Evaluation of near-surface microdefects in Czochralski-Si wafers after a CMOS process by an infrared interference method

Yutaka Kitagawara; Ken-ichi Aihara; Satoshi Oka; Takao Takenaka

doi:10.1117/12.221204

18 September 1995 Evaluation of near-surface microdefects in Czochralski-Si wafers after a CMOS process by an infrared interference method

Yutaka Kitagawara, Ken-ichi Aihara, Satoshi Oka, Takao Takenaka

Author Affiliations +

Proceedings Volume 2638, Optical Characterization Techniques for High-Performance Microelectronic Device Manufacturing II; (1995) https://doi.org/10.1117/12.221204
Event: Microelectronic Manufacturing '95, 1995, Austin, TX, United States

Abstract

Properties of near-sruface microdefects (NSMDs) 0-10 micrometers deep of Czochralski-Si wafers have been analyzed to understand how the as-grown crystal qualities are related to the NSMD characteristics after a CMOS thermal simulation. The microdefects are observed by an infrared interference method after a preliminary study to find the optimum condition for the high-sensitivity measurements. The results are compared with those by the infrared laser scattering tomography. Size distribution of the observed microdefects are analyzed to classify them into 'large-size' group and 'small-size' group. Comparing the NSMD characteristics after the CMOS process with those for the as-grown wafers, density of the relatively 'small- size' NSMDs is found to increase by the amount 10⁵-10⁶cm^-3 during the CMOS proces. The increase is especially notable for the wafers with low as-grown microdefect densities. In addition, these NSMD characteristics are shown to be related to the qualities of the MOS gate oxide films formed on the CMOS processed wafers. The time-zero dielectric breakdown characteristics are correlated with the NSMD density. On the other hand, the time-dependent dielectric breakdown characteristics are related to the amount of 'small- size' NSMDs generated during the CMOS process.

Citation Download Citation

Yutaka Kitagawara, Ken-ichi Aihara, Satoshi Oka, and Takao Takenaka "Evaluation of near-surface microdefects in Czochralski-Si wafers after a CMOS process by an infrared interference method", Proc. SPIE 2638, Optical Characterization Techniques for High-Performance Microelectronic Device Manufacturing II, (18 September 1995); https://doi.org/10.1117/12.221204

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available