What is PCB Baking? Why do we need it?

PCB baking is one of the hot topics when discussing PCB. Without the innovation of the printed circuit board, most of the tech and electrical items we utilize today would not be conceivable (PCB). PCBs worked to minimize the size of an electrical device. And they also helped to reduce the price of the product. The Printed Circuit Board is the most vital component in an electrical circuit. Every electrical device, from mobile phones to PCs, contains at least one PCB.

It should not be required to bake printed boards prior to standard and surface mount installation. Many boards get baked for historical purposes: An issue was handled by introducing a baking phase. And it became a part of the production process. Baking is also done in response to client requests, owing to the item’s expense and technological level. PCB baking can reduce the risk of delamination on inferior circuit boards.

What is PCB baking?  

PCB baking is a technique for removing moisture from PCBs. Moisture can happen when the top of a PCB gets colder than its airflow. Moisture gets stuck in the printed circuit board as a response to this. If moisture remains on the PCB, it can develop into water vapor/steam and spread throughout several PCB processing phases, causing harm to the panel or circuit breakdown.

The quantity of moisture that a PCB absorbs gets determined by the composite substance as it gets utilized in the PCB. Polyimide flex and stiff materials, for instance, can retain more moisture than FR4 panels. The PCB baking procedure is not an easy task.

The PCB in the oven is typically kept at a temperature of 100 to 130 °C during the PCB Baking process. The heat can cause the moisture on the surface to evaporate. Therefore, it is critical not to overheat the board or bake it for an extended period since this might cause damage.

Metrics of weight increase and decrease can get used to seeing if the condensation on the circuit board has dissipated. One of the primary goals of PCB baking is to avoid delamination by preventing moisture outgassing via copper in via gaps. Condensation can collect in gaps or at the contact between the epoxy and the composite on poorly bonded multi-layer panels, causing delamination or measling.

Why are PCBs baked?

PCB baking procedure is not an easy process, as you may well know. Let’s look at why PCBs get baked.

The major factors responsible for baking circuit boards are to prevent condensation from escaping through the copper plating is coated through gaps and to prevent outgassing. It results in blowholes, pinholes, or sunk soldering margins throughout hand or mechanized soldering procedures. Another reason to bake boards is to keep them from delaminating or weaseling throughout soldering or reworking. 

When drilling or other mechanical operations, the contact between the glass fabric and the epoxy might get damaged, adherence should not be a problem nowadays considering the quality of the surface treatment or copper layers.

Do we need to bake all printed circuit boards?

Moisture Removal from the PCB is critical for any PCB producer. The PCBs can get baked to accomplish this. If moisture is not adequately eliminated from the board before it gets installed in the equipment, it may cause the board to malfunction.

It is not usually necessary to bake PCBs. It is preferable to keep moisture out of the board directly. It is something that may get accomplished right at the start of the PCB design and production process. Condensation is more or less likely a problem depending on the PCB design. The PCB lamination assessment must get carried out in a temperature-controlled setting. It generally suffices to dry the board.

How do we bake PCBs at Absolute Electronics?

Baking temperature: 120±5℃

Before installation, there is no need to bake PCBs if they are inside two months of manufacture and get adequately closed. Likewise, there is no need to bake PCBs if they get made within five days. As per IPC-1601, if the circuit boards are opened and put in heat and moisture contained situation (30°C/60 percent RH), the specified temperature and time length to bake them before they proceed on the production line are as follows.

• After storing the circuit boards for 5 to 60 days, they must get roasted for an hour.
• PCBs that have gotten held for 2 to 6 months must get baked for 2 hours.
• PCBs held for 6 to 12 months must get baked for 4 hours.
• PCBs that have gotten held for more than 12 months are considered out of the current and should not get used. Condensation currently corrodes PCB pads, and the solder mask can age or get ruined as a result. In addition, the circuit’s conductance gets diminished, and the circuit’s resistance gets decreases. As a result, we don’t bake them and instead throw them away.

Within five days of baking the PCBs, they should get installed. If they do not get utilized within five days, they will need to get baked again. 

Lots of consideration is to be taken when the PCB is in the oven. The PCB should be about in the center of the oven, between the top (furnace) and bottom (detector). The PCB must be positioned beneath the top detector not to get any heat from the bottom heater IR lamps.

Wrapping up

The term “bake-out” refers to the practice of eliminating volatile components from substances using high-temperature (100 to 125°C) or vacuum before putting them in a situation where the delayed emission of these active chemicals might impede the functioning of a device that uses these components. PCB baking is a complex process. If you want it done quickly, get aid from Absolute Electronics. Absolute Electronics Services attempts to provide extremely robust PCBs as a PCB manufacturing company. They go through several testing steps and careful analysis before certifying it as an authorized product.