Semiconductors can become conductive if their temperature is raised sufficiently to populate the (empty) conduction band from the highest filled levels in the valence band. The ratio of the populations in the highest level of the conduction band to that of the lowest level in the conduction band is

where ΔE is the band gap, which is 1.12 eV for Si and 5.5 eV for diamond. Assume for simplicity that the ratio of the degeneracies is one and that the semiconductor becomes sufficiently conductive when

At what temperatures will silicon and diamond become sufficiently conductive? Given diamond sublimates near 3000 K, could you heat diamond enough to make it conductive and not sublimate it?

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Econduction -AE /k„T nconduction Evalence Nyalence Nconduction - 5.5 ×10 nyalence %3!