[PPT] - Tool Cleanliness Tool Cleanliness Characterization for Improving PowerPoint Presentation

SLIDE 1

Tool Cleanliness Tool Cleanliness Characterization for Improving Characterization for Improving Productivity and Yields Productivity and Yields

Victor K.F. Chia, Ph.D.

victor.chia@balazs.com

Victor K.F. Chia, Ph.D.

victor.chia@balazs.com

SLIDE 2

Reducing Contamination

Agenda

Introduction Tool components

Starting material selection and bulk characterization Surface cleanliness

Chemical characterization
Physical characterization

Completed tools

Tool cleanliness specification

Particles
Metals
Organics

Tool escalation case study Conclusion

New and used components PECVD chamber

SLIDE 3

Reducing Contamination

Introduction

Tool parts cleanliness is an invisible parameter that must be controlled to

enable clean processing

The target contaminants affecting process yields are particles, metals and

rganics

In the sub-100 nm technology node even irreducible differences in the

components of identical tool chambers can influence yield and mean time between failure (MTBF)

The first line of defense for a fab is to have clean tools for processing, from

acceptance trials of the new tool to after each PM. Only with clean tools can a fab maximize its yield by increasing overall equipment productivity and wafer throughput for increased profit margin

This may be accomplished with strict quality control of the supplier chain for

starting materials, machine shops, cleaning vendors and contract

manufacturing. In addition, cleanliness specifications must be in place for

the BOM.

This presentation reviews cleanliness specifications for components and

completed tools and characterization methods for verifying their cleanliness

SLIDE 4

Reducing Contamination

Starting Materials

Requirements

The materials used in the BOM, including

lubricants and grease, must be compatible to its function and cleanliness requirements

Multi-alloy parts must be cleanable Bulk material characterization is important as the

root source of wafer contamination may be from the bulk of the material; no amount of cleaning will remove this contamination source

Metals Al Ni SST Mo Ti Ta Cu / Cu Alloys Coatings Ni Plating Au Plating Powder Coating Paint Alodine Anodized Zn Plastics PEEK PTFE Polyimide Polyethylene Kapton Viton Calrez Ceramics Alumina Glass Saphire DLC Quartz Assemblies Welded Aluminum Welded Steel Alloys Brazed Bonded Flex Circuit

Com plex Wafer Arm Assem bly

Common materials used in build of materials (BOM)

SLIDE 5

Reducing Contamination

Starting Materials Characterization

O-rings with inorganic fillers like SiO2, BaSO4, ZnO,

C or TiO2 lasts about 6,000 wafer counts before particulation issues occurs

O-rings using organic filled material can reach

upwards of 20,000 wafer counts with reduced number of metallic particles escalations

Layer 1 Layer 4 Substrate Layer 2 Layer 3

80E 80E 80E 80E

Mass Spectrum

100000 200000 300000 400000 500000 20 40 60 80 100 120 140 160 180 200 m/z (amu) Signal Intensity (c/s) O-Ring Defect S Fe Mn I C Ni Mo

Metals on wafer using VPD ICP-MC Mass Spectrum

20000 40000 60000 80000 100000 10 20 30 40 50 60 70 80 m/z (amu) Signal Intensity (c/s)

Defect I nclusion that is only visible under UV light

Si O X Y

Quartz Si O X Y

100 1000 10000 100000

1

1 2 3 4

Sampling Depth in µm ICP-MS Signal Intensity (c/s) Iron (Fe) Copper (Cu) Zinc (Zn)

w afer

Fe Cu Zn

Fe “clean” “dirty”

Ceram ic

Metal or metal alloy whose melting temperature is considerably lower than the sintering temperature of the ceramic body are used to fill voids in the ceramic to achieve a particular physical property – conduction, brazing, etc.

