 Hi, I'm Rob, and this is my chemical fume chamber of horrors. So today what we're going to do is decapsulate a plastic chip using hot sulfuric acid. And I have a beaker, a little beaker, and a chip, a little chip. It's a plastic chip, so it will effectively melt in hot sulfuric acid. So, what I'm going to do is take the sulfuric acid, this is concentrated or azeotropic sulfuric acid, also known as 98% concentrated. And I'm going to put something like 20 milliliters in it using this plastic pipette. This is a 3 millimeter pipette. So, we're just going to dump some in about 2 or 3 milliliters at a time, up to about 20 milliliter level. This is just enough to cover the chip. So, here we go with the first 2 or 3 milliliters, and this can get boring pretty quickly. So, we're just going to speed up time and drop some acid into the beaker, that is. So, once we've finished with 20 milliliters, we're going to just set it on the hot plate. And I'm going to set the pipette aside because it is a little bit wet with sulfuric acid. Cap off the sulfuric acid and set it safely aside. Now, I have this temperature probe that I made after the one featured in NerdRage. It's basically just a glass pipette with a thermometer in it, with a thermocouple in it. And I've hooked it up to my Fluke multimeter, and now I'm measuring the temperature in Celsius. So, it's 21 Celsius. And I'm going to put it in the beaker because what I want to do is turn on the hot plate. I'll just turn it all the way up, and I want to go all the way up to 200 Celsius on the Fluke. 200 Celsius is hot enough to essentially melt or actually oxidize or dehydrate the plastic resin that forms the plastic body of the chip. So, since this can get pretty boring, we're just going to fast forward. Yeah, zoom, zoom, zoom, zoom, zoom. And, okay, so what I want you to see is that round about 115, we start seeing some brown stuff coming off the chip. This will rapidly turn black. This is basically the carbon being dehydrated off of the resin, and it's essentially breaking down the resin. So, the solution will continue to turn blacker and blacker, and I can pick it up and swirl it around a little bit, and the solution is basically black at this point. This is all carbon. So, this is good. It means the chip is being dissolved. So, let's keep going to 200 Celsius. Getting the rest of the way to 200 takes another minute or so, and we're done. Now, this isn't my usual practice, but I decided to take the beaker off of the hot plate and just let it cool down to see what I ended up with. Usually what I do is I leave it for about 10 minutes at 200, and that, I believe, actually does the job of melting the chip, but I wanted to see what would happen if I just let it go. So, let's fast forward while we cool this down, and this part takes about 10 minutes or so, a little less. So, hooray for time-scaling. Okay, so we're done. It's about 65 Celsius or so. That's good enough. So, I'm setting the thermometer off to the side somewhere relatively safe where it's not going to touch anything, because it's got acid on it, basically. Now, I have a little beaker over here that I'm just going to pour out the slightly hot mixture into. Because of the shape of the beaker, the chip or whatever remains of the chip should not come out of the beaker as long as you do this gently. So, just gently pouring it out and getting a couple of drops, final drops out, taking a look, and we're going to see, maybe, what's inside. Can't wait to get those final drops out. So, great. So, I'm going to set that aside. That's used acid that I can use later, maybe for distilling. And I'm looking inside the beaker, and right now, I get a sort of sinking sense of disappointment, because I actually see the chip in there, and not much has happened to it. Unfortunately, you can't see it because the chip is black and the residue is black. So, basically what I'm going to do is I'm just going to put the acid, which is perfectly fine. It's just got some carbon in it. I'm going to put it right back into the beaker, and I'm going to heat it back up to 200, and then I'm going to leave it for 10 minutes, as I usually do when I do this sort of thing. So, let's go ahead and do that. Up to 200C in about 14 minutes or so, and to cool down to about 75 or so, takes another 7 or 8 minutes. Alright, so let's see what we have. And take the dirty thermometer out, get all those drops off, put it in that beaker temporarily, and set this aside, and now it's a little bit cramped in my fume chamber, so I'm a little bit careful about how I maneuver and where I put things, so bear with me while I shift things around. Alright, so here's my beaker, and here is my flask. So, again, pouring it out slowly, and this time I'm pretty sure that I have the dissolved chip in the flask. Alright, there we go. So again, I set the used acid aside. I can maybe distill it later to recover some more concentrated sulfuric acid and get rid of that black stuff. Now, in the flask, I'm looking and I don't actually see an intact chip, which is good. It means that the only thing that's there are pins. So, I take the distilled water, well, pins and the dye of course, and the lead frame, which is just metal. So I'm just going to take some distilled water and pour it in. Now, they say that you should never add water to acid, but of course I'm adding water to excess. So there really isn't any risk of a runaway reaction here. I'm basically filling it halfway or so and swirling it around, maybe cleaning the sides. The water acid mixture is still pretty dirty because there's a lot of carbon. Now, I've got this other beaker with watery acid in it. So I can distill that off as well later on, but I'm basically pouring off the dirty water very carefully. And now we can actually see that we've got a bunch of dregs, which consists of the pins, the lead frame, and the dye. So that's pretty good. Let's give it another wash because the next step is actually going to be taking this and just washing off the dye with some acetone. And there it is. Let's take a look at it a little closer. But first, let's tidy up. I'm going to put my beaker of watery acid aside, and this is the flask that I'm keeping the used acid in until I can distill it. And I'm just going to pour off whatever I got and store it until I can distill it off. Great. Everything's clean. I can now move on to the next step. So here I am in my kitchen, which I do not use for food preparation because I eat from the microwave. Anyway, so there is my stuff in the flask. So what I'm going to do is I'm going to take a beaker about the same size, and I'm going to take some distilled water again and give it a little bit of a wash. And this actually isn't so much a wash as just a means of dumping everything into the beaker. So I'm going to swirl it around, get it ready to dump out, and here we go. Except there is still stuff in my other beaker, so here we go. Dumping it out in three, two, one. There we go. So that basically carries all of the stuff out of the beaker. And now I've got a much more convenient beaker, and I can reach inside and grab things from it. So let's see what I can see. What am I doing here? I am pouring off the water first so that all I have left is a little bit of wet stuff in there. And I'm going to take some tweezers. These aren't metal tweezers. These are just plastic tweezers. And I'm going to locate the die and pull it out. It's actually attached to a little bit of lead frame, but it's there. I didn't know it at the time, but yes, it is actually there. So I'm just sort of picking through the rest of the debris, wondering where the die is, but then I soon realized that the die is actually attached to that central portion of the lead frame. Yes, zooming in. No, not on the Q-tip. Yes, on the die. Now there are very thin wires attaching a couple of pins to it, so I'm just going to pull those. No big deal. The wires will break very easily, and I will attempt to get the camera to focus on the die. And it's very small, but it's there. And that's really it. That's how you decap a chip with hot sulfuric acid.