PatternPaint: Generating Layout Patterns Using Generative AI and Inpainting Techniques

Generation of diverse VLSI layout patterns is crucial for various downstream tasks in design for manufacturing (DFM) studies. However, the lengthy design cycles often hinder the creation of a comprehensive layout pattern library, and new detrimental patterns may be discovered late in the product development process. Existing training-based ML pattern generation approaches struggle to produce legal layout patterns in the early stages of technology node development due to the limited availability of training samples.To address this challenge, we propose PatternPaint, a training-free framework capable of generating legal patterns with limited DRC Clean training samples. PatternPaint simplifies complex layout pattern generation into a series of inpainting processes with a template-based denoising scheme. Our framework enables even a general pre-trained image foundation model (stable-diffusion), to generate valuable pattern variations, thereby enhancing the library. Notably, PatternPaint can operate with any input size. Furthermore, we explore fine-tuning a pre-trained model with VLSI layout images, resulting in a 2x generation efficiency compared to the base model. Our results show that the proposed model can generate legal patterns in complex 2D metal interconnect design rule settings and achieves a high diversity score. The designed system, with its flexible settings, supports pattern generation with localized changes and design rule violation correction. Validated on a sub-3nm technology node (Intel 18A), PatternPaint is the first framework to generate a complex 2D layout pattern library using only 20 design rule clean layout patterns as input.