Laser ablation I CP- MS

w afer

O-Ring

O-ring defect

Fe Mo S I

SLIDE 6

Reducing Contamination

Metal Escalation

Escalation: Metal contamination
Verify root cause: fix short and

replace ceramic rods

Escalation resolved

Element DL 1 2 3 4 5 6 7 8 9 10 11 12 Al 50 130 590 58000 5260 420 590 1500 12500 15000 2300 350 730 Cr 50

* * * * * * * * * * * *

Fe 50

* * * * * * *

1200 1000 3600 300

*

Mg 50 270 310 460 1200 12000 550

*

4500 1350

*

1000

*

Ni 50

* *

150

*

760

* *

1500 560 590

* *

K 50 300 200 600 200 400 1800 300 1500 8100 300 200 250 Na 50 1400 1200 6000 6200 750 6800 1200 1900 50000 1200 400 1200 Area 1 Area 2 Area 3 Area 4 Metal wipe test results

ng/cm2

Contamination identification:

VPD ICP-MS

Element DL E10 at/cm2 Al 0.3 250 Ca 0.3 110 Cr 0.2 24 Cu 0.05 0.82 Fe 0.05 86 Mg 0.1 61 Ni 0.05 0.7 K 0.3 40 Na 0.3 77 Zn 0.1 13 300mm Wafer

VPD ICP-MS Results

BULK CONCENTRATION (atoms/cm3) Element Ceramic A Ceramic B Ceramic C Ba 3.0E16 9.1E15 2.2E13 B 1.2E18 1.7E16 6.3E15 Ca 1.1E19 9.1E17 6.6E15 Co 8.6E14 1.2E13 2.4E13 Cu 6.1E15 2.1E16 1.7E13 Fe 1.6E17 2.9E16 3.8E15 Li 3.3E16 1.2E15 ND Mg 7.7E16 1.8E17 3.4E15 Mn 3.1E15 2.8E15 7.5E13 Ni 1.7E16 1.0E15 3.4E13 K 1.8E18 1.0E17 4.4E14 Na 5.3E18 1.1E18 3.5E15 Sr 8.8E15 2.8E15 1.7E13 Sn 2.8E15 1.4E13 1.1E13 Ti 1.2E19 7.4E15 1.1E15 W 6.1E15 5.0E14 5.0E13 Zn 2.0E16 1.1E18 1.4E15 Zr 7.7E15 6.0E16 4.0E13

SARIS (10 µm) of ceramic insulator rods

Partitioning Tests

Partitioning test: metal wipe test
Hypothesis: micro-arcing

SLIDE 7

Reducing Contamination

Starting Materials Characterization

RED: material that may outgas

Part Description Material/Composition Cable Coaxial Conductor Material: Silver Plated Copper Covered Steel (SPCCS); Insulation Material: Tetrafluoroethylene (TFE); Outer Shield Material: Silver Plated Copper; Outer Jacket Material: Fluorinated Ethylene Propoylene Connector for Coaxial Plug Shell: Brass; Plug Body: Brass; Cable Clamp, Inner Sleeve, Washer or Nuts: Brass; Male Crimp Contacts: Bronze; Female Crimp Contacts: Bronze Connector for Coaxial Plug - 50 Ohm Outer Shell: Brass, Stainless Steel, Aluminum Alloy, PEEK; Sealing Resin: Epoxy; Grounding Crown: Bronze, Beryllium Copper, Stainless Steel; Latch Sleeve: Special Brass, Stainless Steel; Locking Washer: Bronze; Hexagonal or Round Nut: Brass, Stainless Steel, Aluminium alloy; Other Metallic Components: Brass, Stainless Steel; O-Ring and Gaskets: Silicone Cable Coaxial Conductor Material: Silver Plated Copper Covered Steel; Insulation Material: Tetrafluoroethylene (TFE); Outer Shield Material: Silver Plated Copper Covered Steel; Outer Jacket Material: Fluorinated Ethylene Propylene Connector Socket, Open End Contact Material: Copper Alloy; Contact Underplating: Nickel; Insulation Material: Glass Filled Polyester (PBT) Sensor, Light/Dark Materials: Polybutylene Phthalate (PBT); Cover: Polycarbonate; Emitter: Polycarbonate Wire, 28 AWG, Black * Conductor Material: Silver Plated Copper; Insulation Material: Tetrafluoroethylene (TFE) Connector, Socket 26 Position, Open End Contact Material: Copper Alloy; Contact Underplating: Nickel; Insulation Material: Glass Filled Polyester (PBT) Shrink Tubing, 3/32 ID, Kyanr, Clear Polyvinylidene Fluoride Wire, 28 AWG, Black * Conductor Material - Silver Plated Copper, Insulation Material: Fluorinated Ethylene Propylene (FEP) Cable, High Voltage, 22 AWG, Stranded Silver Plated Conductor, Overlapping tapes of GoreTM Corona Resistant (PTFE) Terminal Ring, 12-10 AWG Electrolytically Refined Copper

