Development of HIPIMS Technology for

Superconducting Coated Cavities

G. Terenziani, S.Calatroni, A. P. Ehiasarian, T. Junginger, S. Aull

Outline

• From Dc Magnetron Sputtering to HiPIMS

• HIPIMS Samples Analysis:

OES

MS

SEM

XRD

RRR

• HIPIMS Cavity Results

From DCMS To HiPIMS

© Andre Anders, 201011

Generalized Structure Zone Diagram

A. Anders, Thin Solid Films 518, 4087 (2010).

derived from Thornton’s diagram, 1974

Based on “Structure Zone Model” - Thornton, J.Vac. Sci. Technol. 11 (1974) 666

Outline

• From Dc Magnetron Sputtering to HiPIMS

• HIPIMS Samples Analysis:

OES

MS

SEM

XRD

RRR

• HIPIMS Cavity Results

Vacuum, Surfaces & Coatings Group

Technology Department

HIPIMS Samples – Optical Emission

Spectroscopy (OES)

50 88 125 165 180 270 340 410 480 550

21

37

53

69

85

Pulse Duration (µs)

Peak

Curr

ent

(A)

0.05000

0.1250

0.2000

0.2750

0.3500

0.4250

0.5000

0.5750

0.6500

Nb II / Nb I Ratio

G. Terenziani, S. Calatroni, A.P. Ehisarian, T.

Junginger12

Vacuum, Surfaces & Coatings Group

Technology Department

HIPIMS Samples – Optical Emission

Spectroscopy (OES)

0

0.02

0.04

0.06

0.08

0.1

0.12

0.14

0.16

0.18

0 0.2 0.4 0.6 0.8 1 1.2

Ra

tio

Nb

+/N

b

Current Density (A*cm-2)

Ratios (Nb+/Nb) vs Peak Current Density @ different pulse width

Ratio I @ 50 us

Ratio I @ 200 us

Ratio I @ 550 us

G. Terenziani, S. Calatroni, A.P. Ehisarian, T.

Junginger13

Outline

• From Dc Magnetron Sputtering to HiPIMS

• HIPIMS Samples Analysis:

OES

MS

SEM

XRD

RRR

• HIPIMS Cavity Results

Vacuum, Surfaces & Coatings Group

Technology Department

0 20

1

10

100

1000

10000

100000

1000000

Inte

nsity

Energy

Equation y = a + b*x

Weight No Weighting

Residual Sum of Squares

0.03801

Pearson's r -0.99042

Adj. R-Squar 0.98028

Value Standard Erro

IntensityIntercept 5.44624 0.02626

Slope -0.2808 0.00727

0 20

1

10

100

1000

10000

100000

1000000

Inte

nsity

Energy

Equation y = a + b*x

Weight No Weighting

Residual Sum of Squares

0.37334

Pearson's r -0.99248

Adj. R-Square 0.98487

Value Standard Erro

IntensityIntercept 4.86924 0.02183

Slope -0.16911 0.0021

0 20

1

10

100

1000

10000

100000

1000000

Inte

nsity

Energy

Equation y = a + b*x

Weight No Weighting

Residual Sum of Squares

0.03287

Pearson's r -0.99008

Adj. R-Square 0.97922

Value Standard Error

IntensityIntercept 5.87232 0.01752

Slope -0.46038 0.01499

Zone I Zone II

Zone III

HIPIMS Samples – Mass Spectrometer

(MS) – Nb+

case – 0.5 Acm-2

59.5% 29%

11%

G. Terenziani, S. Calatroni, A.P. Ehisarian, T.

Junginger15

Vacuum, Surfaces & Coatings Group

Technology Department

0 20

1

10

100

1000

10000

100000

1000000

Inte

nsity

EnergyeV

Equation y = a + b*x

Weight No Weighting

Residual Sum of Squares

0.01586

Pearson's r -0.98183

Adj. R-Squar 0.96

Value Standard Erro

IntensityIntercept 5.97114 0.02368

Slope -0.6212 0.04002

0 20

1

10

100

1000

10000

100000

1000000

Inte

nsity

EnergyeV

Equation y = a + b*x

Weight No Weighting

Residual Sum of Squares

0.01039

Pearson's r -0.99757

Adj. R-Square 0.99498

Value Standard Error

IntensityIntercept 5.68381 0.01009

Slope -0.29305 0.0038

0 20

1

10

100

1000

10000

100000

1000000

Inte

nsity

EnergyeV

Equation y = a + b*x

Weight No Weighting

Residual Sum of Squares

0.17679

Pearson's r -0.99539

Adj. R-Squar 0.99071

Value Standard Erro

IntensityIntercept 5.08897 0.01364

Slope -0.1489 0.00144

Zone I Zone II

Zone III

HIPIMS Samples – Mass Spectrometer

(MS) – Nb+

case – 1.3 Acm-2

49.5% 33.3%

12%

G. Terenziani, S. Calatroni, A.P. Ehisarian, T.

Junginger16

Vacuum, Surfaces & Coatings Group

Technology Department

0 5 10 15 20 25 30

1

10

100

1000

10000

100000

1000000

Inte

nsity

Energy

Equation y = a + b*x

Weight No Weighting

Residual Sum of Squares

0.01735

Pearson's r -0.98468

Adj. R-Square 0.96621

Value Standard Error

IntensityIntercept 6.01073 0.02477

Slope -0.70913 0.04186

0 10 20 30

1

10

100

1000

10000

100000

1000000

Inte

nsity

Energy

Equation y = a + b*x

Weight No Weighting

Residual Sum of Squares

0.26334

Pearson's r -0.99737

Adj. R-Square 0.99471

Value Standard Error

IntensityIntercept 5.37594 0.00808

Slope -0.14611 9.00585E-4

0 20

1

10

100

1000

10000

100000

1000000

Inte

nsity

Energy

Equation y = a + b*x

Weight No Weighting

Residual Sum of Squares

1.65281

Pearson's r -0.97238

Adj. R-Square 0.94526

Value Standard Error

IntensityIntercept 4.16017 0.02843

Slope -0.06511 0.00111

Zone I Zone II

Zone III

HIPIMS Samples – Mass Spectrometer

(MS) – Nb+

case – 2 Acm-2

48.4%

50.6%

1%

G. Terenziani, S. Calatroni, A.P. Ehisarian, T.

Junginger17

Outline

• From Dc Magnetron Sputtering to HiPIMS

• HIPIMS Samples Analysis:

OES

MS

SEM

XRD

RRR

• HIPIMS Cavity Results

Vacuum, Surfaces & Coatings Group

Technology Department

DCMS Cross Section Structure

G. Terenziani, S. Calatroni, A.P. Ehisarian, T.

Junginger22

1 um

Cu

Nb

C

Surface features in HIPIMS seem larger

than in DCMS but the column size in

cross section appears smaller in

HIPIMS. The large surface features in

HIPIMS could be comprised of several

columns whose inter-columnar

boundaries are so dense that they

appear as single crystals.

Vacuum, Surfaces & Coatings Group

Technology DepartmentG. Terenziani, S. Calatroni, A.P. Ehisarian, T.

Junginger23

Cross Section Structure -

Comparison

In neither DCMS nor HIPIMS there doesn't seem to be a large-scale epitaxial growth of

the films. Rather, the growth in both cases starts out with numerous nucleation sites

probably with different grain orientation and the subsequent growth is a competition

between different grain orientations.

In HIPIMS it seems that near the coating-substrate interface there is a thicker region

where there is competitive growth.

This is followed by a process of grain selection where winning grains widen to take up

the entire area.

It could be speculated that during the selection process, DCMS grains do not densify

their grain boundaries whilst HIPIMS grains can do that due to the extra surface mobility

of metal ions.

