Question

What devices work better using indirect bandgap semiconductors?

Answer 1

What devices work better using indirect bandgap semiconductors?

Possibly this question would be better on Electrical Engineering SE because it concerns the uses and technological exploitation of indirect bandgap materials rather than the physics behind such devices. – ...

The usual issue is with emission, not absorption. ...

Indirect gap materials are used in photodiode detectors.

Answer 2

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In an indirect bandgap semiconductor, a photon must couple to a phonon to be absorbed. This makes the absorption coefficient much lower (and hence solar devices must be thicker), and produces heat in the lattice. Many other disadvantages of using indirect bandgap semiconductors over direct bandgap semiconductors. However, no devices are described in which the indirect gap is used to technological advantage.