신호처리를 이용한 웨이퍼 다이싱 상태 모니터링

Wafer Dicing State Monitoring by Signal Processing

  • 발행 : 2000.05.01

초록

After the patterning and probe process of wafer have been achieved, the dicing process is necessary to separate chips from a wafer. The dicing process cuts a wafer to lengthwise and crosswise direction to make many chips by using narrow circular rotating diamond blade. But inferior goods are made under the influence of complex dicing environment such as blade, wafer, cutting water and cutting conditions. This paper describes a monitoring algorithm using feature extraction in order to find out an instant of vibration signal change when bad dicing appears. The algorithm is composed of two steps: feature extraction and decision. In the feature extraction, two features processed from vibration signal which is acquired by accelerometer attached on blade head are proposed. In the decision. a threshold method is adopted to classify the dicing process into normal and abnormal dicing. Experiment have been performed for GaAs semiconductor wafer. Based upon observation of the experimental results, the proposed scheme shown a good accuracy of classification performance by which the inferior goods decreased from 35.2% to 12.8%.

키워드

참고문헌

  1. H.T.Grimmelius, P.P.Meiler, et al., 'Three state-of-the-art methods for condition monitoring,' IEEE Trans. Ind. Elec., Vol. 42, No. 2, pp. 407-416, 1999 https://doi.org/10.1109/41.753780
  2. L.M.D.Owsley, L.E.Atlas, and G.D.Beranrd, 'Self-organizing feature maps and hidden markov models for machine-tool monitoring,' IEEE Trans. Sig. Process., Vol. 45, No. 11, pp. 2787-2797, 1997 https://doi.org/10.1109/78.650105
  3. S.Li, and M.A.Elbestawi, 'Tool condition monitoring in machining by fuzzy neural networks,' Journal of Dyn. Sys. Meas. and Control, Vol. 118, pp. 665-672, 1996
  4. Kwa, M. K., Denoyer, K. K., 'Dynamic Modelling and Vibration Suppression of a Slewing Structure Utilizing Piezoelectric Sensors and Actuators,' Journal of Sound and Vibration, Vol. 189, No. 1, pp. 13-31, 1996 https://doi.org/10.1006/jsvi.1996.0003
  5. 김명업, '웨이퍼가공기의 진동 해석 및 실험적 검증,' 한국과학기술원 석사학위 논문
  6. A.Hassui, A.E.Diniz, et al., 'Experimental evaluation on grinding wheel wear through vibration and acoustic emission,' Wear, Vol. 217, pp. 7-14, 1998 https://doi.org/10.1016/S0043-1648(98)00166-5