New electrostatic dissipative plastic materials for cleanroom applications

37th R3 Nordic Symposium, Tampere, May 29-31, 2006

New electrostatic dissipative plastic materials for cleanroom

applications

Dr. Antti Helminen, R&D Manager &Mr. Peter Ristikangas, Product Group Manager

Premix Oy, Finland


New electrostatic dissipative plastic materials for cleanroom applications

Content:• Overview of Premix• ESD-materials; conductive vs. dissipative• Carbon alternative• ICP – Panipol• IDP polymers

– Structure– Properties– Applications



Where you can find us?

Premix Thermoplastics Inc.

(US)

Algol ChemicalsOy

(EE, LV, LT)A. Westensee und Partner GmbH

(DE, AT)

Interpolymer AG(CH)

Paceco Ind. Supplies Pte(SG, CN, MY, ID)

Taiwan Kwang Cheng Ltd.(TW)

P.S.D.Pty Ltd(AU, NZ)

D.E.Plus Marketing(IL)

Goldaplast s.a.s.(IT)

Polymix(FR)

SMI bvba(Benelux)

Cornelius Chemicals Co.(GB, IE)

Teknisk Agentur A/S(DK)

Bröste AB(SE, NO)

Vamptech(ES)

Koehl&Borkelmans

(BE)

Flamingo Marketing Co.(IN)

Premix Oy(FI)


Premix briefly

Premix is a leading developer, marketer and manufacturer of conductive plastics.

Our product range covers virtually the whole resistivity spectrum offering solutions from the dissipative ESD polymer compounds to highly conductive EMI-shielding materials.


Premix product groups

• Electrically Conductive Plastics– PRESEAL® - highly conductive TPE – PRE-ELEC® EMI - highly conductive

engineering thermoplastics– PRE-ELEC® - carbon black compounds– PRE-ELEC® ESD - IDP compounds

• Marketing for – PANIPOL® - ICP compounds


Why use plastics?• Good processability (in 3D shapes)

– Suitable for mass production• Wide range of properties available• Light weight• Low price

• Good insulative properties as such→ Conductive path by either conductive fillers or

conductive polymers is required


Resistivity spectrum


Why ESD protection?

• ElectroStatic Discharge• In electronics production components can

be very easily damaged• Sparks can even cause explosion• There needs to be a route for charges to

discharge in a controlled manner


Perfect ESD material has…

• Controlled ESD properties: The material should be dissipative

• Clean: No ions, particles or gases should come off the material, abrasion resistance

• Permanent: Cleaning and washing should not affect the dissipative properties

• Stable: Humidity should not affect the performance


ESD materials classification1. Conductive materials:

Surface resistance (IEC 61340-2-3) 10² < Rs < 105 ΩVolume resistivity (ESD STM 11.12) ρv < 105 Ωm.

2. Dissipative materials (typical EPA-area materials):Surface resistance (IEC 61340-5-1) 106 < Rs < 109 Ω

3. Low-Charging materials (Antistatic):Surface resistance (IEC 61340-5-1) 109 < Rs < 1011 ΩStatic decay < 10 s (RH 12%) and < 2s (RH 50%)

4. ESD-Shielding materials:Discharge shielding (ESD STM 11.13) Energy E < 50 nJ

Note ! All values must pass in RH 12% and RH50%, Temp. 23°C conditions.


Functionality of dissipative materials

• In low charging materials the functionality is more important than the resistivity value

• Static decay is the key • For static decay to occur

there needs to be proper grounding


Carbon alternative (1/2)• Typical carbon black compounds give VR:

<104 Ω·cm, SR: <105 Ω• Dissipative Blacks with SR 106 – 109 Ω

– HDPE: PRE-ELEC® PE 1295 – PP: PRE-ELEC® PP 1395

• Permanent, no humidity dependent

• Sloughing is the mainchallenge


Carbon alternative (2/2)


ICP - Panipol®• Inherently Conductive Polymers• Panipol’s polyaniline compositions• Panipol compounds

have SR of 106–109

Ω typically• Migration of additives

is the main challenge


IDP compounds (1/3)• SR: 108-11 Ω typically• Permanent antistatic effect• Can be colored• Transparent grades available

• Some humidity dependency (in extreme conditions)

• Leachables can be a problem in clean room environments

• More expensive than CB-compounds


IDP compounds (2/3)Are made of• Inherently Dissipative Polymer (block copolymer)• Salts (typically Li+, K+)• Bulk plastic (PE, PP, PS, ABS…)

• Ions are responsible for charge transfer, not the electrons in conjugated carbon double bonds

• Percolation is needed– Interpenetrating phase structures– Cocontinuous phase structures


IDP compounds (3/3)

Cleanliness data


Cleanliness Property

Test Method Test Conditions

Test Results

Organics total Dynamic HeadspaceGC/MS Analysis 85°C, 3 hr <3.0 µg/cm2

Ionics - cationsLithiumSodiumAmmoniumPotassiumMagnesiumCalsium

Ion Chromatography Analysis 85°C , 1 hr

ND<0.30 µg/cm2

<0.002 µg/cm2

<0.05 µg/cm2

ND<0.003 µg/cm2

Ionics - anionsFluorideChlorideNitriteBromideNitratePhosphateSulfate

Ion Chromatography Analysis 85°C , 1 hr

<0.005 µg/cm2 <0.02 µg/cm2

NDND<0.005 µg/cm2

ND<0.01 µg/cm2

Non Volatile Residue (NVR) IPA extraction <20 µg/cm2

Silicones, phtalates FT-IR ND

ND = not detected, data for PRE-ELEC® TP 8223


PRE-ELEC® ESD• Carrier resins ranging from

– HDPE, LDPE, PP– HIPS– ABS (V0, transparent)– PC/ABS, PC/PBT

• SR: 108-11 Ω typically


Co-extrusion is often the most cost-effective solution

• Dissipative / insulative / dissipative• Dissipative / conductive / dissipative• Insulative / dissipative / insulative


Static dissipative plastics

• Mainly for ESD controlSome other useful characteristics• Less particulate contamination due to ESA

(ElectroStatic Attraction)• Electrostatic painting• Printability…


New electrostatic dissipative plastic materials for cleanroom applications

Final remarks:• Electrostatic dissipative plastics are needed for ESD

protection in electronics manufacturing• CB compounds typically too conductive for this

application• PRE-ELEC® dissipative blacks• PANIPOL® DX and CX: ICP compounds• PRE-ELEC® ESD: IDP compounds• Differences in resistance level, in properties such as

color, cleanliness, and in price


THANK YOU!

Documents

New electrostatic dissipative plastic materials for cleanroom applications