The ws888 is water soluble lead free solder paste designed to meet the requirements for reliable solder joints in printed circuit board assemblies. Cr6000 6zone smt convection reflow soldering oven pcba. This application note documents the common solder attach reflow profile for both standard and lead free packages. Alpha offers a variety of solder pastes for lead free pcb assembly that offer high reliability and high throughput applications. The solder paste reflows in a molten state, creating permanent solder joints. This lowering of the melting point may be enough to allow use of a tinlead reflow.
This is a demo of running a lead free board in the r300a oven using the included reflow oven console software and the profile editor. The shelf life of solder paste is generally 6 to 9 months. Pro 1600 is now in a standby mode, ready for a new cycle run. Optimized reflow profiling to minimize voiding kic thermal. After placing all of your surface mount components just hit the reflow button and sit back to enjoy the show. The software comes with 18 profiles for the most common solder. Tinlead alloys reflow profile guidelines the information provided is a guideline only. To give an indication of a temperature profile in practice, here is a screen shot of the software for the. Ultimately, quality requirements should drive the process, not adherence to these guidelines. Best practices reflow profiling for lead free smt assembly indium corporation tech paper authored by. Once the pcba has passed through the oven, the results from the data logger will be downloaded into the chosen oven profiling software and this is where the first real analysis of the profile begins.
Check pcb and component solderability, check quality of solder paste, check reflow profile to solder paste datasheet. Reflow soldering is a process in which a solder paste a sticky mixture of powdered solder and flux is used to temporarily attach one or thousands of tiny electrical components to their contact pads, after which the entire assembly is subjected to controlled heat. For the traditional trapezoidal type profile base on lead free solder paste that bittele uses for smt assembly process. Match solder paste specifications and oven configurations to provide robust process profiles. The solder paste library of your profiling software provides several choices. Typcial solder reflow profile for a lead free snag solder time seconds 0 50 100 150 200 250 300 350 temperature o c 0 25 50 75 100 125 150 175 200 225 250 275 typical maximum minimum figure 2. Each database entry includes the manufacturers recommended solder profile for that specific solder paste formula and identifies critical specifications i.
We discuss the profiling, tools, practical issues, and inspection methods of golden boards, and related tools. We have gathered profiles from various paste manufacturers, but we dont have data on what temperature profiles should be set for heating and cooling zones. Reflow profile for mixed leadfree and leaded circuitnet. How to create the perfect smt reflow oven profile hawker.
These reference guidelines follow the recommendations of the standards ipc7530 for temperature profiling for mass. An alloy that is used as a lead free solder consisting of tin and copper considered to be applicable for wave or re. This library is updated periodically and verified by the solder paste manufactures in most instances. Therefore the max temperature in the curve should be set at solder temperature of the alloy. Solder profiles to be able to solder using a chamber oven like the ecreflowmate it is important to understand that.
A practical approach to reflow profiling by liyakathali. Lead free pastes usually consist of a tin sn, silver ag and copper cu alloy. Profile planner reflow profiling software description. To maintain a soak profile this would be changed as indicated in figure 1.
For some inputs, such as slope, preheat, soak and tal you can define multiples of. What changes are required for using tinlead paste on leadfree circuit boards. The maximum temperature of 300 celsius will allow you to reflow both lead and leadfree solder paste. These reference guidelines follow the recommendations of the standards ipc 7530 for temperature profiling for mass. Your solder paste supplier should be able to give specific details on this. Do not place leadfree bgas with other tinlead components. Ws888 displays previously unseen levels of repeatability and consistency even in a wide range of temperatures 6585f and relative humidity 25% 65% rh. Leadfree smt can be challenging however, this challenge can be reduced if the. Standard reflow profile for standard and leadfree packages. The solder reflow process is based on convection heating, similar to that in your home oven. The aim of the process is to form acceptable solder joints by first preheating the componentspcb solder paste and then melting the solder without causing damage by overheating. It is not possible for the solder paste manufacturer to recommend reflow heater set points as oven vary widely in their performance and zone configuration, plus every electronic assembly has differing thermal mass and required careful profile tuning, especially when dealing with lead free. The introduction of higher leadfree process temperatures and a reduction in solder paste deposit volumes require narrower process windows to optimize the reflow profile.
