it might have application on true north type of chip (IBM), low power
(super low power) cross bar type with "large pitch" it could be
running much cooler than any other chips... the existing chip almost
hit the Moore limit... 10 nm - apple got a lot of problem (vendor)..
7 nm is not something I am looking for (I am out of the field now...
not my worry). but I do agree with all the others, BiSn is not easy
stuff for mechanical testing... unless someone figure out to add some
polymer without impact electrical performance. (ternary or quaternary
stuff are bit scary... stability issue under pressure).
On Feb 14, 2017, at 7:28 PM, Wayne Thayer wrote:
> Another concern with an alloy with a designed reflow oven
> temperature of 180C is that the melting point is going to be around
> 145C. As devices run hotter and hotter, being so close to the
> melting point may decrease fatigue life significantly. Maybe Lenovo
> has defined the parameters for the attachment process and told the
> designers what the new boundary conditions are--for example, if
> fatigue life goes down due to the new alloy, bring it back up to
> acceptable by decreasing max operating temperature, reducing max
> component size, etc. Or maybe they figured out their products are
> lasting too long anyway!
>
> Wayne
>
> -----Original Message-----
> From: TechNet [mailto:[log in to unmask]] On Behalf Of David Hillman
> Sent: Tuesday, February 14, 2017 4:02 PM
> To: [log in to unmask]
> Subject: Re: [TN] New Solder Alloy
>
> Hi TechNet - I will echo Andy's comments, the SnBi solder alloy
> system may have some application in some products but a number of
> solder alloys in the SnBi alloy family have been extensively
> investigated and found to not be applicable for a large segment of
> high performance product types/use environments.
>
> Dave
>
> On Tue, Feb 14, 2017 at 2:06 PM, Giamis, Andy
> <[log in to unmask]>
> wrote:
>
>> Interesting.
>> I tore apart a certain smart phone a few years back and saw that they
>> attach heat shields/heat spreaders to the PCB edge with Sn-Bi.
>> The PCBA
>> was amazing but I thought the Sn-Bi solder joints had wetting issues
>> and many of the solder joints were cracked. Sn-Bi seems to be
>> rather brittle.
>> It would be interesting to see how this particular alloy performs.
>>
>>
>>
>> -----Original Message-----
>> From: TechNet [mailto:[log in to unmask]] On Behalf Of Mike Buetow
>> Sent: Tuesday, February 14, 2017 11:38 AM
>> To: [log in to unmask]
>> Subject: Re: [TN] New Solder Alloy
>>
>> I have been in touch with Lenovo about the alloy, which is a
>> tin-bismuth alloy developed in concert with Alpha and Senju. There's
>> some info in the link below based on what I've learned.
>> http://circuitsassembly.com/ca/editorial/menu-news/27004-
>> new-lenovo-lts-lowers-melting-temp-cuts-co2-emissions.html
>> Best,
>> Mike
>> -------- Original message --------From: "Vargas, Stephen M" <
>> [log in to unmask]> Date: 2/14/17 9:19 AM (GMT-08:00) To:
>> [log in to unmask] Subject: [TN] New Solder Alloy Got news of this
>> from a
>> colleague. Interesting... would love to hear comments from the
>> TechNet
>> group.
>>
>> http://news.lenovo.com/news-releases/lenovo-announces-
>> breakthrough-innovative-pc-manufacturing-process.htm
>>
>> Regards,
>> Steve Vargas
>>
|
