Technical Data Sheet CIRCUPOSIT LC-9100 Electroless Copper For PWB Metallization Applications Regional Product Availability Description Asia-Pacific CIRCUPOSIT LC-9100 Electroless Copper is an integral part of the CIRCUPOSIT PTH Low-build Electroless Copper Process, Dow Electronic Materials unique, patented process that defines a new standard for low-build through-hole plating. This novel self-accelerating electroless copper eliminates the need for a separate accelerator step, saving space, increasing process speed, and improving reliability and quality. CIRCUPOSIT LC-9100 Electroless Copper offers ease of process control operation; low cost and built- in process flexibility available to the marketplace. CIRCUPOSIT LC-9100 Electroless Copper has a wide operating window and offers exceptional stability. In addition, the CIRCUPOSIT LC-9100 Electroless Copper bath is based upon EDTA as the chelate. The bath yields deposits that are smooth, bright pink, uniform in color and low stress. At an operating temperature of 30-36 o C (86-97 o F), the CIRCUPOSIT LC-9100 Electroless Copper will deposit 0.25-0.50 um (10-20 millionths of an inch) in 15 minutes. Advantages Bath Make Up Formulated to eliminate the need for an accelerator Low-stress deposit offers excellent adhesion even on high-performance substrates Enhanced hole-wall adhesion and coverage Strong copper to copper adhesion Exceptional bath stability; reduces required bath maintenance Excellent process latitude Economically and easily waste treated Suitable for both panel or semi-panel plate operations Use vigorous air agitation while adding the components in the order shown: Deionized (D.I.) Water 75% by volume CIRCUPOSIT LC-9100E 2.7% by volume CIRCUPOSIT LC-9100C Electroless Copper 4.3% by volume 1.0% by volume CUPOSIT TM Z Component 3.3% by volume CUPOSIT Y Component 1.6% by volume D. I. Water To final tank volume After mixing and raising the solution to operating temperature, the bath is ready to use. Page 1 of 10
Bath Operation Temperature: 30-36 o C (optimum 33 o C) / 86-97 o F (optimum 91 o F) Deposition 0.25-0.50µm (10-20 millionths of an inch) Thickness and will typically be plated by a cycled bath, Immersion Time*: operating at 33 o C (91 o F), in 15 minutes Bath Loading: 0.50-4.5 dm 2 /L of surface area /0.20-1.80 Agitation: ft 2 /gal. Continuous air agitation is required, including periods when the bath is stored Use rack agitation when operating the bath (12-15 strokes per minute / 30-50 mm per stroke) Filtration: Constant filtration through a 1-10 µm polypropylene cartridge filter Bath turnover should be a minimum of three times per hour Tank Design: Rinsing: An overflow-type tank with a discrete sump is recommended Counterflow rinses as required *These properties are typical, but do not constitute specifications. Automatic Controller Yield Copper Control by UV Spectrophotometry (730 nm) The SE-471 Single Channel Controller has been developed by Dow Electronic Materials to precisely and automatically control electroless copper baths such as CIRCUPOSIT LC- 9100 Electroless Copper; and its use is recommended. When operated properly, one liter of CIRCUPOSIT LC-9100A Electroless Copper can be used to process 30 m 2 laminate/liter (325 ft 2 /liter). The yield of the other bath components will vary according to their replenishment ratios. Copper is determined spectrophotometrically by measurement of the absorbance at 730nm. Reagents and Equipment a) Buffer Solution: Add 100 grams of sodium acetate, anhydrous (or 166 grams of sodium acetate trihydrate) to 600 ml of distilled water, stir to dissolve; add 25mL of acetic acid, mix well and dilute to one liter WARNING! Proper care must be taken to avoid physical contact with acetic acid solution as severe burns can result. The use of proper safety equipment is necessary, including chemical goggles, chemical gloves, and suitable protective clothing. b) UV Spectrophotometer capable of 730 nm I a) Prepare a fresh CIRCUPOSIT LC-9100 Electroless Copper bath as follows: One Liter Make-up (Use a 1 liter volumetric flask) D.I. Water 500 ml CIRCUPOSIT LC-9100E Electroless Copper 27 ml Page 2 of 10
