Queue Time Sensitivity Analysis Methodology

Abstract:

Queue time (QT) between consecutive process-steps is one of the factors affecting the quality of current products in semiconductors industry. Identification of process steps with queue time sensitivity is not an easy and quick analysis, and it requires a high number of lots. An effective tool for a quick identification of sensitivity of a specific operation to a queue time was developed at Micron Israel and it is applied on production material. The algorithm calculates the average absolute delta of responses between consecutive step QTs, where a minimal value is accepted in steps with a linear correlation between the QT and the response. This calculation results in a snap-shot of the impact of QT for specific responses, or failures modes, for the entire production line, where the step with minimal value of this parameter is easily detected. This algorithm was used on production material and indeed helped to detect a new QT dependency in specific process steps. The Queue Time Sensitivity Analysis (QTSA) algorithm is a novel methodology to detect correlation of QT in a single process step to a certain electrical EOL failure. It can be easily implemented in a fabrication site by the IT team. QTSA methodology is very efficient in detecting QT related issues and it can be used both in routine mode on baseline material and during significant elevation in EOL or in-line failures.

• Periodical: Solid State Phenomena (Volumes 205-206)
• Pages: 376-379
• DOI: https://doi.org/10.4028/www.scientific.net/SSP.205-206.376
• Online since: October 2013
• Authors: Alex Freilikhman, Rotem Drori, Yakov Shor
• Keywords: Algorithm (GA), Correlation, Die Yield, Methodology, Process Step, Queue Time

References

[1] P. Gupta, & E. Papadopoulou, Yield analysis and optimization. The Handbook of Algorithms for VLSI Physical Design Automation.

[2] K. Schmidt, & O. Rose, Queue time and x-factor characteristics for semiconductor manufacturing with small lot sizes. Paper presented at the Automation Science and Engineering, 2007. CASE 2007. IEEE International Conference on, pp.1069-1074.

DOI: 10.1109/coase.2007.4341825

[3] Y. Lee, C. Chen, & C. Wu, Reaction chain of process queue time quality control. Paper presented at the Semiconductor Manufacturing, 2005. ISSM 2005, IEEE International Symposium on, pp.47-50.

DOI: 10.1109/issm.2005.1513293

[4] Y. A. Wahab, A. F. Ahmad, & Z. Awang, Queue time impact on defectively at post copper barrier seed, electrochemical plating, anneals and chemical mechanical polishing. Paper presented at the Semiconductor Electronics, 2006. ICSE'06. IEEE International Conference on, pp.938-943.

DOI: 10.1109/smelec.2006.380777

[5] P. Haumesser, A. Roule, S. Maîtrejean, & G. Passemard, (2005). Seed enhancement: A bridging technology. Future Fab Intl, 19, 81-83.