Digitala Vetenskapliga Arkivet

Change search
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Growth and characterization of HfON thin films with the crystal structures of HfO2
Linköping University, Department of Physics, Chemistry and Biology, Plasma and Coating Physics .
2011 (English)Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
Abstract [en]

HfO2 is a popular replacement for SiO2 in modern CMOS technology. It is used as the gate dielectric layer isolating the transistor channel from the gate. For this application, certain material property demands need to be met, most importantly, a high static dielectric constant is desirable as this positively influences the effectiveness and reliability of the device. Previous theoretical calculations have found that this property varies with the crystal structure of HfO2; specifically, the tetragonal structure possesses the highest dielectric constant (~70 from theoretical calculations) out of all possible stable structures at atmospheric pressure, with the cubic phase a far second (~29, also calculated). Following the results from previous experimental work on the phase formation of sputtered HfO2, this study investigates the possibility of producing thin films of HfO2 with the cubic or tetragonal structure by the addition of nitrogen to a reactive sputtering process at various deposition temperatures. Also, a new physical vapor deposition method known as High Power Impulse Magnetron Sputtering (HiPIMS) is employed for its reported deposition stability in the transition zone of metal-oxide compounds and increased deposition rate. Structural characterization of the produced films shows that films deposited at room temperature with a low N content (~6 at%) are mainly composed of amorphous HfO2 with mixed crystallization into t-HfO2 and c-HfO2, while pure HfO2 is found to be composed of amorphous HfO2 with signs of crystallization into m-HfO2. At 400o C deposition temperature, the crystalline quality is enhanced and the structure of N incorporated HfO2 is found to be c-HfO2 only, due to further ordering of atoms in the crystal lattice. Optical and dielectric characterization revealed films with low N incorporation (< 6 at%) to be insulating while these became conductive for higher N contents. For the insulating films, a trend of increasing static dielectric constant with increasing N incorporation is found.

Place, publisher, year, edition, pages
2011. , p. 58
Keywords [en]
hafnium dioxide, thin films, gate dielectric, nitrogen incorporation, dielectric constant, crystal structure, HIPIMS, magnetron sputtering
National Category
Condensed Matter Physics
Identifiers
URN: urn:nbn:se:liu:diva-71620ISRN: LITH-IFM-A-EX--11/2531—SEOAI: oai:DiVA.org:liu-71620DiVA, id: diva2:451659
Subject / course
Material Physics
Presentation
2011-06-08, Röntgen P404, Physics Building, Linköping University, SE-581 83, Linköping, 14:00
Uppsok
Physics, Chemistry, Mathematics
Supervisors
Examiners
Available from: 2011-10-26 Created: 2011-10-26 Last updated: 2011-11-29Bibliographically approved

Open Access in DiVA

Growth and characterization of HfON thin films with the crystal structures of HfO2(3419 kB)1420 downloads
File information
File name FULLTEXT01.pdfFile size 3419 kBChecksum SHA-512
7635e21bf2a41dd75b533a6ee6bfd62fff761780e284deb4317dadb47ac5e30c2b17d439c10364210d07258a568b26127891b77158ffd562b3920d1164ccf3d3
Type fulltextMimetype application/pdf

By organisation
Plasma and Coating Physics
Condensed Matter Physics

Search outside of DiVA

GoogleGoogle Scholar
Total: 1420 downloads
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

urn-nbn

Altmetric score

urn-nbn
Total: 537 hits
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf