1

Advanced Slurry/Pad Technologies for Cu/Low-K CMP Process

JSR Confidential 2

Contents

CMP requirements for 65nm and beyondConcepts of JSR Soft polishingApproach from slurry improvement

Soft-brasiveTM TechnologiesOptimization of ingredient chemicals

Approach from pad improvementFiller Pad Technology

Results of slurry/pad combinationConclusions

JSR Confidential 3

General Requirementto CMP process for 65nm-generation and beyond.

Soft polishing to prevent damage of delicate film stack and structure with low-k dielectric materialsHigher planarity…Low dishing / erosionFaster bulk polishing for higher through-putLow defects

JSR Confidential 4

Causes of Scratch

Contamination of large particlesUncontrolled shape and morphology of abrasivesUncontrolled surface status of padScum (cleanliness)Coagulation and precipitation of ingredients and polished materials by

sudden pH change during the processUnnecessarily high down-force

JSR Confidential 5

Requirement for Cu/Low-K CMP Process

Cu wiring

Low-K dielectrics

Pad

Slurry

Dishing Erosion

Scratch Peeling

Minimal Low-K Damage and Less Scratches High Planarity ・ Fast Removal Rate

Approach by Slurry/Pad Technology

JSR Confidential 6

Soft-brasive Technologies

Polymer Abrasives Colloidal Silica Abrasives

Composite Abrasives

Totally controlled shape and morphologyMinimized large particle formation by

well-established production processCushion effect to local high down-force

JSR Confidential 7

945

72 29 10 0123 31 5 3 00

200400600800

1000120014001600

Fumed silica Colloidalsilica

Compositeabrasive A

Compositeabrasive B

Polymerabrasive

Cou

nt /

waf

er ScratchPeeling

Scratch Counts by Various AbrasivesLKD : JSR LKD(k=2.2) CMP machine : EPO112 Defect measurement : KLA2112

65235760625945TaN-RR (A/min)

Polymer abrasive

Composite abrasive B

Composite abrasive A

Colloidal silica

Fumed silica

Soft-brasiveTM Technologies accomplish less scratches and Low-K damages.

JSR Confidential 8

High Performance Cu Slurries

ChemicalsFor scratch prevention

Stabilization of polished material to prevent coagulation and precipitation

For high planarity / fast removal rateControlling the etching rate to prevent dishing and erosion.Controlling the strength of passivation layer on the Cu surface.

JSR CMS7400/8400 series

JSR Confidential 9

Dishing/Erosion Performance with Over Polish Margin (Cu Polish)

0

200

400

600

800

1000

0 20 40 60 80 100 120

Over Polish (%)

Dis

hing

/Ero

sion

(A)

100umDishing120umPadDishing4.5/0.5umErosion0.35/0.35umErosion

CMS7400 series exhibit excellent Dishing/Erosion performance with wide over polish margin.

JSR Confidential 10

Down Force Dependency

0

400

800

1200

0 5

Down force (psi)

Cu

rem

oval

rate

(nm

/min

)

CMS7400

Conventionalslurry

CMS7400 series shows smaller down force dependency.

Low Down Force Polishing!!

JSR Confidential 11

Innovative Technology of JSR CMP Pads

When exposed to polishing liquids, the water soluble particles (WSP) at the pad surface dissolve, forming micro pores.

WSP in the pad bulk remains solid so the pad maintains a very low compressibility providing superior planarizationefficiency and consistent pad-to-pad quality

The size, shape and distribution of the pores are well-controlled, being directly related to WSP particle size, shape and dispersion.

JSR’s Innovative Solid Pad

Micro PoresMatrix Polymer

Dressing

Water Soluble Particles (WSP)

JSR Confidential 12

Low Defect & Good Planarity Concept

Bad Planarity

Good Defect Performance

Hard

Soft

Good Planarity

Less Defect

=

=

JSR CMP PadSolid pad with WSP

Good Planarity

Bad Defect Performance

Soft PadHard Pad

JSR Pad: Excellent defect performance without sacrificing RR/Planarity performance.

