NanoZEIT

Material Research for Electronic Devices

Prof. Dr.-Ing. Thomas Mikolajick

Chair of Nanoelectronic Materials, TU Dresden

1

Scientific Director NaMLab GmbH

Dresden, 20.10.2010

Outline

NaMLab Overview

Dielectric Materials

Microelectronic Devices and Characterization

2

Emerging Devices

Summary

NaMLabOverview

3

Overview

� NaMLab is based on a former Infineon/Qimonda

Corporate Research Department for Material Development

� NaMLab was established in 2006 as a joined venture between Qimonda and TU Dresden for

material development focused on semiconductor – especially memory - applications

HistoryFrom Idea to Trademark

4

� The clean room, characterization labs and offices were completed in 2008

� In April 2009 the University of Technology Dresden took over the shares from Qimonda and

the scope broadened towards Semiconductor, Sensor, Solar industrial applications

� Since June 2009 NaMLab receives a basic financing from the ministry of science and arts of

the free state of Saxony

Personal 2009/2010Status „Scientific Staff“

5

May June July Aug Sept Oct Nov Dec Jan Feb March April May June July Aug Sept

Administration 2 2 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3

Technicians 3 3 3 3 3 4 4 4 4 4 4 4 4 4 4 4 4

Senior Scientists 1 2 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4

Postdocs/Scientists 0 0 0 1 1 5 5 7 8 8 7 6 6 5 5 5 5

PhDs 6 6 6 6 7 9 9 9 13 13 13 13 13 13 13 13 13

Students (Hiwi/DA) 0 0 0 0 0 1 1 2 2 2 2 2 2 2 2 4 4

Total 12 13 16 17 18 26 26 29 34 34 33 32 32 31 31 33 33

2009 2010

Namlab develops

material solutions for tomorrows electronic devices

� Predominantly Dielectrics and Metal Electrode Materialsbut also Semiconductors with application/device focus

Mission

6

� New device concepts

� Electrical characterization including reliability

Namlab EquipmentAvailable equipmentDeposition:

- UHV Sputter cluster- Metal Evaporator - 2 MBE (Oxides / III-V semiconductors)-LPCVD furnace- Remote plasma furnace new Q2 2010

Processing:- Laser cutter- 4 wet benches- RTP furnace- Ebeam lithography new Q1 2010

Electrical characterization:

Competences

MBE MBE MBE MBE clusterclusterclustercluster

Plan:- UHV Sputter tool

(Q1 2011)- Plasma CVD

(Q4 2011)- III-V MOCVD

(Q4 2011)

- III-V etcher (Q4 2011)

7

Electrical characterization:- 3x fully equipped IV / CV setups with switch matrices upgraded Q4 2009- 2x Tester 200 mm- Tester 300 mm

- Flash Tester R.I.F.L.E- Thermotron station new Q4 2009

Physical characterization:- Photoluminescence setup new Q2 2010- AFM (CAFM, SSRM)- SEM - Ellipsometer- IR ellipsometer- Raman Microscope

SEM / SEM / SEM / SEM / EbeamEbeamEbeamEbeam----litholitholitholitho

PVD PVD PVD PVD Cluster Cluster Cluster Cluster

- Cryo Tester

(Q4 2010)

- Carrier lifetime measurement (Q2 2009)- Capacitance loss bridge (Q4 2011)

- XRD / XRR (Q1 2011)

NaMLab uses a broad cooperation network in order to close the experimental chain

� processing of test structures (capacitors etc.) and atomic layer deposition (ALD) together with the institute of Semiconductors and Microsystems (IHM) of the technical University of Dresden

Cooperation

8

of the technical University of Dresden

� physical analysis with IHM, IFW, FhG CNT …

� Integration into product relevant semiconductor processes with industrial partners

TU Dresden:- IHM (Semiconductor Technology), - IWW (Material Science and Nanotechnology)- IEE (Circuit Design and Network Theory) - IEE - IAP (Applied Photophysics)

Other Universities- IWW (TUBA Freiberg)- Nanometer Structure Consortia Lund- Italian University NanoElectronics Team - Anorganic Chemistry (RU Bochum)- Applied Physics (TU Eindhoven, Netherlands)- Department of Chemistry (U Helsinki, Finland)- IWE2 (RWTH Aachen)- TU Braunschweig- TU Ilmenau FEG

Cooperation withInstitutes:

