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In a list of ICs, along with the familiar package names such as QFN32, LQFP48, etc., I've seen a few ICs to be listed as DIE for the package size. I've never seen that description before as an IC package size, and Wikipedia does not list it either.

What can it be?

I assume it's some kind of chip-scale package, but it does not reveal the silicon size or any other properties, like number of pins, etc.

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2 Answers 2

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Danger Will Robinson!

It refers to a "raw die" -- meaning the chip is not packaged. You will get a piece of exposed silicon (possibly encapsulated or partially so, but typically not).

If you are asking this question, then I'm pretty sure it is not what you want. ;-)

If you want an example...

Consider the Max3967A from Maxim Semiconductor.

If you want to buy the conventional packaged version the part number is MAX3967AETG+, but if you just want the raw microchip inside (no package) you want part number MAX3967AE/D.

In the catalog the "package" for the "/D" version will be "DIE" -- meaning no package.

From page 12 of the datasheet:

enter image description here

You can see they dimension the die in the drawing for you. You will need access to a wire bonding machine in order to use a raw die (among other things).

enter image description here

In this microscope image, you can see two wires bonded (attached) to the package in the center.

And in this photo of a thick-film hybrid circuit (taken with a little less magnification) you can see the wires bonded directly to the various die as well as the package forming the connections between the frame and the outside world:

enter image description here

it is mostly only useful for other IC manufacturers if they want to integrate it into their ICs. So you are right, it's not what I want.

Why you can buy raw dies:

  1. MCM -- What you described in your comment is called a Multi-Chip Module (MCM) and, yes, you are correct.
  2. Low Cost -- It is also common in really cheap electronic devices to skip the cost of packaging. They use unpackaged dies and glue them to the substrate (PCB), bond the pads to the board directly, and then encapsulate the die in an epoxy to secure, seal, and protect everything.
  3. High Reliability -- It can also be done this way for speciality applications where the absence of a package (and the manufacturing and soldering points of failure that come with it) are advantageous for reliability.
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    \$\begingroup\$ So this means if they provide such a purchase for a fairly complex IC, it is mostly only useful for other IC manufacturers if they want to integrate it into their ICs. So you are right, it's not what I want. \$\endgroup\$
    – vsz
    Commented Jan 31, 2013 at 10:46
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    \$\begingroup\$ Your next photo isn't a monolithic IC at all, but rather bare-chip MOSFETs and other components soldered to a substrate, which is in turn mounted in a larger package. The MOSFETs have wire bonds to the substrate, and the substrate has wire bonds to the outer package. \$\endgroup\$
    – Dave Tweed
    Commented Jan 31, 2013 at 13:47
  • \$\begingroup\$ @Dave -- Yeah it's a hybrid circuit. As you point out it shows the wide range of uses of wire bonding. \$\endgroup\$ Commented Jan 31, 2013 at 13:54
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A DIE is the actual silicon chip (IC) that would normally be inside a package/chip. Their just a piece of the wafer disk, but instead of being mounted and connected in a 'chip', and covered with epoxy. You can just buy the wafer piece on it's own. This save a lot of money, but they are much harder to work with. Other than the cost, they also save a lot of space, since you don't have actual pins, etc.

Silicon Die on a fingerIC Die on a circuit board enter image description here

You have probably seen a circuit board for a cheap led screen and it has little black bulge... This is the kind of thing a 'DIE' package is used for. This is referred to as "Chip on Board" as shown below. The left image shows the die directly mounted on the PCB, with the bond wires connected to the copper traces. The right image shows the protective epoxy coating applied after the connections have been made.

Chip on Board
(source: elektroda.net)

You can see a lot more images of dies in a package on my answer to How thick (or thin) is the die/wafer inside an IC.

It would be the "Integrated Circuit Chip" in the picture below:

IC internals

enter image description here

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    \$\begingroup\$ @AlexMoore Thanks, you can see the hires image here And as I mentioned, there are a lot more cools pics in my answer here I love decapsulated chips. I though that was the coolest thing when I was a kid! \$\endgroup\$ Commented Jan 31, 2013 at 16:47
  • \$\begingroup\$ Good answer. This kind of pictures reminds me on how awesome technology is. \$\endgroup\$
    – Rev
    Commented Feb 1, 2013 at 7:55
  • \$\begingroup\$ @bhillam Tanks a ton for the additions! Great pics!! \$\endgroup\$ Commented Feb 1, 2013 at 18:46
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    \$\begingroup\$ @Rev1.0 It's amazing. If you google something like SEM micrograph IC you will see the new-ish tech stuff that is just insanely tiny! Of check out flylogic's blog. \$\endgroup\$ Commented Feb 1, 2013 at 19:02
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    \$\begingroup\$ Anyone notice that the DIP schematic image contains the WRONG unit conversion? 100mil = 2.54mm, not 3.9mm as indicated. \$\endgroup\$ Commented Feb 14, 2013 at 17:34

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