Because of this the morphology of the HIPIMS surface appears to contain larger

features than DCMS.

Outline

• From Dc Magnetron Sputtering to HiPIMS

• HIPIMS Samples Analysis:

OES

MS

SEM

XRD

RRR

• HIPIMS Cavity Results

Vacuum, Surfaces & Coatings Group

Technology Department

HIPIMS Samples – X-Ray Diffraction

Cu <200>

Cu <200>

Cu <200>

Nb <110>

Nb <110>

Nb <110>

G. Terenziani, S. Calatroni, A.P. Ehisarian, T.

Junginger25

Vacuum, Surfaces & Coatings Group

Technology Department

HIPIMS Samples – X-Ray Diffraction

G. Terenziani, S. Calatroni, A.P. Ehisarian, T.

Junginger26

0

1

2

3

4

5

6

0

5

10

15

20

25

0 0.5 1 1.5 2 2.5

Thic

kne

ss (

um

)

Rat

io N

b<1

10

> /

Cu

<2

00

>

Current Density (A/cm2)

Ratio

Sample Thickness

Outline

• From Dc Magnetron Sputtering to HiPIMS

• HIPIMS Samples Analysis:

OES

MS

SEM

XRD

RRR

• HIPIMS Cavity Results

Vacuum, Surfaces & Coatings Group

Technology Department

HIPIMS Samples – Residual

Resistance Ratio (RRR)

G. Terenziani, S. Calatroni, A.P. Ehisarian, T.

Junginger28

0

5

10

15

20

25

0

5

10

15

20

25

0 0.5 1 1.5 2 2.5 3

Nb

<11

0> / C

u <2

00

>

RR

R

Current Density (A/cm2)

Comparison RRR Vs Crcistallographic Orientation

RRR Vs Current Density @200 us

Nb <110> / Cu <200>

Outline

• From Dc Magnetron Sputtering to HiPIMS

• HIPIMS Samples Analysis:

OES

MS

SEM

XRD

RRR

• HIPIMS Cavity Results

Vacuum, Surfaces & Coatings Group

Technology Department

HIPIMS on 1.3 GHz Cavity – Deposition System

1.3 GHz Cavity

Magnet

Central Cathode

413 mm

G. Terenziani, S. Calatroni, A.P. Ehisarian, T.

Junginger30

Vacuum, Surfaces & Coatings Group

Technology Department

HIPIMS on 1.3 GHz Cavity M2.3 – Rs

Vs T

Δ/kb = 18 K

RRR = 13.1

RRES = 4.5 nΩ

G. Terenziani, S. Calatroni, A.P. Ehisarian, T.

Junginger31

J = 2 A/cm2, τ = 200 us

Surface treatment: EP + SUBU

Vacuum, Surfaces & Coatings Group

Technology Department

HIPIMS on 1.3 GHz Cavity M2.7 – Rs

Vs T

Δ/kb = 18 K

RRR = 15

RRES = 6.5 nΩ

G. Terenziani, S. Calatroni, A.P. Ehisarian, T.

Junginger32

J = 2 A/cm2, τ = 200 us

Surface treatment: EP

Vacuum, Surfaces & Coatings Group

Technology DepartmentG. Terenziani, S. Calatroni, A.P. Ehisarian, T.

Junginger33

There is an increase of

about 15 nΩ from low field

to 15 MV/m between the

curves measured just

below and just above λ

transition

Q-slope is influenced by

thermal boundary, but it is

not the dominant effect

(≈7%)

HIPIMS on 1.3 GHz Cavity M2.7 – Rs

Vs

Eacc

Vacuum, Surfaces & Coatings Group

Technology Department

HIPIMS on 1.3 GHz Cavity - Results

G. Terenziani, S. Calatroni, A.P. Ehisarian, T.

Junginger34

Thank you for your attention