Title :
A novel methodology of critical dimension statistical process control
Author :
Chen, C.P. ; Shyu, A. ; Liou, Pony ; Leu, R.Q. ; Huang, Kevin ; Lin, J.Y. ; Yang, T.H. ; Liu, H.C. ; Ting, M.I. ; Shih, Y.C.
Author_Institution :
FAB I, Macronix Corp., Taiwan
Abstract :
SPC (statistical process control) is a necessary tool for IC fabrication processing, especially when device dimensions are shrinking to 0.3 μm and beyond. Most fabs have real time SPC systems to help process engineers to control process quality. In addition to real time SPC systems, some other process control methodologies and indices may be necessary for enhancement of process control monitoring. We have applied a statistical program to analyze CD (critical dimension) variation and drift that mainly comes from machine and process induced variation. In order to respond in timely fashion to CD drift or shift caused by a machine, we generate a daily report using the concepts of “hypotheses testing” and “maximum shift” for the process engineer. In order to minimize process induced variation, we found that lens heating compensation, dynamic focusing and top antireflective coating (TARC) application are effective
Keywords :
antireflection coatings; compensation; integrated circuit measurement; integrated circuit yield; lenses; optical focusing; photolithography; process monitoring; size control; statistical process control; 0.35 micron; CD drift; CD shift; CD variation; IC fabrication; SPC; critical dimension statistical process control; critical dimension statistical process control methodology; device dimensions; dynamic focusing; hypotheses testing; lens heating compensation; machine induced variation; maximum shift; process control indices; process control methodologies; process control monitoring; process induced variation; process quality; real time SPC systems; statistical program; top antireflective coating; Condition monitoring; Control systems; Etching; Fabrication; Lenses; Probability; Process control; Real time systems; Statistical analysis; Testing;
Conference_Titel :
Statistical Metrology, 1998. 3rd International Workshop on
Conference_Location :
Honolulu, HI
Print_ISBN :
0-7803-4338-7
DOI :
10.1109/IWSTM.1998.729783
