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
Graphene-based Devices for More than Moore Applications
KTH, School of Information and Communication Technology (ICT), Integrated Devices and Circuits. (Information and Communication technology)ORCID iD: 0000-0003-4637-8001
2016 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

Moore's law has defined the semiconductor industry for the past 50 years. Devices continue to become smaller and increasingly integrated into the world around us. Beginning with personal computers, devices have become integrated into watches, phones, cars, clothing and tablets among other things. These devices have expanded in their functionality as well as their ability to communicate with each other through the internet. Further, devices have increasingly been required to have diverse of functionality. This combination of smaller devices coupled with diversification of device functionality has become known as more than Moore. In this thesis, more than Moore applications of graphene are explored in-depth.

Graphene was discovered experimentally in 2004 and since then has fueled tremendous research into its various potential applications. Graphene is a desirable candidate for many applications because of its impressive electronic and mechanical properties. It is stronger than steel, the thinnest known material, and has high electrical conductivity and mobility. In this thesis, the potentials of graphene are examined for pressure sensors, humidity sensors and transistors.

Through the course of this work, high sensitivity graphene pressure sensors are developed. These sensors are orders of magnitude more sensitive than competing technologies such as silicon nanowires and carbon nanotubes. Further, these devices are small and can be scaled aggressively.

Research into these pressure sensors is then expanded to an exploration of graphene's gas sensing properties -- culminating in a comprehensive investigation of graphene-based humidity sensors. These sensors have rapid response and recovery times over a wide humidity range. Further, these devices can be integrated into CMOS processes back end of the line.

In addition to CMOS Integration of these devices, a wafer scale fabrication process flow is established. Both humidity sensors and graphene-based transistors are successfully fabricated on wafer scale in a CMOS compatible process. This is an important step toward both industrialization of graphene as well as heterogeneous integration of graphene devices with diverse functionality. Furthermore, fabrication of graphene transistors on wafer scale provides a framework for the development of statistical analysis software tailored to graphene devices.

In summary, graphene-based pressure sensors, humidity sensors, and transistors are developed for potential more than Moore applications. Further, a wafer scale fabrication process flow is established which can incorporate graphene devices into CMOS compatible process flows back end of the line.

Place, publisher, year, edition, pages
KTH Royal Institute of Technology, 2016. , xxvi, 79 p.
Series
TRITA-ICT, 2016:17
Keyword [en]
Graphene, Humidity Sensor, Pressure Sensor, GFET, CMOS, BEOL, More than Moore, Integration, Statistics
National Category
Engineering and Technology Nano Technology
Identifiers
URN: urn:nbn:se:kth:diva-188134ISBN: 978-91-7729-024-7 (print)OAI: oai:DiVA.org:kth-188134DiVA: diva2:933541
Public defence
2016-08-26, Sal C, Isafjordsgatan 22, Electrum 229, 164-40, Kista, 10:00 (English)
Opponent
Supervisors
Note

QC 20160610

Available from: 2016-06-10 Created: 2016-06-06 Last updated: 2016-06-10Bibliographically approved
List of papers
1. Electromechanical Piezoresistive Sensing in Suspended Graphene Membranes
Open this publication in new window or tab >>Electromechanical Piezoresistive Sensing in Suspended Graphene Membranes
Show others...
2013 (English)In: Nano letters (Print), ISSN 1530-6984, E-ISSN 1530-6992, Vol. 13, no 7, 3237-3242 p.Article in journal (Refereed) Published
Abstract [en]

Monolayer graphene exhibits exceptional electronic and mechanical properties, making it a very promising material for nanoelectromechanical devices. Here, we conclusively demonstrate the piezoresistive effect in graphene in a nanoelectromechanical membrane configuration that provides direct electrical readout of pressure to strain transduction. This makes it highly relevant for an important class of nanoelectromechanical system (NEMS) transducers. This demonstration is consistent with our simulations and previously reported gauge factors and simulation values. The membrane in our experiment acts as a strain gauge independent of crystallographic orientation and allows for aggressive size scalability. When compared with conventional pressure sensors, the sensors have orders of magnitude higher sensitivity per unit area.

