Adhesion Technology of Copper Surface for High Frequency PWBs - - PowerPoint PPT Presentation

Adhesion Technology of Copper Surface for High Frequency PWBs - FlatBOND GT Process - MEC Company Ltd. R&D Unit, Team 2 Approved Confirmed Prepared M. Kawaguchi T.Goda MEC COMPANY LTD. MEC COMPANY LTD. MEC COMPANY LTD. MEC COMPANY LTD. Prep: 2015.04.30 1 Confidential

Content of Presentation Content of Presentation 1. Background of the Development 2. FlatBOND GT Process Flow 3. Characterizations of FlatBOND GT Surface 4. Adhesion of FlatBOND GT Process to Prepregs 5. Comparison in Transmission Loss MEC COMPANY LTD. MEC COMPANY LTD. MEC COMPANY LTD. MEC COMPANY LTD. Prep: 2015.04.30 2 Confidential

1. Background of the 1. Background of the Development Development MEC COMPANY LTD. MEC COMPANY LTD. MEC COMPANY LTD. MEC COMPANY LTD. Prep: 2015.04.30 3 Confidential

ETCHBOND CZ Roadmap ETCHBOND CZ Roadmap Finer L/S Frequency of Higher Signal Surface Surface Roughening Roughening CZ-8100 CZ-8101 Roughly Roughen Finely Roughen Less Etching High Adhesion MEC COMPANY LTD. MEC COMPANY LTD. MEC COMPANY LTD. MEC COMPANY LTD. Prep: 2015.04.30 4 Confidential

Surface Roughness and Line Shape Surface Roughness and Line Shape L/S=30/30 µ m(1.18/1.18mil) ETCHBOND CZ-8100 2µm(80 µ in) etching ETCHBOND CZ-8101 1µm(40 µ in) etching MEC COMPANY LTD. MEC COMPANY LTD. MEC COMPANY LTD. MEC COMPANY LTD. Prep: 2015.04.30 5 Confidential

Possible Problem in the Near Future Possible Problem in the Near Future Chemical Roughening Transmission Loss of Signal Reduction in Line Width (Skin Effect) for Finer Pattern Adhesion w/o Etching Flat Copper Surface Flat BOND MEC COMPANY LTD. MEC COMPANY LTD. MEC COMPANY LTD. MEC COMPANY LTD. Prep: 2015.04.30 6 Confidential

Surface Treatment Technology Roadmap Surface Treatment Technology Roadmap Finer L/S Frequency of Higher Signal Surface Surface Roughening Roughening Flat BOND CZ-8100 CZ-8101 Flat Roughly Roughen Finely Roughen Less Etching w/o Etching High Adhesion Flat High Adhesion MEC COMPANY LTD. MEC COMPANY LTD. MEC COMPANY LTD. MEC COMPANY LTD. Prep: 2015.04.30 7 Confidential

2. FlatBOND GT Process Flow 2. FlatBOND GT Process Flow MEC COMPANY LTD. MEC COMPANY LTD. MEC COMPANY LTD. MEC COMPANY LTD. Prep: 2015.04.30 8 Confidential

FlatBOND GT Process FlatBOND GT Process Alkaline Cleaning MECBRITE CA-5372 Water Rinse Copper Diluted H 2 SO 4 Acid Cleaning Water Rinse Form Metal Layer FlatBOND GT Cu/Sn/Ni Alloy Layer Copper FlatBOND GW Post Cleaning Water Rinse FlatBOND GC Form Anti-tarnish Layer Dry Anti-tarnish Layer Copper Water Rinse Dry MEC COMPANY LTD. MEC COMPANY LTD. MEC COMPANY LTD. MEC COMPANY LTD. Prep: 2015.04.30 9 Confidential

