Wafer Level Packaging EKC162 Photoresist & PI/PBO Remover Date WLP Remover V1.5
Assembly Board One DuPont Solution CooLam TM Kaptone Thermo conductive/ Thermal resistant Substrate system Packaging & Assembly Wafer Process Substrate Polyimide (Buffer/PKG) Polyimide (Stress buffer) P-SiN (Passivation) Cu Via Bump Solder/Au (Solder) Ball BPR(Cu) Low-k dielectric W Via Underfill Cu wiring Cu Via TEOS APL/WB series Dryfilm photoresist EKC WLP Removers - DryFilm - HDMS PI/PBO - Liquid resist HDMS series Photo sensitive Polyimide coatings Vertrel CF deposition Cleaning agents Ventral CMP slurry STI, IMD (Ceria) Gate, Barrier metals Cu, W (Colloidal Silica) EKC Cleaners and Removers Post Etch Residues removers for - Al -Cu / Low-k - Metal gate & High-k Cleaners for - Cu / W post CMP Syton Mazin BG polish Wafer polish 2008 EKC Technology / DuPont Electronic Technologies 2
Typical Process flow for RDL using the One DuPont Solution Polyimide (Stress buffer) Spin on HDM Polyimide Polyimide (Stress buffer) Reflow and remove DuPont WBR Dry Film with WLP EKC162 Image and develop HDM Polyimide Plate seed layer Plate Bump Laminate image and develop DuPont WBR Dry Film 2008 EKC Technology / DuPont Electronic Technologies 3
Agenda Application Chemistry Compatibility Process Information Results Summary 2008 EKC Technology / DuPont Electronic Technologies 4
Application EKC162 is ideal for every WLP Remover/Stripping application. DryFilm and Liquid resist removal for: Au, Ni, Cu, PbSn, SnAg and high lead Bumps TSV Formation Stencil and electroplated bumps GaAs Backside Via application Full rework capability Removes uncured HD-4000 Series PI Compatible with normally cured HD-4000 Series and HD-8800 Series for wafer level & chip scale packaging 2008 EKC Technology / DuPont Electronic Technologies 5
Chemistry EKC s unique qualifications to provide a solution Formulation expertise Proven capability in the optimization of raw materials Years of experience working at interconnect levels with complex metal combinations A wealth of analysis and applications knowledge Quality systems geared to semiconductor level needs An established organization for worldwide support 2008 EKC Technology / DuPont Electronic Technologies 6
Chemistry Physical and Chemical Properties Property WLP EKC162 ph >14 Solubility in Water Complete Evaporation Rate <1 (Butyl acetate = 1) Flash Point ( C) >120 Boiling Range 120 135 C (248 275 F) Freezing Point ( C) - 24 C * Specific Gravity 1.0989 Vapor Density >1 (Air = 1) Appearance Clear liquid * Remover was left overnight at -24 C and did not freeze 2008 EKC Technology / DuPont Electronic Technologies 7
Compatibility Observations of surface condition and etch rates on typical wafer materials from the lab and from beta tests showed excellent compatibility n n n n n n n n High lead solder Eutectic solder Lead free solder (SnAg) Copper, Electroless Cu seed layer TiW/Cu/Au Cu/Ni Au Compatible with normally cured HD-4000 Series and HD-8800 Series for wafer level & chip scale packaging 2008 EKC Technology / DuPont Electronic Technologies 8
Compatibility Material Appearance Weight Change Metals Extraction EPDM Pass Pass Pass FEP Pass Pass Pass FRP Pass Pass Pass HDPE Pass Pass Pass Kalrez 8201 O-ring Pass Pass Pass PFA Pass Pass Pass Polypropylene (natural) Pass Pass Pass Polypropylene (white) Pass Pass Pass PTFE Pass Pass Pass PVC Pass Pass Pass PVDF Fail Pass Fail Simriz O-ring Pass Pass Pass Type 316 SS Pass Pass Pass Type 304 SS Pass Pass Pass Method: Samples of various materials were immersed in EKC162 to determine compatibility. Exposure time of the samples to the chemistry was 65 C for seven days. After exposure the samples were weighed and visually examined for signs of incompatibility. The stripping solution was also analyzed to confirm there were no significant changes in metals contamination. 2008 EKC Technology / DuPont Electronic Technologies 9
Compatibility 55 o C/20min HD-4000 Series PI on Cu Purpose: To evaluate the compatibility of EKC162 with HD-PI 4000 series partially cured at 250 C for 2 hours Experimental Results: Chemistry Temp ( C) Time (min) Observations EKC162 55 20 No PI attack Insignificant difference was observed between the processed and unprocessed microscopic images of HD-4000 Series. This indicates that out EKC162 is compatible with HD-4000 Series. Before After 55 C/20 minutes 2008 EKC Technology / DuPont Electronic Technologies 10
