uu.seUppsala University Publications
Change search
ReferencesLink to record
Permanent link

Direct link
Time-of-Flight Characterization of Single-crystalline CVD Diamond with Different Surface Passivation Layers
Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Electricity.
2011 (English)Conference paper (Refereed)
Place, publisher, year, edition, pages
National Category
Engineering and Technology
URN: urn:nbn:se:uu:diva-229755DOI: 10.1557/opl.2011.311OAI: oai:DiVA.org:uu-229755DiVA: diva2:737435
MRS fall meeting 2010.
Available from: 2014-08-12 Created: 2014-08-12 Last updated: 2016-04-20
In thesis
1. Diamond Based Electronics and Valleytronics: An experimental study
Open this publication in new window or tab >>Diamond Based Electronics and Valleytronics: An experimental study
2014 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

Diamond is a promising semiconductor material for high power, high voltage, high temperature and high frequency applications due to its remarkable material properties: it has the highest thermal conductivity, it is the hardest material, chemically inert, radiation hard and has the widest transparency in the electromagnetic spectrum. It also exhibits excellent electrical properties like high breakdown field, high mobilities and a wide bandgap.  Hence, it may find applications in extreme conditions out of reach for conventional semiconductor materials, e.g. in high power density systems, high temperature conditions, automotive and aerospace industries, and space applications. 


With the recent progress in the growth of high purity single-crystalline CVD diamond, the realization of electronic devices is now possible. Natural and HPHT diamonds inevitably have too high a concentration of impurities and defects for electrical applications. To develop efficient electronic devices based on diamond, it is crucial to understand charge transport properties. Time-of-flight is one of the most powerful methods used to study charge transport properties like mobility, drift velocity and charge collection efficiency in highly resistive semiconductors, such as diamond. For commercial diamond devices to become a reality, it is necessary to have an effective surface passivation since the passivation determines the ability of a device to withstand high surface electric fields. Surface passivation studies on intrinsic SC-CVD diamond using materials like silicon oxide, silicon nitride and high-k materials have been conducted and observations reveal an increase in measured hole mobilities. Planar MOS capacitor structures form the basic building block of MOSFETs. Consequently, the understanding of MOS structures is crucial to make MOSFETs based on diamond. Planar MOS structures with aluminum oxide as gate dielectric were fabricated on boron doped diamond. The phenomenon of inversion was observed for the first time in diamond. In addition, low temperature hole transport in the range of 10-80 K has been investigated and the results are used to identify the type of scattering mechanisms affecting hole transport at these temperatures.

To utilize the potential of diamonds properties and with diamond being the hardest and most chemically inert material, new processing technologies are needed to produce devices for electrical, optical or mechanical applications. Etching of diamond is one of the important processing steps required to make devices. Achieving an isotropic etch with a high etch rate is a challenge. Semi-isotropic etch profiles with smooth surfaces were obtained by using anisotropic etching technique by placing diamond samples in a Faraday cage and etch rates of approximately 80 nm/min were achieved.

Valleytronics, which is a novel concept to encode information based on the valley quantum number of electrons has been investigated for the first time in diamond. Valley-polarized electrons with the longest relaxation time ever recorded in any material (300 ns) were observed. This is a first step towards demonstrating valleytronic devices.

Place, publisher, year, edition, pages
Uppsala: Acta Universitatis Upsaliensis, 2014. 61 p.
Digital Comprehensive Summaries of Uppsala Dissertations from the Faculty of Science and Technology, ISSN 1651-6214 ; 1163
National Category
Engineering and Technology
Research subject
Engineering Science with specialization in Science of Electricity
urn:nbn:se:uu:diva-229948 (URN)978-91-554-8999-1 (ISBN)
Public defence
2014-09-29, Polhemsalen, Ångström laboratory, Uppsala, 13:15 (English)
Available from: 2014-09-05 Created: 2014-08-18 Last updated: 2014-12-02

Open Access in DiVA

No full text

Other links

Publisher's full text

Search in DiVA

By author/editor
Kovi, Kiran Kumar
By organisation
Engineering and Technology

Search outside of DiVA

GoogleGoogle Scholar

Altmetric score

Total: 217 hits
ReferencesLink to record
Permanent link

Direct link