Organic outgassing sources

SLIDE 8

Reducing Contamination

Bulk Organic Characterization

Thermal Desorption Gas Chromatography Mass Spectrometry (TD-GCMS)

_ _ _

Carrier Gas Inlet Hot Sample Tube (400OC) Cold Trap Carrier Gas Inlet GC Analytical Column To Mass Detector

Primary (Tube) Desorption

Desorb Flow In-instrument outgassing

Tenax tube For medium to high outgassing material

Off-line outgassing

Quartz tube Larger sample to increase detection limit For low outgassing material

SLIDE 9

Reducing Contamination

Surface Cleanliness of Tool Components

Target contaminants depend on the history of the part

Starting material

Gross contamination Not a concern as the material will be machined and later cleaned Bulk contamination is more critical

Machined part

Major contamination is from machine oil, metal cross-contamination, water and solvent residue, oven, etc. Machine shops are not semiconductor clean environments Contaminants of concern: Organic > Particle > Metal > Anion

After Precision cleaning

Minor contamination Typically from handling, environment, packaging, etc. Contaminants of concern: Metal > Particle > Organic > Anion

Trend is for machine shops to pre-clean in-house,

utsource

Precision Cleaning and send parts directly to the custom er

a) Precision cleaning is defined as “The removal of undesirable contaminants

to a pre-determined measurable standard without introducing new contaminants or changing the surface integrity”

b) Precision cleaning dictates the tool BOM must have a cleanliness

specification

SLIDE 10

Reducing Contamination

Surface Contamination Characterization

Application

Machined parts – coupons and first article New and used parts after Precision Cleaning

Specification

Effective in removing surface contamination for analysis Must be damage-free with minimal material loss Performed on small and large parts (300mm and 450mm) Part may be returned to the field after testing

Current test methods involving wet chemistry

Imparts minimal damage to the surface No restriction on part size Effective in removing metals, anions and organic residues since they have a high solubility in liquid chemistries High efficiency in particle removal

Adjusting the surface zeta potential (e.g. pH) to reduce the adhesion force
Reducing megasonic energy to improve the particle removal performance and to

reduce damage

SLIDE 11

Reducing Contamination

Chemical Surface Characterization

KEY

1. Metal: whole surface extraction
2. Metal: UPW extraction efficiency less than using acid
No surface damage
3. Metal: localized surface extraction using acid
Can be performed directly on tool component surface
4. Organic: solvents to extract organic residue and UPW/TOC
5. Organic: weight of NVR and organic identification
6. Ionic: whole surface extraction
7. Particle: whole surface particle counting and identification

Test methods are often referred to as Leach or Extractable

Acid extraction & ICP-MS

1

UPW extraction & ICP-MS

2

Drop scan etch & ICP-MS

3

Solvent extraction & GC-MS

4

Solvent extraction & NVR/FTIR

5

Ionic UPW extraction & Ion Chromatography

6

Particle UPW extraction & LPC (SEM-EDS)

