[PCB_FORUM] Re: copper filling of micro vias.

I have 2 shops telling me that they can't do it.  They can fill the inner
blind via and the core, but not the L1-L2 via.

I'm using a construction 2+8+2 construction w/ stack vias and a core from
L2-L7.

Can anyone recommend a good fab for HDI designs?

Thanks,

-oscar

On Mon, May 19, 2008 at 3:25 PM, Douglas Stanley <dstanley@xxxxxxxxxxxx>
wrote:

>  We use a 5 mil drill and a 10 mil pad on both inner and outer layers.
>
>
>  ------------------------------
> *From:* icu-pcb-forum-bounce@xxxxxxxxxxxxx [mailto:
> icu-pcb-forum-bounce@xxxxxxxxxxxxx] *On Behalf Of *O Migs
> *Sent:* Monday, May 19, 2008 3:21 PM
> *To:* icu-pcb-forum@xxxxxxxxxxxxx
> *Subject:* [PCB_FORUM] Re: copper filling of micro vias.
>
> What is your minimum drill size?  We are using 12pad 5drill from L1-L2,
> L2-L3.
>
> Regards,
>
> -oscar
>
> On 5/19/08, Douglas Stanley <dstanley@xxxxxxxxxxxx> wrote:
>>
>>  We do boards every day that are 3 and 3 with microvias in pad. The board
>> shops completely fill the hole with copper and then plate over it. They then
>> planerize the copper so the pad is flat. I think it's pretty standard
>> nowadays. We simply add a note to the fab drawing to plate the microvia
>> closed and to "repad" so the surface is flat.
>>
>>
>> Douglas G. Stanley
>> PC Board Designer, Sr. Staff
>> Broadcom Corporation- Irvine, CA
>> dstanley@xxxxxxxxxxxx
>> (949) 926-5889
>>
>>
>>  ------------------------------
>> *From:* icu-pcb-forum-bounce@xxxxxxxxxxxxx [mailto:
>> icu-pcb-forum-bounce@xxxxxxxxxxxxx] *On Behalf Of *O Migs
>> *Sent:* Monday, May 19, 2008 9:58 AM
>> *To:* icu-pcb-forum@xxxxxxxxxxxxx
>> *Subject:* [PCB_FORUM] copper filling of micro vias.
>>
>>  Hi All,
>>
>> Does anyone know the requirements to copper fill or epoxy fill a
>> microvia?  microvia is via in pad.  Is there an alternative?
>>
>> I have a design that requires a fanout of 3.5 mil trace and 3mil airgap
>> out of a finepitch bga.
>>
>> -oscar
>>
>> ____________________________________________________
>> oscar miguelino | lead pcb engineer | *OQO*, inc.
>> 583 shotwell street | san francisco, ca 94110
>>
>> *(this message constitutes confidential information proprietary to OQO,
>> Inc.)*
>>
>>
>

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