Michael Andersson, Samina Bidmeshkipour,

Marlene Bonmann, Andrei Vorobiev, Jan Stake

Terahertz and Millimetre Wave Laboratory

Department of Microtechnology and Nanoscience

Chalmers University of Technology

Göteborg, Sweden

SSF project

Carbon Based High Speed 3D GaN

Electronics System

Consortium meeting, 2015-03-24

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Tuesday, Mar 24, 2015

Chalmers, Göteborg

10:00 – 10:15

General discussion and status of the project

- Update of deliverables and timeline

- Review meeting preparation (May 13)Johan Liu

10:15 – 11:15

WP1 Presentations

- Objectives

- Progress and main results

- Schedule of deliverables

- Future plan

Johan Liu

11:15 – 12: 15

WP2 Presentations

- Objectives

- Progress and main results

- Schedule of deliverables

- Future plan

Johan Liu

12:15 – 13: 15 Lunch

13:15 – 14: 15

WP3 Presentations

- Objectives

- Progress and main results

- Schedule of deliverables

- Future plan

Zhibin Zhang

14:15 – 14: 30 Coffee break

14:30 – 15: 30

WP4 Presentations

- Objectives

- Progress and main results

- Schedule of deliverables

- Future plan

Jan Stake

15:30 – 16: 30

WP5 Presentations

- Objectives

- Progress and main results

- Schedule of deliverables

- Future plan

Per Hyldgaard

16: 30 End of meeting

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Objectives

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Objectives

main objective:

demonstrating a complete graphene radio (LNA + mixer) with significantly improved microwave

performance by finding ways to open up for a band gap in graphene.

4

Progress since last meeting, 2015-02-20

Development of transfer process

Bubbling transfer, CVD graphene by Graphenea (coverage: 98%)

coverage: 58%

processed imageoptical image

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Frame assisted H2 bubbling transfer

Adopted from M. Tanzid, Thesis for Master of Science, Chalmers, 2013.

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Progress since last meeting, 2015-02-20

Effect of coverage (80-85%) on device performance

Reduced reproducibility/yield and device performance

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Copper APS etching transfer

Progress since last meeting, 2015-02-20

Ammonium persulfate

(NH4)2S2O8

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Progress since last meeting, 2015-02-20

Development of transfer process

Copper APS etching transfer, CVD graphene by Graphenea

coverage: 99.9%

processed imageoptical image

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Progress since last meeting, 2015-02-20

Effect of CVD growth

CNT CVD "Black Magic”(MC2), copper APS etching transfer

coverage: 65.0%

processed imageoptical image

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Progress since last meeting, 2015-02-20

Effect of CVD growth

CVD graphene by Graphenea, copper APS etching transfer

coverage: 99.9%

processed imageoptical image

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Deliverables/MilestonesGroups Tasks Deliverables/Milestones

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Ferroelectric materials for higher on/off ratio

• G-FETs cannot be turned off effectively due to the absence of a band gap, leading to an on/off

current ratio typically around 5. A band gap up to a few hundred meVs can be created by the

perpendicular E-field in bilayer graphene.

• Bilayer graphene on ferroelectrics with spontaneous polarization field sufficiently strong for

inducing bandgap.

Implementation

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G-FET on LiNbO3 (first demonstration)

• These are DUT microwave performance (current gain and power gain).

• We expect much higher intrinsic parameters (since contact resistance 3 kµm).

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Last meeting notes

SSF project – Carbon 3D GaN

Teleconf meeting notes 20150220

Participants: Johan Liu, Aaron Zhang, Murali Murugesan, Josef Hansson, Wayne Mu, Di

Jiang, Michael Sun, Yifeng Fu, Andrei Vorobiev, Michael Andersson, Subimal Majee

Meeting notes:

1. 4 deliverables will be submitted 3 months later, i.e. May 2015, one from each partner.

2. Each partner updated task progress by PPT. Per’s PPT was presented, questions

remained and Johan will set up an individual meeting.

3. JL sent second version of graphene ink to ZZ. Flake size of >1 μm and graphene flake

precipitation were found. New raw material, further exfoliation and new additives will

be considered for improvement.

4. JL will send another nano-particle based ink to ZZ for inkjet printing test.

5. Graphene exfoliation by shear mixing in UU is ongoing in parallel to prepare the

graphene ink.

6. PHD student is already recruited in this project in JS group. Master project is also

started.

7. Requirements on GaN substrate quality is dependent on integration strategy, i.e. direct

device fabrication on GaN substrate or fabrication of devices on HR Si and afterwards

integration onto GaN carrier? BN buffer layer is needed or not? Johan will set up

individual meeting for discussion in more detail.

8. Andrei please send presentation in PPT format to JL.

9. Publications are highly recommended to be updated in future meetings.

10. Next consortium meeting will be held in Chalmers on March 24. Project progress and

preparation for review meeting will be discussed. Collaborations in the consortium

should be highlighted. A rehearsal for the review will be arranged. Agenda will be

sent out before that. 15

Publications

1. M. A. Andersson, A. Vorobiev, S. Gevorgian, and J. Stake, Extraction of carrier

transport properties in graphene from microwave measurements, Proceedings of the

44th European Microwave Conference (EuMC), p. 359 – 362, (2014).

2. A. Zak, M. A. Andersson, M. Bauer, J. Matukas, A. Lisauskas, H. G. Roskos,

and J. Stake, Antenna-Integrated 0.6 THz FET Direct Detectors Based on CVD

Graphene, Nano Lett., 2014, 14 (10), pp 5834–5838.

3. A. Zak, M. A. Andersson, M. Bauer, J. Matukas, A. Lisauskas, H. G. Roskos,

and J. Stake, 20 μm gate width CVD graphene FETs for 0.6 THz detection, 39th

International Conference on Infrared, Millimeter and Terahertz Waves, IRMMW-THz

2014; The University of ArizonaTucson; United States, p. Art. no. 6956250, (2014).

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Integration strategy

Two integration concepts:• monolithic integration or System on Chip (SoC);

• heterogeneous integration or System in a package (SiP).

SiP

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Integration strategy

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Integration strategy

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Integration strategy

TFBAR

Cavity

Patch

radiator

Off-chip

capacitor

Off-chip

inductor

Ferroelectric

delay line

Adopted from pan European FP7 project HighMission

An example of a ferroelectric SiP integration

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Integration strategy

Heterogeneous integration (SiP) – multichip modulus on GaN-wafer carrier

GaN/wafer

carrier

chips on

Si/ferroelectric

substrates

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Requirements on GaN substrate

• ρ > 10 kΩ cm;

• surface should be passivated 22

Future plans

• Development of G-FET on LiNbO3 technology;

• bi-layer G-FET on Si with a band gap induced by a back gate;

• bi-layer G-FET on LiNbO3 with a band gap induced by spontaneous

polarization;

• Collaboration with Prof. Per Hyldgaard for modelling of

the bi-layer G-FET on LiNbO3 system;

• design and fabrication of G-FET based mixer and amplifier;

• Collaboration with other groups for the system integration.

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