JSR Confidential 13

Hardness vs. Scratch

0

10

20

30

40

50

60

65 67 69 71 73

Hardness

Scra

tch

Cou

nts

(KLA

Ste

alth

) P-TEOS Blanket Wafer Polish

Reduction of the hardness affects the scratch counts

Soft Polishing!!

JSR Confidential 14

Hardness vs Removal Rate

500

600

700

800

900

60 65 70 75

Hardness

Cu R

emov

al R

ate

(nm

/min

.) Down Force = 2.9 psi

2.2 psi

1.5 psi

Cu Blanket Wafer Polish

Surface micro pore structure maintains the constant removal rate over the variation of hardness.

JSR Confidential 15

WSP amount vs. Hardness/Planarity

0

20

40

60

80

100

1 2 3

WSP amount (normalized)

Har

dnes

s

400

500

600

700

800

LSH

(A)

The polymer matrix reinforced by WSP gives wide margin of planarity over the deviation of bulk hardness.

SKW-7 Pattern Wafer Polish

JSR Confidential 16

Polishing conditionsPolisher: Mirra MesaSlurry: JSR Barrier Slurry

Defect evaluationSP1 tbiLow throughputHigh Sensitivity recipe(calibrated on silicon):

CMP Pad Defect ComparisonBarrier Slurry Evaluation

Copper Blanket Wafer Defect (SP1 DCO)

0

5000

10000

15000

20000

25000

Conventionalhard pad

Conventional Soft Pad

JSR Std JSR Soft

Pad Type

SP

1 D

CO

Def

ect C

ount

s

The defect level of JSR pads is more than 10x less than conventional hard pad.Defect level of JSR soft pads are close in performance to conventional soft pad.

JSR Confidential 17

Dishing/Erosion Comparison

• JSR pads show better topography correction compared with conventional soft pad.

• JSR standard and soft pads show comparable performance.

4.5/0.35 Erosion (Mask831)

0

50

100

150

200

250

300

0 10 20 30 40 50 60 70 80 90 100

Polish Time [ sec ]

Eros

ion

[ A ]

St'd (1.5/0.5/1.4)St'd (3.0/0.5/1.4)JSR Soft PadJSR Very Soft PadConventional Soft

100/100 Dishing (Mask831)

0

50100

150

200

250

300

350

400

0 10 20 30 40 50 60 70 80 90 100Polish time [ sec ]

Dis

hing

[ A

]

St'd Pad (1.5/0.5/1.4）St'd (3.0/0.5/1.4）JSR Soft PadJSR Very Soft PadConventional Soft

JSR Confidential 18

CMP Process for Cu/Low-K

Scratch and Low-K Damage

Filler Pad Technology

High Planarity

JSR CMS7400/8400 series

Advanced Cu/Low-K CMP Process

JSR Confidential 19

Cu CMP using CMS7400/Filler Pad

160Dishing [A] (120um pad)

116

279

404

20

127

1.8

10,020

Cu Polish

Erosion [A] (L/S=0.35/0.35)

Erosion [A] (L/S=4.5/0.5)

Dishing [A] (L/S=100/100)

Over Polish (%)

End Point Time (sec)

WIWNU (%)

Cu RR (A/min)

High Cu removal rate and good uniformity

JSR Confidential 20

Barrier Metal CMP using CMS8400/Filler Pad

1,360TaN RR (A/min)

884Ta RR (A/min)

2222Dishing [A] (120um pad)

66Scratch Counts (OM)

5656Erosion [A] (L/S=0.35/0.35)

170170Erosion [A] (L/S=4.5/0.5)

9898

60

404

Barrier Metal Polish

Dishing [A] (L/S=100/100)

Polish Time (sec)

Cu RR (A/min)

Excellent planarity and less scratches

JSR Confidential 21

ConclusionsHigh PerformanceHigh Performance SlurriesSlurries exhibit excellent Dishing/Erosion performance and high Cu removal rate.Pad surface control is the key technology for less scratches. JSR proprietary Filler Pad TechnologyFiller Pad Technology enables the soft and controlled micro-pore structured surface for less scratches while maintaining sufficient removal rate and planarity.Advanced Cu/Low-K CMP process is proposed using the combination of High PerformanceHigh Performance SlurriesSlurries with Filler Pad TechnologyFiller Pad Technology.