For lead free reflow soldering, a disadvantage of the standard profile is the relative height of the peak of the reflow zone. Preheat temperature min t smin temperature max t smax time t smin to t smax 150. Nl932 displays previously unseen levels of repeatability and consistency even in a wide range of temperatures. In most cases the solder paste determines the reflow profile used. Users are advised to optimize their own board level parameters to get proper reflow outcome. Process materials temperature time description interval 1. With the soak zone at 150 c and the reflow zone at 245 c typical value for leadfree reflow soldering, the temperature rise from soak zone to reflow zone is 95 c. A profile is then executed as per the preprogrammed parameters. Per package qualification maximum number of reflow can be done on microsemi soc products group packages is 3. Not only are the electronics components and the pwb at risk due to the higher reflow.
Leadfree solder paste reflow profile supplement aim solder. This paste offers an excellent open time, extended abandon time and good soldering activity with all surface finishes. Leadfree board assembly reflow profile example leadfree bga solder joint assembly evaluation, rev. Soldering will include information on acceptable and defective leadfree solder joints. The recommended reflow profile is provided as a guideline. Rohs compliant solder reflow profile smd trimpot products. Lead free hot air level melts at lead free temperatures, therefore a normal tinlead reflow profile may not melt the surface finish. Tools needed to setup a solder paste reflow profile. We have now received the soldering profile, datasheets for the solder pastes and the temperature calibration protocol for the reflow oven. Reflow oven profile plotter utility is a freeware application to graph temperature vs time data sent typically from a homemade reflow oven controller eg. Reflow soldering is the most widely used method of attaching surface mount components to printed circuit boards pcbs.
Lead free bga components require a lead free reflow profile in order to melt and merge with the solder paste. Smt2011 desktop automatic leadfree reflow oven power. This section outlines the differences between conventional tin lead reflow soldering and pb free soldering. Users are advised to optimize their own pcb level design in order to obtain proper solder reflow and.
The reflow soldering process for pb free components is very similar to the conventional eutectic tin lead solder reflow process. Koorithodi, indium corporation in the leadfree era, thermal profiling has a critical role in the smt assembly process. Software constantly monitors actual ramp up rates and temperature inside an oven to the programmed values for accuracy. For lead free soldering what should be our baseline for lowmedium density boards. Allen continued, finding the correct recipe for a reflow oven to produce a pcb within the current, very tight, leadfree process windows could take significant amounts of both resources and time. Reflow profiling for lead free solder alloys has been. A novel method of making a copper sandwich to simulate under lead and under component environs during reflow has been developed and is discussed in detail. Reading your profile via profile software profiling guru. Preheat usually refers to increasing the temperature from normal temperature to 150 c and from 150 c to 180 c. The solder profile can also be influenced by high component density, heavy copper foil, and other unusual conditions. Standard reflow profile fo r standard and leadfree packages the reflow here in provided is for reference only. Leaded vs lead free profiles global leader in solder and. Introduction process temperatures and a reduction in solder paste deposit volumes require narrower process windows to optimize the reflow profile. Modern software tools allow a profile to be captured, then automatically.
The maximum temperature of 300 celsius will allow you to reflow both lead and lead free solder paste. Best practices reflow profiling for leadfree smt assembly. Reflow soldering profile setup and optimisation software. The profile planner is an microsoft excel workbook application that allows you to match solder paste specifications and oven specifications. The optimization process for reflow starts in the early stages of setting up a product for solder reflow. Volatiles released during reflow of solder paste are trapped within solder and not allowed time to escape, vias within pads contributing to air pockets. At the completion of a reflow cycle, the tray automatically exits from a heating chamber.