Copper Control by UV Spectrophotome try (730 nm) (Con t.) CIRCUPOSIT LC-9100C Electroless Copper CIRCUPOSIT LC-9100A Electroless Copper CUPOSIT Z Component Bring volume up to 1 liter with D.I. water. 43 ml 10 ml 33 ml b) Prepare a 100% standard solution by making the following dilution of the above fresh bath: CIRCUPOSIT LC-9100 Fresh Bath 20 ml Buffer Solution 40 ml This standard should have a one-month shelf life. c) Ensure the spectrophotometer is warmed up for at least 15 minutes and wave length is set to 730nm. d) Insert blank solution in the first sample well (Buffer Solution) and zero. e) Fill a cuvette with 100% standard solution and insert into second sample well and record the absorbance reading as STD A. Note: The absorbance reading from the copper standard is good for one week. Each week the absorbance on the copper standard should be checked and the calculation adjusted if necessary. f) Accurately pipette 10.0 ml of sodium acetate buffer solution into a clean beaker. Accurately pipette 5.0 ml of CIRCUPOSIT LC-9100 Copper Bath into same beaker. Mix well and fill cuvette. g) Insert cuvette of bath sample into the second sample well. Record the absorbance reading as BATH. Calculation Abs of BATH Abs of STD A or Abs of BATH Abs of STD A x 100 = Percent copper x 2.0 = g/l copper Copper Control by Wet Analysis Copper is determined iodometrically using sodium thiosulfate as a titrant and starch as an indicator. Reagents a) 20% sulfuric acid: Under a hood, carefully add 200 ml of concentrated sulfuric acid to 600 ml of distilled water; allow to cool and dilute to one liter b) Potassium iodide, reagent grade b) 0.10N Sodium thiosulfate, standardized c) 10% Potassium Thiocyanate (KSCN): Dissolve 100g potassium thiocyanate in distilled water and dilute to one liter d) Starch indicator (1%) e) Sulfamic acid, reagent grade WARNING! Proper care must be taken to avoid physical contact with sulfuric acid solution as severe burns can result. The use of proper safety equipment is necessary, including chemical goggles, chemical gloves, and suitable protective clothing. Page 3 of 10 WARNING! Proper care must be taken to avoid physical contact with sulfamic acid solution as severe burns can result. The use of proper safety equipment is necessary, including chemical goggles, chemical gloves, and suitable protective clothing.
Copper Control by Wet Analysis (Con t.) I a) Pipette a 20.0 ml aliquot of CIRCUPOSIT LC-9100 Electroless Copper bath into a 250 ml Erlenmeyer flask. b) Under a hood, with gentle stirring, add 40 ml of 20% sulfuric acid and 0.50 grams of sulfamic acid. c) Bring solution to a boil for approximately one minute and remove from heat. d) Allow to cool for five minutes. e) Add 2 grams potassium iodide and stir for three minutes to ensure completed dissolution. f) Titrate with 0.10N sodium thiosulfate, using a 10 ml burette, to the straw color. g) Add 20 ml of 10% KSCN and 5 ml of 1% starch indicator. h) Continue titrating to the off-white end point. Calculation Copper content (g/l) = ml titrant x Normality of sodium thiosulfate (N) x 63.54 Sample size (20 ml) Sodium Hydroxide and Formaldehyde The sodium hydroxide is determined potentiometrically by an acid base titration to ph 10.2. The formaldehyde is determined by the titration of the sodium hydroxide formed during the addition reaction between formaldehyde and sodium sulfate. Reagents a) Hydrochloric acid, 0.10N standardized b) Sodium hydroxide, 0.10N standardized c) Sodium