Tomography experiment of an integrated circuit specimen using 3 MeV electrons in the transmission electron microscope.

The possibility of utilizing high-energy electron tomography to characterize the micron-scale three dimensional (3D) structures of integrated circuits has been demonstrated experimentally. First, electron transmission through a tilted SiO(2) film was measured with an ultrahigh-voltage electron microscope (ultra-HVEM) and analyzed from the point of view of elastic scattering of electrons, showing that linear attenuation of the logarithmic electron transmission still holds valid for effective specimen thicknesses up to 5 microm under 2 MV accelerating voltages. Electron tomography of a micron-order thick integrated circuit specimen including the Cu/via interconnect was then tried with 3 MeV electrons in the ultra-HVEM. Serial projection images of the specimen tilted at different angles over the range of +/-90 degrees were acquired, and 3D reconstruction was performed with the images by means of the IMOD software package. Consequently, the 3D structures of the Cu lines, via and void, were revealed by cross sections and surface rendering.

[1]  J R Kremer,et al.  Computer visualization of three-dimensional image data using IMOD. , 1996, Journal of structural biology.

[2]  Hong Zhang.  Transmission electron microscopy for the semi-conductor industry. , 2002, Micron.

[3]  Zachary H. Levine,et al.  Submicron imaging of buried integrated circuit structures using scanning confocal electron microscopy , 2002 .

[4]  Z. Levine,et al.  Parallax measurements of integrated circuit interconnects using a scanning transmission electron microscope , 2003 .

[5]  S Jonić,et al.  Spectral signal-to-noise ratio and resolution assessment of 3D reconstructions. , 2005, Journal of structural biology.

[6]  Takashi Aoyama,et al.  Developments of new concept analytical instruments for failure analyses of sub-100 nm devices , 2001, Microelectron. Reliab..

[7]  David C. Joy,et al.  Monte Carlo Modeling for Electron Microscopy and Microanalysis , 1995 .

[8]  P. Midgley,et al.  3D electron microscopy in the physical sciences: the development of Z-contrast and EFTEM tomography. , 2003, Ultramicroscopy.

[10]  Z. Levine.  Tomography in the multiple scattering regime of the scanning transmission electron microscope , 2003 .

[11]  A. Takaoka,et al.  A 360°-tilt specimen holder for electron tomography in an ultrahigh-voltage electron microscope , 1998 .

[12]  Leslie J. Allen,et al.  Three-dimensional imaging of individual hafnium atoms inside a semiconductor device , 2005 .

[13]  D. P. Vallett.  Failure analysis requirements for nanoelectronics , 2002 .

[14]  A. Takaoka,et al.  Measuring the top–bottom effect of a tilted thick specimen in an ultrahigh-voltage electron microscope , 2005 .

[15]  K. Tu.  Recent advances on electromigration in very-large-scale-integration of interconnects , 2003 .

[16]  Robert M. Lewitt,et al.  Image processing approaches to biological three‐dimensional electron microscopy , 2000 .

[17]  Zachary H. Levine.  The boundary of x-ray and electron tomography , 2005, IS&T/SPIE Electronic Imaging.

[18]  David B. Williams,et al.  Transmission Electron Microscopy , 1996 .

[19]  Akio Takaoka,et al.  Development of a new 3 MV ultra-high voltage electron microscope at Osaka University , 1997 .

[20]  Bruce F. McEwen,et al.  Three-dimensional tomographic reconstruction in high voltage electron microscopy , 1987 .

[21]  A. Verkleij,et al.  Three-Dimensional Transmission Electron Microscopy: A Novel Imaging and Characterization Technique with Nanometer Scale Resolution for Materials Science , 2000 .

[22]  M. Iwaki,et al.  Three-dimensional STEM for observing nanostructures. , 2001, Journal of electron microscopy.

[23]  Zachary H. Levine,et al.  Theory of bright-field scanning transmission electron microscopy for tomography , 2005 .

[24]  P. Midgley,et al.  The chemical application of high-resolution electron tomography: bright field or dark field? , 2004, Angewandte Chemie.