Laboratory X-ray Microscopy of 3D Nanostructures in the Hard X-ray Regime Enabled by a Combination of Multilayer X-ray Optics

Publikation: Beitrag in FachzeitschriftForschungsartikelBeigetragenBegutachtung

Beitragende

  • Bartlomiej Lechowski - , deepXscan GmbH (Autor:in)
  • Kristina Kutukova - , deepXscan GmbH (Autor:in)
  • Joerg Grenzer - , deepXscan GmbH (Autor:in)
  • Iuliana Panchenko - , Professur für Aufbau- und Verbindungstechnik der Elektronik, Fraunhofer Institute for Reliability and Microintegration - All Silicon System Integration Dresden (IZM - ASSID) (Autor:in)
  • Peter Krueger - , Fraunhofer-Institut für Keramische Technologien und Systeme (Autor:in)
  • Andre Clausner - , Fraunhofer-Institut für Keramische Technologien und Systeme (Autor:in)
  • Ehrenfried Zschech - , deepXscan GmbH, Brandenburgische Technische Universität Cottbus-Senftenberg (Autor:in)

Abstract

High-resolution imaging of buried metal interconnect structures in advanced microelectronic products with full-field X-ray microscopy is demonstrated in the hard X-ray regime, i.e., at photon energies > 10 keV. The combination of two multilayer optics—a side-by-side Montel (or nested Kirkpatrick–Baez) condenser optic and a high aspect-ratio multilayer Laue lens—results in an asymmetric optical path in the transmission X-ray microscope. This optics arrangement allows the imaging of 3D nanostructures in opaque objects at a photon energy of 24.2 keV (In-Kα X-ray line). Using a Siemens star test pattern with a minimal feature size of 150 nm, it was proven that features < 150 nm can be resolved. In-Kα radiation is generated from a Ga-In alloy target using a laboratory X-ray source that employs the liquid-metal-jet technology. Since the penetration depth of X-rays into the samples is significantly larger compared to 8 keV photons used in state-of-the-art laboratory X-ray microscopes (Cu-Kα radiation), 3D-nanopattered materials and structures can be imaged nondestructively in mm to cm thick samples. This means that destructive de-processing, thinning or cross-sectioning of the samples are not needed for the visualization of interconnect structures in microelectronic products manufactured using advanced packaging technologies. The application of laboratory transmission X-ray microscopy in the hard X-ray regime is demonstrated for Cu/Cu6Sn5/Cu microbump interconnects fabricated using solid–liquid interdiffusion (SLID) bonding.

Details

OriginalspracheEnglisch
Aufsatznummer233
FachzeitschriftNanomaterials
Jahrgang14
Ausgabenummer2
PublikationsstatusVeröffentlicht - Jan. 2024
Peer-Review-StatusJa

Externe IDs

Scopus 85183632671
ORCID /0000-0001-8576-7611/work/165877218

Schlagworte

Schlagwörter

  • X-ray microscopy, advanced packaging, high-resolution radiography, nanostructure