High-performance fracturing for variable shaped beam mask writing machines

Schulze, Steffen; Sahouria, Emile; Miloslavsky, E.

doi:10.1117/12.504274

Cited by 10 publications

(10 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Although the processing of layouts is much slower than in commercial products, we note that no effort has been spent on code optimizations. We believe that the ILP-based heuristic framework is scalable to full-chip layout processing, particularly when fracturing is done hierarchically (cf., e.g., 2 ) and/or in a distributed fashion.…”

Section: Discussionmentioning

confidence: 99%

“…A different technological aspect of the Fracturing Problem has been addressed in a recent series of papers by Shulze et al 2 and Cobb et al 6,7 In the standard data preparation flow for VSB mask writing, a post-RET layout in GDSII format is transferred into the MEBES mask writing format, which is then further transferred into VSB formats supported by various VSB mask writing machines. The drawback of this flow is that GDSII and VSB formats are hierarchical, while MEBES does not support hierarchy.…”

Section: Previous Workmentioning

confidence: 99%

See 1 more Smart Citation

Yield- and cost-driven fracturing for variable shaped-beam mask writing

Kahng

Zelikovsky

2004

SPIE Proceedings

View full text Add to dashboard Cite

Mask manufacturing for the approaching 90nm and 65nm nodes increasingly deploys variable shaped beam (VSB) mask writing machines. This has led to high interest in the fracturing methods which are at the heart of layout data preparation for VSB mask writing. In this paper, we set out the main requirements for fracturing and suggest a new solution approach based on integer linear programming (ILP). The main advantage of the new method is that the ILP finds optimal solutions while being flexible enough to take into account all specified requirements. We also suggest several decomposition (polygon partitioning) heuristics which speed up the ILP approach. Experimental comparisons with leading industry tools show significant improvement in quality, as well as acceptable scalability, of the proposed methods. In particular, our fracturing solutions reduce shot count (which reflects write time and mask cost) and dramatically reduce sliver count (which reflects the risk of mask critical-dimension errors). Our results reveal significant headroom that can be exploited by future design-to-mask tools to reduce the manufacturing variability and cost of IC designs.

show abstract

Section: Discussionmentioning

confidence: 99%

Section: Previous Workmentioning

confidence: 99%

Yield- and cost-driven fracturing for variable shaped-beam mask writing

Kahng

Zelikovsky

2004

SPIE Proceedings

View full text Add to dashboard Cite

show abstract

“…Mask writing times beyond 24 hours have been reported and are one of the major contributors of the increasing mask costs as the feature sizes are shrinking. It has been shown that the fracturing itself can be optimized by conducting it in a hierarchical flow with an algorithm that focuses on the suppression of small figures while seeking the optimum trapezoiding for a minimum shot count [3]. The flow based on hierarchical data (GDSII) provides a small output file size and has the fastest turn around time in the data processing [4].…”

Section: Introductionmentioning

confidence: 99%

“…The flow based on hierarchical data (GDSII) provides a small output file size and has the fastest turn around time in the data processing [4]. The influence of the complexity of OPC on the performance parameters of the VSB-fractured output has been widely discussed in the data preparation community [3,5,6]. Based on the knowledge of the performance parameters for the VSB fracturing this paper will investigate opportunities to optimize the setup of the optical proximity correction for an output that produces reduced trapezoid and shot counts thus reducing the mask writing time.…”

Section: Introductionmentioning

confidence: 99%

“…Small trapezoids do not contribute significantly to cover the area of the mask and are hence not desirable. It was previously shown that jogs introduced by the OPC are one of the causes for them [3]. In order to answer the question of where to focus the effort in the optimization of the OPC in a preliminary study we investigated the magnitude of the impact of small figures on the total trapezoid count.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Optimization of data handling prior to fracturing for reduction of mask writing time

Word

Schulze

2003

SPIE Proceedings

Self Cite

View full text Add to dashboard Cite

As the industry is targeting the sub-100nm nodes, the pressure on the data path and tapeout flow is growing. Design complexity and increased deployment of resolution enhancement techniques (RET) result in rapidly growing file sizes, which turns what used to be the relatively simple task of mask data preparation into a real bottleneck. Previous work indicated that the properties of the incoming layout ñ hierarchy, grid, aggressiveness of the RET solution have a major impact on the performance of fracturing and mask writing The tuning of OPC can reduce itís impact on subsequent fracturing. This study investigates the impact of OPC setup-various fragmentation parameters like fragment length, density, interaction radius and, various line-end correction schemes on the performance parameters for the mask data preparation and mask writing. Parameters like run-time, file size, shot count and small figures will be reported in dependence on the input layout preparation history. Approaches to optimize the integrated RET and MDP flow while maintaining manufacturability and the required CD control are introduced and evaluated.

show abstract

Benchmarking of Mask Fracturing Heuristics

Chan

Gupta

Han

et al. 2017

IEEE Trans. Comput.-Aided Des. Integr. Circuits Syst.

View full text Add to dashboard Cite

Aggressive resolution enhancement techniques such as inverse lithography (ILT) often lead to complex, non-rectilinear mask shapes which make mask writing extremely slow and expensive. To reduce shot count of complex mask shapes, mask writers allow overlapping shots, due to which the problem of fracturing mask shapes with minimum shot count is NP-hard. The need to correct for e-beam proximity effect makes mask fracturing even more challenging. Although a number of fracturing heuristics have been proposed, there has been no systematic study to analyze the quality of their solutions. In this work, we propose a new method to generate benchmarks with known optimal solutions that can be used to evaluate the suboptimality of mask fracturing heuristics. We also propose a method to generate tight upper and lower bounds for actual ILT mask shapes by formulating mask fracturing as an integer linear program and solving it using branch and price. Our results show that a state-of-the-art prototype [version of] capability within a commercial EDA tool for e-beam mask shot decomposition can be suboptimal by as much as 3.7× for generated benchmarks, and by as much as 3.6× for actual ILT shapes.

show abstract

High-performance fracturing for variable shaped beam mask writing machines

Cited by 10 publications

References 0 publications

Yield- and cost-driven fracturing for variable shaped-beam mask writing

Yield- and cost-driven fracturing for variable shaped-beam mask writing

Optimization of data handling prior to fracturing for reduction of mask writing time

Benchmarking of Mask Fracturing Heuristics

Contact Info

Product

Resources

About