Decapping ICs (removing epoxy packaging from chips to expose the dies)--- make money online

I thought it would be interesting to try decapping some chips. This involves using fuming nitric acid, which also seemed fun, so I thought I would give it a go. The process starts by milling a precise pocket into the IC using my CNC machine. I used carbide tooling to cut the glass fiber/epoxy material. I then put a drop or two of the acid into the pocket, and raised the temperature to about 100*C. The acid dissolves the epoxy packaging as it sort of "dries". I added more acid to the pocket every few minutes. After about 10 minutes, I washed the IC in acetone, then reapplied acid if there was still material left on the die. Eventually, it was all cleared away, and I had a nice decapped IC.

hey everyone I got interested in

decapping integrated circuits which

means dissolving away the epoxy package

and exposing the die so that you can

either see what the die looks like and

figure out perhaps what the circuit is

or just probe the die while it's the

chip is you have power so let me show

you how I did this initially I started

just using a dremel to remove a lot of

the epoxy packaged material but I found

that that was very inaccurate as it

turns out the acid etching process which

I'll describe later is very dependent on

having a uniform pocket for the acid to

sit in so for my first real attempt

after playing around a little bit the

Dremel I decided to use the CNC mill so

I drew up a little pocket in the CAD

tool and then mounted the I see in the

CNC vise and got it carefully set up and

then milled the pocket out so I had a

really nice even consistent depth pocket

and for these chips I've been decapping

just 74 series logic and 4000 series

logic all 14 and 16 pin dip packages and

the thickness that I've been removing is

about 40 to 50 thousandths from the top

of the package so I could probably have

gone a little bit deeper the trick is if

you go too deep the bond wires get cut

and then you can't run the chip which

may or may not matter I mean depending

what you want to do with the decap chip

so after I had the pocket milled I blew

the dust out and then initially I tried

to etch the package away at room

temperature so I put a drop or two of

fuming nitric acid into the milled

pocket and waited for a while but at

room temperature it's either going to

take way too long or it's not going to

work at all so I started up the hot

plate and then put the ICS in a little

ceramic container and put that on the

hot plate and then put the drops of

nitric acid into the milled pockets

while it was all on the hot plate there

and I got it up to me and maybe around

100 degrees see some of the vague

instructions that I found on the web

indicate maybe 140 degrees C even but

the temperature seriously speeds up the

reaction it speeds it up so much that

you

can put just a very small amount of

nitric acid in the pocket you don't even

really have to fill it up all the way

and the heat will cause it to bubble and

froth and eventually it sort of dries

out I'm not really sure what's happening

there but the liquid either soaks into

the pass you package or it dissipates

and so you can put a drop on then wait

five minutes and put another drop on and

it sort of keeps it very moist but not

overflowing with acid if the acid

touches the dip leads it fumes

vigorously and is obviously dissolving

away the metal which what you don't

really want so periodically I would take

the chips out of the the hot plate

container and rinse them in some acetone

and then I've used the acetone wash

bottle to kind of blow out as much

dissolved epoxy that I could after a few

iterations I could see that the dye most

of the bond wires were exposed so I took

it out and soaked it in some clean

acetone and rinsed it again and then put

it under the microscope and had a look

and sure enough

yeah the bond wires are all intact

everything looks okay the dye is visible

and you can clearly see what's on the

dye I haven't really done a whole lot of

careful consideration about what

actually going to do with these D caps

chips I was mostly interested in just

playing with nitric acid and this is one

of the cool things you can do with it

obviously gun cotton and flash paper

will be coming up I'm not really sure if

you need fuming nitric acid to do this

or not

I heard that you do and going through

all the hassle of getting nitric acid is

difficult enough and so getting fuming

versus just concentrated it was not that

big of a deal I mean the difference in

difficulty so concentrated is like 68

percent and fuming is as close to 100%

as you can get it basically there's also

a white fuming and red fuming nitric

acid the red fuming has a lot of

nitrogen oxides dissolved in it and the

white fuming is relatively free of of

nitric of nitrous or nitrogen oxides

okay well I hope you enjoy that let me

know what you think I should do with

these decap disese I've been thinking

I'd like to you know probe them while

the thing is running I don't really have

probes small enough to do this but you

know I maybe i'll decap a larger chip

that's cheap enough to do just kind of

play around with I think I've got the

technique down almost well enough where

I wouldn't have to worry about

destroying the chip but I'm still kind

of getting the hang of this so you

wouldn't want to start with an expensive

chip okay

see you next time byeTop Paid Keyword :  earn cash online, google make money from home, earn money online without investment by clicking ads, free earn money website, online money making jobs, earn money online without investment by typing, online work for money, best online earning sites, make money online with google, online earning websites, money making websites, online earning websites for students, invest online and earn money, best online money making, online money income, view ads and earn money without investment, earn money online by clicking, online money income site, money earning sites, online earning sites, best website to earn money, free money earning sites, money earning websites, get money online, online earning tips, online earning without investment, earn money online without investment for students, earn money by clicking ads, earn money online without investment, online earn money website, online jobs to earn money, best online income site, top 10 online money earning sites, easy income online, easy online earning, earn money online from home, make money online legit, earn money online free fast and easy