For lead free reflow soldering, a disadvantage of the standard profile is the relative height of the peak of the reflow zone. Smt2011 desktop automatic leadfree reflow oven power. These reference guidelines follow the recommendations of the standards ipc 7530 for temperature profiling for mass. Leadfree board assembly reflow profile example leadfree bga solder joint assembly evaluation, rev. 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. Your profile will depend upon many factors including customer requirements, component limitations, oven characteristics, board layout, etc. Use the standard tinlead reflow profile with peak reflow of 210. 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. Users are advised to optimize their own pcb level design in order to obtain proper solder reflow and. Reflow soldering profile setup and optimisation software.
To give an indication of a temperature profile in practice, here is a screen shot of the software for the. 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. What changes are required for using tinlead paste on leadfree circuit boards. Optimized reflow profiling to minimize voiding kic thermal. We discuss the profiling, tools, practical issues, and inspection methods of golden boards, and related tools. It is not possible for the solder paste manufacturer to recommend reflow heater set points as oven vary. Lead free reflow profile recommended reflow profile for kester solder paste formulations containing the sn96.
The maximum temperature of 300 celsius will allow you to reflow both lead and lead free solder paste. Koorithodi, indium corporation in the leadfree era, thermal profiling has a critical role in the smt assembly process. At the completion of a reflow cycle, the tray automatically exits from a heating chamber. The shelf life of solder paste is generally 6 to 9 months. These reference guidelines follow the recommendations of the standards ipc7530 for temperature profiling for mass. Leaded vs lead free profiles global leader in solder.
Pdf optimisation of reflow profile of surface mount assembly. Leadfree challenges on solder paste understanding reflow profile optimizing the reflow process. To maintain a soak profile this would be changed as indicated in figure 1. Alpha offers a variety of solder pastes for lead free pcb assembly that offer high reliability and high throughput applications. 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. Kic works with any solder paste manufactures to build the solder paste library that is present in the kic software. Leadfree reflow profile recommended reflow profile for kester solder paste formulations containing the sn96. How to choose a pcb reflow oven for efficient pcb solder. Temperature of leadpad junction rohs compliant solder reflow profile smd trimpot products specifications are subject to change without notice. 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. The solder paste reflows in a molten state, creating permanent solder joints. On page 3, figure 1 show a typical solder reflow profile for a pbfree snag solder and figure 2 shows a.
Electronics manufacturers provide recommended thermal profiles that serve as a good starting. The profile planner is an microsoft excel workbook application that allows you to match solder paste specifications and oven specifications. Preheat temperature min t smin temperature max t smax time t smin to t smax 150. 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 practical approach to reflow profiling by liyakathali. How to solder qfn mlf chips using hot air without solder paste and stencils duration.
Suitable temperature curve of leadfree solder engineering. The temperature profile of the solder paste would be hard to duplicate in a larger oven. Leaded vs lead free profiles global leader in solder and. Cr6000 6zone smt convection reflow soldering oven pcba. Leadfree solder paste reflow profile supplement aim solder. Ultimately, quality requirements should drive the process, not adherence to these guidelines.
A profile is then executed as per the preprogrammed parameters. How to create the perfect smt reflow oven profile jjs manufacturing. Lead free pastes usually consist of a tin sn, silver ag and copper cu alloy. Users are advised to optimize their own board level parameters to get proper reflow outcome. Lead free bga components require a lead free reflow profile in order to melt and merge with the solder paste. Volatiles released during reflow of solder paste are trapped within solder and not allowed time to escape, vias within pads contributing to air pockets. The eutectic solder with a 93% diffusibility range, and the leadfree solder with a 73%77% diffusibility range. In general, solder pastes can be divided into two groups based on the composition of the solder.
Tools needed to setup a solder paste reflow profile. With the introduction of lead free solder alloys, the effect of voids on. Therefore the max temperature in the curve should be set at solder temperature of the alloy. Nl932 displays previously unseen levels of repeatability and consistency even in a wide range of temperatures.