Pdf optimisation of reflow profile of surface mount assembly. With the introduction of lead free solder alloys, the effect of voids on. On page 3, figure 1 show a typical solder reflow profile for a pbfree snag solder and figure 2 shows a. Optimizing reflow profiling in leadfree smt assembly. Typcial solder reflow profile for a lead tin pbsn solder. How to solder qfn mlf chips using hot air without solder paste and stencils duration. Download serial profile plotter for reflow ovens for free.
Electronics manufacturers provide recommended thermal profiles that serve as a good starting. Use the standard tinlead reflow profile with peak reflow of 210. Leadfree challenges on solder paste understanding reflow profile optimizing the reflow process. Increasing metal content reduces the tendency to slump and reduces the tack life of the paste, while the solder balling performance improves. Reflow oven profilers and wave soldering profilers accurately record and log your reflow solder profile, reflow oven temperature profile, or wave solder machine thermal profile with thermal profilers from manncorp. Kic works with any solder paste manufactures to build the solder paste library that is present in the kic software. Temperature of leadpad junction rohs compliant solder reflow profile smd trimpot products specifications are subject to change without notice.
The reflow oven is used primarily for the reflow soldering of surface mount. Technical bulletin alpha solder paste om 338 series technical bulletin en alpha solder paste om 535 technical bulletin cn alpha solder paste om550 technical bulletin. The temperature profile of the solder paste would be hard to duplicate in a larger oven. Alpha offers a variety of solder pastes for leadfree pcb assembly that offer high reliability. How to create the perfect smt reflow oven profile jjs manufacturing. Leaded vs lead free profiles global leader in solder. Solder reflow the assembly of surfacemount devices smds onto a printed circuit board pcb consists of the following steps. I am about to try my first reflow skillet soldering job, and as i look at the available types of solder paste i see there are lead free pastes with much lower melting temperatures than others. Poor component solderability, poor quality solder paste, incorrect reflow profile, poor compatibility of pcb finish, solder type, and component termination material.
Heating may be accomplished by passing the assembly. Best practices reflow profiling for lead free smt assembly. Defects caused by improper design of surfacemount pcbs, solder paste printing and component mounting will eventually find expression in soldered products. Profiling software tools powerful process analysis and optimisation tools. In comparison, a batch oven allows for some flexibility in the profiles. Your profile will depend upon many factors including customer requirements, component limitations, oven characteristics, board layout, etc. Lead free reflow profile recommended reflow profile for kester solder paste formulations containing the sn96. Lead free component reflowed with leaded solder paste page 1. Reflow this is the stage where the temperature within the reflow oven is increased above the melting point of the solder paste causing it to form a liquid. It is not possible for the solder paste manufacturer to recommend reflow heater set points as oven vary.
Suitable temperature curve of leadfree solder engineering. For leadfree reflow soldering, a disadvantage of the standard profile is the relative height of the peak of the reflow zone. Leadfree reflow profile recommended reflow profile for kester solder paste formulations containing the sn96. Reflow soldering is a main method to form solder joints on smt basepanels and so is a core technology in smt process. The library however does not at any one time contain all information about all possible solder pastes. Actual solder process requirements will be determined by the customer, based on the specific application. Some tin lead solder pastes can withstand a lead free profile, but some cannot. In general, solder pastes can be divided into two groups based on the composition of the solder. Arduino based via serial port to a pc or notebook running windows 7. This paper will address the optimization of pb free soldering conditions, with a focus on differences between sn pb and pb free soldering. Customers should verify actual device performance in their specific applications. Product description the nl932 is a noclean lead free solder paste designed to meet the requirements for reliable solder joints in printed circuit board assemblies. The time the solder is held above its melting point time above liquidus is important to ensure correct wetting occurs between components and pcb. It has been designed to be userfriendly for both temperature profiling novices and experts alike.
