Failure mechanism analysis and process improvement on time-dependent dielectric breakdown of Cu/ultra-low-k dielectric based on complementary Raman and FTIR spectroscopy study

Time-dependent dielectric breakdown (TDDB) is one of the most important reliability issues in Cu/low-k technology development. With continuous technology scaling to nanometer scale, TDDB issue is further exacerbated. In this paper, two failure mechanisms were investigated: the Ta ions migration model and the line-edge-roughness (LER) model, which is rendering the observed TDDB failure. Complimentary Raman and FTIR spectroscopy were applied to investigate the dielectric bonding characteristics. Our experimental results revealed the TDDB degradation behavior of Cu/ultra-low-k interconnects, suggesting the intrinsic degradation of the ultra-low-k dielectric. No out-diffusion of Cu ions was observed in Cu/Ta/TaN/SiCOH structures. Extensive TEM analysis further verified the migration of Ta ions from the Ta/TaN barrier bi-layer into the ultra-low-k dielectrics. Based on the LER model analysis, a comparative study in both passing and failing die elaborates that the slopped trench/via profile affected the TDDB performance.

[1]  David J. Singh,et al.  Light scattering and surface plasmons on small spherical particles , 2014, Light: Science & Applications.

[2]  H. Misawa,et al.  Direct imaging of the near field and dynamics of surface plasmon resonance on gold nanostructures using photoemission electron microscopy , 2013, Light: Science & Applications.

[3]  Hongxing Xu,et al.  Remotely excited Raman optical activity using chiral plasmon propagation in Ag nanowires , 2013, Light: Science & Applications.

[4]  Fan Zhang,et al.  Evidence of ultra-low-k dielectric material degradation and nanostructure alteration of the Cu/ultra-low-k interconnects in time-dependent dielectric breakdown failure , 2013 .

[5]  J. W. McPherson,et al.  Time dependent dielectric breakdown physics - Models revisited , 2012, Microelectron. Reliab..

[6]  T. Wong.  Time Dependent Dielectric Breakdown in Copper Low-k Interconnects: Mechanisms and Reliability Models , 2012, Materials.

[7]  Joseph J. Talghader,et al.  Spectral selectivity in infrared thermal detection , 2012, Light: Science & Applications.

[8]  J. Bowers,et al.  Passive technologies for future large-scale photonic integrated circuits on silicon: polarization handling, light non-reciprocity and loss reduction , 2012, Light: Science & Applications.

[9]  P. Lam,et al.  Memory-enhanced noiseless cross-phase modulation , 2011, Light: Science & Applications.

[10]  C. Carteret,et al.  Vibrational properties of polysiloxanes: from dimer to oligomers and polymers. 1. Structural and vibrational properties of hexamethyldisiloxane (CH3)3SiOSi(CH3)3 , 2010 .

[11]  Sean W. King,et al.  Observation of space charge limited current by Cu ion drift in porous low-k/Cu interconnects , 2010 .

[12]  K. Gleason,et al.  Ultralow Dielectric Constant Tetravinyltetramethylcyclotetrasiloxane Films Deposited by Initiated Chemical Vapor Deposition (iCVD) , 2010 .

[13]  Chee Lip Gan,et al.  Effect of Ta migration from sidewall barrier on leakage current in Cu/SiOCH low-k dielectrics , 2009 .

[14]  W.D. van Driel,et al.  On Wire Failures in Microelectronic Packages , 2009, IEEE Transactions on Device and Materials Reliability.

[15]  R.W. Dutton,et al.  Design Methodology and Protection Strategy for ESD-CDM Robust Digital System Design in 90-nm and 130-nm Technologies , 2009, IEEE Transactions on Electron Devices.

[16]  F. Volpi,et al.  Copper-Line Topology Impact on the Reliability of SiOCH Low- $k$ for the 45-nm Technology Node and Beyond , 2008, IEEE Transactions on Device and Materials Reliability.

[17]  Fen Chen,et al.  Addressing Cu/Low-$k$ Dielectric TDDB-Reliability Challenges for Advanced CMOS Technologies , 2009, IEEE Transactions on Electron Devices.

[18]  P. Ho,et al.  Origin of dielectric loss induced by oxygen plasma on organo-silicate glass low-k dielectrics , 2008 .

[19]  Charge trapping at the low-k dielectric-silicon interface probed by the conductance and capacitance techniques , 2008 .

[20]  Fen Chen,et al.  Cu/low-k dielectric TDDB reliability issues for advanced CMOS technologies , 2008, Microelectron. Reliab..

[21]  P. Ho,et al.  Mechanistic study of plasma damage of low k dielectric surfaces , 2008 .

[22]  Ennis T. Ogawa,et al.  Reliability analysis method for low-k interconnect dielectrics breakdown in integrated circuits , 2005 .

[23]  J. Noguchi,et al.  Dominant factors in TDDB degradation of Cu interconnects , 2005, IEEE Transactions on Electron Devices.

[24]  A. Grill,et al.  Structure of low dielectric constant to extreme low dielectric constant SiCOH films: Fourier transform infrared spectroscopy characterization , 2003 .

[25]  R. Augur,et al.  Mechanism of reliability failure in Cu interconnects with ultralow-κ materials , 2003 .

[26]  Ahila Krishnamoorthy,et al.  Investigation of electrical conduction in carbon-doped silicon oxide using a voltage ramp method , 2003 .

[27]  L. Napolitano.  Materials , 1984, Science.