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The Foundry at the Heart of DARPA’s Plan to Let Old Fabs Beat New Ones

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Re: The Foundry at the Heart of DARPA’s Plan to Let Old Fabs Beat New Ones

#22
post #12

Earlier quoted context omitted.

Yes, although this can be an extra challenge in monolithic 3D because it often involves oxide layers and thin silicon * between transistor layers, which makes the heat conduction much worse. *due to violation of Fourier theory of heat.

How difficult would it be to replace current oxide layers with something like BeO?

the same toxic ceramic than in magnetron ? .. scary

Re: The Foundry at the Heart of DARPA’s Plan to Let Old Fabs Beat New Ones

#23

Earlier quoted context omitted.

Monolithic 3D is also sometimes called "sequential 3D". In essence, instead of current 3D integration which fabricates several 2D chips, then thins them, adds TSVs, aligns and then finally bonds them, Monolithic 3D makes 3D chips layer by layer. The advantages are that it can have extremely dense chip to chip connections, as much as ~10,000X as dense as TSVs (literally) and no ESD diode capacitance (can be as much as…

From what I understand, another disadvantage of monolithic 3D are the yield implications. When you fabricate several 2D chips and then integrate them, it allows you to test those 2D chips for errors separately before the integration, which should give you better yields overall.

Yes, that's a major problem as well since it's an exponential issue.
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