Keyword
Graphene, pressure sensor, piezoresistive effect, nanoelectromechanical systems (NEMS), MEMS
National Category
Nano Technology
Identifiers
urn:nbn:se:kth:diva-124556 (URN)10.1021/nl401352k (DOI)000321884300038 ()2-s2.0-84880160546 (Scopus ID)
Funder
EU, European Research Council, 228229 277879 307311
Note

QC 20130711

Available from: 2013-07-10 Created: 2013-07-10 Last updated: 2017-12-06Bibliographically approved
2. Pressure sensors based on suspended graphene membranes
Open this publication in new window or tab >>Pressure sensors based on suspended graphene membranes
Show others...
2013 (English)In: Solid-State Electronics, ISSN 0038-1101, E-ISSN 1879-2405, Vol. 88, 89-94 p.Article in journal (Refereed) Published
Abstract [en]

A novel pressure sensor based on a suspended graphene membrane is proposed. The sensing mechanism is explained based on tight binding calculations of strain-induced changes in the band structure. A CMOS compatible fabrication process is proposed and used to fabricate prototypes. Electrical measurement data demonstrates the feasibility of the approach, which has the advantage of not requiring a separate strain gauge, i.e. the strain gauge is integral part of the pressure sensor membrane. Hence, graphene membrane based pressure sensors can in principle be scaled quite aggressively in size.

Keyword
Graphene, Sensor, Pressure, Nanotechnology, NEMS and Nanoelectromechanical System, Piezoresistive
National Category
Engineering and Technology
Identifiers
urn:nbn:se:kth:diva-106199 (URN)10.1016/j.sse.2013.04.019 (DOI)000323865300017 ()2-s2.0-84884979426 (Scopus ID)
Funder
EU, European Research Council, 277879 307311 228229
Note

QC 20131002. Updated from accepted to published.

Available from: 2012-11-29 Created: 2012-11-29 Last updated: 2017-12-07Bibliographically approved
3. Strain engineering in suspended graphene devices for pressure sensor applications
Open this publication in new window or tab >>Strain engineering in suspended graphene devices for pressure sensor applications
Show others...
2012 (English)In: 2012 13th International Conference on Ultimate Integration on Silicon, ULIS 2012, IEEE , 2012, 21-24 p.Conference paper, Published paper (Refereed)
Abstract [en]

The present paper describes a device structure for controlling and measuring strain in graphene membranes. We propose to induce strain by creating a pressure difference between the inside and the outside of a cavity covered with a graphene membrane. The combination of tight-binding calculations and a COMSOL model predicts strain induced band gaps in graphene for certain conditions and provides a guideline for potential device layouts. Raman spectroscopy on fabricated devices indicates the feasibility of this approach. Ultimately, pressure-induced band structure changes could be detected electrically, suggesting an application as ultra-sensitive pressure sensors.

Place, publisher, year, edition, pages
IEEE, 2012
Keyword
device, graphene, membrane, Raman, strain
National Category
Electrical Engineering, Electronic Engineering, Information Engineering
Identifiers
urn:nbn:se:kth:diva-100023 (URN)10.1109/ULIS.2012.6193347 (DOI)2-s2.0-84861211414 (Scopus ID)978-146730191-6 (ISBN)
Conference
2012 13th International Conference on Ultimate Integration on Silicon, ULIS 2012; Grenoble;6 March 2012 through 7 March 2012
Funder
Swedish e‐Science Research CenterStandUp
Note

QC 20120806

Available from: 2012-08-06 Created: 2012-08-03 Last updated: 2016-06-10Bibliographically approved
4. Biaxial strain in suspended graphene membranes for piezoresistive sensing
Open this publication in new window or tab >>Biaxial strain in suspended graphene membranes for piezoresistive sensing
Show others...
2014 (English)In: 2014 IEEE 27th International Conference on Micro Electro Mechanical Systems (MEMS), IEEE , 2014, 1055-1058 p.Conference paper, Published paper (Refereed)
Abstract [en]

