How vulnerable to static destruction are transistors compared to ICs?

[Thecomedian]

I've bought some bulk transistor sales in the past, and one of them actually came with all of them stuffed in a cardboard box touching styrofoam with nothing inbetween.

If all the transistors are meshed together touching legs all together, are they more protected from static build up and destruction than a single transistor rubbing over a surface which can build static? The legs being isolated would mean charge can be built up on it, while if they're all wadded together, There's endless connections that prevent charges from building up, right?

Can they be stored in lump in a regular plastic bag? Is a static shield bag overkill for transistors?

[R.G.]

Junction semiconductors (diodes, bipolars, UJT, etc, and most JFETs) are so UNaffected by static that it was not known that it was bad for them until the sudden deaths of MOSFETs touched off research into static effects on semiconductors.

MOSFETs die suddenly and finally when their gate insulation is punched through. Static punchthrough isn't really good for any device, but the damage is quite small for energies that don't heat junctions enough to damage the junctions locally. Many junction devices are rated for avalanche duty, meaning they will withstand being broken over by voltage/energy bursts on a fairly constant basis.

So don't sweat the junction devices. Worry about the MOS devices.

[gritz]

^^What he said!^^

I've noticed that some distributors tend to send everything (including static insensitive semiconductors, resistors, caps and whatnot) in antistatic packaging these days - I guess because it saves packaging inventory and training for the folks in despatch. This is not an entirely good thing - back in the mists of time if something arrived marked "static sensitive" then at least we knew it was and treated it as such!

I used to work in a cleanroom, so wearing an antistatic wriststrap when necessary isn't an inconvenience. They work just as well around an ankle (so long as there's contact with the skin) and then they don't get in the way when doing fiddly stuff. Some people have doubtless spent their entire pedalbuilding lives handling static sensitive devices without taking precautions and have never damged anything (and will tell you so), but you just don't know...

As the chief says bipolar transistors and junction field effect transistors are safe, as well as diodes and bipolar / junction field effect opamps (like our favourite TL072). Anything marked "MOS" or "CMOS" isn't though. If in doubt grab the datasheet when you order something (this is always a good idea anyway).

[armdnrdy]

I just received an IC (ISD1620BSY) today in a moisture barrier package. Inside the package was a desiccant (bag of silica gel) as well as a HIC card (Humidity Indicating Card)

On the package there is a sticker that states: CAUTION This bag contains MOISTURE SESITIVE DEVISES.

On the sticker there are items the packer had to fill in and date a "bag seal date".

I checked the data sheet and could find no mention of this IC being "moisture sensitive"

Any clues to this mystery? 

[kingswayguitar]

I just received an IC (ISD1620BSY) today in a moisture barrier package. Inside the package was a desiccant (bag of silica gel) as well as a HIC card (Humidity Indicating Card)

On the package there is a sticker that states: CAUTION This bag contains MOISTURE SESITIVE DEVISES.

On the sticker there are items the packer had to fill in and date a "bag seal date".

I checked the data sheet and could find no mention of this IC being "moisture sensitive"

Any clues to this mystery? 

not sure,
but do tell...
is that IC a fun score?

[armdnrdy]

is that IC a fun score?

Not sure what you mean by fun score. Free? No, I purchased it from Digikey.

Or, if you meant did I score this to build something for fun, other than stompbox. No to that as well.