Reading your profile via profile software profiling guru. Solder reflow the assembly of surfacemount devices smds onto a printed circuit board pcb consists of the following steps. In most cases the solder paste determines the reflow profile used. Your solder paste supplier should be able to give specific details on this. For some inputs, such as slope, preheat, soak and tal you can define multiples of. Reflow profiling for lead free solder alloys has been. 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. Maximum rising slope ramp rate maximum falling slope cooling rate preheat. Defects caused by improper design of surfacemount pcbs, solder paste printing and component mounting will eventually find expression in soldered products. Software constantly monitors actual ramp up rates and temperature inside an oven to the programmed values for accuracy. Tinlead alloys reflow profile guidelines the information provided is a guideline only. For lead free soldering what should be our baseline for lowmedium density boards.
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 introduction of higher leadfree process temperatures and a reduction in solder paste deposit volumes require narrower process windows to optimize the reflow profile. This paste offers an excellent open time, extended abandon time and good soldering activity with all surface finishes. Profile planner reflow profiling software description. It has been designed to be userfriendly for both temperature profiling novices and experts alike. The solder profile can also be influenced by high component density, heavy copper foil, and other unusual conditions.
An alloy that is used as a lead free solder consisting of tin, silver and copper as the main constituents. 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. Soldering will include information on acceptable and defective leadfree solder joints. Solder profiles to be able to solder using a chamber oven like the ecreflowmate it is important to understand that. Leadfree solder paste pf 606p version 1, 0715 basic overview snag3. Rohs compliant solder reflow profile smd trimpot products. With a 550w heater, the vone can reach reflow temperatures in under a minute.
Reflow soldering is a process in which a solder paste is used to temporarily attach one or. Alpha offers a variety of solder pastes for leadfree pcb assembly that offer high reliability. 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. Leadfree smt can be challenging however, this challenge can be reduced if the. Standard reflow profile for standard and leadfree packages.
Reflow soldering is the most widely used method of attaching surface mount components to printed circuit boards pcbs. The library however does not at any one time contain all information about all possible solder pastes. How to create the perfect smt reflow oven profile hawker. Reflow profile for mixed leadfree and leaded circuitnet. The reflow soldering process for pb free components is very similar to the conventional eutectic tin lead solder reflow process. Reflow oven profile plotter utility is a freeware application to graph temperature vs time data sent typically from a homemade reflow oven controller eg. Lead free printedcircuitboard pcb assemblies were carried out using different foot print designs on pcbs, solder paste deposition volume and reflow profiles. Use a smaller toaster oven, get one from a second hand store. Profiling software tools powerful process analysis and optimisation 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. The recommended reflow profile is provided as a guideline. Optimizing reflow profiling in leadfree smt assembly. Most lead based solder pastes consist of an allow of tin sn and lead pb.
Lead free component reflowed with leaded solder paste page 1. For leadfree reflow soldering, a disadvantage of the standard profile is the relative height of the peak of the reflow zone. Typcial solder reflow profile for a lead tin pbsn solder. For the traditional trapezoidal type profile base on lead free solder paste that bittele uses for smt assembly process. Heating may be accomplished by passing the assembly. Process materials temperature time description interval 1. Ws888 water soluble lead free solder paste pentalogix. There are four stages to the solder reflow profile. Typical reflow temperature curves using snpb eutectic solders are usually divided into four sections. This section outlines the differences between conventional tin lead reflow soldering and pb free soldering. 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. Best practices reflow profiling for lead free smt assembly. After tinlead components have been reflowsoldered, use selective soldering with a laser to place and solder all leadfree bgas. This method has enabled quantitative solder paste void analysis for lead free and specialty paste development and process refinement.
