materials & Eng

View full text Add to dashboard Cite

Directed self‐assembly (DSA) of block copolymers (BCP) is one of the most promising patterning solutions for sub‐10 nm nodes. While significant achievements are demonstrated in pattern fidelity for various applications (contact shrink, line patterning), some challenges are still needed to be overcome especially regarding the defect density reduction, in order to ensure DSA insertion in high‐volume manufacturing. In particular, in the case of the graphoepitaxy approach, a remaining challenge is to solve the pattern‐densities‐related defect issue due to BCP film thickness variation inside the guiding template. In order to address this issue, a new DSA process flow called “DSA planarization” is employed for contact‐hole patterning, and consists in overfilling the guiding pattern cavities with a thick BCP film, followed by a plasma etch‐back step. This new approach ensures a uniform control of the final thickness of the BCP inside guiding cavities of different densities, as demonstrated herein by AFM measurement. Thus, defect‐free isolated and dense patterns for both contact shrink and multiplication are simultaneously resolved. Furthermore, the simulation results of BCP self‐assembly overfilling the templates demonstrate that BCP domains are well‐directed in vertical cylinders ordering inside guiding cavities, which confirms the experimental results and the viability of this approach.

show abstract

Section: Introductionmentioning

confidence: 99%

Balancing Block Copolymer Thickness over Template Density in Graphoepitaxy Approach

Barros

Gharbi

Fouquet

et al. 2017

Macro Materials & Eng

View full text Add to dashboard Cite

show abstract

“…An alternative approach is DSA planarization. 9 However, in order to thoroughly address this issue, it is crucial to get more insight into all parameters that determine template fill. In addition, the influence of template fill on the resulting morphology and the subsequent pattern transfer should be investigated.…”

Section: Introductionmentioning

confidence: 99%

Influence of template fill in graphoepitaxy DSA

et al. 2016

View full text Add to dashboard Cite

Directed self-assembly (DSA) of block copolymers (BCP) is considered a promising patterning approach for the 7-nm node and beyond. Specifically, a graphoepitaxy process using a cylindrical phase BCP may offer an efficient solution for patterning randomly distributed contact holes with subresolution pitches, such as found in via and cut mask levels. In any graphoepitaxy process, the pattern density impacts the template fill (local BCP thickness inside the template) and may cause defects due to over-or underfilling of the template. In order to tackle this issue thoroughly, the parameters that determine template fill and the influence of template fill on the resulting pattern should be investigated. Using three process flow variations (with different template surface energy), template fill is experimentally characterized as a function of pattern density and film thickness. The impact of these parameters on template fill is highly dependent on the process flow, and thus prepattern surface energy. Template fill has a considerable effect on the pattern transfer of the DSA contact holes into the underlying layer. Higher fill levels give rise to smaller contact holes and worse critical dimension uniformity. These results are important for DSA-aware design and show that fill is a crucial parameter in graphoepitaxy DSA.

show abstract