Pre-tin QFN package?

Hello, we use the nRF52840 in the aQFN 73 package, 7 x 7 mm. Seeing some production failures with the boards. Examined several boards under robotic X-ray and there are several questionable solder joints around the nRF chip. The assembly house is recommending that we ‘pre-tin’ the chips. This is something a third party does. Does anyone have experience with this procedure? Any recommendations as to who can do it in US?


I’m very sorry but we don’t provide pre tinning service. I’m not at all familiar with this service specifically but a basic google search for “pre tinning services” yielded some results such as:

Custom Tinning Services- Huntsville, AL (

Hope that helps.