skip to main content

Title: Measurements of Schottky barrier at the low-k SiOC:H/Cu interface using vacuum ultraviolet photoemission spectroscopy

The band alignment between copper interconnects and their low-k interlayer dielectrics is critical to understanding the fundamental mechanisms involved in electrical leakage in low-k/Cu interconnects. In this work, vacuum-ultraviolet (VUV) photoemission spectroscopy is utilized to determine the potential of the Schottky barrier present at low-k a-SiOC:H/Cu interfaces. By examining the photoemission spectra before and after VUV exposure of a low-k a-SiOC:H (k = 3.3) thin film fabricated by plasma-enhanced chemical-vapor deposition on a polished Cu substrate, it was found that photons with energies of 4.9 eV or greater can deplete accumulated charge in a-SiOC:H films, while VUV photons with energies of 4.7 eV or less, did not have this effect. These critical values were identified to relate the electric potential of the interface barrier between the a-SiOC:H and the Cu layers. Using this method, the Schottky barrier at the low-k a-SiOC:H (k = 3.3)/Cu interface was determined to be 4.8 ± 0.1 eV.
Authors:
; ; ;  [1] ;  [2] ; ; ;  [3] ;  [4]
  1. Plasma Processing and Technology Laboratory and Department of Electrical and Computer Engineering, University of Wisconsin-Madison, Madison, Wisconsin 53706 (United States)
  2. Logic Technology Development, Intel Corporation, Hillsboro, Oregon 97124 (United States)
  3. National Synchrotron Radiation Research Center, Hsinchu 30076, Taiwan (China)
  4. Department of Electrical Engineering, Stanford University, Stanford, California 94305 (United States)
Publication Date:
OSTI Identifier:
22486201
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 107; Journal Issue: 23; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; COPPER; DIELECTRIC MATERIALS; ELECTRIC POTENTIAL; FAR ULTRAVIOLET RADIATION; PHOTOELECTRON SPECTROSCOPY; PHOTOEMISSION; SPECTRA; SUBSTRATES; THIN FILMS