On Mon, 13 Jul 2020 09:37:17 -0700 (PDT), omnilobe@gmail.com wrote:
>I would not handle nitric acid for ten thousand dollars.
Neither would I. The salary of a lab assistant should be far more
than $10,000. More like around $46,000:
<https://www.salary.com/research/salary/benchmark/laboratory-assistant-i-salary/ca>
Ask for a raise, or a hazardous materials handling bonus.
"LABORATORY SAFETY GUIDELINE, NITRIC ACID"
<https://www.ehs.harvard.edu/sites/default/files/lab_safety_guideline_nitric_acid.pdf>
Or, maybe watch a few videos on how to handle nitric acid:
<https://www.youtube.com/results?search_query=nitric+acid>
I had a bottle of nitric acid stored in my closet for many years. It
was properly sealed in double layer polyethylene bottles and the
original shipping container. Apparently, that wasn't good enough.
After about two years in the closet, all the metal items also stored
in the closet corroded into powder. Concentrated ( >60%) nitric acid
will produce a protect oxide layer on the surface of most metals,
dilute nitric acid will not, thus promoting corrosion. That was a
rather expensive mistake as I eventually had to rebuild the closet
down to the framing and sub-floor (because the nails rusted away). I
replaced some drywall because a chemical test showed that there was
some acid absorbed into the gypsum. All the metal buttons and studs
from my jackets and jeans rotted away.
So, I bought a used chemical storage cabinet, installed it outside of
the house, and moved my corrosives and flammables into the cabinet:
<https://www.google.com/search?q=chemical+storage+cabinet&tbm=isch>
Even so, I still had vapor problems in the cabinet, so I built a
separate plastic box just for the nitric acid. That worked.
--
Jeff Liebermann jeffl@cruzio.com
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558
Reply by ●July 13, 20202020-07-13
On Monday, July 13, 2020 at 3:59:48 AM UTC-10, Phil Hobbs wrote:
> On 2020-07-12 11:44, Jeff Liebermann wrote:
> > On Sun, 12 Jul 2020 08:09:07 -0700, jlarkin@highlandsniptechnology.com
> > wrote:
> >
> >> On Thu, 9 Jul 2020 16:14:32 -0700 (PDT), klaus.kragelund@gmail.com
> >> wrote:
> >>> For fun I need to inspect the die in a typical BC847 SOT23 plastic housing
> >>> How do one decap that transistor?
> >>> Cheers
> >>> Klaus
> >
> >> Just curious, why do you want to see the die?
> >
> > To watch them die, of course.
> >
> > BC847BS (matched pair).
> > <https://zeptobars.com/en/read/diodes-BC847BS-matched-pair-bjt-npn>
> > or single:
> > <https://zeptobars.com/en/read/Phillips-BC847C-npn-BJT-transistor>
> >
> > More dead dies (including a few possible fakes):
> > <https://zeptobars.com/en/>
> > 31 pages of decapsulated dead dies.
> >
> > There doesn't seem to be a search feature on the web site, but Google
> > search works. Search for:
> > site:zeptobars.com BC847
> > as in:
> > <https://www.google.com/search?q=site:zeptobars.com+BC847>
> >
> >
> >
>
> For $5 per month on Patreon, you can send chips to the Zeptobars guy for
> decapping.
>
> Cheers
>
> Phil Hobbs
>
> --
> Dr Philip C D Hobbs
> Principal Consultant
> ElectroOptical Innovations LLC / Hobbs ElectroOptics
> Optics, Electro-optics, Photonics, Analog Electronics
> Briarcliff Manor NY 10510
>
> http://electrooptical.net
> http://hobbs-eo.com
I would not handle nitric acid for ten thousand dollars.
Reply by Phil Hobbs●July 13, 20202020-07-13
On 2020-07-12 11:44, Jeff Liebermann wrote:
> On Sun, 12 Jul 2020 08:09:07 -0700, jlarkin@highlandsniptechnology.com
> wrote:
>
>> On Thu, 9 Jul 2020 16:14:32 -0700 (PDT), klaus.kragelund@gmail.com
>> wrote:
>>> For fun I need to inspect the die in a typical BC847 SOT23 plastic housing
>>> How do one decap that transistor?
>>> Cheers
>>> Klaus
>
>> Just curious, why do you want to see the die?
>
> To watch them die, of course.
>
> BC847BS (matched pair).
> <https://zeptobars.com/en/read/diodes-BC847BS-matched-pair-bjt-npn>
> or single:
> <https://zeptobars.com/en/read/Phillips-BC847C-npn-BJT-transistor>
>
> More dead dies (including a few possible fakes):
> <https://zeptobars.com/en/>
> 31 pages of decapsulated dead dies.
>
> There doesn't seem to be a search feature on the web site, but Google
> search works. Search for:
> site:zeptobars.com BC847
> as in:
> <https://www.google.com/search?q=site:zeptobars.com+BC847>
>
>
>
For $5 per month on Patreon, you can send chips to the Zeptobars guy for
decapping.
Cheers
Phil Hobbs
--
Dr Philip C D Hobbs
Principal Consultant
ElectroOptical Innovations LLC / Hobbs ElectroOptics
Optics, Electro-optics, Photonics, Analog Electronics
Briarcliff Manor NY 10510
http://electrooptical.nethttp://hobbs-eo.com
Reply by Piotr Wyderski●July 12, 20202020-07-12
Jasen Betts wrote:
> Hot fuming nitric acid: don't try this at home.
