隨著半導體產業的不斷發展，晶片中元件的尺寸變得愈來愈小，同時光罩圖形的微縮速率也和晶片同步。目前，先進的微影技術主要依賴於電子束微影系統（e-beam Lithography）來實現高精度的光罩製作。在本次實驗中，我們使用電子束微影系統對光罩進行曝光。然而，隨著曝光尺寸的逐漸縮小，電子束鄰近效應變得愈發顯著，導致圖案失真和變形。
電子束鄰近效應是由於電子束在曝光過程中產生的散射和背散射現象，這些現象會影響周圍區域的強度分佈，從而引起圖案的模糊和失真。傳統的鄰近效應修正方法通常需要複雜的迭代計算，難以在高精度和高效率之間取得平衡。因此，本次實驗致力於開發一種新的電子束微影鄰近效應修正系統，以降低鄰近效應對光罩製作的影響。
本次研究基於雙高斯模型來模擬電子束的散射效應，並利用維納反卷積（Wiener Deconvolution）技術進行圖像修復。雙高斯模型能夠準確描述電子束的散射行為，而維納反卷積則對高頻訊號進行反卷積的運算，而在低頻訊號的部分則進行電子束微影鄰近效應的修正，這也使得修復後的圖案更加精細和準確。
實驗結果顯示，使用本次實驗開發的鄰近效應修正系統，能夠顯著改善電子束曝光後的圖案品質，減少失真和變形，提高光罩製作的精度和一致性。這一成果對於推動半導體製程的進一步微縮具有重要意義，能夠有效支持未來高性能晶片的研發和生產。

As the semiconductor industry continues to grow, the size of the devices in chips is becoming smaller. This demands higher precision in the miniaturization of photomask patterns. Currently, advanced lithography techniques primarily rely on e-beam lithography for high-precision photomask fabrication. In this work, we used an e-beam lithography system to expose photomask pattern. However, as the pattern dimensions decrease, the e-beam proximity effect becomes more pronounced, leading to pattern distortion and deformation.
The e-beam proximity effect is caused by forward scattering and backscattering of the electrons by the exposure medium during exposure. These scatterings affects the intensity distribution in the vicinity of the beam, resulting in pattern blur and distortion. Traditional e-beam proximity correction methods often require complex iterative calculations, making it difficult to balance high precision and high efficiency. Here, this study is dedicated to developing a new e-beam proximity effect correction scheme to reduce the impact of the proximity effect on photomask fabrication.
This study simulates the scattering effects of electron beams based on a double Gaussian model and employs the Wiener Deconvolution techniques for image restoration. The double Gaussian model accurately describes the scattering behavior of electron beams, while the Wiener Deconvolution performs deconvolution operations on high-frequency signals and corrects e-beam proximity effects for low-frequency signals. This approach results in a more refined and accurate restoration of the patterns.
Experimental results show that the proximity effect correction system developed in this study significantly improves the quality of the patterns after e-beam exposure, reducing distortion and deformation, and enhancing the precision and consistency of photomask fabrication. This achievement is of great significance for further miniaturization in semiconductor manufacturing, effectively supporting the development and production of future high-performance chips.

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