Compatibility 5. Test Results 55 o C/20min HD-8800 Series PBO on bare Si Optical Microscope X 50 X 200 1. No PBO appearance change and PBO crack. 2. No Solder PBO appearance change and PBO crack. 2008 EKC Technology / DuPont Electronic Technologies 11
6. PBO Compatibility Study Compatibility 55 o C/20min HD-8800 Series PBO on bare Si PBO samples: HD-8800 Series PBO Cured @300C 5um thickness films with patterns, attached to 6 Si wafers Measured @EKC (with Step Height Measurement) Initial After 55C, 20min After 55C,60min Thickness (um) 5.189 5.301 5.602 6 Thickness (um) 5.5 5 4.5 EKC162 4 0 20 40 60 80 Treatment time (min) Thickness gain (swelling) ratio of PBO was within 10% after 60min treatment @55C: 8%, 2008 EKC Technology / DuPont Electronic Technologies 12
Process Information Typical Semitool SST Process Recipe Step Time RPM Process Source Manifold Drain 1 0:05 35 Warming-up Chamber - Chm 1 2 0:10 35 WLP EKC162 TM to drain T1 M1 Chm 1 3 0:05 35 Delay to drain Chamber - Chm 1 4 30:00 35 WLP EKC162 TM reclaim to reclaim T1 M1 T1 5 0:10 500 N2 purge to reclaim N2 M1 T1 6 0:05 500 Chamber to drain Chamber - Chm 1 7 2:00 50 DI water rinse to drain CDIW M1, M2 WD1 8 3:00 500 DI water rinse to drain CDIW M1, M2 WD1 9 0:30 1200 N2 dry/purge N2 M1, M2, M3 WD1 10 5:00 600 N2 dry/purge N2 M3 WD1 Temperature: 50 C Flow Rate: 1.5 gal/min 2008 EKC Technology / DuPont Electronic Technologies 13
Process Information Process Recommendations for Wet Bench Strip Rinse Dry 15-30 minutes 40-55 C Mechanical agitation or Nitrogen bubbling recommended Compatible with IPA rinse No intermediate rinse required QDR suggested 5 10 cycles DI water SRD recommended DI water Consult with EKC s Sales & Engineering staff to establish a process optimized to your specific situation and for any other support needs 2008 EKC Technology / DuPont Electronic Technologies 14
Process Information Bath Life Studies Cu etch rate (A/min) 18 16 14 12 A/min 10 8 6 Bath Life (2 wafers every 6 hrs) Bath Loading ( 170 300mm 120um thick) 2nd - Bath Loading ( 186 300mm 120um thick) 4 2 0 0hr 6hr 12hr 18hr 24hr 30hr 36hr 42hr 48hr 54hr 60hr 66hr 72hr Hours 75 liter tank 300 mm wafers - 120 um film Temp: 60C Blue line = 2 wafers/6hr Pink line = 170 wafers Red Line = 186 wafers 2008 EKC Technology / DuPont Electronic Technologies 15
Process Information DryFilm Resist Loading Capability Loading = 170-300mm wafers, 120mu thick WBR Dry Film in 1 tank 75 liters Chemical: 2~3-month old EKC162 Wet bench tank: Double tank, 75LX2, total around 150L. - Commercial wet bench (Grand Plastic Tech, local Taiwan company). Reach the cleaning limit at the ~42th hour Wafer size Film Thickness um Loading (wafers/75liters) 12 120 170 12 100 204 12 75 272 8 120 383 8 100 458 8 75 612 8 70 654 Customer Data Calculated Data 2008 EKC Technology / DuPont Electronic Technologies 16
Resist/PI Removed by EKC162 Co-designed and Optimized for: DuPont WBR2000 -negative tone acrylic DFR (thick) DuPont MX5000 series (5-50 um, TSV,MEMS, tenting applications etc..) HD-4000 Series PI uncured Competitive Resists tested: JSRTHB151N-Negative tone bumping resist (thick) AZ125NXT -Negative tone bumping resist (thick) AZ4562 positive bumping resist (thin) Morton GA3.0/GA4.0 negative tone acrylic DFR (thick) TOK P50120 negative tone acrylic DFR (thick) Ashai Kasei DFR CXA240 & CX8040-negative tone acrylic DFR (thick) 2008 EKC Technology / DuPont Electronic Technologies 17
Optical Microscope Observation WBR2000 Dry Film Resist Wafer EKC162 /55C/20min Eutectic PbSn Bump EKC162 /55C/20min PbSn Bump 2008 EKC Technology / DuPont Electronic Technologies 18
DuPont WBR 2000 seires 55 C, 20 min PbSn Bump 55 C, 30min Cu Bump DuPont MX 5000 seires 55 C, 1 min 2008 EKC Technology / DuPont Electronic Technologies 19
HD-4000 Series (Post Develop PI on Cured PI) 55 C, 20 min Before Clean After EKC162 Clean Removed Uncured HDMS 4000 PI with no attack to the cured HDMS 4000 PI 2008 EKC Technology / DuPont Electronic Technologies 20
Competitive Resist Data
JSRTHB151N 50 & 70um 35-60 C, 20-40 min PbSn Bump 50 um 35 C 25-40 mins 70um- 45-55 C 20-40 mins 70um, SEZ SWT 60 C 180-330 secs 2008 EKC Technology / DuPont Electronic Technologies 22
