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Why all ICs have black color?

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why IC are black?

Cause semiconductor devices are light sensitive
 

why IC are black?

light sensitivity of semiconductors
 

Re: why IC are black?

the housing is backalite which is black in colour. it provides good protection against light and humidity and very easy to use in fabrication process.
 

Re: why IC are black?

FvM said:
Cause semiconductor devices are light sensitive
Click to expand...

Which light?
IC chip packaged and closed from outside, and no light could transpierce.
Can you explain further.
 

why IC are black?

ok....good ans but why not other colors?
like dark blue.....
can any one further explain me???
 

Re: why IC are black?

IC chip packaged and closed from outside, and no light could transpierce
Click to expand...
What do you mean? Do you expect the circuit to be mounted in an opaque enclosure? I think, the discussion is about usual molded IC packages, they have no other light barrier than the black filled package epoxy and they may be directly light exposed in some applications.

Interestingly, today's small (and thin) SMT packages don't provide sufficient light protection for sensitive analog IC, you can find respective hints in some manufacturers datasheets.

Regarding colour of package material: Only black filled material is absorbing all possibly interfering UV to NIR spectral components.
 

Re: why IC are black?

FvM said:
IC chip packaged and closed from outside, and no light could transpierce
Click to expand...
What do you mean? Do you expect the circuit to be mounted in an opaque enclosure? I think, the discussion is about usual molded IC packages, they have no other light barrier than the black filled package epoxy and they may be directly light exposed in some applications.

Interestingly, today's small (and thin) SMT packages don't provide sufficient light protection for sensitive analog IC, you can find respective hints in some manufacturers datasheets.

Regarding colour of package material: Only black filled material is absorbing all possibly interfering UV to NIR spectral components.
Click to expand...

Dear FVM
If so, could you explain why some types of optocoupler are white (light yellow or cream) ?
 

Re: why IC are black?

If you are motivated to start a research project on this topic, I suggest to dissect this devices and perform precise measurements of transparency respectively opacity of the diverse materials.

My point was rather qualitative, I wanted to remind the fact, that semiconductor devices are light sensitive to some extent, and that there are known issues with thin packages, believe it or not.

Regarding the said white molding material, a high filling with a suitable white opaque powder is also light absorbing, but less perfect than black powder, particularly carbon (soot) that's mostly used for critical optical moldings.

P.S.: Just a supplement from Toshiba TLP281 (white molding) data sheet:
(Note 2) Because of the construction,leak current might be increased by ambient light. Please use photocoupler with less ambient light.
Click to expand...
 

Re: why IC are black?

Waaoo,
The reasons
- Matter to make the plastic used is black
- Plastic packaging is low cost and easily manufacturable compared to ciramic
- Some circuits like erasable memories requires to be in opack packages.
- Black helps evacuating heat outside the chip.

Check the link in my previous post.

jigisha said:
ok....good ans but why not other colors?
like dark blue.....
can any one further explain me???
Click to expand...

When we make bread it is brown. You can make red, yellow or green bread but you have to pay more for color added a thing which would not be appreciated by a large number of bread consumers coz at the end, bread is bread and the tast is the same, the role is the same : figth the hunger.
Personly If I have the choise between bread with a piece of cheese and a Green bread (that have an equivalent price) I'll choose th Cheese with bread. What about you ?
 

Re: why IC are black?

Coz Beetles are Black
Click to expand...
I really appreciate this plausible explanation.

Actually I wasn't aware of how grimly the topic had been already discussed. Thanks to AdvaRes for linking a short review. I think, the topic would be better placed at the Elementary Electronic Questions forum.
 

Re: why IC are black?

Hi Davood,

Optocouplers are special cases. They are hybrid electro-optical devices. White resin also means better reflection between LED and Receiver (when they replaced on the same planar). So coupling is better, and the distance (known as DTI) can be increased easily to satisfy extreme conditions. Moreover, the working voltage will e higher

You can compare two same packages (DIP8) with black and white in Avago Optocouplers: ACPL-3130 and ACPL-J313

Former has 0.08mm DTI, latter 0.5mm.

Best regards
Hakeen
 

Re: why IC are black?

ic made of silicon..
 

Re: why IC are black?

1. economy
plastic is cheap and the colour availability black is cheap

2. technology
quick setting, strength finishing etc
 

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