What is the surface finish of the nRF52840 (AU over nickel, AU-PD-NI, other)?

[baldrichNI]

We are fine tuning our manufacturing process placing the nRF52840 and would like to know what surface finish is used on the chip. I was not able to find this in the spec.

[Nordic QA]

Dear Bekah,

LF material is Cu, then plating Ni, Pd and Au.
Ni: 0.001~0.00254
Pd: 0.00002~0.00015
Au: 0.000010 Min.

or in inch

Ni: 0.0000394~0.0001
Pd: 0.0000008~0.0000059
Au: 0.0000004 Min
  Unit: inch

Kind Regards, Jos

Jos van de Giesen, Field Quality Manager

 

[baldrichNI]

Thanks!