sulfite, approximately 1M (126 g/l) and buffered to a ph of 10.0 WARNING! Proper care must be taken to avoid physical contact with hydrochloric acid solution as severe burns can result. The use of proper safety equipment is necessary, including chemical goggles, chemical gloves, and suitable protective clothing. I a) Pipette a 5 ml sample of the bath into a 250 ml beaker. b) Add approximately 100 ml of distilled water. c) Using a ph meter buffered at 10.0, titrate to a ph of 10.2 with 0.10N HCl. Record ml titrated for the caustic calculation. d) Adjust the ph to 10.0 with the 0.10N HCl. e) Add 25 ml of 1M sodium sulfite solution. f) Titrate to a ph of 10.0 with 0.10N HCl. Record the mls of HCl used in this step for the formaldehyde calculation. Calculations g/l Total alkalinity (as NaOH) = ml HCl x N x 8 g/l Free formaldehyde = ml HCl x N x 6 EDTA Control Total EDTA is determined as the sum of complexed and free EDTA. Complexed EDTA is determined for the copper concentration. Free EDTA is determined by titration with a standardized copper solution. Page 4 of 10
EDTA Control (Con t.) I Reagents a) ph 10.0 ammonium chloride buffer: Dissolve 70 grams of ammonium chloride in approximately 400 ml distilled water; add ammonium hydroxide to a ph of 10.0; dilute to 1 liter with distilled water b) 0.016M Cu 2+ Standard: Dissolve 4.000 grams of CuSO 4 5 H 2O in distilled water and dilute to 1 liter; standardize with primary EDTA titrant c) 0.1% PAN indicator: Dissolve 0.1 gram of 1-(2-pyridylazo)-2-naphthol in ethanol and dilute to 100 ml a) Pipette a 10.0 ml aliquot of CIRCUPOSIT LC-9100 Electroless Copper bath into a 250 ml Erlenmeyer flask and add approximately 75 ml of distilled water. b) Add 20 ml of ph 10.0 buffer and 10-12 drops of 0.1% PAN indicator. c) Titrate with 0.016 M Cu 2+ Standard to violet end point. Calculation Complexed EDTA g/l= 6.55 x Copper Content (g/l) Free EDTA g/l= ml Cu 2+ x Molarity (0.016) x 416 aliquot (10 ml) Total EDTA* g/l= Complexed EDTA + Free EDTA *Note: as EDTA 4Na 2H 2O SR Control SR is determined spectrophotometrically by measurement of the absorbance at 282nm. I Reagents a) CUPOSIT TM 1120SR Concentrate b) Ethyl Acetate a) Prepare a fresh CIRCUPOSIT LC-9100 Electroless Copper bath as follows: One Liter Make-up (Use a 1 liter volumetric flask): D.I. Water 500 ml CIRCUPOSIT LC-9100E Electroless Copper 27 ml CIRCUPOSIT LC-9100C Electroless Copper 43 ml CIRCUPOSIT LC-9100A Electroless Copper 10 ml CUPOSIT Z Component 33 ml Bring volume up to 1 liter with D.I. water. Page 5 of 10
SR Control (Con t.) a) Pipette 20.0ml of electroless copper working bath into a 100ml separation funnel. b) Pipette 20.0ml of ethyl acetate into the funnel. c) Stopper the funnel tightly, shake vigorous for 1 min and then release pressure and shake for another 1 min. Afterward the funnel should be allowed to stand for 5 minutes to allow phase separation. d) Zero the UV-VIS with ethyl acetate at 282nm. e) Measure and record the absorbance at 282nm for the sample (Abs1). f) Repeat step a) to step e) for standard bath (Abs 2). V. Calculations SR (ppm) = (Abs 1/ Abs 2) x 8 Bath Control and Replenishment Maintain bath volume with distilled or deionized water. The CIRCUPOSIT LC-9100 Electroless Copper bath is designed to be controlled, during continuous operation, based on the copper concentration. Using one of the supplied analytical procedures, periodically analyze the bath for copper concentration and replenish according to the following schedule. Replenishment Schedule for 100 Liter Bath Copper Content (g/l) 2.3 2.1 Bailout (liter CIRCUPOSIT LC-9100A (liters) CIRCUPOSIT LC-9100E (liters) CUPOSIT TM Y (liters) 1.9 0.60 0.10 0.10 0.20 0.20 1.7 1.20 0.20 0.20 0.40 0.40 1.5 1.80 0.30 0.30 0.60 0.60 1.3 2.40 0.40 0.40 0.80 0.80 If automatic replenishment is used, set pumps to the following ratios. 