Fast simulation of stochastic exposure distribution in electron-beam lithography
نویسندگان
چکیده
The relative critical dimension variation of nanoscale features has become large enough to significantly affect the minimum feature size and maximum circuit density realizable in most lithographic processes. One source of such variation is the line edge roughness (LER). In the electron-beam lithographic process, the fluctuation of exposure (energy deposited) in the resist is one of the main factors contributing to the LER. It is essential to accurately estimate the exposure fluctuation for developing an effective method to reduce the LER. A possible method is to rely on the Monte Carlo simulation in computing the exposure distribution in a circuit pattern, i.e., generating a point spread function (PSF) for each point to be exposed, where the PSF is stochastic. While this approach can lead to a more realistic estimation, it is not practical due to its tremendous amount of computation required. In this paper, a new method to greatly reduce the number of PSF’s to be generated without sacrificing the accuracy of estimating the exposure fluctuation is described. It generates only a small number of stochastic PSF’s and uses them randomly in the exposure calculation for a circuit pattern. Through an extensive simulation, it is shown that the new method is statistically equivalent to generating a PSF for each point with an acceptable error. Since it is not necessary to know the exact spatial distribution of exposure for estimation of the LER, the new method has a good potential to be employed in practice to reduce the computation time by orders of magnitude. VC 2012 American Vacuum Society. [http://dx.doi.org/10.1116/1.4767447]
منابع مشابه
Computer Simulation of Electron and Ion Beam Lithography of Nanostructures
In this paper a review of the authors results on mathematical modeling of the processes at electron or ion beam lithography of nanostructures is presented. Our Monte Carlo simulation tools for electron and ion exposures are successfully applied for the energy deposition calculation at electron or ion lithography of resist layers. At ion lithography electronic energy losses of penetrating electr...
متن کاملComputer Simulation from Electron Beam Lithography to Optical Lithography
Simulation of electron beam lithography and optical lithography has been combined to investigate the influence of a distorted photomask feature on final photoresist image. Unlike the previous optical lithography simulation which was based on ideal mask design, the combined simulation has shown that mask distortion due to electron proximity effect play an important role in worsening the optical ...
متن کاملComputer Simulation of Processes at Electron and Ion Beam Lithography, Part 2: Simulation of Resist Developed Images at Electron and Ion Beam Lithography
متن کامل
Monte Carlo Simulation of a Linear Accelerator and Electron Beam Parameters Used in Radiotherapy
Introduction: In recent decades, several Monte Carlo codes have been introduced for research and medical applications. These methods provide both accurate and detailed calculation of particle transport from linear accelerators. The main drawback of Monte Carlo techniques is the extremely long computing time that is required in order to obtain a dose distribution with good statistical accuracy. ...
متن کاملEffect of Tissue Composition on Dose Distribution in Electron Beam Radiotherapy
Objective: The aim of this study is to evaluate the effect of tissue composition on dose distribution in electron beam radiotherapy.Methods: A Siemens Primus linear accelerator and a phantom were simulated using MCNPX Monte Carlo code. In a homogeneous cylindrical phantom, six types of soft tissue and three types of tissue-equivalent materials were investigated. The tissues included muscle (ske...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
دوره شماره
صفحات -
تاریخ انتشار 2012