DELTA PASTE FLUX NO CLEAN PF600

Transcription

1 ASIA PACIFIC EDITION DELTA PASTE FLUX NO CLEAN PF600 QUALITEK SINGAPORE PTE LTD. AN ISO 9002 CERTIFIED COMPANY 6, Tuas South Street 5, Singapore TEL: (65) FAX: (65) HOME PAGE: Head Office: 315 Fairbank St., Addison, IL U.S.A. Worldwide Branches: Philippines - China - United Kingdom Mexico The information contained herein is based on data considered accurate and is offered solely for information, consideration, and investigation. Qualitek extends no warranties, makes no representations, and assumes no responsibility as to the accuracy, completeness, or suitability of this data for any purchaser s use. The data on this report relates only to this product and does not relate to use with other material or in the process.

2 Contents 1.0 Introduction 2.0 Paste Flux Qualification 2.1 Spread Test 2.2 Copper Mirror (Flux Induced Corrosion) 2.3 Silver Chromate 2.4 Flouride Spot 2.5 Corrosion 2.6 Surface Insulation Resistance (SIR) 3.0 Packaging and Shipping 4.0 Shelf and Storage 5.0 Material Safety and Data Sheet

3 1.0 Introduction T he following report presents general results and data of Qualitek Paste Flux per Joint Industry Standard J-Std-004 and QQ-S-571E. PF600 paste flux are mixtures of high grade synthetic resin, rosins and thixotropic thickeners. Specially formulated for touch-up soldering, BGA packages and flip chip applications. Paste flux may be applied by screen or stencil printing, pin-transfer and syringe dispensing. It has good wetting and dispensing of all types. Residues after soldering are non-corrosive, nonconductive and highly insulated. It may be left without cleaning. 2.0 Paste Flux Qualification Qualitek paste flux type PF600 has been classified as REMO type flux as per J-STD-004. Paste Flux is a combination of tackifier and fluxing agent specially formualted for touch-up soldering, BGA packages and flip chip applications. Following are the Qualification Test Report and tests conducted on paste flux are per J-STD-004, QQ-S-571E and Qualitek procedure.

4 QUALIFICATION TEST REPORT Flux Type: PF600 FLUX CLASSIFICATION: REMO DATE ORIGINAL QUALIFICATION TESTS COMPLETED: 24/11/2000 File: N91APF600rev0.doc Revision Date: - TESTED BY: TECK AUN Pass: X Fail: Certification Test Requirement Paragraph IPC-TM-650 Method Test Requirement Result Pass/Fail/NA Refer Chp. Spread Test QQ-S-571E % 2.1 Copper Mirror <50% Breakthrough Pass 2.2 Halides Qualitative Silver No Discoloration Pass 2.3 Chromate Fluoride Spot No Colour Change Pass 2.4 Corrosion Minor Corrosion Pass 2.5 Acceptable SIR (uncleaned) hr >1.00E E hrs >1.00E E hrs >1.00E E hrs >1.00E E+11 Control 0 hr >1.00E E hrs >1.00E E hrs >1.00E E hrs >1.00E E+11

5 2.1 Spread Test This test method is based on QQ-S-571E, procedure The spread percentage will give an indication of the paste activity. Five copper coupons bent at the opposite ends to flatten them, with dimensions 0.25 X 50 X 50 mm, is treated with Qualitek s Copper Cleaner to remove oxide layer, rinsed with deionized water and dried. Then the copper coupons are subjected to oxidation in an electric oven at 150 ± 5 C for 1 hour. About 0.5 grams of solder paste is weighed on each test coupon and the coupon is then placed on top of a hotplate maintained at 45 ± 5 C above the liquidus temperature of the solder. The solder is allowed to melt for about 30 seconds after reaching the said temperature. After removing from hotplate, the coupon is placed horizontally and the solder is allowed to solidify. The residue is removed with IPA before the height of the solder spread, H, is measured to the nearest cm with a vernier calliper. An amount of solder paste equal to the total weight of solder paste on the five coupons is melted in a small beaker on the hotplate. The cleaned solder slab is first weighed to the nearest grams in air and then the loss of weight in water is determined to the nearest grams. The loss in weight of the solder slab is divided by five to give the volume, V, of the solder to the nearest cc. The diameter, D, of the equivalent sphere is: D =1.2407(V) 1/3 The spread factor (%) = D - H x 100 D