AZ 125NXT 100um 65 C, 45 min Cu Bump, Cu Line 100 µm dots, layout 1 : 0.3 75 µm dense lines 80 µm dense lines 90 µm dense 100 µm dense lines lines 100 µm dots, layout 1 : 0.7 75 µm dots, layout 1 : 1 80 µm dots, layout 1 : 1 90 µm dots, layout 1 : 1 100 µm dots, layout 1 : 1 2008 EKC Technology / DuPont Electronic Technologies 23
AZ 4562 50 C, 3 min PbSn Bump 2008 EKC Technology / DuPont Electronic Technologies 24
Morton GA 3.0 55 C, 20 min PbSn Bump 2008 EKC Technology / DuPont Electronic Technologies 25
TOK P50120 100um 50 & 60 C, 25 & 15 min PbSn Bump 50 C 25min 60 C 18min 2008 EKC Technology / DuPont Electronic Technologies 26
Asahi CXA240 55 C, 30 min Pb Bump Asahi CX8040 45 C 60 & 90 min Pb Bump 60 min 90 min 2008 EKC Technology / DuPont Electronic Technologies 27
Results and Summary Removes and dissolves DuPont WBR Dry Film faster than competitive films Compatible with normally cured HD-4000 Series and HD-8800 Series for wafer level & chip scale packaging Completely removes uncured HD-4000 Series PI Completely removes liquid resist Complete, reliable removal of resists, without re-deposit problems Shorter stripping times, at lower temperatures Wide process latitude Full rework capability Long bath life and high wafer capacity, without sludge accumulation in the process tool Compatibility with a wide range of metallurgies Capability to handle both electroplated and photo stencil solder bumping processes Effective, efficient spray tool and wet bench processing 2008 EKC Technology / DuPont Electronic Technologies 28
2008 EKC Technology / DuPont Electronic Technologies 29
Supplement Slides
Safety Health & Environment (SHE) Handling and Storage Keep tightly closed and store in a dry, well ventilated area 40 to 90 F (5 to 32 C) is recommended Keep in original vented containers Keep away from strong oxidizing agents, acids, and ketones Prevent skin and ey contact Avoid inhalation of vapor or mist Personal Protection Respiratory Protection = No personal respiratory equipment required when operated under proper ventilation, such as a wet bench or fume hood. In case of insufficient ventilation, wear suitable respiratory equipment. (see MSDS for details) Wear Nitrile, Neoprene or Latex clothing and gloves, and chemical resistant boots when there is a probability of liquid contact. Wear chemical goggles Avoid contact with skin, eyes and clothing. Remove and wash contaminated clothing and gloves, including the inside, before re-use. Disposal Can be landfilled or incinerated, when in compliance with local regulations. Incineration at a facility with appropriate permits or authorizations is the recommended method of disposal. Spent CSX-W62 should be segregated from ketones and gamma butyrolactone. (See MSDS for more details) Dispose of package in compliance with local regulation (See MSDS for more details) 2008 EKC Technology / DuPont Electronic Technologies 31
Safety Health & Environment (SHE) Hazard Classification/Identification Based on the EU Commissions Directive 2001/59/E, which sets out Annex VI to the Dangerous Substances Directive, 67/548/EEC as amended, classifies substance with a LD50/dermal/rat or rabbit of,50 mg/kg as very toxic by skin contact. The purpose of Annex VI is to provide a harmonized basis for the classification and labeling of dangerous substances and preparations with EU Member State countries. The 'trigger' levels for toxic substances within preparation blends is based on a volume percentage level, in the absence of any credible toxicity data for that preparation blend. In the case of TMAH we have been guided to use a Guinea Pig toxicity study, this classes the substances as Highly Toxic (T+). This change in classification is due to the skin tox data of Eastman Kodak (25 to 50 mg/kg) In the absence of data on the product itself, the conventional method as per Dir 1999/45/EC, the so called preparations directive needs to be applied and it specifies that a preparation containing a Highly Toxic substance (T+) in concentrations between 1-7% be classified as toxic. The contradiction we have is that the classification criteria is on rats or rabbits, whereas our data (Eastman Kodak) was done on guinea pigs. It is known that guinea pigs are often more sensitive than rats or rabbits and consequently the classification in question could be overstated. 2008 EKC Technology / DuPont Electronic Technologies 32