公开(公告)号：US20250085241A1

公开(公告)日：2025-03-13

申请号：US18367364

申请日：2023-09-12

Applicant: KLA Corporation

Inventor： Rebecca Shen ,  Sandeep Inampudi ,  Boxue Chen ,  Bindi Nagda ,  John J. Hench ,  William McGahan

IPC: G01N23/207

Abstract: Methods and systems for performing X-ray model based scatterometry measurements of semiconductor structures with reduced computational effort are described herein. More specifically, measured detector image data is transformed to diffraction order efficiency data. The measured diffraction order efficiency data is compared with a parameter-efficiency library including simulated diffraction order efficiency data and associated sets of specimen parameter values. One or more sets of specimen parameter values are selected as seed values for regression on the measured detector image data based on the fit between the measured and simulated diffraction order efficiency data. The seed values are provided as initial values of one or more parameters of interest for the first iteration of the regression. The seed values enable the image based regression to converge to the global minimum with a dramatically reduced number of iterations. Thus, accurate X-ray scatterometry measurements of complex semiconductor structures are realized with less computational effort.

公开(公告)号：US20240302301A1

公开(公告)日：2024-09-12

申请号：US18416113

申请日：2024-01-18

Applicant: KLA Corporation

Inventor： Sandeep Inampudi ,  Hyowon Park ,  Daniel Haxton ,  Boxue Chen ,  Sungchul Yoo ,  Robert D. Press

IPC: G01N23/205 ,  G01N23/2055 ,  H01L21/66

CPC classification number: G01N23/205 ,  G01N23/2055 ,  G01N2223/6116 ,  H01L22/12

Abstract: Methods and systems for performing measurements of stacked semiconductor structures, e.g., stacked memory and logic structures, based on X-Ray transmission scatterometry measurement data are described herein. In some examples, the scattering response of logic structures is modelled directly in signal space by a mathematical expression including a relatively small number of weighted basis functions. The scattering response of the logic structures and the scattering response of the memory structures determined by an electromagnetic response model are combined, e.g., by summation or convolution. The combined modelled signals are compared to the measured signals at the detector to generate an error signal. The error signal is employed to drive a regression analysis employed to optimize parameter values characterizing the memory structures, values of the weighting coefficients of the signal space model, or both. In other examples, the scattering response of the logic structures is known, and a model is not needed.