7

Metal Organic

SEMICONDUCTOR PROCESS OPTIMA Wafer Production Thermal Oxidation/Film Photolithography Etch Doping/Ion Implant Dielectric Deposition CMP

Non- Destructive test procedures

Ceramic showerhead

8”

SEM with large sample chamber

SLIDE 12

Reducing Contamination

Surface Extraction of Components

Provides surface cleanliness verification and quantification of contaminants

Compare vendors Qualify components to a cleanliness specification Ensure components and coatings are compatible to a process – temp, exposure time, acid/alkali, HV, etc. Lot to lot quality control

General rule

A less aggressive leach results in lower detectable contaminant level A more aggressive leach results in higher detectable contaminant level

Static leach conditions

Component is soaked in UPW or chemical solution Standard test condition

Ambient temperature, UPW and short extraction

time of 1h to 1 day

Semi-Aggressive

Elevated temperature <50C, UPW and short

extraction time of 1-2h

Aggressive

High temperature, extended extraction time and/or use of chemicals
Chemical for 7 days at ambient temperature
UPW at 85C for 7 days (SEMI F-57)

Ceramic rings

SLIDE 13

Reducing Contamination

Surface Extraction of Packaging Films

Rule of thumb, the cleanliness level of packaging films should be at least

3-5x lower than the cleanliness specifications of the parts to be packaged

Natural and antistatic PE generally exhibit acceptable levels of ionic cleanliness;

generally shown to also be oil and amine-free

Most available films, including natural PE, are not adequate for packaging tool parts

requiring very low levels of hydrocarbon contaminants. FEP is acceptable but costs 15x more than PE.

Bagging requirements:

Double bagging for all parts except tool parts (robotic blades, handling systems, chucks) that are exposed to the wafer must be triple bagged Bagging material must cover all outer tool surfaces

10 50 40 30 20 Ionic Species F

Cl
NO3
SO4
Na

+

NH4

+

K

+

Mg

2+

Antistatic PE Natural PE Antistatic Nylon

Ca

2 +

Lin S and Graves S, Micro, October, 1998

S u r f a c e C

n

c . ( x 1

12

m

l

/ c m

2

)

SLIDE 14

Reducing Contamination

Metal AES

1

TXRF

2

VPD ICP-MS

3

SurfaceSIMS

4

TOF-SIMS

5

Organic Full Wafer Outgassing TD-GCMS

6

TOF-SIMS

7

XPS

8

Ionic XPS

9

Particle FE-AES

10 SEMICONDUCTOR PROCESS OPTIMA Wafer Production Thermal Oxidation/Film Photolithography Etch Doping/Ion Implant Dielectric Deposition CMP

Physical Surface Characterization

KEY

1. AES: 30-50Å, at% DL, elemental survey, conducting surface
2. TXRF: 30-50Å, 109-1015 at/cm2, elemental survey, flat surface
3. VPD ICP-MS: SiO2, 107-1015 at/cm2, elemental survey
4. SurfaceSIMS: any depth, 108-1015 at/cm2, elemental specific
5. TOF-SIMS: ML, 107-1015 at/cm2, elemental survey, any surface
6. Full Wafer Outgassing: ng/cm2, organic survey
7. TOF-SIMS: monolayer, ng/cm2, organic survey, any surface
8. XPS: 30-50Å, at% DL, elemental/chemical state survey,

non-conducting surface

10. FE-AES: 10nm spatial resolution for elemental characterization

Other

UV (black) light: visual inspection for residue polymer on the surface
Profilometry: surface roughness and surface layer thickness (Fisherscope)