A generic leadfree solder reflow profile is provided as a guideline when using our products that feature the new snagcu solder balls. Reflow soldering is a main method to form solder joints on smt basepanels and so is a core technology in smt process. Best practices reflow profiling for leadfree smt assembly. Each database entry includes the manufacturers recommended solder profile for that specific solder paste formula and identifies critical specifications i. 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. Not only are the electronics components and the pwb at risk due to the higher reflow. The time the solder is held above its melting point time above liquidus is important to ensure correct wetting occurs between components and pcb. There are four stepszones to this process preheating, soaking, reflow and cooling. Pdf evaluation of reflow ovens for leadfree soldering. Lead free hot air level melts at lead free temperatures, therefore a normal tinlead reflow profile may not melt the surface finish. Download serial profile plotter for reflow ovens for free.
Utility for plotting data from homemade reflow ovens via serial port. 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. Increasing metal content reduces the tendency to slump and reduces the tack life of the paste, while the solder balling performance improves. Pro 1600 is now in a standby mode, ready for a new cycle run. Standard reflow profile fo r standard and leadfree packages the reflow here in provided is for reference only. Do not place leadfree bgas with other tinlead components. 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. Nte electronics sw0210 noclean solder wick, 4 blue. Often, you can use the same equipment set and process steps used for eutectic soldering for pb free soldering. Match solder paste specifications and oven configurations to provide robust process profiles. In comparison, a batch oven allows for some flexibility in the profiles.
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. The printing performance of solder paste depends in part on the metal content, solder alloy and the solder particle size range. Introduction process temperatures and a reduction in solder paste deposit volumes require narrower process windows to optimize the reflow profile. This application note documents the common solder attach reflow profile for both standard and lead free packages. At the heart of all solderstars profiling solutions lies the powerful and intuitive profile central software suite, regarded by many as the best available. 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. 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. While this may be said of leadtin solder pastes used previously, leadfree. The information provided in this application note is for reference only. 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.
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. The dwell temperature of the solder alloy needs to be reached at all solder joints present on the board. Use our recommended heating profile, or manually adjust the temperature for complete control. The maximum temperature of 300 celsius will allow you to reflow both lead and leadfree solder paste.
Typical solder process example generic reflow profiles. Solder spread test solder paste stencil opening was 1. The board is processed as lead free, but this board is exempt from rohs. After placing all of your surface mount components just hit the reflow button and sit back to enjoy the show. 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.
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. Nov 04, 2019 download serial profile plotter for reflow ovens for free. 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. Ws888 displays previously unseen levels of repeatability and consistency even in a wide range of temperatures 6585f and relative humidity 25% 65% rh. Arduino based via serial port to a pc or notebook running windows 7.
Solder profiles and oven parameters for the ecreflowmate. 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. 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. The optimization process for reflow starts in the early stages of setting up a product for solder reflow. Jun 02, 2016 best practices reflow profiling for lead free smt assembly indium corporation tech paper authored by. The software comes with 18 profiles for the most common solder.
Poor component solderability, poor quality solder paste, incorrect reflow profile, poor compatibility of pcb finish, solder type, and component termination material. The tinlead solder in the solder paste alloys with the leadfree hot air level finish which reduces the overall melting point. Modern software tools allow a profile to be captured, then automatically. Some tin lead solder pastes can withstand a lead free profile, but some cannot. Preheat usually refers to increasing the temperature from normal temperature to 150 c and from 150 c to 180 c. This lowering of the melting point may be enough to allow use of a tinlead reflow. The ws888 is water soluble lead free solder paste designed to meet the requirements for reliable solder joints in printed circuit board assemblies. This paper will address the optimization of pb free soldering conditions, with a focus on differences between sn pb and pb free soldering. The reflow oven temperature profile is suited for characteristics of a particular. The solder paste library of your profiling software provides several choices. Sold by chip quik and ships from amazon fulfillment.
We have now received the soldering profile, datasheets for the solder pastes and the temperature calibration protocol for the reflow oven. Check pcb and component solderability, check quality of solder paste, check reflow profile to solder paste datasheet. The reflow oven is used primarily for the reflow soldering of surface mount. 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. Actual solder process requirements will be determined by the customer, based on the specific application.