UV LED Curing in Electronic Applications: When to convert from spot curing to flood curing

Spot curing is ideal for precision curing of a small diameter area, up to about 10 mm, either manually or in an automated process. Like other UV systems, spot curing systems are now available with UV LED sources which offer the following advantages over traditional mercury arc lamps sources:

  • more energy efficient
  • more consistent output for a more consistent process
  • transmits less heat onto the substrate
  • lasts up to 10 times longer

In fact, over half of all UV spot cure systems sold globally use UV LED technology.

In electronics applications spot curing is commonly used for bonding miniature components such as compact camera, speaker, and hearing aid components to components on printed circuit boards (PCBs), as well as wire bonding, component masking and potting. However, if you need higher reliability, throughput and quality with lower operating costs UV LED flood curing is likely a better option if you have:

  • a single component, assembly or PCB that needs multiple spot cures


  • one or only a few spot cures on a single part, but could process many parts together in batches or on a continuous line

One example is a PCB assembly process which currently uses 3 or more spot cures to attach components. By converting to a batch process using a UV LED curing chamber, or a continuous process using a UV LED curing conveyor, the PCB manufacturer can process boards at a higher production rate. Instead of using multiple UV LED spot

curing systems, the boards can cure under one UV LED system designed to cover the needed cure area. And if using handheld spot cure units, most manufacturers see a significant improvement in process consistency that results in improved product quality and reduced rework when they convert to a flood UV LED curing process.

Conveyor belt UV LED

Like the UV LED spot cure technology, the UV LED arrays for flood curing are instant on/off. Some UV LED array designs offer the ability to operate only a portion of the array and dimming to UV output levels needed, saving energy costs while meeting your specific processing needs. For example, Noblelight’s  Semray UV LED system comes in 3-inch wide segments, or modules, that can span across a conveyor or curing chamber to expose a large area. However, when processing narrower parts, individual segments can be turned off to match the narrower width. Learn more about our  UV LED benchtop conveyor solution .

Test to determine ROI

The best way to determine the production rate and quality improvements resulting from a conversion from UV LED spot curing to flood curing for your specific process is to run tests. Noblelight’s UV curing experts can assist with testing in their application centers or by loaning out UV LED curing systems for testing on your production line. Using this test data you can easily calculate the return on investment (ROI) to decide whether converting your UV LED spot curing process to a flood curing process makes sense. Learn more about our  UV curing testing capabilities and assistance.