I'm really glad that last slide is in the article because I've been wondering this about Intel's push to become the king of thru-silicon vias, but didn't want to be the one sounding ignorant. When you etch holes in glass, fill the holes with metal, then solder it to something else, how does it not just shatter? The article just acknowledges the issues without suggesting where the solutions might come from.
True, but those metal/glass devices are made by joining a pair of a certain metal alloy with a certain kind of glass, which are chosen to have matched thermal expansion, for instance kovar alloy with borosilicate glass.
If you join a random metal-glass combination, it will fail soon. When incompatible metals and glasses must be joined, the metal is covered with an alloy and the glass with another kind of glass, so that at the interface you have a matched pair. Sometimes more layers with different kinds of glasses are used, to ensure a gradual change in the coefficient of thermal expansion, so that no adjacent glasses would differ too much, which would cause cracking when the temperature varies.
In TFA it is discussed that the problem is that copper has a much higher thermal expansion than any glass, so you cannot match it. Moreover, at the very small sizes that are desired, it is hard to cover copper with some other metal that is matched with glass, without leaving too little volume for the copper, which would increase the electrical resistance.
For the manufacturing of electronic vacuum tubes and also for the first transistors and integrated circuits, which were packaged in metal cans, the discovery of the kovar alloy, which can match the thermal expansion of a certain glass, was a necessary precondition. Kovar was a derivative of the invar alloy, which has a much lower thermal expansion than most metals.
My intuition is that you get shattering when one part of the glass wants to warp across or away from another part that can't. Because of how thin the glass is in these processes, you mostly get warping and edge chipping, rather than something that can propogate catastropically
I'm really glad that last slide is in the article because I've been wondering this about Intel's push to become the king of thru-silicon vias, but didn't want to be the one sounding ignorant. When you etch holes in glass, fill the holes with metal, then solder it to something else, how does it not just shatter? The article just acknowledges the issues without suggesting where the solutions might come from.
Depends on the co-efficient of expansion of the metals and the physical strength of the glass.
Metal/glass insulators have been a thing for 100+ years, for example [https://www.victorinsulators.com/products/transmission-produ...].
True, but those metal/glass devices are made by joining a pair of a certain metal alloy with a certain kind of glass, which are chosen to have matched thermal expansion, for instance kovar alloy with borosilicate glass.
If you join a random metal-glass combination, it will fail soon. When incompatible metals and glasses must be joined, the metal is covered with an alloy and the glass with another kind of glass, so that at the interface you have a matched pair. Sometimes more layers with different kinds of glasses are used, to ensure a gradual change in the coefficient of thermal expansion, so that no adjacent glasses would differ too much, which would cause cracking when the temperature varies.
In TFA it is discussed that the problem is that copper has a much higher thermal expansion than any glass, so you cannot match it. Moreover, at the very small sizes that are desired, it is hard to cover copper with some other metal that is matched with glass, without leaving too little volume for the copper, which would increase the electrical resistance.
For the manufacturing of electronic vacuum tubes and also for the first transistors and integrated circuits, which were packaged in metal cans, the discovery of the kovar alloy, which can match the thermal expansion of a certain glass, was a necessary precondition. Kovar was a derivative of the invar alloy, which has a much lower thermal expansion than most metals.
My intuition is that you get shattering when one part of the glass wants to warp across or away from another part that can't. Because of how thin the glass is in these processes, you mostly get warping and edge chipping, rather than something that can propogate catastropically
https://en.wikipedia.org/wiki/Borosilicate_glass Uses / Electronics It's at least much more resistant to temperature shocks than regular glass.
I had to read this for quite a while to be sure they weren’t actually talking about boxes
It's just very small boxes.
This article is kinda worthless for layman without pics and examples.
In which kind of bespoke packaging do they use glad?