Destructive techniques * non-destructive

wafer test

*

Mostly used for coupons, wafers and R&D

Sectioning ceramic showerhead

* *

X-section of opening

SLIDE 15

Reducing Contamination

Tool Particle Specification

Wafer Front Sidea Wafer Back Sidea Tool Surfaceb >90 nm 90 nm 65 nm 45 nm Full pipeline test, 6 wafers, 150 cycles, KLA SP2 Particle Specification Technology Node Analytical Test Non-Critical Surface ≤10/in2 @ 0.3 µm Critical Surface ≤1/in2 @ 0.3 µm 0.2 @ 90 nm (0.0002/cm2 pwp) Full Contact <1500 @ 90 nm (2.8/cm2 pwp) Low Contact <500 @ 90 nm Edge Contact <20 @ 90 nm

a) Tool with closable holes for insertion of sample heads for airborne qualification purposes and FA b) Particles on tool component surfaces and skin shall be measured using a surface particle detector

Mainframe Surfaces (particles/in² @ 0.3 µm) Painted = <10-80 Granite = <10-95 Anodized = <10-60 Aluminum = <15-90 Plexiglass = <10-90

Location Area 0.3 um 0.5 um 1 um 5 um 10 um Chamber lid 15 0.04 Chamber lid 16 0.04 Location Area 0.3 um 0.5 um 1 um 5 um 10 um Chuck/back 10 0.08 Chuck/front 11 Stage/rear 12 0.21 0.13 Stage/front 13 0.08 Nest/low surface 6 0.17 0.13 0.08 Nest/high surface 7 0.13 0.08 Transfer arm/front 8 0.04 0.04 0.04 Transfer arm/back 9 0.88 0.79 0.58 Location Area 0.3 um 0.5 um 1 um 5 um 10 um Off LL 1 0.21 Bridge 2 6.92 3.54 1.6 0.08 0.04 Front LL 3 2.38 1.83 0.96 0.42 0.33

1 2 3 4 5 8 9 1 0 1 1 1 3 1 2 1 5 1 6

The Al/Ti particle originating from an

interaction of an etch by-product of the TiN adhesion layer and the process chamber hardware

Ti Al Si

SLIDE 16

Reducing Contamination

Tool Metal Specification

Technology Node Analytical Testa Metal Specificationb Full Pipeline test, 6 wafers by 100 cycles >90 nm VPD-ICP-MS ≤5E11 at/cm2 per metal 90 nm VPD-ICP-MS ≤1E10 at/cm2 per metal 65 nm VPD-ICP-MS ≤1E10 at/cm2 per metal 45 nm VPD-ICP-MS ≤5E9 at/cm2 per metal

a) VPD ICP-MS detects Ca, K, Na, Al, Fe, Cr, Ni, Zn, Li, Be, Mg, V, Mn, Co, Ga, Sr, Zr, Mo, Cd, Sn, Sb, Ba, Ti, Y, Rb, In, Ce, Th, U, Cu. b) Target metals include Gp 1 metals (Fe, Ni, Cu, Cr, Co, Hf, and Pt; can dissolve in Si and form silicides) and/or Gp 2 metals (Ca, Ba, Fe and Sr; GOI killers)

SIMS PROFILE

STANDARD TXRF

=

SurfaceSIMS TOF High Detection Low Detection Wafer SARIS Gross Contamination Process Tool

Uncleaned Cleaned

Metal

SLIDE 17

Reducing Contamination

Tool Organic Specification

a) ASTM F1982-99 "Standard Test Method for Analyzing Organic Contaminants on Silicon Wafer Surfaces by TD-GC.“ This method is designed to sample semivolatile organic airborne molecular contamination adsorbed onto the polished face of the Si wafer b) Wafer side specific c) >10 ng/cm2 affects adhesion

2 ng/cm2 ˜ 0.1 ML
ML ~5Å
ML ~ 1015 at/cm2

Technology Node Analytical Testa Organic Specificationb, c, d Organic component Sum ≥C7 tested in Dynamic Mode >90 nm ≤20 ng/cm2 90 nm ≤20 ng/cm2 65 nm ≤15 ng/cm2 45 nm ≤10 ng/cm2 1) Load Lock Partition test: 1x2 wafers, 200 cycles (100 cycles each), ~ 30 mins exposure/wafer. 2) Organic Pipeline test: 2x2 wafers, 120 cycles (30 cycles each), ~20 mins exposure/wafer. 3) Full wafer outgassing by TD-GC-MSa

