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Hi-

I have a couple of questions related to assembly of fine-pitch components:

1) I would like to confirm your capability in terms of component pitch.
I have QFP with nominal 0.4mm pitch (pin center to pin center) and 0.2mm pin width - leaving 0.2mm pin spacing (edge-to-edge).Also some LGA, most critical one has 0.2mm pin spacing (edge-to-edge).
Can you handle that ?

2) If so - regarding solder mask :
you require 0.075mm min clearance between any PCB pad and solder mask (dimension D, "minimum gap to solder surface"),
so when the chip has 0.2mm spacing between pins that would leave only 0.2-2x0.075 = 0.05mm solder mask web between the pins
-- which violates your requirement for 0.1mm minimum width of solder mask (dimension A, "minimum soldermask bridge").
Then what do you recommend :
- do without solder mask between these fine-pitch pins (but risk of bridging ?)
- decrease the solder mask to solder pad clearance to 0.05 mm, to leave 0.1mm available for solder bridge between pins (but risk of solder mask encroaching solder pad ?)
- accept a soldermask bridge down to 0.05mm (but risk of soldermask bridge absence?)
Please advise.

Thanks