Nonlithographic coherent array of ultrafine particles on an irradiated material using Nd:YAG laser: influence of the laser fluence on the microstructure

Yuji Kawakami; Eiichi Ozawa

doi:10.1117/12.405710

6 November 2000 Nonlithographic coherent array of ultrafine particles on an irradiated material using Nd:YAG laser: influence of the laser fluence on the microstructure

Yuji Kawakami, Eiichi Ozawa

Author Affiliations +

Proceedings Volume 4088, First International Symposium on Laser Precision Microfabrication; (2000) https://doi.org/10.1117/12.405710
Event: First International Symposium on Laser Precision Microfabrication (LPM2000), 2000, Omiya, Saitama, Japan

Abstract

A non-lithographic coherent array of ultrafine tungsten particles (150-500 nm diameter) is self-assembly arranged around a laser-irradiated mark on a tungsten substrate. Single and poly-crystal tungsten substrates were irradiated by a Q-switched Nd:YAG laser under low pressure in an inert gas atmosphere. We studied the effect of the laser fluence on the morphology of the coherent arrays. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were used for these observations. The spacing of the coherent array increases with increasing laser fluence. For a 10.5 J/cm² irradiation, many droplets and peeling of the surfaces induced by rapid thermal expansion of the tungsten surface were observed. The recrystallizatoin texture on the surface was also confirmed by TEM observations. This suggests that the irradiated surface layer was partially recrystallized during laser irradiation. We concluded that coherent arrays are related to the laser fluence, the crystal surface structure, and the crystal growth. The recrystallization of the slightly melted tungsten on the top surface induced by the repeated laser irradiation plays a vital role in the formation of the array. If we can produce a coherent array of ultrafine tungsten particles with a higher aspect ratio, it may have potential applications for the emission cathodes of field emission displays (FED) and microelectronic devices.

Citation Download Citation

Yuji Kawakami and Eiichi Ozawa "Nonlithographic coherent array of ultrafine particles on an irradiated material using Nd:YAG laser: influence of the laser fluence on the microstructure", Proc. SPIE 4088, First International Symposium on Laser Precision Microfabrication, (6 November 2000); https://doi.org/10.1117/12.405710

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