Characterization of Chemical Bonding in Low-K Dielectric Materials for Interconnect Isolation: A XAS and EELS Study

Springer Science and Business Media LLC - 2006
Patrick Hoffmann1, Dieter Schmeißer1, Hans-Juergen Engelmann2, Ehrenfried Zschech2, Heiko Stegmann3, F. J. Himpsel4, Jonathan D. Denlinger5
1Chair of Applied Physics II, Brandenburg Technical University of Cottbus, Cottbus, Germany
2AMD Saxony LLC & Co. KG, Dresden, Germany
3Carl Zeiss NTS GmbH, Oberkochen, Germany
4University of Wisconsin-Madison, Madison, USA
5Advanced Light Source, Berkekey, USA

Tóm tắt

AbstractThe use of low dielectric constant materials in the on-chip interconnect process reduces interconnect delay, power dissipation and crosstalk noise. To achieve the requirements of the ITRS for 2007-2009 minimal sidewall damage from etch, ash or cleans is required. In chemical vapor deposited (CVD) organo-silicate glass (OSG) which are used as intermetal dielectric (IMD) materials the substitution of oxygen in SiO2 by methyl groups (-CH3) reduces the permit-tivity significantly (from 4.0 in SiO2 to 2.6-3.3 in the OSG), since the electronic polarizability is lower for Si-C bonds than for Si-O bonds.However, plasma processing for resist stripping, trench etching and post-etch cleaning removes C and H containing molecular groups from the near-surface layer of OSG. Therefore, compositional analysis and chemical bonding characterization of structured IMD films with nanometer resolution is necessary for process optimization.OSG thin films as-deposited and after plasma treatment are studied using X-ray absorp-tion spectroscopy (XAS) and electron energy loss spectroscopy (EELS). In both techniques, the fine structure near the C1s absorption or energy loss edge, respectively, allows to identify C-H, C-C, and C-O bonds. This gives the opportunity to differentiate between individual low-k mate-rials and their modifications. The O1s signal is less selective to individual 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 Fluo-rescence Yield (FY) and the Total Electron Yield (TEY) recorded while XAS measurement are compared. Examination of the C 1s near-edge structures reveal a modified bonding of the re-maining C atoms in the plasma-treated sample regions.

Từ khóa


Tài liệu tham khảo

10.1016/S0167-9317(03)00438-6

9 Zschech E. , Stegmann H. , Hoffmann P. , Schmeisser D. , Potapov P. , Engelmann H.-J. , Chumakov D. , Geisler H. , Mater.Res.Soc.Proc., this volume.

10.1063/1.2063017

10.1021/la010237o

10.1063/1.1567460

10.1116/1.1651111

10.1016/j.mee.2005.07.016

10.1063/1.1929854

10.1016/j.mee.2005.03.058

10.1142/9789812775757_0006

10.1016/S0079-6700(00)00043-5

10.1038/nmat1291

Thông tin
Thông tin xuất bản

Springer Science and Business Media LLC

Thông tin tác giả