Standard Process Conditions Standard Process Conditions Process Condition No. Step Shaft Material Solution Temp. Time Alkaline 1 SUS CA-5372 35 ℃ ℃ (95F) 15sec(Spray) Cleaning ℃ ℃ 15sec x 3times 2 Rinse-1 SUS DI water R.T. (Spray) 15sec(Spray) 3 Acid Cleaning Carbon Diluted H 2 SO 4 30 ℃ ℃ (86F) /30sec(dip) ℃ ℃ 15sec x 3times 4 Rinse-2 SUS DI water R.T. (Spray) 5 FlatBOND GT Titanium FlatBOND GT 30 ℃ ℃ (86F) 30sec(dip) ℃ ℃ 6 FlatBOND GW Titanium FlatBOND GW 30 ℃ ℃ (86F) 10sec(dip) ℃ ℃ 15sec x 3times 7 Rinse-3 SUS DI water R.T. (Dip ＆ ＆ Spray) ＆ ＆ 8 FlatBOND GC SUS FlatBOND GC 30 ℃ ℃ (86F) 30sec(dip) ℃ ℃ 9 Dry-1 SUS - 90 ℃ ℃ (194F) 30sec ℃ ℃ 15sec x 3times 10 Rinse-4 SUS DI water R.T. (Spray) 11 Dry-2 SUS - 80 ℃ ℃ (176F) 30sec ℃ ℃ MEC COMPANY LTD. MEC COMPANY LTD. MEC COMPANY LTD. MEC COMPANY LTD. Prep: 2015.04.30 10 Confidential

3. Characterizations of the 3. Characterizations of the FlatBOND GT Surface FlatBOND GT Surface MEC COMPANY LTD. MEC COMPANY LTD. MEC COMPANY LTD. MEC COMPANY LTD. Prep: 2015.04.30 11 Confidential

Surface Composition by XPS Surface Composition by XPS Thickness of FlatBOND GT layer: 0.05 - 0.1µm(2 - 3.9µin) Surface Composition of FlatBOND GT FlatBOND Surface 100 90 80 70 ) C % 60 ( O % 50 c Copper i 40 m Nickel 30 o t Tin 20 A 10 0 0 20 40 60 80 100 120 140 160 180 200 Sputtering time(sec) 0.362 Å Å /sec(SiO 2 ) Å Å MEC COMPANY LTD. MEC COMPANY LTD. MEC COMPANY LTD. MEC COMPANY LTD. Prep: 2015.04.30 12 Confidential

Assumed Mechanism of FlatBOND GC Assumed Mechanism of FlatBOND GC R 2 Effective element of R 2 FlatBOND GC chemical H 2 O =Silane coupling agent + 3R 1 OH R 1 O - Si - OR 1 HO - Si - OH (Formation of silanol groups OR 1 OH by hydrolysis) R 2 R 2 R 2 R 2 HO - Si -OH HO - Si -OH HO - Si -OH HO - Si -OH H H H H O O O O O O O O FlatBOND GT FlatBOND GT Before FlatBOND GC Treatment After FlatBOND GC Treatment There are many -OH groups on the FlatBOND GT treated surface that form covalent bond with Si-OH groups of FlatBOND GC . MEC COMPANY LTD. MEC COMPANY LTD. MEC COMPANY LTD. MEC COMPANY LTD. Prep: 2015.04.30 13 Confidential

Assumed Mechanism of FlatBOND GT Process Assumed Mechanism of FlatBOND GT Process FlatBOND GC R 3 R 3 R 3 R 3 R 2 R 2 R 2 R 2 Resin HO - Si -OH HO - Si -OH HO - Si -OH HO - Si -OH O O O O Cu FlatBOND GT FlatBOND GT (Cu-Sn-Ni) Cu Chemical Functional groups, R 2 , react with functional groups in resin, R 3 , which forms covalent bond. Bonding! MEC COMPANY LTD. MEC COMPANY LTD. MEC COMPANY LTD. MEC COMPANY LTD. Prep: 2015.04.30 14 Confidential

Surface Topography Surface Topography Plated Copper CZ-8101: 1µm FlatBOND GT w/o Treatment (40µin) SEM x3,500 Unlike roughened surface topography with roughening chemical, flat surface is observed after FlatBOND GT treatment. MEC COMPANY LTD. MEC COMPANY LTD. MEC COMPANY LTD. MEC COMPANY LTD. Prep: 2015.04.30 15 Confidential

Detailed Analysis by FE Detailed Analysis by FE- -SEM SEM SEM FE-SEM (x3,500) (x100,000) Plated Copper w/o Treatment <0.1µm(4µin) FlatBOND GT Minute holes in nano-scale are observed. Mechanical Bonding? MEC COMPANY LTD. MEC COMPANY LTD. MEC COMPANY LTD. MEC COMPANY LTD. Prep: 2015.04.30 16 Confidential

