🚀 go-pugleaf

Bobby Mozumder <snm6394@vmsmail.isc.rit.edu> wrote:
>For my microelectronics engineering senior project at RIT, I'm trying 
>to create a bonded and etchbacked SOI device using a process similiar 
>to S. Nakamura et al. as described in IEDM Technical Digest, '95 (p. 
>889).  They created SOI DRAM devices by going through a normal CMOS
>process and then flipping it over to bond on a substrate and etching 
>away the back side until they were able to isolate the devices, thus
>creating SOI devices after fabrication of the devices, as opposed to
>buying SOI wafers and then creating the devices on top of that.

(snip)

>I need some help specifically on the bonding process.  Can anyone 
>give me good references on the actual bonding process, preferably
>something that is available over the net?  Will BPSG bond with it 
>at that temperature?  What about air pockets?  How do people get 
>rid of that?  Is this method safe and cheap?  Will the bonding 
>affect the device?  (I will start SUPREME4 simulations next week, 
>but in the above paper, they were able to create 64MB dram devices.)


I don't know beans about solid state fabrication.  However, if you take 
two (reasonably) flat surfaces, give them a quick ion wash in vacuo 
(clean surface), touch them together, press and and warm (and maybe set a 
voltage across for a little mobile ion migration)... you end up with a 
monolith.  I know physics grad student who touched two silica optical 
flats together in a vacuum chamber.  It may only have been van der Waals, 
but it was enough.


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