AVS 62nd International Symposium & Exhibition
    Electronic Materials and Processing Thursday Sessions
       Session EM-ThM

Paper EM-ThM10
The Effect of Vacuum Ultraviolet Irradiation on TDDB of Low-K Dielectrics using Synchrotron Radiation

Thursday, October 22, 2015, 11:00 am, Room 211C

Session: Interconnects II
Presenter: Dongfei Pei, University of Wisconsin-Madison
Authors: D. Pei, University of Wisconsin-Madison
M. Nichols, University of Wisconsin-Madison
S.W. King, Intel Corporation
J. Clarke, Intel Corporation
Y. Nishi, Stanford University
J.L. Shohet, University of Wisconsin-Madison
Correspondent: Click to Email
Time-dependent dielectric breakdown (TDDB) is a major concern for low-k dielectrics. Plasma processing, which involves ion bombardment and vacuum ultraviolet (VUV) irradiation, has been shown to cause TDDB degradation of low-k dielectrics. [i] Synchrotron radiation provides high-intensity monochromatic VUV photons with continuous variable wavelength. In this work, synchrotron irradiation between 5 and 20 eV was used to simulate VUV photon irradiation from a plasma without any particle flux. In this work porous organosilicate glass (SiCOH) was irradiated. A Cu / capping layer / SiCOH / titanium stack structure was fabricated so as to analyze the TDDB lifetime of both pristine and VUV-irradiated dielectrics. The photon flux varies with the wavelength so the irradiation time was chosen to produce the same amount of photon fluence at each photon energy. VUV photon energies larger than 7eV were found to create damage to porous SiCOH and cause TDDB degradation. With a photon fluence of 1016 photons/cm2, VUV photons with higher energies tend to cause more TDDB degradation.

This work was supported by the Semiconductor Research Corporation under Contract No. 2012-KJ-2359 and by the National Science Foundation under Grant CBET-1066231.

[i] M. T. Nichols, H. Sinha, C. A. Wiltbank, G. A. Antonelli,Y. Nishi, and J. L. Shohet, Appl. Phys. Lett 100, 112905 (2012)