We discuss the importance of resist loss in resist calibration under multi-patterns and put it into resist calibration flow. The work is based on the exposure-focus data matrix which includes a mass of CD values obtained by experiments with step-variation setting of exposure and focus in ArF lithography. We focus on the Root-Mean-Square-Error (RMSE) between experiments and simulations for calibration. The model after calibration with only CD values including could predict that the RMS is low to 2nm for single pattern, and to 5nm for several pattern. However, the cross section image predicted by the aforementioned model is not correspond with the experiment scan imagery. The resist loss adding to flow could improve that and increase the model predictability. Most importantly, it will be shown that calibrated resist models based on several patterns data could predict the resist profile of the other patterns.
It is possible to plan mass production by multiple patterning technology of 193 immersion scanner at 7nm technology node. Source mask optimization (SMO) is essential for critical layers, which is a long-running job. It is practicable to explore the methodology to shorten the iterative process of SMO. The different initial sources for SMO of freeform source have little impact on runtime, final source shape and process window (PW) because the algorithm tries to avoid getting stuck in a local optimal solution. However, the number of patterns involved in SMO has obvious positive correlation with runtime. Our paper put forward a novel acceleration workflow for reducing the number of candidates in SMO to reduce the total runtime, and get qualified overlapped PW and improve optimization efficiency. The proposed methodology is demonstrated on leading logic technology node. The results show the feasibility to apply the method for runtime decrease and performance improvement.
It is of tremendous impact with multilayer defects, which are caused by particles, substrate pits or scratches, in EUV lithography for the high volume manufacturing. Multilayer defects suppress the productivity and utilization rate of the mask blank. In this paper, we did a thorough investigation by conducting imaging simulations on dense and semi-dense patterns including lines and contact holes. The impact of isolated multilayer defects on the imaging of 22nm half-pitch dense line/contact and 33nm half-pitch semi-dense line has been studied, and the CD errors are calculated. The CD error, caused by the planar defect which is smoothed out during the multilayer deposition process, is found to be within ±10% of target values. This CD error can be compensated by adjusting the exposure dose or local pattern size. In contrast, the non-planar defect, which is not being smoothed in the multilayer surfaces, would lead to severe damages to the lithography performance.
With the continuous shrink of feature sizes, the 3D mask effects cannot be ignored in computational lithography. 3D mask effects inducing focus shift and scalar aberration like spherical aberration have been studied very well. To our knowledge, the polarization aberration (PA) including scalar aberration, retardance and diattenuation caused by 3D mask effects have not been paid attention to, which is very significant for computational lithography in advanced node. In this paper, we propose a novel approach to derive the PA induced by 3D mask effects from the diffraction frequency spectrum between the rigorous electromagnetic field model and the Kirchhoff model and express it as Jones matrix pupil. In addition, the physical decomposition of Jones matrix is adopted to obtain five physical properties of polarization aberration induced by 3D mask. Thus, the proposed method can fully, quantitatively, and clearly describe the PA induced by 3D mask.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
INSTITUTIONAL Select your institution to access the SPIE Digital Library.
PERSONAL Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.