Table of Contents
Fetching ...

Unitho: A Unified Multi-Task Framework for Computational Lithography

Qian Jin, Yumeng Liu, Yuqi Jiang, Qi Sun, Cheng Zhuo

TL;DR

Unitho tackles the computational bottlenecks of lithography by presenting a unified multi-task Transformer framework that merges end-to-end mask/contour generation, lithography simulation, and hotspot detection into a single, process-aware pipeline. It employs a cross-attention fusion mechanism to integrate layout with process conditions and uses contrastive learning to sharpen structural and process sensitivity, with a three-stage training strategy (generation pre-training, detection pre-training, and joint fine-tuning). Evaluated on a large-scale industrial dataset, Unitho achieves state-of-the-art generation and detection performance, while delivering massive speedups (e.g., ~85× faster than a commercial tool) and close agreement with traditional simulators for LRC hotspots. The approach enables rapid PWV, improved design-for-manufacturing feedback, and scalable DTCO across diverse process conditions.

Abstract

Reliable, generalizable data foundations are critical for enabling large-scale models in computational lithography. However, essential tasks-mask generation, rule violation detection, and layout optimization-are often handled in isolation, hindered by scarce datasets and limited modeling approaches. To address these challenges, we introduce Unitho, a unified multi-task large vision model built upon the Transformer architecture. Trained on a large-scale industrial lithography simulation dataset with hundreds of thousands of cases, Unitho supports end-to-end mask generation, lithography simulation, and rule violation detection. By enabling agile and high-fidelity lithography simulation, Unitho further facilitates the construction of robust data foundations for intelligent EDA. Experimental results validate its effectiveness and generalizability, with performance substantially surpassing academic baselines.

Unitho: A Unified Multi-Task Framework for Computational Lithography

TL;DR

Unitho tackles the computational bottlenecks of lithography by presenting a unified multi-task Transformer framework that merges end-to-end mask/contour generation, lithography simulation, and hotspot detection into a single, process-aware pipeline. It employs a cross-attention fusion mechanism to integrate layout with process conditions and uses contrastive learning to sharpen structural and process sensitivity, with a three-stage training strategy (generation pre-training, detection pre-training, and joint fine-tuning). Evaluated on a large-scale industrial dataset, Unitho achieves state-of-the-art generation and detection performance, while delivering massive speedups (e.g., ~85× faster than a commercial tool) and close agreement with traditional simulators for LRC hotspots. The approach enables rapid PWV, improved design-for-manufacturing feedback, and scalable DTCO across diverse process conditions.

Abstract

Reliable, generalizable data foundations are critical for enabling large-scale models in computational lithography. However, essential tasks-mask generation, rule violation detection, and layout optimization-are often handled in isolation, hindered by scarce datasets and limited modeling approaches. To address these challenges, we introduce Unitho, a unified multi-task large vision model built upon the Transformer architecture. Trained on a large-scale industrial lithography simulation dataset with hundreds of thousands of cases, Unitho supports end-to-end mask generation, lithography simulation, and rule violation detection. By enabling agile and high-fidelity lithography simulation, Unitho further facilitates the construction of robust data foundations for intelligent EDA. Experimental results validate its effectiveness and generalizability, with performance substantially surpassing academic baselines.

Paper Structure

This paper contains 20 sections, 18 equations, 5 figures, 6 tables.

Figures (5)

  • Figure 1: Workflow Comparison. (a) Traditional processing flow of commercial tools; (b) Unitho’s substitution role, accelerating iterations.
  • Figure 2: Runtime Comparison of Commercial Tool and Unitho on 6000 × 6000 nm layout clips. Time cost breaks into 3 stages: OPC, Lithography Simulation, and Verifications (DRC+MRC+LRC), with the commercial tool executed on a 20-core Intel Xeon Platinum server for 30 OPC iterations.
  • Figure 3: The framework of Unitho.
  • Figure 4: Generated results under representative process conditions, with each pair showing predicted mask (top) and contour (bottom).
  • Figure 5: Comparison of detection results.