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Title: CMP Control of Multi-Layer Inter-Layer Dielectrics (ILD) using X-ray Reflectivity

Abstract

Thin sacrificial films are used as cap layer in the back-end semiconductor processing for protecting the bulk porous inter-layer low-k dielectric during the CMP process. The existing optical measurement techniques struggle to separate these thin films from the bulk low-k due to very similar optical coefficients. Glancing angle x-ray reflectivity is well suited for separation of thin sacrificial film and bulk dielectric film as x-ray reflectivity depends strongly on changes in electron densities for two materials. This paper discusses the x-ray reflectivity technique and its applications for measurement of low-k stack and sacrificial oxide post CMP.

Authors:
 [1];  [2];  [1]; ; ;  [3]
  1. Rohm and Haas Electronic Materials, 3804 E. Watkins Street, Phoenix, AZ 85034 (United States)
  2. (United States)
  3. Jordan Valley Semiconductors, Inc., 8601 Cross Park Drive 200, Austin, TX 78754 (Jordan)
Publication Date:
OSTI Identifier:
21032715
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Conference Proceedings; Journal Volume: 931; Journal Issue: 1; Conference: 2007 international conference on frontiers of characterization and metrology, Gaithersburg, MD (United States), 27-29 Mar 2007; Other Information: DOI: 10.1063/1.2799373; (c) 2007 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; DIELECTRIC MATERIALS; ELECTRON DENSITY; LAYERS; MECHANICAL POLISHING; NANOSTRUCTURES; OXIDES; POROUS MATERIALS; PROCESSING; REFLECTION; REFLECTIVITY; SEMICONDUCTOR MATERIALS; THIN FILMS; X-RAY DIFFRACTION

Citation Formats

Bryant, Ross E., Current Affiliation: Particle Measuring Systems, 5475 Airport Blvd, Boulder, CO 80301, Porter, Hethel, Gallegos, Jesus, O'Dell, Jeremy, and Agnihotri, Dileep. CMP Control of Multi-Layer Inter-Layer Dielectrics (ILD) using X-ray Reflectivity. United States: N. p., 2007. Web. doi:10.1063/1.2799373.
Bryant, Ross E., Current Affiliation: Particle Measuring Systems, 5475 Airport Blvd, Boulder, CO 80301, Porter, Hethel, Gallegos, Jesus, O'Dell, Jeremy, & Agnihotri, Dileep. CMP Control of Multi-Layer Inter-Layer Dielectrics (ILD) using X-ray Reflectivity. United States. doi:10.1063/1.2799373.
Bryant, Ross E., Current Affiliation: Particle Measuring Systems, 5475 Airport Blvd, Boulder, CO 80301, Porter, Hethel, Gallegos, Jesus, O'Dell, Jeremy, and Agnihotri, Dileep. 2007. "CMP Control of Multi-Layer Inter-Layer Dielectrics (ILD) using X-ray Reflectivity". United States. doi:10.1063/1.2799373.
@article{osti_21032715,
title = {CMP Control of Multi-Layer Inter-Layer Dielectrics (ILD) using X-ray Reflectivity},
author = {Bryant, Ross E. and Current Affiliation: Particle Measuring Systems, 5475 Airport Blvd, Boulder, CO 80301 and Porter, Hethel and Gallegos, Jesus and O'Dell, Jeremy and Agnihotri, Dileep},
abstractNote = {Thin sacrificial films are used as cap layer in the back-end semiconductor processing for protecting the bulk porous inter-layer low-k dielectric during the CMP process. The existing optical measurement techniques struggle to separate these thin films from the bulk low-k due to very similar optical coefficients. Glancing angle x-ray reflectivity is well suited for separation of thin sacrificial film and bulk dielectric film as x-ray reflectivity depends strongly on changes in electron densities for two materials. This paper discusses the x-ray reflectivity technique and its applications for measurement of low-k stack and sacrificial oxide post CMP.},
doi = {10.1063/1.2799373},
journal = {AIP Conference Proceedings},
number = 1,
volume = 931,
place = {United States},
year = 2007,
month = 9
}
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