Nte electronics sw0210 noclean solder wick, 4 blue. There are four stages to the solder reflow profile. Ws888 water soluble lead free solder paste pentalogix. Allow more time when solder is molten for volatiles to escape, modify stencil design to allow more pathes for volatiles to escape, consider alternative lowvoiding solder pastes, plug vias in pcb. The printing performance of solder paste depends in part on the metal content, solder alloy and the solder particle size range. Solder profiles and oven parameters for the ecreflowmate. The oven also includes userfriendly software and rs232 communication cable in case you would like to create an unlimited amount of profiles and save them on your computer and watch your profile come to life on your monitor. How to choose a pcb reflow oven for efficient pcb solder. After tinlead components have been reflowsoldered, use selective soldering with a laser to place and solder all leadfree bgas. The nc676 noclean solder paste is a new generation halide free, rosinbased chemistry designed to provide a previously unseen level of repeatability and consistency to the printing process. Nov 04, 2019 download serial profile plotter for reflow ovens for free. Leadfree solder paste pf 606p version 1, 0715 basic overview snag3.
Typical solder process example generic reflow profiles. Use a smaller toaster oven, get one from a second hand store. Pdf evaluation of reflow ovens for leadfree soldering. The tinlead solder in the solder paste alloys with the leadfree hot air level finish which reduces the overall melting point. The board is processed as lead free, but this board is exempt from rohs. Jun 02, 2016 best practices reflow profiling for lead free smt assembly indium corporation tech paper authored by. Lead free printedcircuitboard pcb assemblies were carried out using different foot print designs on pcbs, solder paste deposition volume and reflow profiles. An alloy that is used as a lead free solder consisting of tin, silver and copper as the main constituents. Jun 15, 2012 this is a demo of running a lead free board in the r300a oven using the included reflow oven console software and the profile editor. Most lead based solder pastes consist of an allow of tin sn and lead pb.
There are four stepszones to this process preheating, soaking, reflow and cooling. Maximum rising slope ramp rate maximum falling slope cooling rate preheat. Use our recommended heating profile, or manually adjust the temperature for complete control. Solder profile for lead free reflow process figure 1 classification reflow profile for smt components refer to ipcjedec jstd020e table 1 classification reflow profiles profile feature pb free assembly average rampup rate t smax to t p 3c second max. Often, you can use the same equipment set and process steps used for eutectic soldering for pb free soldering. While this may be said of leadtin solder pastes used previously, leadfree. Typical reflow temperature curves using snpb eutectic solders are usually divided into four sections. The reflow oven temperature profile is suited for characteristics of a particular. Utility for plotting data from homemade reflow ovens via serial port. At the heart of all solderstars profiling solutions lies the powerful and intuitive profile central software suite, regarded by many as the best available. With the soak zone at 150 c and the reflow zone at 245 c typical value for lead free reflow soldering, the temperature rise from soak zone to reflow zone is 95 c. Calibrated profiler with at least four thermal couple ports and thermal couple wires populated circuit board that represents the one going to be soldered a print or description of the proper profile for the solder paste being used.
Reflow soldering is a process by which the solder paste is heated and changes to a molten state in order to connect components pins and pcb pads together. Look up the temperature profile for the paste you have, you need to time the temperature profile to that of the solder, you will get better results. The eutectic solder with a 93% diffusibility range, and the leadfree solder with a 73%77% diffusibility range. The dwell temperature of the solder alloy needs to be reached at all solder joints present on the board. The temperature of the hot air in the oven follows a thermal profile that provides the optimum heat and cooling rate for the given solder paste and components. A generic leadfree solder reflow profile is provided as a guideline when using our products that feature the new snagcu solder balls. Sold by chip quik and ships from amazon fulfillment. Solder spread test solder paste stencil opening was 1. Reflow soldering is a process in which a solder paste is used to temporarily attach one or. The aim of the process is to form acceptable solder joints by first preheating the componentspcbsolder paste and then melting the solder without causing damage by overheating. With a 550w heater, the vone can reach reflow temperatures in under a minute. This method has enabled quantitative solder paste void analysis for lead free and specialty paste development and process refinement.
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