The Study on the Determination of Proximity Parameters and Proximity Effect Correction in Electron Beam Lithography

• Main Authors: Wu, Mei-Jen, 吳玫真
• Other Authors: Loong, Wen-An
• Format: Others
• Language: zh-TW
• Published: 1997
• Online Access: http://ndltd.ncl.edu.tw/handle/60586433993911693663

碩士 === 國立交通大學 === 應用化學研究所 === 85 === 　　As the critical dimensions of integrated circuit technology continue to shrink, the E-beam proximity effect correction is indispensable for precise line width control of mask. Using simple and precise experiment method to carry out E-beam proximity effect correction is a hot and an important research topic in the past decades. 　　The E-beam proximity parameters are related with the beam accelerating voltage, substrate material, the resist properties, resist thickness, resist contrast and the development process etc. Various methods for the determination of the proximity parameters have been reported. Among many experimental methods, the doughnut method reported by the L.Stenvens is the easiest way for the determination of the parameters of scattering, however, it is difficult to determine the forward scattering parameter because of the beam current instability of the E-beam writer and the uncertainty from scanning electron microscope (SEM) measurement. 　　In this thesis, the doughnut method coupled with the double lines method are used. Besides using double lines method instead of doughnut method to overcome the problem of determination of the forward scattered parameter, further more, doughnut method has been extended and applied successfully to determine the proximity parameters of the third Gaussian. Using line method of increasing expose dose stepwise instead of large square pattern method to determine the critical dose of the resist, the precision of the proximity parameters can be improved. The advantage and the disadvantage of the double and triple Gaussian functions were also compared. In the Proximity effect correction, the application of the obtained optical parameters and Mathematical software to carry out the preliminary dose correction, resulted in good proximity effect correction. After dose correction, the line-width difference between the center and edge of the 0.2 μm L/S＝1 patterns reduced from 23.5% to 0.54% and kept critical dimension within ±10%. 　　By our experiment, it is concluded that the doughnut method coupled with double lines method are a fast and precise method for the determination of the proximity parameters.