Technical Library | 2018-09-21 10:12:53.0
Moisture accumulates during storage and industry practice recommends specific levels of baking to avoid delamination. This paper will discuss the use of capacitance measurements to follow the absorption and desorption behaviour of moisture. The PCB design used in this work, focused on the issue of baking out moisture trapped between copper planes. The PCB was designed with different densities of plated through holes and drilled holes in external copper planes, with capacitance sensors located on the inner layers. For trapped volumes between copper planes, the distance between holes proved to be critical in affecting the desorption rate. For fully saturated PCBs, the desorption time at elevated temperatures was observed to be in the order of hundreds of hours. Finite difference diffusion modelling was carried out for moisture desorption behaviour for plated through holes and drilled holes in copper planes. A meshed copper plane was also modelled evaluating its effectiveness for assisting moisture removal and decreasing bake times. Results also showed, that in certain circumstances, regions of the PCB under copper planes initially increase in moisture during baking.
Technical Library | 2022-09-12 14:07:47.0
Unique component handling issues can arise when an assembly factory uses highly-moisture sensitive surface mount devices (SMDs). This work describes how the distribution of moisture within the molded plastic body of a SMD is an important variable for survivability. JEDEC/IPC [1] moisture level rated packages classified as Levels 4-5a are shown to require additional handling constraints beyond the typical out-of-bag exposure time tracking. Nitrogen or desiccated cabinet containment is shown as a safe and effective means for long-term storage provided the effects of prior out-of-bag exposure conditions are taken into account. Moisture diffusion analyses coupled with experimental verification studies show that time in storage is as important a variable as floor-life exposure for highly-moisture sensitive devices. Improvements in floor-life survivability can be obtained by a handling procedure that includes cyclic storage in low humidity containment. SMDs that have exceeded their floor-life limits are analyzed for proper baking schedules. Optimized baking schedules can be adopted depending on a knowledge of the exposure conditions and the moisture sensitivity level of the device.
Industry Directory | Manufacturer
Design and Manufacture Desiccant Dry Cabinets for low humidity storage and baking of moisture sensitive components, PCBs, electronic materials, lab samples, digital media and medical devices.
Salvage indispensible Ball Grid Arrays. Artek Manufacturing will: *Clean and Bake out all contaminants and moisture *Clean out all exsisting Solder *Replace solder spheres according to manufacture's specs *Bake out BGA prior to packing in MSD package
New Equipment | Board Handling - Storage
The Dr.Storage T40W are plug and play, fully auto dry cabinets which can bake at a stable 40℃ and maintain a consistent The T40W Baking Cabinets Series has a double wall design to ensure it maintains a stable According to J-STD-033B, using a T40W
Industry Directory | Consultant / Service Provider / Manufacturer
Specializing in SMD, AX, & RAD component tape & reel packaging, Lead forming, baking and hot solder dipping.
Industry Directory | Consultant / Service Provider / Distributor / Manufacturer
The leader in component automation preparation since 1983. Surface mount, axial & radial tape and reel, programming, baking, distribution of all materials used in these processes. ISO9001-2008, WBE
Industry Directory | Consultant / Service Provider / Distributor / Manufacturer
OX3.com provides engineering, processing and wholesaling of packaging required for the storage, transport, or handling of electronic devices and components. These are typically tapes, trays, tubes, totes, reels or other fixtures.
Industry Directory | Consultant / Service Provider / Equipment Dealer / Broker / Auctions / Manufacturer / Manufacturer's Representative
Moisture-proof Humidity&Drying Solutions Our company is specialized in manufacturing dry cabinet.drying oven.We have Dry Cabinet,Nitrogen Cabinet,Baking Cabinet,Air Blast Drying Oven and Vacuum Oven.
Career Center | , South Jersey USA | Production
I know this has nothing to do with electronics, but if any of you in New Jersey, or Philly, want to start your own Italian Deli Bakery business, here's a chance to get into a restaurant. I wish I had a company that would let me sell them products o
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