6.00 1.00 1.00 2.00 2.00 CUPOSIT Z (liters) Automatic Dosing Based on Throughput Initial Guidelines CIRCUPOSIT LC-9100 Electroless Copper bath operating at 33 o C with a 15 minute plating time: CIRCUPOSIT LC-9100A Electroless Copper 33.3 ml/m 2 laminate (3.11 ml/ft 2 ) CIRCUPOSIT LC-9100E Electroless Copper 33.3 ml/m 2 laminate (3.11 ml/ft 2 ) Important! It is essential that vigorous agitation (air or mechanical) be employed when making replenishments (especially of the CIRCUPOSIT LC-9100A Electroless Copper). Additions of the CIRCUPOSIT LC-9100A Electroless Copper should be made so that the solution to which the CIRCUPOSIT LC-9100A Electroless Copper is added passes through the filter before entering the main bath. Page 6 of 10
Automatic Dosing Based on Throughput (Con t.) To facilitate optimum bath performance, it is important to bail out the suggested volume of bath when making replenishments. This will automatically maintain the EDTA concentration within the optimum ranges. To facilitate consistently exceptional results, maintain the bath within the following ranges: Bath Operation Component Range Recommended Copper 1.7-2.3 g/l 2.0 g/l EDTA 24.0-40.0 g/l 32.0 g/l Sodium Hydroxide 9.5-11.5 g/l 10.5 g/l Formaldehyde 2.5-4.5 g/l 3.5 g/l Specific Gravity 1.04-1.13 1.08-1.12 SR 5-10 ppm 8 ppm During idle times, or after lengthy shutdowns, the formaldehyde and sodium hydroxide concentrations will need to be independently adjusted. Please use above replenishment schedule as standard. Schedule will change due to different operating conditions. Please analyze the bath before you use, and during operations, make replenishment schedule according to your own operation conditions. It is necessary to adjust each component of the CIRCUPOSIT LC-9100 Electroless Copper prior to starting operation after extended storage (more than 8 hours). When one liter of each concentrated solution is added to a 100 liter bath, the content of Cu, EDTA, NaOH, and HCHO will increase as follows: Bath Operation Product Content grams/liter CIRCUPOSIT LC-9100A Electroless Copper Copper 2.00 CIRCUPOSIT LC-9100E Electroless Copper EDTA.4Na.2H2 O 4.40 CUPOSIT TM Z Component Sodium Hydroxide 3.45 CUPOSIT Y Component Formaldehyde 2.50 If the bath is diluted during weekly bath maintenance, it will be necessary to adjust the copper content using CIRCUPOSIT LC-9100A Electroless Copper When one liter of CIRCUPOSIT LC-9100A Electroless Copper is added to a 100 liter bath, the copper content will increase by 2.0 grams/liter. Bath Storage The bath should be stored at 80-100% copper at 18-25 o C (64-77 o F). Air agitation is recommended during storage. Before starting up a CIRCUPOSIT LC-9100 Electroless Copper bath, the copper, sodium hydroxide and formaldehyde concentrations should be brought to optimum operating levels. Page 7 of 10
Product Data CIRCUPOSIT LC-9100A Electroless Copper Appearance: Green Specific Gravity: ~1.35 ph: < 2.0 CIRCUPOSIT LC-9100E Electroless Copper Appearance: Water-white to pale yellow Specific Gravity: ~1.20 ph: ~10.0 CIRCUPOSIT LC-9100C Electroless Copper Appearance: Water-white to pale yellow Specific Gravity: ~1.20 ph: ~10.0 Equipment Tanks: Polypropylene, polyethylene or PVC Racks: 304 or 316 stainless steel, or Teflon coated. (316 stainless steel is preferred) Heaters: Teflon or Teflon coated Filter Media: Polyproylene cartridge (1-10 microns) or a 50 micron felt bag Air Lines: Rigid CPVC Page 8 of 10
