- Antenna diodes in the Pentium processor (righto.com)
I was studying the silicon die of the Pentium processor and noticed some puzzling structures where signal lines were connected to the silicon substrate for no apparent reason. Two examples are in the photo below, where the metal wiring (orange) connects to small square regions of doped silicon (gray), isolated from the rest of the circuitry. I did some investigation and learned that these structures are “antenna diodes,” special diodes that protect the circuitry from damage during manufacturing. In this blog post, I discuss the construction of the Pentium and explain how these antenna diodes work.
- Beta Doradus (stars.astro.illinois.edu)
BETA DOR (Beta Doradus). Among the most important of all stars are the Cepheid variables, named after the prototype, Delta Cephei. Many of them dot the naked- eye starry sky, their number including Eta Aquilae, Zeta Geminorum (Mekbuda), even Polaris, the brightest of them (though Polaris’s variations are too small to be witnessed by eye). Here is another bright one, fourth magnitude (averaging 3.76) Beta Doradus, the second brightest star (after Alpha) in the modern southern constellation Dorado, the Swordfish.