- Center for Nanoelectronics (CNT), FhG, Dresden - Institut für Werkstoff Wissenschaften Leibniz- AMO GmbH. Aachen- Paul-Drude Insititut, Leibniz- Ges., Berlin- Institute for Semiconductor Physics (IHP- Research Center Dresden Rossendorf (FZD- Max-Planck Institute for Microstructure Physics- Commissariat à l´Energie Atomique (CEA- Institute for Integrated Systems and Device

9

- Institute for Integrated Systems and Device Technology (ISSB), FhG, Erlangen- Institute for Solid State Research (IFF) FZ Jülich- Institute for Microelectronics andMicrosystems (MDM), Agrate, Italy- IMEC, Leuven, Belgium- Institute for Leather and Plasticfoils (FILK) Freiberg- Institute for Ceramic Technologies and Systems( IKTS), FhG, Dresden

Researach Activities

Nano Devices

Nano Materials Characterization

DielectricesDielectricesDielectricesDielectricesHigh High High High kkkk ElectricalElectricalElectricalElectrical PhysicalNanowire Optical

CompetencesCompetencesCompetencesCompetences

10

Microelectronic Devices

Energy Harvesting

MemoryConcepts

Appl

icat

ions

Appl

icat

ions

Appl

icat

ions

Appl

icat

ions

Dielectric Materials

11

Materials

SrZrO3 for MIM capacitor

100

150

200

250

300

Inte

nsit

y [

cp

s]

500°C

650°C TiN

600°C SrZrO3

700°C

750°C

800°C

0

1

2

3

4

5

6

7

k = 33.6 +/- 1.4

k = 27.6 +/- 2.9

CE

T [

nm

]

High k dielectrics Competences

Motivation:Motivation:Motivation:Motivation:Applications in MIM capacitorsCET < 0.7 nm leakage current < 10-7 A/cm2

MetalSrZrO3

Metal

12

Results:

� SrZrO as dep: k-value up to 19 MBE similar to PVD SrZrO3

� Leakage current density of untreated PVD films is generally lower than MBD films

� Crystallisation of SrZrO3 into a cubic phase starts at 650°C

� PDA at 700°C results in a k-value of 28 for MBD and 34 for PVD

20 40 60

0

50

100

Inte

nsit

y [

cp

s]

2 Theta [°]

0 5 10 15 20 25 30 35 40 450

physical thickness [nm]

MEGAEPOS Team: A. Krause, M. Grube, E. Erben, W. Weber, U.Schröder

M. Grube et al., WODIM 2010

CaTiO3 for MIM capacitor

Motivation:Motivation:Motivation:Motivation:Applications in MIM capacitorsCET < 0.7 nm leakage current < 10-7 A/cm2

MetalCaTiO3

Metal

1,0 1,5 2,0 2,5 3,01E-8

1E-7

1E-6

1E-5

1E-4

1E-3

30 nm

20 nm15 nm

50 nm

40 nm

Le

ak

ag

e @

1V

(A

/cm

²)

CET (nm)

Pt / CTO / Ru with different thicknesses

• Thickness dependence of Tcryst

High k dielectrics Competences

13

Results:Results:Results:Results:• Small crystallites of CaTiO3 in

amorphous matrix• Epitaxial growth on specific Pt

grains

• Nanocrystallites with amorphous passivation(k ~ 53, low leakage)

• Full crystallized layer(k~ 100, higher leakage)

• Thickness dependence of Tcryst

KONDOR Team: A. Krause, M. Grube, E. Erben, W. Weber, U.Schröder

A. Krause et al., WODIM 2010

Conductive atomic force microscopy

50nm

CompetencesCompetences

Motivation:Motivation:Motivation:Motivation:Local correlation of physical and electrical results

14

ZrO2 vs. ZrAlO-stacks results:

- Al2O3 reduces leakage current and stabilizes the film during the PDA

- ZAZ shows a CET ~0.9nm and J~10-8 A/cm2

- High leakage density, trapping and breakdown at boundaries

MEGAEPOS

D. Martin, APL 95 142906

D. Martin, WODIM 2010, Submitted to Journal of Vac. Sci. and Technol. B.

Team: D. Martin, W. Weber, U. Schroeder

Ferroelektrische FeFETs

-3 -2 -1 0 1 2 3

-2,0x10-9

-1 ,5x10-9

-1 ,0x10-9

-5 ,0x10-10

0,0

5,0x10-10

1,0x10-9

1,5x10-9

2,0x10-9

Ele

ctr

ic D

isp

lac

em

en

t

Voltage [V]

hi.-kAFE

Higher Si cont.