Handling Precautions Before using this product, or the analytical reagents required for its control, consult the Material Safety Data Sheet (MSDS)/Safety Data Sheet (SDS) for details on material hazards, recommended handling precautions and product storage. CAUTION! Keep combustible and/or flammable products and their vapors away from heat, sparks, flames and other sources of ignition including static discharge. Processing or operating at temperatures near or above product flashpoint may pose a fire hazard. Use appropriate grounding and bonding techniques to manage static discharge hazards. CAUTION! Failure to maintain proper volume level when using immersion heaters can expose tank and solution to excessive heat resulting in a possible combustion hazard, particularly when plastic tanks are used. Storage Disposal Considerations Store products in tightly closed original containers at temperatures recommended on the product label. Dispose in accordance with all local, state (provincial) and federal regulations. Empty containers may contain hazardous residues. This material and its container must be disposed in a safe and legal manner. It is the user's responsibility to verify that treatment and disposal procedures comply with local, state (provincial) and federal regulations. Contact your Dow Electronic Materials Technical Representative for more information. Product Stewardship Customer Notice Dow has a fundamental concern for all who make, distribute, and use its products, and for the environment in which we live. This concern is the basis for our product stewardship philosophy by which we assess the safety, health, and environmental information on our products and then take appropriate steps to protect employee and public health and our environment. The success of our product stewardship program rests with each and every individual involved with Dow products - from the initial concept and research, to manufacture, use, sale, disposal, and recycle of each product. Dow strongly encourages its customers to review both their manufacturing processes and their applications of Dow products from the standpoint of human health and environmental quality to ensure that Dow products are not used in ways for which they are not intended or tested. Dow personnel are available to answer your questions and to provide reasonable technical support. Dow product literature, including safety data sheets, should be consulted prior to use of Dow products. Current safety data sheets are available from Dow. For Industrial Use Only. This information is based on our experience and is, to the best of our knowledge, true and accurate. However, since conditions for use and handling of products are beyond our control, we make no guarantee or warranty, expressed or implied, regarding the information, the use, handling, storage or possession of the products, or the applications of any process described herein or the results sought to be obtained. Nothing herein shall be construed as a recommendation to use any product in violation of any patent rights. Contact: North America: 1-800-832-6200 Japan: (+81) 3-5460-4696 Asia: (+852) 2680-6888 Europe: (+41) 41-259-44-44 http://www.dow.com NOTICE: No freedom from infringement of any patent owned by Dow or others is to be inferred. Because use conditions and applicable laws may differ from one location to another and may change with time, Customer is responsible for determining whether products and the information in this document are appropriate for Customer's use and for ensuring that Customer's workplace and disposal practices are in compliance with applicable laws and other government enactments. The product shown in this literature may not be available for sale and/or available in all geographies where Dow is represented. The claims made may not have been approved for use in all countries. Dow assumes no obligation or liability for the information in this document. References to Dow or the Company mean the Dow legal entity selling the products to Customer unless otherwise expressly noted. NO WARRANTIES ARE GIVEN; ALL IMPLIED WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE ARE EXPRESSLY EXCLUDED. Page 9 of 10