Deposition Wet-Etching Deposition (DWD) Method for Polysilicon Gate Fill-In at Flash Memory

Chun Ling Chiang; C.M. Cheng; J.H. Liao; H.J. Lin; C.C. Yeh; J.Y. Hsieh; L.W. Yang; T.H. Yang; K.C. Chen; Chih Yuan Lu

doi:10.4028/www.scientific.net/SSP.187.49

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HomeSolid State PhenomenaSolid State Phenomena Vol. 187Deposition Wet-Etching Deposition (DWD) Method for...

Deposition Wet-Etching Deposition (DWD) Method for Polysilicon Gate Fill-In at Flash Memory

Abstract:

The present study aims at polysilicon material fill-in at re-entrant profile at flash memory product. The void was observed after polysilicon fill-in. In order to prevent the void formation, the multi-step process of deposition wet-etching deposition (DWD) method was evaluated. The DWD method is found to play beneficial roles in achieving void-free in the floating gate. The high concentration of NH₄OH in APM was choosing for wet etching solution. Scanned electron microscopy (SEM) and transmission electron microscopy (TEM) were employed to measure the polysilicon thickness and cross-section profile of device.

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Periodical:

Solid State Phenomena (Volume 187)

Pages:

49-52

DOI:

https://doi.org/10.4028/www.scientific.net/SSP.187.49

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Online since:

April 2012

Authors:

Chun Ling Chiang, C.M. Cheng, J.H. Liao, H.J. Lin, C.C. Yeh, J.Y. Hsieh, L.W. Yang, T.H. Yang, K.C. Chen, Chih Yuan Lu

Keywords:

APM, Polysilicon, Wet-Etching Deposition (DWD)

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References

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DOI: 10.4028/www.scientific.net/ssp.187.49

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