Microelectronic devices

initial pulseinitial pulseinitial pulseinitial pulse

VVVVtttt VVVVtttt

variable pulsevariable pulsevariable pulsevariable pulse

Applications

Motivation:Motivation:Motivation:Motivation:Development of a ferroelectric material stable on Si

~1V

15

� Ferroelectricity (incl. Piezo) can be provoked in 10 (-30) nm hi-k films

� Beneficial FE combination: low k vs. high Pr (compared to typical FE materials)

� FE retention (> 10years) & fast switching speed (< 20 ns)

-2 -1 0 1 2

-2,0x10-9

-1,0x10-9

0,0

1,0x10-9

2,0x10-9

3,0x10-9

4,0x10-9

Ele

ctr

ic D

isp

lac

em

en

t

Vo ltage [V ]

Voltage [V]Higher Si cont.

Hi-kFE

Lower Si cont.

(program/erase)(program/erase)(program/erase)(program/erase) variable pulsevariable pulsevariable pulsevariable pulse(program/erase)(program/erase)(program/erase)(program/erase)

MERLIN Team: S. Knebel, A. Graham, U. Schröder, J. Müller (CNT)

Low temperature Al2O3 ALD

Motivation:Motivation:Motivation:Motivation:- diffusion barriers (OLED, organic PV)- passivation layer (PV) � broad field- layer for enhanced electrical and mechanical reliability (MEMS) of applications- low T (<= 200°C) necessary due to sensitive surfaces

ALD dielectrics Competences

16

ResultsResultsResultsResults::::- Low T Al2O3 ALD (100°C – 200°C) with comparable results to 300°C POR for O3- Development of low T process on MEMS products

KONDOR Team: E. Erben, S. Jakschik, U.Schröder

E. Erben et al., BALD 2010

SiN

AlCu

Device and Characterization

17

Characterization

Leakage Currents and Defect Characterization

of High-k MOSFETs

Motivation:Motivation:Motivation:Motivation:Leakage currents increase off-power consumption and degrade device performance and reliability• Gate edge characterization and process adjustment• Reliability for GlobalFoundries

Important Results:Important Results:Important Results:Important Results:Ncp

Microelectronic devices Applications

18

Important Results:Important Results:Important Results:Important Results:

• Nitride spacer necessary to avoid birds beaks at the

costs of increased GIDL

�GIDL can be reduced to SiO2 spacer level by

improving high-k removal process

• Permanent PFET SILC increase is still controlled by

interface layer

Ncp

SILC

MEGAEPOS Team: G.Roll, S.Knebel, S. Jakschik

Roll et al., ESSDERC2010; Roll et al., WODIM 2010

SiMotivation:Motivation:Motivation:Motivation:

Charge trap is seen as next generation cell concept for NAND

flash beyond floating-gate. Stack can be adjusted towards high

reliability for automotive applications.

-0.1

0.0

0.1

SONOS

Si

ONO

7

Charge trapping memory Applications

100

CC-Methode

Ct-Methode

19

3 4 5 6 7 8 9 10-1.0

-0.9

-0.8

-0.7

-0.6

-0.5

-0.4

-0.3

-0.2

-0.1

meas data

modelling

∆∆ ∆∆V

T [

V]

VT_prog

[V]

0.5h

1h

2h

4h

8h

16h

MLC Retention lossmodeling

Bias dependent loss rateConst. Cap method � layer charact.

CT method � product relevant

10n 100n 1µ 10µ 100µ 1m 10m 100m 1 10 1000

1

2

3

4

5

6

+/- 6V

+/- 8V

+/- 10V

+/- 12V

+/- 14V

+/- 16V

+/- 18V

VF

B [

V]

Pulsetime [s]

Multi-layer charge trap stackcharacterisation

Gossamer Team: Th.Melde, E. Yurchuk, J.Schönlebe

T. Melde et al., IIRW 2010E. Yurchuk, AMR 2009

100

101

102

103

104

105

-400

-300

-200

-100

0 Ct-Methode

∆ U

fb /

mV

t / s

25 C

85 C

145 C

200 C

Important Results:Important Results:Important Results:Important Results:• development of empirical model for prediction of MLC retention loss

• investigations in bias dependent retention loss revealing possibilities to

extract charge dipole in trapping layer

Charge trapping memory Applications

20

Current Project: EU-FP7 “Gossamer” (25nm NAND flash)

Initiated projects: Cool Silicon „E3NVM“ (high density nvSRAM)

Gossamer Team: Th.Melde, E. Yurchuk, J.Schönlebe

Memristor

MotivationMotivationMotivationMotivation::::• “4th device” - Development of test-structures • Electrical characterization of the different memory concepts• Assessment and comparison

Applications

21

Results:Results:Results:Results:

