Surface Cleanliness Martin Derks www.golighthouse.com 1
Contamination Monitoring Solutions: Contamination: "Any foreign material or energy that has a detrimental effect on a product or process Monitoring Solutions for: Particles Airborne Molecular Contamination Electrostatic Charge Electrostatic Discharge EMI Humidity Temperature Pressure Air Velocity Vibration Colony Forming Units TOC,pH, Resistivity And more www.golighthouse.com 2
Headquarters: Fremont, CA Medford Research and Development Engineering Pilot Production Executive Management Fremont www.golighthouse.com 3
Lighthouse Benelux Boven Leeuwen www.golighthouse.com 4
How Clean is Clean "how clean is clean in relation to given parameters? "how clean is clean enough? "how clean are the results of one cleaning process compared to another cleaning process?" www.golighthouse.com 5
Particles Solid aerosol particles are all around us. www.golighthouse.com 6
Distribution of Aerosol Particles >20µm = Gravitational influence dominates N/ log(d) = 24.0d -3.08 <0.1µm = Electrostatic attraction and diffusion dominates www.golighthouse.com 7
Optical Particle Counting Particle Counter ANNO 1880 www.golighthouse.com 8
OK monitoring systemen www.golighthouse.com 9
21-10-2008 00:05:23 21-10-2008 01:45:23 21-10-2008 03:25:23 21-10-2008 05:05:23 21-10-2008 06:45:23 21-10-2008 08:25:23 21-10-2008 10:05:23 21-10-2008 11:45:23 21-10-2008 13:25:23 21-10-2008 15:05:23 21-10-2008 16:45:23 21-10-2008 18:25:23 21-10-2008 20:05:23 21-10-2008 21:45:23 21-10-2008 23:25:23 Activiteiten. Alarmering? 1800000,0 1600000,0 1400000,0 1200000,0 1000000,0 800000,0 OK 8 0,5 micron Alarm 600000,0 400000,0 200000,0 0,0 www.golighthouse.com 10
20-10-2008 00:05:23 20-10-2008 18:35:23 21-10-2008 13:05:23 22-10-2008 07:35:23 23-10-2008 02:05:23 23-10-2008 20:35:23 24-10-2008 15:05:23 25-10-2008 09:35:23 26-10-2008 03:05:13 26-10-2008 21:35:13 27-10-2008 16:05:13 Schoonmaak probleem. Alarmering? OK 8 5,0 micron 140000,0 Deeltjes 5,0µm 120000,0 100000,0 80000,0 60000,0 OK 8 Inleiding 5,0 micron 40000,0 20000,0 0,0 www.golighthouse.com 11
Deeltjesneerslag Afmeting in µm Gemiddelde valsnelheid ronde deeltjes in stilstaande lucht Valsnelheid in mm/s Valtijd over 1 m tijd 0.5 0,01 25 uur 1 0,04 8 uur 5 0,7 25 min 10 3 6 min 20 12 83 sec 50 75 13 sec 100 300 3 sec www.golighthouse.com 12
Deeltjes depositie vs Oppervlakte reinheid DDK Deeltjesdepositie klasse DDK is de toename van het aantal deeltjes per dm² per uur op een testoppervlakte Als basis voor de klasse is 1µm gekozen DDK is hulpmiddel om risico van contaminatie doorneerslag van deeltjes te bepalen: RISICO: = bloodstellingstijd DDK 100 betekent: 10 deeltjes >10µm per dm² per uur 2 deeltjes >50µm per dm² per uur 1 deeltje> 100µm per dm² per uur www.golighthouse.com 13
Relative Size Micron Scale 50 40 30 20 10 1 Andenovirus 0.075 Micron Virus 0.1 Micron Human Blood Cell 7 Micron E-Coli 0.5 Micron Human Hair 50-100 Micron 35 Micron Visible Particles www.golighthouse.com 14
Relative Size Gas Molecules (AMC) 2-50 Å (.0002-.005µm) 0.3 µm particle 0.1 µm particle www.golighthouse.com 15
Personeel als grootse Vervuiler 5 tot 10 miljoen huidcellen per dag (30 gram) 2300 micro-organisme per cm² 25µm vallende deeltjes 5µm zwevende deeltjes Tussen 5µm en 25µm overgangsgebied www.golighthouse.com 16
Surface Testing Methods: Non-Standard Surfaces Some Surfaces May Be Located in Hard to Reach Areas Some Parts May Be Too Small Alternate Testing Methods May Be Used 1. Tape Lift 2. Part Rinse www.golighthouse.com 17
Deeltjes Depositie Klasse www.golighthouse.com 18
Surface Particle Cleanliness Class ISO14644-9 SPC www.golighthouse.com 19
