Pore size evaluation of mesoporous organosilicate films by non-destructive X-ray reflectivity methods

• Published in: Japanese Journal of Applied Physics Vol. 54; no. 6S1; pp. 6 - 9
• Main Authors: Chien, Yun-San, Yeh, Yu-Shan, Chen, Yen-Song, Leu, Jih-Perng, Fu, Wei-En
• Format: Journal Article
• Language: English
• Published: The Japan Society of Applied Physics 01.06.2015
• ISSN: 0021-4922; 1347-4065
• DOI: 10.7567/JJAP.54.06FK03

200-nm-thick organosilicate films deposited by mixture of tetraethyl orthosilicate (TEOS) and methyltrimethoxysilane (MTMS) dissolving in different cetrimonium bromide (CTAB)/ethanol ratios were characterized in terms of pore size determination and its distribution. Under the toluene ambient, the pores would adsorb the gas hence elevating the whole film density. The X-ray reflectivity (XRR) equipped with mass flow control was utilized to detect the film density increasing. By fitting with Gaussian function and conversing with Kelvin s equation, the pore size was increased from 6.2 to 10.8 Å as the CTAB/ethanol ratio increasing to 0.075. It was attributed to the ethanol and CTAB enhanced the TEOS hollow droplets stability and dissolvability. As the CTAB/ethanol ratio is further increased, the pore size is reversely decreased, owing to the formation of solid microspheres. The non-destructive XRR measurement can evaluate the sub-nano pore sizes and its size distribution, which would fascinate the development and characterization of back-end of line process.