- sub-µ electrode structures developed

- 1st measurements on samples from project

partners ongoing

MUFUTeam: S.Slesazeck, H.Mähne

bottom electrodes as starting pointfor the integration of semiconductingSTT and organic memory

Partner: Partner: Partner: Partner: • IAPP TU-Dresden:organic memory• FZD: spin transfer torque memory(STT) (based on metallic andsemiconducting materials)

Resistive RAM/ Memristor based on TiOx

1E-13

1E-11

1E-9

1E-7

1E-5

1E-3

Cu

rre

nt

(A)

1

23

4SET

RESET

1E-15

1E-13

1E-11

1E-9

1E-7

1

2

3

4

Current (A)

Memristor Applications

Pt (20nm)

TiO2(30nm) 7sccm

Al (400nm)

22

Results:- Produced RRAM devices based on TiO2

- Integrated switchable diode - Multilevel states- Cycle endurance > 100

-3 -2 -1 0 1 21E-15

Voltage (V)

-0.50 -0.25 0.00 0.25 0.501E-17

5

Voltage (V)

HanselTeam: S.Slesazeck, H.Mähne

PV-cell front side, here w/o texture

PV-cell back side

ALD/CVDALD/CVDALD/CVDALD/CVD PVDPVDPVDPVD

τALD/CVD

> τ PVD

Passivation layers for crystalline solar cellsEvaluation of Chemical and physical vapor deposition

Energy Harvesting Applications

23

Effect: Effect: Effect: Effect: Negative fixed charge in Al2O3 repels generated carriers from the deteriorated surface

Results: Results: Results: Results: Compared deposition methods: ALD, PECVD, PVD

� All chemical methods ensure a high carrier life time

� For PVD the interface is damaged significantly, lifetime can not be enhanced by negative

fixed charge

side, here w/o texture

Team: F.Benner, M.Tarasova, P. Moll, E.Erben, S. Jakschik

MERLIN

Sperlich et al., PV-SEC2010; Erben et al., BALD2010

a)a)a)a)

Si nano wires for Li-ion battery anodes

Motivation:

-10x more Li storage then w/ C intercalation

- Semiconductor compatible process

Application:

- More then More SOC battery

- high capacity anodes

Energy Harvesting Applications

24

-0.5 0.0 0.5 1.0 1.5 2.0 2.5-0.16

-0.14

-0.12

-0.10

-0.08

-0.06

-0.04

-0.02

0.00

0.02

0.04

sp

ec

ific

cu

rre

nt

[mA

]

Potential Li/Li+ [V]

485052545658606264

-100

-50

0

50

100

150

200

250

300

Binding Energy (eV)

c/s

XPS Lithium peak in lithiated Silicon nano wires

Si-nanowires lithiated

Results:Demonstrated Li alloying of- Si nanowires- NiSi core and Si shell nanowires

Chan, Nature 2008

Team: W.Weber, S.Jakschik

Jakschik et al., ISE2010

Testchip C11 Technology

PD arrays for Miniarray for

Photo Diodes

Motivation:Motivation:Motivation:Motivation:Cost reduction for manufacturing color sensitive photodiodes by novel filter layers

Improvement of color sensitivity by new conceptual approach

Applications

25

Results:

� Setting-up complete value chain for optical sensor development at NaMLab:

� Test vehicle designed with photodiode arrays for manual and automatic measurement (in

cooperation with electrical engineering TU Dresden)

� Pipecleaner Lot running at Infineon Dresden, 1st samples expected E10/2010

PD arrays formanual measurement

Miniarray forautomatic read-out

MERLIN Team: S. Slesazeck, A. Wachowiak

Photocurrent Spectral Response

Color Sensitive Photodiode:

Simulation results

3.0E-11

3.5E-11

4.0E-11

4.5E-11

ph

oto

cu

rre

nt

[A /

µm

]

1.5

2.0

2.5

spe

ctra

l se

nsi

tiv

ity

X

Y

Z

2-dim. TCAD process and device simulationusing Synopsys tools

•solid human eye•dashed photodiode

Photo Diodes

Photodiode

Applications

26

0.0E+00

5.0E-12

1.0E-11

1.5E-11

2.0E-11

2.5E-11

3.0E-11

300 400 500 600 700 800 900

ph

oto

cu

rre

nt

[A /

µm

]

wave length [nm]

human eye vs. linear combination ofsensor response

-0.5

0.0

0.5

1.0

1.5

300 500 700

spe

ctra

l se

nsi

tiv

ity

wave length [nm]

Z

ARB

X'

Y'

Z'

