Hi Lam,



We have been laser drilling down to the third level for some time now.  I do not however, suggest you use RCC, but Epoxy Thermount in the core cap mode.  I can send you a drawing of a potential lay-up if you wish.



Larry Burgess





----- Original Message ----- 

From: Lam, Patrick <[log in to unmask]>

To: <[log in to unmask]>

Sent: Monday, August 14, 2000 14:27

Subject: [TN] Microvia Connecting Two RCC Layers





> We would like to add two RCC layers each to the top and bottom of an 4-layer

> FR-4 board. Does anyone have experience or suggestion to handle multi RCC

> layers? We would like to have microvia connecting the top RCC layer to the

> outer FR-4 layer, as well as having some microvias connecting both the RCC

> layers to the outer FR-4 layer. Ideally, we would like to have microvias

> connecting three layers without offset drilling. Is it possible to do the

> following: Add one RCC layer, finish the microvia process, add another RCC

> layer on top of the RCC layer, drill microvia at the same drill location as

> the previous RCC layer.

> 

> Any information would be highly appreciated.

> 

> Patrick Lam

> Glenayre R&D

> Phone:(604)293.4392

> 

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