Witness plates Deposited particles can have a greater impact on high-technology manufacturing processes than airborne particles. A witness plate is a flat, particle-free object made from the same materials as the product being manufactured (for example: if you make ABS plastic products, you should use ABS plastic witness plates). www.golighthouse.com 20
wafer inspection system > 0,1µm www.golighthouse.com 21
PartSense: Portable System > 2,0µm www.golighthouse.com 22
Measuring Principle: Technique Illumination with Glancing Light Fading out the rough surface Imaging of the Particles Using Optics Image Recording Using a Digital Camera Analysis of the Images Using Digital Image Processing www.golighthouse.com 23
Measuring Principle > 25µm www.golighthouse.com 24
Surface Cleanliness qualification method GSA 07 4320 Grade 4 cat. 1, 2 & 3 UV-A Blacklight inspection GSA 07 0012 www.golighthouse.com 25
Fluorescentie UV light source Camera Filter λ 375nm λ 400/500 nm www.golighthouse.com 26
Application area : Grade 1, 2, 3, and 4 Measurement area : 100 x 100 mm Every surface / substrate can be measured, except fluorescent one s. ( only when the tool can be placed correctly, stray light should be eliminated! ) Roughness / reflectivity of the substrate is not an issue. www.golighthouse.com 27
Functionality : P.A.C. ( Percentage of Area Covered ) Size of the individual fluorescent particle s on the surface Number of fluorescent particle s on the surface. Length and width of the individual fluorescent particles Measurements are reproducible Ability to do a qualitative check of a surface s particle contamination and have immediate feedback OK or NOK www.golighthouse.com 28
UV Surface Particle Counter - Produced by Lighthouse - Developed by ASML Only UV (λ 375nm) fluorescent particles / fibers can be seen with the tool. (range is 400 / 900 nm light ) www.golighthouse.com 29
Substrate is a Circuit Board with Components. www.golighthouse.com 30
Circuit Board with Components, Detail from previous slide. www.golighthouse.com 31
Product surface = 1 dm 2 Specification = 4 particles/dm 2 Product 1dm 2 R Q no action required Cleaning needed 4 particles/dm 2 6 particles/dm 2 www.golighthouse.com 32
GSA 07 4320 vs Area size Product surface < 1 dm 2 Specification = 4 particles/dm 2 Product 0.5 dm 2 1dm 2 Calculation = amount of detected particles x (1 dm 2 / product area) eg 6 = 3 X (1/0.5) = 3 X 2 R Q no action required Cleaning required 4 particles/dm 2 6 particles/dm 2 www.golighthouse.com 33
GSA 07 4320 vs Area size Product surface > 1 dm 2 Specification = 4 particles/dm 2 Product 4 dm 2 1dm 2 R no action required 4 particles/dm 2 www.golighthouse.com 34
GSA 07 4320 vs Area size Product surface > 1 dm 2! Specification = 4 particles/dm 2 Product 4 dm 2 1dm 2 Q R CLEANIN G NEEDED! www.golighthouse.com 35
Particle Fallout prediction Particle deposition on critical surfaces affect the functionality of ASML scanners.. The simple mechanism of PFO spread at ASML cleanrooms: Production Activities Particle generation Airborne contamination N c (particles/m 3 ) Time & Space dependent deposition PFO rate ṅ (particles/m 2 /time) The project involved experimental modeling of this mechanism to establish a relationship between N c and ṅ of the form shown below: n( x m,t) (N c) t (Distance) www.golighthouse.com 36
Dust feeder witnesswafers Particle Counters 0,1µm www.golighthouse.com 37
Surface Particle Counter www.golighthouse.com 38
50µm Particles Vezel www.golighthouse.com 39
Resultaat metingen: - DNK (Deeltjes Neerslag Klasse) - ORK (Oppervlakte Reinheid Klasse) - Deeltjeslijst ( positie deeltje en eigenschappen) - Aantal deeltjes per klasse www.golighthouse.com 40
Surface Particle Probe Counter www.golighthouse.com 41
www.golighthouse.com 42
Thank You www.golighthouse.com 43