Influences of hydrogen in precursor Si films on excimer laser crystallization

Michiko Takahashi; Masakazu Saitoh; Kenkichi Suzuki; Kiyoshi Ogata

doi:10.1117/12.387542

7 June 2000 Influences of hydrogen in precursor Si films on excimer laser crystallization

Michiko Takahashi, Masakazu Saitoh, Kenkichi Suzuki, Kiyoshi Ogata

Proceedings Volume 3933, Laser Applications in Microelectronic and Optoelectronic Manufacturing V; (2000) https://doi.org/10.1117/12.387542
Event: Symposium on High-Power Lasers and Applications, 2000, San Jose, CA, United States

Abstract

The excimer laser crystallization (ELC) is a key technology of the low temperature polycrystalline silicon (LTP) thin film transistor (TFT) processes. The precursor Si for ELC is amorphous Si (a-Si) film, and hydrogen in the film has to be eliminated down to a certain concentration to prevent explosive evolution of hydrogen gas when excimer laser is irradiated. Hydrogen has been concerned only with respect to the effect for practical applications. This paper points out another aspect of hydrogen effect. There is correction between the bonding environments of precursor and polycrystalline Si (p-Si) structures produced through ELC process. The effect becomes explicit under 0.8 at percent of hydrogen conceits, and are clearly manifested in differences in lattice spacings of p-Si films. Variations of microscopic structure of the precursors are provided by three kinds of deposition methods, and dehydrogenation conditions. This paper also shows that transient boiling behaviors by the excimer laser discriminate prominently the differences among precursors. Although relationships between the behavior and microscopic structures are not clear, it gives an efficient measure for the bonding environment. It is also shown that the constants of p-Si is typically 10¹⁸/cm³ after multishot ELC process, and effusion of the hydrogen at one shot is rather small. This may lead to the inferences that hydrogen influence profoundly ELC process, and also contributes to preserve characteristic structure of the precursors.

Citation Download Citation

Michiko Takahashi, Masakazu Saitoh, Kenkichi Suzuki, and Kiyoshi Ogata "Influences of hydrogen in precursor Si films on excimer laser crystallization", Proc. SPIE 3933, Laser Applications in Microelectronic and Optoelectronic Manufacturing V, (7 June 2000); https://doi.org/10.1117/12.387542

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