Pressure sensors based on suspended graphene membranes have shown extraordinary sensitivity for uniaxial strains, which originates from graphene's unique electrical and mechanical properties and thinness [1]. This work compares through both theory and experiment the effect of cavity shape and size on the sensitivity of piezoresistive pressure sensors based on suspended graphene membranes. Further, the paper analyzes the effect of both biaxial and uniaxial strain on the membranes. Previous studies examined uniaxial strain through the fabrication of long, rectangular cavities. The present work uses circular cavities of varying sizes in order to obtain data from biaxially strained graphene membranes.

Place, publisher, year, edition, pages
IEEE, 2014
Series
Proceedings of the IEEE International Conference on Micro Electro Mechanical Systems (MEMS), ISSN 1084-6999
Keyword
Membranes, MEMS, Pressure sensors, Strain, Biaxial strains, Electrical and mechanical properties, Piezoresistive pressure sensors, Piezoresistive sensing, Rectangular cavity, Strained graphene, Suspended graphene, Uni-axial strains, Graphene
National Category
Other Electrical Engineering, Electronic Engineering, Information Engineering
Identifiers
urn:nbn:se:kth:diva-145475 (URN)10.1109/MEMSYS.2014.6765826 (DOI)000352217500269 ()2-s2.0-84898971449 (Scopus ID)978-147993508-6 (ISBN)
Conference
27th IEEE International Conference on Micro Electro Mechanical Systems, MEMS 2014; San Francisco, CA; United States; 26 January 2014 through 30 January 2014
Note

QC 20140521

Available from: 2014-05-21 Created: 2014-05-21 Last updated: 2016-06-10Bibliographically approved
5. Resistive graphene humidity sensors with rapid and direct electrical readout
Open this publication in new window or tab >>Resistive graphene humidity sensors with rapid and direct electrical readout
Show others...
2015 (English)In: Nanoscale, ISSN 2040-3364, E-ISSN 2040-3372, Vol. 7, no 45, 19099-19109 p.Article in journal (Refereed) Published
Abstract [en]

We demonstrate humidity sensing using a change of the electrical resistance of single-layer chemical vapor deposited (CVD) graphene that is placed on top of a SiO2 layer on a Si wafer. To investigate the selectivity of the sensor towards the most common constituents in air, its signal response was characterized individually for water vapor (H2O), nitrogen (N-2), oxygen (O-2), and argon (Ar). In order to assess the humidity sensing effect for a range from 1% relative humidity (RH) to 96% RH, the devices were characterized both in a vacuum chamber and in a humidity chamber at atmospheric pressure. The measured response and recovery times of the graphene humidity sensors are on the order of several hundred milliseconds. Density functional theory simulations are employed to further investigate the sensitivity of the graphene devices towards water vapor. The interaction between the electrostatic dipole moment of the water and the impurity bands in the SiO(2)d substrate leads to electrostatic doping of the graphene layer. The proposed graphene sensor provides rapid response direct electrical readout and is compatible with back end of the line (BEOL) integration on top of CMOS-based integrated circuits.

Place, publisher, year, edition, pages
Royal Society of Chemistry, 2015
National Category
Condensed Matter Physics
Identifiers
urn:nbn:se:kth:diva-179618 (URN)10.1039/c5nr06038a (DOI)000364852500035 ()26523705 (PubMedID)2-s2.0-84947265250 (Scopus ID)
Funder
Swedish Research Council, E0616001 D0575901Knut and Alice Wallenberg FoundationSwedish Energy Agency
Note

QC 20160111

Available from: 2016-01-11 Created: 2015-12-17 Last updated: 2017-12-01Bibliographically approved
6. Large scale integration of graphene transistors for potential applications in the back end of the line
Open this publication in new window or tab >>Large scale integration of graphene transistors for potential applications in the back end of the line
Show others...
2015 (English)In: Solid-State Electronics, ISSN 0038-1101, E-ISSN 1879-2405, Vol. 108, 61-66 p.Article in journal (Refereed) Published
Abstract [en]

