학술논문
Optimization of post N/sub 2/ treatment & USG cap layer to improve tungsten peeling defects for deep sub-micron device yield improvement
Document Type
Conference
Author
Source
Proceedings of ISSM2000. Ninth International Symposium on Semiconductor Manufacturing (IEEE Cat. No.00CH37130) Semiconductor manufacturing Semiconductor Manufacturing, 2000. Proceedings of ISSM 2000. The Ninth International Symposium on. :438-441 2000
Subject
Language
ISSN
1523-553X
Abstract
Integration issue of W-plug peeling from fluorinated silica glass (FSG) in deep sub-micron IMD application was investigated in this study. Tungsten would peel off immediately during post CMP N/sub 2/ treatment in-situ running with USG cap layer deposition after W-plug deposition. Separating or optimizing post-CMP N/sub 2/ treatment and cap layer would solve this peeling issue. The key points of peeling were the bias power of N/sub 2/ treatment and initial USG cap temperature in the HDP-CVD chamber. TOF-SIMS analysis revealed that higher bias power and longer treatment time lead to more fluorine distribution on the USG cap layer surface, which may cause non-Si-F bonding fluorine to react with subsequent Ti/TiN/W metal layer. FTIR spectra also showed that low bias power, adding an extra cooling step before substantial in-situ cap layer deposition or ex-situ cap would increase fluorine stability in FSG/USG interface.