Paper 13216-113
Curvilinear Masks: Motivations and Metrology (Invited Paper)
3 October 2024 • 8:00 AM - 8:20 AM PDT | Monterey Conf. Ctr., Steinbeck 2
Abstract
The photomask industry is experiencing a fundamental shift from Manhattan masks to curvilinear masks. Recent lithography and mask technology conferences have featured many papers and talks on curvilinear masks, curvilinear OPC, curvilinear ILT, curvilinear mask process correction (MPC), and curvilinear mask formats. Step by step, the photomask industry has started a transition from Manhattan to curvilinear, enabled by the adoption of the new multi-beam mask writers and the advent of practical full-chip curvilinear inverse lithography technology (ILT). The benefits of curvilinear masks go much deeper than is immediately obvious. In this paper we will share our insight on the motivations for the mask world to move toward curvilinear mask shapes. We will evaluate the benefits of curvilinear mask shapes in terms of process window, mask rules, mask error enhancement factor (MEEF), and mask variation. In addition, we will propose a new specification for curvilinear mask metrology, as an equivalent to critical dimension (CD), and we will also demonstrate that curvilinear masks have a tighter mask process variation (PV) band than Manhattan masks using this proposed specification.
Presenter
D2S, Inc. (United States)
Dr. Linyong (Leo) Pang has been the Chief Product Officer and Executive VP at D2S since 2014, leading the TrueMask mask data preparation products and the new generation full-chip curvilinear inverse lithography technology (ILT) products using GPU acceleration. Prior to D2S, Leo was Sr. Vice President of Computational Lithography and Inspection Technologies at Luminescent Technologies. He joined the Luminescent executive team from its beginning in 2004 and pioneered the development of ILT products (acquired by Synopsys in 2012) and, later on, the Computational Metrology and Inspection business until it was acquired by KLA-Tencor in March 2014. His pioneering work in EDA and semiconductors started back 1999 at Numerical Technologies as the inventor and product manager of the i-Virtual Stepper System. Leo has 38 issued patents, 27 pending patents and 90 publications. Leo was recognized as an SPIE Fellow in 2023. Leo received his M.S. in Computer Science and Ph.D. in Mechanical Engineering