ARB'

tunable sensor response(spectral illumination 1mW / cm²)

Outlook: Hardware Verification

MERLIN Team: S. Slesazeck, A. Wachowiak

IR-Investigation of masks structures

0.1

0.3

0.5

0.7

0.9

500 1500 2500 3500

inte

nsi

ty [

a.u

.]

wavenumber [cm-1]

tanψisospace

dense

isoline

CD 360

CD 300CC

CD 260C 0.9

0.1

0.3

0.5

0.7

0.9

500 1500 2500 3500

Inte

nsit

y [a

.u.]

wavenumber [cm-1]

tan ψ CD 100

CD 130

CD 260

CD 300

Competences

Motivation:Motivation:Motivation:Motivation:Investigation of IR Spectroscopymeasurement capabilitieson mask structures

27

Results:Results:Results:Results:Structures with different CDs do not deliver different spectraReason: steady ‘CD to pitch ratio’� Void is not changing hence no change in EM-Approximation

Comparison for spectra taken within ‘iso line’, ‘dense’ and ‘iso space’ areas are varying.�Structures with same CD but different ‘CD to pitch ratio’ have partially different spectral responses

-0.6

-0.3

0

0.3

0.6

0.9

500 1500 2500 3500

inte

nsi

ty [

a.u

.]

wavenumber [cm-1]

cos ∆isospace

dense

isoline

500 1500 2500 3500wavenumber [cm-1]CD 130

CD 180

CD 100

≙ Measurement Point-0.6

-0.1

0.4

0.9

500 1500 2500 3500

Inte

nsit

y [a

.u.]

wavenumber [cm-1]

cos ∆CD 100

CD 130

CD 260

CD 300

Cool Silicon Team: M. Krupinski, T. Hingst, J. Heitmann

Emerging Devices

28

Devices

Conductive carbon electrodes for

microelectronics

Motivation:Motivation:Motivation:Motivation:To have a stable electrode material with good electrical characteristics and deposition properties to replace poly silicon at the smallest ground-rules.

ResultsResultsResultsResults::::

Si

CPt/Ti

SiO2

Carbon based devices Applications

29

ResultsResultsResultsResults::::

• Deposition of conductive carbon on

SiO2 and Al2O3 dielectrics

• MIS capacitors show excellent CV

and leakage characteristics

SEM images of a 60 nm

carbon film on a 4.2 nm

thick silicon oxide

dielectric

CV characteristic of carbon

electrodes on a 4 nm thick

silicon oxide dielectric

A. Graham, Journal of Applied Physics, accepted

KONDOR Team: A. Graham

0 . 0

Vi n

Vo u t

-1 .5 -1 .0 -0 .5 0 .0

-1 .5

-1 .0

-0 .5

0 .0

V o

ut

V in

First nanowire inverter without dopants

Applications

Motivation:Motivation:Motivation:Motivation:Fine –grain reprogrammable technologies have been missing so-far. Doping difficulties for nanometer-scale semiconductors

30

0 5 0 0 1 0 0 0 1 5 0 0

- 2 . 0

- 1 . 5

- 1 . 0

- 0 . 5

0 . 0

Po

ten

tia

l [V

]

T i m e [ s ]

ResultsResultsResultsResults::::Design and fabrication of the first dopant free inverterNext StepsNext StepsNext StepsNext Steps:Single nanowire inverter with implemented core/shell technologyRe-programmable NAND / NOR gatter

Team: A. Heinzig, W. Weber

A. Heinzig et al.

MRS Spring meeting

T. Mikolajick et al. Invited paper

NanoFair Proc. 2010

NODE

Nanowire based sensors

Motivation:Motivation:Motivation:Motivation:Utilize high sensitivity of nanoscale nanowire junctions for sensing applications

Joint project with the chair of materials science and nanotechnology (Prof. G. Cuniberti)Combine expertise in functionalization (Max Bergmann center) with nanowire technogy at Namlab.

Applications

biomolecules

31Team: S. Pregl, W. Weber

ResultsResultsResultsResults::::• Nanowire alignment through contact printing• High electrical sensitivity to humidity as surface to volume ratio increases• First humidity sensor with APTES functionalization

InnovaSens

Nanowire ambient sensitivity Nanowire sensorAligned nanowires

for sensor array

receptor

nanowire

4 µm

Summary

32

� NaMLab is a research organization of TU Dresden

� NaMLab focuses on Materials for Electronics

� A number of activities on materials/devices and

Summary

33

� A number of activities on materials/devices and

characterization have been started in 2009/1010

�…There is more to come !!!

34