Addendum
To "Flip n' Print?"
Other options:
Flip n' Autocatalytic method
Pick and place all SMD's and pot assembly.
Inkjet liquid palladium for your desired circuit traces.
Autocatalyticly "grow" gold or copper traces to the desired thickness.
For emulation of multi-layered construction, Inkjet NON-Conductive ink to cross-over areas (as an insulating mask).
Flip n' Stitch method
Pick and place all SMD's and pot assembly, then send out to be "stitched" (ultrasonic wire bonded) with special "INSULATED" X-wire bonding wire) Note: This method requires the use of the "wire bondable type" discrete SMD's. This method also allows the direct connection to a bare IC die.
This method creates point to point and multi-point "air wire" or "rats nest" connections in gold, copper or aluminum insulated wires. The air wires can be potted for protection.
Note: A good "used" wire bonder goes for about $ 8 to $ 10K "
so send it out for stitching! : )
Note: All methods are "solder-less" and without the need to fabricate a conventional multi-layered fiberglass "PCB".
All proposed methods here are only concepts offered for investigation and/or development.
--- In Homebrew_PCBs@yahoogroups.com, "Richard" <richard.liberatoscioli@...> wrote:
>
>
> Hello Homebrew Printed Circuit Group!
>
> I have successfully modded my Epson Artisan 50 printer Epson Printer
> Mod
> <http://groups.yahoo.com/group/Inkjet_PCB_Construction/photos/album/1664\
> 97487/pic/list> to make PCB boards. I did this, as I'm sure as all in
> this forum, want to quickly build working devices from all the many
> awesome microchips out there (ie: MCU, RFID,WIFI,GSP, etc.)
>
> In my current project, I need to fabricate a "system-in-package" (SIP)
> module containing an RFID reader chip (QFN), MCU chip and WIFI
> chip(QFN) on two PCB's (1 1/4" x 3/4") including the required discrete
> SMD's (resistors, capacitors, inductors, x-tal, etc).
>
> This project requires very small SMD's and a very small and dense
> multi-layer PCB with micro vias for fabrication.
>
> This project well exceeds my existing "Homebrew" equipment capability to
> fabricate this module.
>
> In assessing the demands for the size and scope of this project (for a
> "homebrew" solution) the "show stopper" was all in the fabrication of
> the PCB itself.
>
> Here I began my quest for a different "homebrew" solution.
>
> Could I build this module without the complex multi-layer PCB?
>
> Could I interconnect all SMD's (IC's and discrete's) without soldering?
>
>
>
> Concept proposal:
>
> Start with a blank substrate (metal, glass, FR4,ceramic,etc) in place of
> a conventional PCB.
>
> Apply double sided releasable 3M "micro adhesive" tape covering the top
> surface of the substrate.
>
> "Pick and Place" all SMD's onto the top surface of the substrate. Note:
> with no PCB traces or vias to contend with, a 50% reduction in SMD
> spacing is obtained.
>
> "Epoxy Pot" the top surface embedding all the SMD's.
>
> Flip over the substrate (now working from the bottom side) and release
> the tape and substrate from the potted assembly. Clean off any residual
> adhesive.
>
> At this point, you should see only the exposed metal contacts of all the
> SMD's.
>
> Using the modified Epson Artisan 50 printer (set head height to pass the
> 1/8" thick epoxy pot assembly depth) and print with special UV curable
> conductive ink (Metalon®)
>
> UV cure (need to build a "homebrew" UV source for curing the conductive
> ink). The commercial version does it in 3 or 4 seconds.
>
> Subsequent conductive traces (emulating the multi-layers of a
> conventional PCB) are first "masked out" by printing with a different
> inkjet of NON-conducting ink at the conductive trace crossovers.
>
> DONE! : )
>
>
>
> [Non-text portions of this message have been removed]
>