SEMI MF1982-1103 Full wafer outgassing TD GC-MS

Figure 1 Sample ID: CHUCK- Al 2O3, 1/22/07 (19:00 HOURS AT 1.2 x 10

7 TORR)

5.00 10.00 15.00 20.00 25.00 30.00 35.00 2000000 4000000 6000000 8000000 1e+07 1.2e+07 1.4e+07 1.6e+07 1.8e+07 2e+07 2.2e+07 2.4e+07 2.6e+07 2.8e+07 3e+07 3.2e+07 3.4e+07 3.6e+07 3.8e+07 4e+07 4.2e+07 4.4e+07 4.6e+07 4.8e+07 5e+07 Time--> Abundance Ion 33.00 (33.00 to 700.00): 70052605.D d 8

T

O L U E N E ( I N T E R N A L S T A N D A R D ) C 8

H

Y D R O C A R B O N S C Y C L O ( M e

2

S i O )

3

C Y C L O ( M e

2

S i O )

4 +

E T H Y L H E X A N O L C Y C L O ( M e

2

S i O )5 F L U O R O A L K Y L E T H E R ( m / z : 6 9 , 1 1 9 , 1 6 9 , 2 8 5 , 3 3 5 ) C Y C L O ( M e2 S i O )

6

C Y C L O ( M e

2

S i O )7 C Y C L O ( M e

2

S i O )8 C Y C L O ( M e2 S i O )

9

C Y C L O ( M e

2

S i O )

1

C Y C L O ( M e

2

S i O )

1 1

P O S S I B L E C Y C L O ( M e2 S i O )1

2

Figure 1 Sample ID: CHUCK- Al 2O3, 1/22/07 (19:00 HOURS AT 1.2 x 10

7 TORR)

5.00 10.00 15.00 20.00 25.00 30.00 35.00 2000000 4000000 6000000 8000000 1e+07 1.2e+07 1.4e+07 1.6e+07 1.8e+07 2e+07 2.2e+07 2.4e+07 2.6e+07 2.8e+07 3e+07 3.2e+07 3.4e+07 3.6e+07 3.8e+07 4e+07 4.2e+07 4.4e+07 4.6e+07 4.8e+07 5e+07 Time--> Abundance Ion 33.00 (33.00 to 700.00): 70052605.D d 8

T

O L U E N E ( I N T E R N A L S T A N D A R D ) C 8

H

Y D R O C A R B O N S C Y C L O ( M e

2

S i O )

3

C Y C L O ( M e

2

S i O )

4 +

E T H Y L H E X A N O L C Y C L O ( M e

2

S i O )5 F L U O R O A L K Y L E T H E R ( m / z : 6 9 , 1 1 9 , 1 6 9 , 2 8 5 , 3 3 5 ) C Y C L O ( M e2 S i O )

6

C Y C L O ( M e

2

S i O )7 C Y C L O ( M e

2

S i O )8 C Y C L O ( M e2 S i O )

9

C Y C L O ( M e

2

S i O )

1

C Y C L O ( M e

2

S i O )

1 1

P O S S I B L E C Y C L O ( M e2 S i O )1

2

Cyclo(Me 2SiO) Cyclo(Me 2SiO) Fluroalkylether Fluroalkylether Fluoroalkyl Ether

RGA

Cyclo( Me 2SiO)3 Cyclo( Me 2SiO)5 Cyclo( Me 2SiO)6 Cyclo( Me 2SiO ) 7 Cyclo( Me 2SiO ) 8 Cyclo( Me 2SiO)

1 0

Cyclo( Me 2SiO ) 1 2 Cyclo( Me 2SiO)4

+ Ethyl Hexanol

Cyclo( Me 2SiO)9 Cyclo( Me 2SiO)

