General Description
Reflowing assemblies using solder paste is the heart of the SMT process. To have the correct profile assures components, boards, and solder joints are not damaged and reliable solder connection is a result.
It is very important to learn about various types of reflow profiles. The traditional profiles are being replaced in instances with new types. Profiles are essential for establishing and maintaining processes. With new types of products changes to reflow profiles may be required as well as for new types of solder such as lead-free.
In this course you learn all about the terminology, types of profiles, basic types of ovens, measurements and how to setup and take the profiles, and the problems you will see on boards if the profile is not optimum or drifts and starts causing problems.
Target Audience
The course is suitable for a general audience but will have special applicability to manufacturing engineers, product engineers, and production/assembly personnel.
Course Prerequisites
There is no prerequisite for this course.
Author and Subject Matter Expert
The author and subject matter expert is Mr. James C. Blankenhorn, the co-founder and current president of TechEdgeOnline.com. His experience includes 33 years in electronics, 10 years in semiconductor design and management for TI, Motorola and Honeywell. He has 20 years in managing start-ups including Test International, AWI and SMT Plus. He held the position of VP for Jabil Circuit during a period of rapid growth from $100M to $400M. Mr Blankenhorn holds a Bachelor of Science in Electrical Engineering degree from Arizona State University and is a founding member of the SMTA organization. He has authored over 20 books on SMT and related technologies. He is a featured speaker at many conferences and seminars.
System Requirements
- High speed Internet Connection (DSL, cable, ISDN 128)
- Browser: Explorer 4.01 Service Pack 2 (or greater), or Netscape 4.7 (or greater).
- Explorer 5 is recommended
- Flash 4 or greater plug-in
- 16 bit colour, 800 x 600 resolution (minimum requirement)
- Audio card (optional)
- 200 megahertz minimum, 300 megahertz recommended
- 32 RAM minimum, 64 RAM recommended
- 50 mb of available disk cache space
Detailed Course Outline
Module 1: Introduction
Topics covered:
- State what reflow means.
- State the different ways heat can be generated.
- State what infrared is.
- State what infrared reflow is.
- State the equation for heat transfer for infrared heat.
- State what is new about infrared systems.
- State the advantages for infrared reflow.
- Describe forced convection reflow.
- State what oven zones are.
- State the equation for convection reflow heat transfer.
- State the advantages and disadvantages for convection reflow.
- Describe a vapor phase reflow system.
- State the advantages and disadvantages for vapor phase reflow.
- Describe conductive heating.
- State the advantages and disadvantages for conductive reflow.
- State how boards are transported through a reflow system.
- Describe what bottom heating is and what is does.
- Describe what topside heating is and what is does.
- State what the parts of a reflow profile are.
- State what the preheat zone is.
- State what the soak zone is and what it does.
- State what the reflow zone is and what it does.
- State what the peak temperature should be.
- State what the cooldown zone is and what it does.
- Describe a RTR profile.
- State the advantages to a RSR profile over a RTR profile.
- State what effect conveyor speed has on the profile.
- State what a thermal profile is.
- State when thermal profiles are to be run.
- State where reflow profiles come from.
- State what profile control limits are.
- State what the profile control limit values are.
- State what effect board spacing has on a profile.
- State the defects caused by reflow profile problems.
- State how solder balls are created by reflow profiles.
- State what wetting is and how to fix it.
- State what deficient solder is and how profiles cause them.
- State what tombstoning is and how profiles cause them.
- State what voids are and how profiles cause them.
- Describe dull and grainy solder connections and how profiles cause them.
- State what causes cracked capacitors during reflow.
- State what prevents wetting to leads during reflow.
- State what charred residue is and how profiles cause it.
- State how board density affects profiles.
- State what the effects packages have on profiles.
- State what the options are for running profiles.
- List the steps for manual profiling.
- Describe what a thermocouple is.
- State where to place thermocouples.
- State how to attach thermocouples.
- Describe how a manual profiler works.
- Describe internal profile systems
- State what effect nitrogen has on reflow.
- State what documentation is needed for reflow profiles.
- Summarize what was learned in the reflow profile course.