Dresden 2006 – wissenschaftliches Programm

Bereiche | Tage | Auswahl | Suche | Downloads | Hilfe

DS: Dünne Schichten

DS 9: Functional thin films II

DS 9.1: Vortrag

Dienstag, 28. März 2006, 11:15–11:30, GER 37

Characterization of Chemical Bonding in Low-K Dielectric Materials for Interconnect Isolation: XAS and EELS Study — •P. Hoffmann¹, D. Schmeißer¹, F. Himpsel², H.-J. Engelmann³, E. Zschech³, H. Stegmann⁴, and J.D. Denlinger⁵ — ¹LS Angewandte Physik, BTU Cottbus, Conrad-Wachsmann-Allee 17, 03046 Cottbus — ²University of Wisconsin / Madison (USA) — ³AMD Saxony LLC & Co KG, Dresden (Germany) — ⁴Carl Zeiss NTS GmbH, Oberkochen (Germany) — ⁵ALS Berkley / California (USA)

The use of low dielectric constant materials in the on-chip interconnect process reduces interconnect delay, power dissipation and crosstalk noise. In CVD deposited organo-silicate glass (OSG) the substitution of oxygen in SiO₂ by methyl groups (-CH₃) reduces the permittivity significantly (from 4.0 in SiO₂ to 2.6-3.3 in the OSG). However, plasma processing removes C and H containing molecular groups. Therefore, compositional analysis and chemical bonding characterization of structured films with nanometer resolution is necessary. OSG thin films as-deposited and after plasma treatment are studied using XAS and EELS. In both techniques, the fine structure near the C1s edge allows to identify C-H, C-C, and C-O bonds. XAS spectra have been recorded for non-patterned films and EELS spectra for patterned structures. The chemical bonding is compared for as-deposited and plasma-treated low-k materials. The fluorescence and the electron yield recorded while XAS measurement are compared. Examination of the C 1s near-edge structures reveal a modified bonding of the remaining C atoms in the plasma-treated sample regions.