Home is the keyword: HNO3 in concentrations above 3% is unobtainium for
private users per:
https://lovdata.no/static/SF/32013r0098e.pdf
Specifically, its implementation in Poland is punishable by up to 2
years in prison for both the buyer and the seller. I bet the same
curvature of banana geniuses are behind this act as well, as H2SO4 is
still legally available in any concentration and transforming it into
HNO3 requires maybe 50EUR-worth equipment.
So decapping the chip that way can be performed only by a company, sorry.
Try boiling formic acid, if suicide is an option.
Best regards, Piotr
Reply by ●July 12, 20202020-07-12
Thank you all for your answers and ideas
I am on vacation right now but will try when I get back again
The BC847 is just an example. What I am actually doing is to evaluate a competitor product of the BC847. I would like to see if the dies are really close to be the same
Regards
Klaus
Reply by Jeff Liebermann●July 12, 20202020-07-12
On Sun, 12 Jul 2020 08:44:14 -0700, Jeff Liebermann <jeffl@cruzio.com>
wrote:
More:
"How to open microchip and what's inside?"
<https://zeptobars.com/en/read/how-to-open-microchip-asic-what-inside>
Take some microchips of interest and add concentrated
sulfuric acid. Container should be closed, but not airtight,
so that fumes can escape (that is extremely important). Heat
it to boiling temperature (300 �C). White substance at the
bottom is baking soda - it's here to neutralize accidental
spills and part of fumes.
"Part II: How to open microchip and what's inside? Z80, Multiclet,
MSP430, PIC and more"
<https://zeptobars.com/en/read/open-microchip-asic-what-inside-II-msp430-pic-z80>
Put a droplet of fuming nitric or sulfuric acid there, heat
up to ~100 �C (~212 �F). It is critical to use fuming acids
- just concentrated (98% sulfuric or 70% nitric) won't cut
it. After reaction ends - rinse with acetone, dry and put
next droplet.
As a result we are getting exposed die, with all bond wires
intact. The microchip still works - this might be useful
if we want to probe it or modify eeprom data with UV laser.
Please remember that you have only one life to give for your
profession or hobby. Otherwise, this looks like fun.
--
Jeff Liebermann jeffl@cruzio.com
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558
Reply by Jeff Liebermann●July 12, 20202020-07-12
On Sun, 12 Jul 2020 08:09:07 -0700, jlarkin@highlandsniptechnology.com
wrote:
>On Thu, 9 Jul 2020 16:14:32 -0700 (PDT), klaus.kragelund@gmail.com
>wrote:
>>For fun I need to inspect the die in a typical BC847 SOT23 plastic housing
>>How do one decap that transistor?
>>Cheers
>>Klaus
On Thu, 9 Jul 2020 16:14:32 -0700 (PDT), klaus.kragelund@gmail.com
wrote:
>Hi
>
>For fun I need to inspect the die in a typical BC847 SOT23 plastic housing
>
>How do one decap that transistor?
>
>Cheers
>
>Klaus
Just curious, why do you want to see the die?
--
John Larkin Highland Technology, Inc
Science teaches us to doubt.
Claude Bernard
Reply by Hul Tytus●July 12, 20202020-07-12
Klaus - I tried methylene chloride with no luck. I'm guessing that heat cured
epoxyies are hardier that room temperature cured types. Next step would be
a pressure capable container and a heater and a pressure relief valve.
Hul
klaus.kragelund@gmail.com wrote:
> Hi
> For fun I need to inspect the die in a typical BC847 SOT23 plastic housing
> How do one decap that transistor?
> Cheers
> Klaus
Reply by bitrex●July 10, 20202020-07-10
On 7/10/2020 4:22 PM, bitrex wrote:
> On 7/10/2020 1:11 PM, Phil Hobbs wrote:
>> On 2020-07-10 00:04, jlarkin@highlandsniptechnology.com wrote:
>>> On Thu, 9 Jul 2020 20:05:47 -0700 (PDT), Phil Allison
>>> <pallison49@gmail.com> wrote:
>>>
>>>> John Larkin wrote:
>>>>
>>>> ==================
>>>>>
>>>>> Squeeze it sideways in a vice. Sometimes the package will shear apart
>>>>> and expose the chip.
>>>>>
>>>>
>>>> ** Most likely take to top layer of the chip with it.
>>>>
>>>> Happens all the time with TO220 and TO3P paks.
>>>>
>>>> Only metal can paks ( TO18, TO5, TO3 etc) are amenable to chip
>>>> observation.
>>>>
>>>>
>>>> .... Phil
>>>
>>> I squeezed these in a big bench vice
>>>
>>> https://www.dropbox.com/s/4nxm7m2q3j3buvc/ExFets.jpg?raw=1
>>>
>>> just to see what they looked like, after we blew them up exploring
>>> analog safe-operating areas.
>>>
>>> We found a couple of big switchmode fets that were good as linear
>>> amps.
>>
>> You can also decap a DIP by connecting the mains across the two rows
>> of pins. Makes a nice crater--point it away from your face when you
>> do it.
>>
>> Unfortunately it also ablates the chip. Nice bang though.
>>
>> Cheers
>>
>> Phil Hobbs
>>
>>
>
> Certain MSI motherboards have that decapping-mode as a built-in feature
> for DPAK FETs in the CPU synchronous buck where they half-assed the
> high-side gate driver and just used a power FET totem pole for the
> high-side gate driver instead of a integrated thinger.
>
> They under-specced it and it can get into a thermal runaway situation
> when e.g. the CPU fan or liquid coolant loop fails, but before the CPU
> thermal limiting kicks in. Pop!
Not a gentle pop. More like if the PC box is in the same floor of the
house with you that'll definitely wake you up.