Korean Journal of Optics and Photonics (한국광학회지)

Optical Society of Korea (한국광학회)
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A Study on the Measurement of Dill and Mack Model Parameters of a Photoresist

포토레지스트의 Dill 및 Mack 모델 파라미터 측정에 관한 연구

  • Park, Seungtae (Department of Photonic Engineering, Chosun University) ;
  • Kwon, Haehyuck (Department of Photonic Engineering, Chosun University) ;
  • Park, Jong-Rak (Department of Photonic Engineering, Chosun University)
  • 박승태 (조선대학교 광기술공학과) ;
  • 권해혁 (조선대학교 광기술공학과) ;
  • 박종락 (조선대학교 광기술공학과)
  • Received : 2022.11.04
  • Accepted : 2022.11.22
  • Published : 2022.12.25
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Abstract

We measured the Dill and Mack model parameters that determine the exposure and development characteristics of photoresists, respectively. First, photoresist samples were prepared while altering the exposure dose, and changes in transmittance were measured. Analyzing these results, the Dill model parameters A, B, and C were determined. In particular, the exact solution of the Dill model equation was used to determine the C parameter. In addition, changes in thickness were measured as a function of development time for different exposure doses, and the Mack model parameters Rmin, Rmax, a, and n were determined using the results. We also determined parameter values for the reduced Mack model that uses only three parameters, Rmin, Rmax, and n. The root mean square error between the model predictions and the measured values for the photoresist thickness was found to increase slightly compared to the case using the original Mack model with four parameters.

포토레지스트의 노광 및 현상 특성을 각각 결정하는 Dill 및 Mack 모델 파라미터들을 측정하였다. 먼저, 노광량을 변화시켜가며 포토레지스트 샘플을 준비하였고, 노광량에 따른 투과율 변화를 측정하였다. 이 결과를 바탕으로 Dill 모델의 A, B, C 파라미터를 결정하였는데, 특히 C 파라미터를 결정하기 위하여 Dill 모델 방정식의 완전해를 사용하였다. 또한, 노광량별로 현상 시간에 따른 포토레지스트의 두께 변화를 측정하였고, 이 결과를 사용하여 Mack 모델의 Rmin, Rmax, a, n 파라미터를 결정하였다. 모델 파라미터 Rmin, Rmax, n만을 사용하는 간략화된 Mack 모델에 대해서도 파라미터값들을 결정해 보았는데, 네 개의 파라미터를 사용하는 본래 Mack 모델의 경우와 비교했을 때 측정결과와의 오차가 다소 커짐을 알 수 있었다.

Keywords

Acknowledgement

포토레지스트 샘플 준비와 측정에 도움을 주신 Hao Cui 박사님과 Tom D. Milster 교수님께 감사드립니다.

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