A chip to wafer scale, CMOS compatible method of graphene device fabrication has been established, which can be integrated into the back end of the line (BEOL) of conventional semiconductor process flows. In this paper, we present experimental results of graphene field effect transistors (GFETs) which were fabricated using this wafer scalable method. The carrier mobilities in these transistors reach up to several hundred cm(2) V-1 s(-1). Further, these devices exhibit current saturation regions similar to graphene devices fabricated using mechanical exfoliation. The overall performance of the GFETs can not yet compete with record values reported for devices based on mechanically exfoliated material. Nevertheless, this large scale approach is an important step towards reliability and variability studies as well as optimization of device aspects such as electrical contacts and dielectric interfaces with statistically relevant numbers of devices. It is also an important milestone towards introduting graphene into wafer scale process lines.

Keyword
Graphene, Transistor, Process integration, Wafer scale
National Category
Other Electrical Engineering, Electronic Engineering, Information Engineering
Identifiers
urn:nbn:se:kth:diva-166314 (URN)10.1016/j.sse.2014.12.014 (DOI)000353004400012 ()2-s2.0-84925599928 (Scopus ID)
Funder
EU, European Research Council, 228229, 307311
Note

QC 20150512

Available from: 2015-05-12 Created: 2015-05-07 Last updated: 2017-12-04Bibliographically approved
7. Wafer Scale Graphene Transfer for Back End of the Line Device Integration
Open this publication in new window or tab >>Wafer Scale Graphene Transfer for Back End of the Line Device Integration
Show others...
2014 (English)In: INT CONF ULTI INTEGR, ISSN 2330-5738, 29-32 p.Article in journal (Refereed) Published
Abstract [en]

We report on a wafer scale fabrication of graphene based field effect transistors (GFETs) for use in future radio frequency (RF) and sensor applications. The process is also almost entirely CMOS compatible and uses a scalable graphene transfer method that can be incorporated in standard CMOS back end of the line (BEOL) process flows. Such a process can be used to integrate high speed GFET devices and graphene sensors with silicon CMOS circuits.

Keyword
graphene, transistors, graphene transfer, wafer scale, GFET, more than Moore, Moore's Law
National Category
Electrical Engineering, Electronic Engineering, Information Engineering
Identifiers
urn:nbn:se:kth:diva-153862 (URN)10.1109/ULIS.2014.6813898 (DOI)000341731300008 ()2-s2.0-84901344723 (Scopus ID)
Conference
15th International Conference on Ultimate Integration on Silicon (ULIS), APR 07-09, 2014, Stockholm, SWEDEN
Note

QC 20141010

Available from: 2014-10-10 Created: 2014-10-09 Last updated: 2016-06-10Bibliographically approved

Open Access in DiVA

ADS_PhD_Thesis_2016(14296 kB)350 downloads
File information
File name FULLTEXT01.pdfFile size 14296 kBChecksum SHA-512
a764bcf98bfae328483a770203b2f1d37110d38a188ca31659786cdeb08c8b9f791fe4f28a29126f8f7ce5a87dd21ecda0b7c079d7632673c25184e868fd3c68
Type fulltextMimetype application/pdf
ADS_PhD_spik(181 kB)64 downloads
File information
File name FULLTEXT02.pdfFile size 181 kBChecksum SHA-512
6ef6f84cf3a07a57c6f47d0b4f6961d0485295c16b4e8b69a0e8422eb4e30c75dc2de09348c9e5979019d1fbc0e2dad470d7abffc835ebfea05edb225ebcd333
Type fulltextMimetype application/pdf

Search in DiVA

By author/editor
Smith, Anderson
By organisation
Integrated Devices and Circuits
Engineering and TechnologyNano Technology

Search outside of DiVA

GoogleGoogle Scholar
Total: 414 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

isbn
urn-nbn

Altmetric score

isbn
urn-nbn
Total: 1885 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