1 1

Full Wafer TD-GCMS

SLIDE 18

Reducing Contamination

Tool Escalation Case Study

TOOL ESCALATI ON TOOL OBSERVATI ONS FAI LURE ANALYSI S ROOT CAUSE REMEDY

High SMC carbon level exceeding tool acceptance level of 2 at% by XPS 7 carbon at% on witness wafer Full Wafer TD-GCMS to identify AMC-MC species. FTIR and TOF-SIMS to identify lubricant compound. Excess lubricant in tool Remove excess lubricant High Cl TXRF level exceeding 5E10 at/cm2 spec for acceptance 5E13 Cl at/ cm2 on witness wafer Determine inorganic Cl using IC or organic Cl using

GCMS. O-Cl confirmed

followed by species identification using Full Wafer TD-GCMS in dynamic testing mode. Foam isolation pads TD-GCMS verification

f alternative

materials High Pb level by VPD ICP-MS exceeding 5E10 at/ cm2 tool SPC 5E11 Pb at/cm2 on witness wafer VPD ICP-MS monitoring was critical as Pb is not detected by TXRF using W

source. Isolation

experiments identified root source. City water source used during manufacturing of PVDF tubing Hot DIW flush of tubing High replacement rate of beam aperture on ion implanter Reduced beam current SEM-EDX identifies organo- Si as contaminant on

aperture. TD-GCMS

identifies organic species. Outgassing of Gelpak aperture packaging TD-GCMS verification

f alternative

packaging

Metal spec is 5E10 at/cm2 by TXRF

1

Residual HCl from insufficient rinsing??

2

INORGANIC ORGANIC SARI S/ SEM- EDX First “look” t ool LOW CONC. VPD ICP-MS TXRF, VPD TXRF UPW – IC UPW-ICP-MS dAcid-ICP-MS TOF-SIMS Quad-SIMS LOW CONC. TOF-SIMS FW TD-GCMS TD GC-MS

4

Static wafer show no Cl by TXRF Dynamic wafer testing show Cl

3

Pad compresses and

utgasses at edge

6

Blue pad outgass Blk pad not outgas

7

Cl

Flame retardant

5

This is a difficult problem to solve because no one did anything wrong. In fact, everyone involved did what they thought was the right thing to expedite the PM and keep on schedule.

8

SLIDE 19

Reducing Contamination

Organic Tool Optima™

Escalation

Performance
Contamination

>2 at% carbon (XPS) >5E10 Cl atoms/cm2 (TXRF)

Partitioning Test

Select materials, inside and
utside of the tool, to test for
rganic outgassing

Identify and quantify

rganic species
Wipe test for local testing of tool

components

Contamination Identification

SMC-SMOrg - FW TD-GCMS

Static: 2 to 24 h exposure Dynamic: 20 to 100 cycles Identifies and quantifies organic species Ranks organic concentrations into groups – low (C7-C10), medium (>C10 – C20) and high boilers (>C20)

Resolve Escalation

Repeat performance or

contamination test

Verify Root Cause

Repeat static or dynamic

wafer exposure

Perform FW TD-GCMS

SLIDE 20

Reducing Contamination

Conclusion

Tool contamination is a major cause of many fab escalations High yield processing requires clean tools and clean manufacturing

procedures. This dictates there must be cleanliness specification for in-tools,

precision cleaning, packaging and on the process floor (Ex: housekeeping cleanliness specifications)

Unfortunately, cleanliness specifications are often lacking and this impounds

the difficulty to resolve contamination escalations, both in the tool and on the process floor

Bulk and surface contamination of starting material and tool components are

equally important

Target contaminants differ for a part and depends on its life cycle – from raw

material, coupon, first article, new part, used part, etc.

Non-destructive chemical characterization is possible on production tool parts Destructive physical characterization on production tool parts is an option if you

are willing to sacrifice the part

Cleanliness verification of tool BOM is instrumental to optimizing process

yields. Advanced technology node processes require stringent cleanliness