Journal of the Korean Physical Society

pISSN 0374-4884 eISSN 1976-8524


J. Korean Phy. Soc. 2009; 55(5(1)): 1780-1784

Published online November 14, 2009

Copyright © The Korean Physical Society.

The Optical and Mechanical Properties of Toluene-TEOS Hybrid Plasma-Polymer Thin Films Deposited by PECVD

Sang-Jin Cho, In-Seob Bae, Jin-Hyo Boo, Sungwoo Lee, Donggeun Jung


Toluene-TEOS hybrid plasma-polymer thin films were deposited on silicon(100) substrates by PECVD (Plasma Enhanced Chemical Vapor Deposition) with a homemade stainless steel vacuum chamber. Toluene and TEOS (tetraethoxysilane) were utilized as the organic and inorganic precursors with hydrogen gas for the toluene bubbler and argon gas for both the TEOS bubbler and as a carrier gas. To analyze the thermal, optical, and mechanical properties of the plasma polymerized thin films, hybrid plasma-polymer thin films were grown under conditions of various RF (radio frequency, 13.56 MHz) powers, bubbling ratios of TEOS and toluene precursors, and annealing temperatures. The thin films were analyzed by ellipsometry and FT-IR (Fourier Transform Infrared spectroscopy). The refractive indices changed under various RF powers, bubbling ratios of TEOS and toluene, and annealing temperatures. And the IR spectra showed that the hybrid plasma-polymer thin films have totally different chemical functionalities from liquid toluene and TEOS precursors, as well as the changing chemical functionalities of the thin films caused by various RF powers, bubbling gas ratio of TEOS and toluene and annealing temperature. Like as, the SiO peak intensity was increased with the increase of TEOS bubbling ratio and the 뻆H and the CO peak intensity was decreased with increasing the annealing temperature. From the FE-SEM (field emission scanning electron microscopy) results, the thickness of the thin films was determined before and after the annealing, with the thickness shrinkage (%) measured by SEM cross-sectional images. The MTS nano-indenter was used to measure the hardness and Young뭩 modulus and showed that both these values increased as deposition RF power increased; these values also changed with the bubbling ratio of TEOS and toluene and the annealing temperature.

Keywords: PECVD, dielectrics, low-k, optical and mechanical properties