Pattern Shape Pattern Shape Pattern Width: 50µm(1.97mil) Before treatment After FlatBOND GT Process No change in pattern shape is observed after treatment. MEC COMPANY LTD. MEC COMPANY LTD. MEC COMPANY LTD. MEC COMPANY LTD. Prep: 2015.04.30 17 Confidential

4. Adhesion of FlatBOND GT 4. Adhesion of FlatBOND GT Process to Prepregs Process to Prepregs MEC COMPANY LTD. MEC COMPANY LTD. MEC COMPANY LTD. MEC COMPANY LTD. Prep: 2015.04.30 18 Confidential

Evaluation Method Evaluation Method � Resin Type: MEGTRON6(Panasonic, Dk=3.5, Df=0.002@1GHz) MEGTRON7(Panasonic, Dk=3.3, Df=0.001@1GHz) LW-900G(Hitachi Chemical, Dk=3.6, Df=0.003@1GHz) � Copper Foil: 35 µ m(1oz) Standard Cu Foil (3EC- Ⅲ ) � Surface Treatment: a) CZ-8101: 1µm(40µin) etching b) BO-7790V: 1.5 µ m(60µin) etching c) FlatBOND GT Process � Evaluation Items: Peel strength measurement 1) Initial 2) After reflow* *Reflow condition is for Pb-free solder . MEC COMPANY LTD. MEC COMPANY LTD. MEC COMPANY LTD. MEC COMPANY LTD. Prep: 2015.04.30 19 Confidential

Evaluation Method Evaluation Method Peel Strength Measurement M side Treated Copper S side (Treated Side) Foil Prepreg Laminate Carrier Board @ MEC Cut 1cm(0.39in) in width As is Measure Peel Strength JIS C 6481 Test Coupon Reflow MEC COMPANY LTD. MEC COMPANY LTD. MEC COMPANY LTD. MEC COMPANY LTD. Prep: 2015.04.30 20 Confidential

Peel Strength Peel Strength Peel strength of FlatBOND GT Process is higher than that of roughening treatments for all materials evaluated. MEC COMPANY LTD. MEC COMPANY LTD. MEC COMPANY LTD. MEC COMPANY LTD. Prep: 2015.04.30 21 Confidential

Peel Strength before & after Reflow Peel Strength before & after Reflow MEGTRON6 The peel strength of FlatBOND GT Process is high and stable even after 10 times reflow. MEC COMPANY LTD. MEC COMPANY LTD. MEC COMPANY LTD. MEC COMPANY LTD. Prep: 2015.04.30 22 Confidential

5. Comparison in 5. Comparison in Transmission Loss Transmission Loss MEC COMPANY LTD. MEC COMPANY LTD. MEC COMPANY LTD. MEC COMPANY LTD. Prep: 2015.04.30 23 Confidential

Evaluation Method Evaluation Method Inner Treatment � Test Coupon Copper Type: H-VLP(35 µ m(1oz)) 0.28mm 35 µ m M side (11mil) (1oz) Cu Inner Treatment: a) No treatment b) FlatBOND GT Process c) Black Oxide d) BO-7790V: 1.5 µ m(60µin) etching e) BO-7790V: 2.5 µ m(100µin) etching CCL Thickness ： 0.13mm(5.1mil) Resin Type: MEGTRON6, 0.06mm(2.4mil) x 2 Pattern Length: 100mm(3.9in), 200mm(7.9in) Impedance ： 50 Ω � Evaluation Item S21 measurement by VNA(Agilent technology PNA-X) 10MHz - 50GHz MEC COMPANY LTD. MEC COMPANY LTD. MEC COMPANY LTD. MEC COMPANY LTD. Prep: 2015.04.30 24 Confidential

Comparison in Surface Topography Comparison in Surface Topography b) FlatBOND GT Process a) No treatment c) Black Oxide No photo d) BO-7790V@1.5 µ m(60 µ in) e) BO-7790V@2.5 µ m(100 µ in) a), b): SEM x5,000 d), e): SEM x3,500 MEC COMPANY LTD. MEC COMPANY LTD. MEC COMPANY LTD. MEC COMPANY LTD. Prep: 2015.04.30 25 Confidential