6 2.2 Copper Mirror (Flux Induced Corrosion) The copper mirror test is conducted per IPC-TM-650 Number The purpose of this test is to determine the corrosiveness of the flux. Discoloration of the copper film due to a superficial reaction or only a partial reduction of the copper film thickness is not considered a failure. A clean copper mirror test panel is placed on a flat surface, mirror up and protected from dust and dirt. The paste flux is applied directly onto the copper mirror without scratching the copper mirror, with a volume approximating a 0.5 mm thickness and 8 mm diameter. One drop of control standard flux is also placed immediately adjacent to the test flux. The test panels are placed in a horizontal position in a dust free desiccator at 23 ± 2 C and 50 ± 5 % RH for 24 ± ½ hours. At the end of the 24 hour period, the test panels are removed. The solder paste and control flux are removed by immersion in clean IPA. The test panels are carefully examined for possible removal or discoloration. The requirements are as follows: Category L M H Condition No Breakthrough Less Than 50% Breakthrough Greater Than 50% Breakthrough 2.3 Silver Chromate This test method is designed to determine the presence of chloride and bromide in soldering flux by visual examination per IPC-TM-650 Number A glass microscope slide is washed with IPA and air dried. A piece of moist silver chromate reagent paper is placed on the glass slide. Excess water is then removed with blotting paper. A thin layer of paste flux is applied directly to the moist reagent paper. After 1 minute of contact time, the paste flux is removed with IPA without disturbing the paper. Each reagent paper is carefully examined for possible colour change to off-white or yellowwhite, in which case indicates presence of chlorides or bromides. Amines, cyanides, isocyanates and others chemicals may cause test failures. Acidic solution, ph less than 3, may react with the reagent paper to result a colour change similar to that obtained with chlorides or bromides.

7 2.4 Fluoride Spot The test method is per IPC-TM-650 Number It is designed to determine the presence of fluoride in soldering flux by visual examination after placement of a drop of test flux in a zirconium alizarin purple lake. About 25 grams of solder paste is used to prepare 25% by weight solution of reflowed solder paste flux. Three spots of fresh zirconium alizarin purple lakes are prepared by adding 1 drop each of zirconium nitrate and sodium alizarin sulphate solutions. One drop of the test flux is added into each of the spot. A clean glass rod is used to mix each spot and any change of colour is noted. A colour change of the lake from purple to yellow is an indication of the presence of fluoride. 2.5 Corrosion The copper coupon corrosion test is conducted per IPC-TM-650 Number to determine the corrosive properties of flux residues under extreme environmental conditions. Any initial colour change that may develop when the test panel is heated during soldering is disregarded. Test panels of copper coupons, each of dimension 0.50 X 51 X 51mm, are circularly depressed about 3.2mm deep in the centre. One corner of each test panel is bent to facilitate subsequent handling with tongs. Test panels are freshly pretreated. The panels are degreased with acetone and then immersed in 5% sulphuric acid (by volume) at 65 ± 5 C for 1 minute to remove tarnish film. Then they are immersed in a solution of 25% m/v ammonium persulphate (0.5% v/v sulphuric acid) at 23 ± 2 C for 1 minute to etch the surface uniformly. The panels are washed in running tap water for a maximum of 5 seconds followed by immersion in 5% sulphuric acid (by volume) at 23 ± 2 C for 1 minute. They are then washed for 5 seconds in running tap water and rinsed thoroughly in deionized water. After rinsing with acetone, they are allowed to air dry. About 1.00 ± 0.05 gram of solder paste is weighed and placed in the centre depression of each test panel. Each test panel is lowered into the surface of molten solder heated at about 235 ± 5 C and maintained for about 5 ± 1 seconds. Test panels are examined carefully at 20X for subsequent comparison after humidity exposure. Test panels are then preheated to 40 ± 1 C for 30 ± 2 minutes before being suspended in a humidity chamber controlled at 40 ± 1 C and 93 ± 2% RH for 240 hours. Test panels are removed after 10 days and examined under 20X for corrosion, described as follows: a) Excrescences at the interfaces of the flux residue and copper boundary, or the residues or discontinuities in the residues b) Discrete white or colored spots in the residues

8 2.6 Surface Insulation Resistance (SIR) SIR test, per IPC-TM-650 Number , is to characterise fluxes by determining the degradation of electrical insulation resistance of printed circuit board specimens after exposure to the specified flux at high humidity and heat conditions. Test boards used are IPC-B-24 test pattern, which consists of four comb patterns per board. Each comb has 16 mils lines and 20 mils spacing. Test coupon is cleaned by scrubbing with soft bristle brush in clean deionized water for a minimum of 30 seconds. It is then rinsed thoroughly first with deionized water and finally with IPA. Three boards are reflowed pattern side up for each type of solder paste. Any board with bridging is discarded. Teflon insulated wires are soldered onto the connection points with water white rosin flux. In addition two cleaned bare boards are used as control during the SIR test. Boards are placed in a vertical position in the chamber such that the air flow is parallel to the direction of boards. Oven is first stabilised at 85 ± 2 C and humidity at 20% for 3 hours. The humidity is then ramped to 85 ± 2% over a minimum 15 minute period. Oven is further allowed to equilibrate for at least 1 hour before a DC bias voltage of V is applied to all the specimens. Measurements are taken at 0, 24, 96 and 168 hours under a test voltage of 100 V DC (after reverse polarity for one minute). Boards are examined under 10X to 30X within 24 hours of completing the test for dendritic growth and corrosion. Dendritic growth of more than 25 % of original spacing is considered a failure. 3.0 Packaging and Shipping Qualitek Paste Flux is packed into polypropylene plastic containers with insert to minimise the exposure of solder paste. They are shipped in polystyrene foam box with ice packs to prevent higher than 35 C temperature exposure and to optimise paste flux performance. 4.0 Shelf Life and Storage Shelf life of PF600 is 1 year when un-opened container is stored under refrigerating condition, recommended between 2-10 C. Storage below freezing temperature (below 0 C) is not recommended and may jeopardise the rheology characteristics upon thawing.